Wind disturbance as a green method can effectively prevent the overgrowth of tomato seedlings,and its mechanism may be related to root system mechanics.This study characterized the biophysical mechanical properties of...Wind disturbance as a green method can effectively prevent the overgrowth of tomato seedlings,and its mechanism may be related to root system mechanics.This study characterized the biophysical mechanical properties of taproot and lateral roots of tomato seedlings at five seedling ages and seedling substrates with three different moisture content.The corresponding root system-substrate finite element(FE)model was then developed and validated.The study showed that seedling age significantly affected the biomechanical properties of the taproot and lateral roots of the seedlings and that moisture content significantly affected the biomechanical properties of the seedling substrate(p<0.05).The established FE model was sensitive to wind speed,substrate moisture content,strong seedling index,and seedling age and was robust.The multiple linear regression equations obtained could predict the maximum stress and strain of the root system of tomato seedlings in the wind field.The strong seedling index had the greatest impact on the biomechanical response of the seedling root system during wind disturbance,followed by wind speed.In contrast,seedling age had no significant effect on the biomechanical response of the root system during wind disturbance.In the simulation,no mechanical damage was observed on the tissue of the seedling root system,but there were some strain behaviors.Based on the plant stress resistance,wind disturbance may affect the growth and development of the root system in the later growth stage.In this study,finite element and statistical analysis methods were combined to provide an effective approach for indepth analysis of the biomechanical mechanisms of wind disturbances that inhibit tomato seedlings’growth from the root system’s perspective.展开更多
Polyaspartic acid(PASP)is a nontoxic,biodegradable,environmentally friendly polymer and is widely used as a fertilizer synergist in agricultural production.In many old orchards and vegetable gardens,highly fertile soi...Polyaspartic acid(PASP)is a nontoxic,biodegradable,environmentally friendly polymer and is widely used as a fertilizer synergist in agricultural production.In many old orchards and vegetable gardens,highly fertile soil is often accompanied by severe heavy metal contamination.The present study was designed to investigate mineral element interactions mediated by PASP under copper(Cu)+cadmium(Cd)combined stress to provide reasonable suggestions for scientific fertilization.A pot experiment was conducted in which tomato seedlings served as plant materials.A concentration of 700 mgPASP and foliar spraying application methods were selected based on previous experiments.Four treatments were applied:normal soil(control(CK)),Cu+Cd(combined stress),Cu+Cd+PASP,and normal soil+PASP.The plant biomass,root activity,and mineral elements were measured,and these data were analyzed by Data Processing System(DPS)statistical software.The results showed that,under Cu+Cd combined stress,PASP promoted stem diameter growth,root activity and chlorophyll content and ultimately increased the biomass of tomato seedlings to different degrees.Moreover,the content of both Cu and Cd and their individual accumulation in plants decreased.PASP increased the distribution of Cu and Cd in the roots under Cu+Cd combined stress,and the translocation ability from the roots to shoots was significantly restricted.With respect to essential elements,PASP promoted mainly the absorption and translocation of potassium(K),calcium(Ca),and magnesium(Mg),which greatly exerted physiological roles.However,the variation trends of Cu and Cd under normal soil conditions contrasted with those under stress conditions.With respect to essential elements other than K,Ca,and Mg,PASP mostly restrained their absorption but promoted their translocation.The regulatory mechanism of PASP differed between the combined stress conditions and normal soil conditions.Under the combined stress conditions,PASP seemed to mainly promote these advantageous factors that exert physiological regulatory functions.Under normal soil conditions,PASP mainly acted as a biological stimulant or signaling molecule for increased nutrient efficiency,which caused greater biomass productivity.展开更多
A hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 μmol/L Cd induced a slight increase in plant height of He...A hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 μmol/L Cd induced a slight increase in plant height of Hezuo 903 and the SPAD (the Soil–Plant Analyses Development) value of the 2 cultivars. However, at higher Cd levels, i.e., 1 and 10 μmol/L, root length and volume, plant height, and SPAD value were all significantly reduced. On an average of the 2 cultivars, exposure to 1 and 10 μmol/L Cd for 33 d reduced plant height by 18.9% and 46.4% and SPAD value by 11.2% and 31.6%, compared with control, respectively. Similarly, root length was reduced by 41.1% and 25.8% and root volume by 45.2% and 63.7%, respectively. The addition of Cd in the growth medium also had significant deleterious effect on net photosynthetic rate (Pn) and intracellular CO2 concentration (Ci), with Pn being reduced by 27.2% and 62.1% at 1 μmol/L and 10 μmol/L Cd treatments compared to the control, respectively, while Ci increased correspondingly by 28.4% and 39.3%.展开更多
Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and ana...Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and analyzed them using the technique for order preference by similarity to ideal solution analysis to select the optimal trehalose concentration for treatment. We also determined the contents of sugar and abscisic acid (ABA) and detected the expression of genes involved in the metabolism of sugar and ABA by quantitative real-time PCR. Results showed that the optimal trehalose concentration was 2 mmol/L for tomato seedlings under salt stress. Exogenous trehalose decreased the starch content and increased the soluble sugar con- tent by a ecting the expression of genes related to the metabolism of starch and soluble sugar. Exogenous trehalose altered the accumulation and distribution of sugar by inducing the upregulation of sugar transporter genes. Furthermore, trehalose increased the ABA content to induce salt stress response by regulating the expression of genes related to the synthesis and metabolism of ABA. In conclusion, trehalose can e ectively alleviate salt stress and enhance salt tolerance of tomato. These ndings provide a novel perspective and a better resource to investigate the salt tolerance mechanism and a new method for alleviating salt stress in tomato.展开更多
Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentration...Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2 on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2 (360 or 720μL L-1) and four nutrient solutions of different strengths (1/2-, 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2, and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2 did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2 treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2 concentrations.展开更多
增加的大气的 CO2 集中通常被期望提高农业 C3 蔬菜罪的光合作用和生长，因此导致庄稼产量的增加。然而，很少在植物生长和开发上对提高的 CO2 和 N 种类的联合效果被知道。二个生长房间实验被进行决定 NH4 (+)/NO3 (?) 比率的效果并且...增加的大气的 CO2 集中通常被期望提高农业 C3 蔬菜罪的光合作用和生长，因此导致庄稼产量的增加。然而，很少在植物生长和开发上对提高的 CO2 和 N 种类的联合效果被知道。二个生长房间实验被进行决定 NH4 (+)/NO3 (?) 比率的效果并且在生理的发展和西红柿幼苗的水使用提高了 CO2 集中。西红柿与营养液在生长房间在 NH4 (+)/NO3 (?) 比率和 CO2 集中变化在集装箱为 45 d 被种。结果显示出那植物高度，茎厚度，全部的干燥重量，叶子的干燥重量，茎和根， G 价值(总数种干燥重量/幼苗天)，叶绿素内容，光合的率，叶级、整个的植物级的水使用效率和西红柿幼苗的累积的水消费与在提高的 CO2 处理在营养液增加 NO3 (?)的比例被增加。植物生物资源，植物高度，茎厚度和光合的率比在周围的 CO2 集中在提高的 CO2 集中更高是 67% ， 22% ， 24% 和 55% ，取决于 NH4 (+)/NO3 (?) 比率的价值。这些结果显示那提高的 CO2 集中没减轻 100% NH4 (+)-N 的不利效果(在营养液) 在西红柿幼苗上。在两 CO2 水平，营养液的 NH4 (+)/NO3 (?) 比率强烈几乎影响了植物性能的每项措施，并且硝酸盐美联储植物达到了更大的生物资源生产，作为与铵美联储植物相比。这些现象似乎与光合的率和西红柿幼苗的累积的水消费的协调规定有关。展开更多
Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observati...Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observation. The results showed that under simulated shipping and storage conditions, seedling quality change following different durations (days) of shipping and storage was correlated significantly or even very significantly with certain physiological and morphological indices. With various measured indices following different periods of shipping and storage treatment subjected to multinomial successive regressive correlation analysis, the principal factors influencing seedling quality maintenance level are identified to be chlorophyll content →dry short weight → leaf freshness index in order of their importance. Significance analysis with multinomial fitted equation indicated that correlations between any one of above three factors and the growth index after field planting reached very significant difference level.展开更多
Silicon can improve drought tolerance of plants,but the mechanism still remains unclear.Previous studies have mainly concentrated on silicon-accumulating plants,whereas less work has been conducted in silicon-excludin...Silicon can improve drought tolerance of plants,but the mechanism still remains unclear.Previous studies have mainly concentrated on silicon-accumulating plants,whereas less work has been conducted in silicon-excluding plants,such as tomato(Solanum lycopersicum L.).In this study,we investigated the effects of exogenous silicon(2.5 mmol L^(–1))on the chlorophyll fluorescence and expression of photosynthesis-related genes in tomato seedlings(Zhongza 9)under water stress induced by 10%(w/v)polyethylene glycol(PEG-6000).The results showed that under water stress,the growth of shoot and root was inhibited,and the chlorophyll and carotenoid concentrations were decreased,while silicon addition improved the plant growth and increased the concentrations of chlorophyll and carotenoid.Under water sterss,chlorophyll fluorescence parameters such as PSII maximum photochemical efficiency(F_v/F_m),effective quantum efficiency,actual photochemical quantum efficiency(Ф_(PSII)),photosynthetic electron transport rate(ETR),and photochemical quenching coefficient(q_P)were decreased;while these changes were reversed in the presence of added silicon.The expressions of some photosynthesis-related genes including PetE,PetF,PsbP,PsbQ,PsbW,and Psb28 were down-regulated under water stress,and exogenous Si could partially up-regulate their expressions.These results suggest that silicon plays a role in the alleviation of water stress by modulating some photosynthesis-related genes and regulating the photochemical process,and thus promoting photosynthesis.展开更多
Nitric oxide(NO),a bioactive signaling molecule,serves as an antioxidant and anti-stress agent under abiotic stress.A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside(SNP),a NO d...Nitric oxide(NO),a bioactive signaling molecule,serves as an antioxidant and anti-stress agent under abiotic stress.A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside(SNP),a NO donor,on tomato seedlings exposed to 50 μmol L-1CuCl 2.The results show that copper is primarily stored in the soluble cell sap fraction in the roots,especially after treatment with Cu+SNP treatment,which accounted for 66.2% of the total copper content.The copper concentration gradually decreased from the roots to the leaves.In the leaves,exogenous NO induces the storage of excess copper in the cell walls.Copper stress decreases the proportion of copper integrated with pectates and proteins,but exogenous NO remarkably reverses this trend.The alleviating effect of NO is blocked by hemoglobin.Thus,exogenous NO is likely involved in the regulation of the subcellular copper concentrations and its chemical forms under copper stress.Although exogenous NO inhibited the absorption and transport of excess copper to some extent,the copper accumulation in tomato seedlings significantly increased under copper stress.The use of exogenous NO to enhance copper tolerance in some plants is a promising method for copper remediation.展开更多
The study on raising of strong tomato seedlings in high-temperature season is of great practical significance,because high-temperature condition in summer and autumn causes excessive growth of tomato seedlings easily....The study on raising of strong tomato seedlings in high-temperature season is of great practical significance,because high-temperature condition in summer and autumn causes excessive growth of tomato seedlings easily. ‘Fenniya'variety was selected as an experimental material,an orthogonal experiment was designed with rhizospheric temperature( A),light intensity( B) and nutrient salt concentration( C) as three factors which were designed with three levels,so as to study the effects of different treatments on root activity,strong seedling index,hypocotyl length and average internode length. The results showed that the most important factor for tomato seedling's root activity,hypocotyl length and internode length was nutrient salt concentration. In terms of effect on seedling index,substrate temperature should be reduced properly,to avoid excessive shading. It was primarily determined that the effects of three factors on the raising of strong tomato seedlings ranked as factor C,factor B and factor A from high to low; and the screened optimal seedling raising conditions were the rhizospheric temperature at( 3 + 1)℃,the shading rate of( 50 + 5) % and the EC value of( 5. 0 + 0. 5) mS/cm.展开更多
Blue and red light are spectral wavelengths more effective for plants. The effects of different ratios of red and blue light( R/B = 2,R/B = 4,R/B = 8,R/B = 12) provided by LEDs on morphology and photosynthetic charact...Blue and red light are spectral wavelengths more effective for plants. The effects of different ratios of red and blue light( R/B = 2,R/B = 4,R/B = 8,R/B = 12) provided by LEDs on morphology and photosynthetic characteristics of tomato seedlings were studied. The results showed that plant height,stem diameter,fresh weight,dry weight,seedling index and G value increased with the increase of R/B ratio until 8. On the contrary,SPDA value decreased with the increase of R/B ratio. Photosynthetic characteristics were measured by CO_2 assimilation( Pn),stomatal conductance( gs) and intracellular CO_2 concentration( Ci). Pn and gs decreased with the increase of R/B ratio. Furthermore,similar trend was investigated in photochemical quenching( q P) and electron transport rate( ETR).Results of this study suggest that compared with white LED,appropriate combination of red and blue light can enhance plant growth and photosynthetic characteristics,and the optimal blue/red ratio for tomato growth was R/B = 8.展开更多
The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (PO...The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxide (APX), glutathione reductase (GR), catalase (CAT), the contents of H2O2, ascorbic (AsA) and malondialdehyde (MDA) were studied to investigate how active oxygen damaged the membrane lipid under hypoxia stress. With 10-200 μmol?L-1 Mn2+, the activities of SOD, POD, APX, GR and the contents of H2O2, AsA, MDA of leaves and roots increased significantly, which indicated that low Mn2+ could eliminate the active oxygen and protect the membrane lipid from hurt. But the activities of catalase (CAT) decreased evidently in the root. When the concentration of Mn2+ reached 400-600 μmol?L-1 under hypoxia stress, the activities of SOD, POD, APX, GR and ASA content decreased remarkably. However, the contents of H2O2 and MDA increased contrarily. A series of resistance genes level achieved peak value with 10 μmol?L-1 Mn2+. The expression level of SOD, CAT, APX, POD, GR were 6.28, 2.19, 5.66, 5.21 and 6.79 times compared to control respectively. These results illustrated appropriate amount of Mn2+ could reduce the damage of active oxygen under hypoxia stress, but reversely, high level of Mn2+ just aggravated the already serious damage to the tomato seedlings.展开更多
Utilization of organic nitrogen (N) is an important aspect of plant N assimilation and has potential application in sustainable agriculture. The aim of this study was to investigate the plant growth,C and N accumulati...Utilization of organic nitrogen (N) is an important aspect of plant N assimilation and has potential application in sustainable agriculture. The aim of this study was to investigate the plant growth,C and N accumulation in leaves and roots of tomato seedlings in response to inorganic (NH4+-N,NO3--N) and organic nitrogen (Gly-N). Different forms of nitrogen (NH4+-N,NO3--N,Gly-N) were supplied to two tomato cultivars (Shenfen 918 and Huying 932) using a hydroponics system. The plant dry biomass,chlorophyll content,root activity,total carbon and nitrogen content in roots and leaves,and total N absorption,etc. were assayed during the cultivation. Our results showed that no significant differences in plant height,dry biomass,and total N content were found within the first 16 d among three treatments;however,significant differences in treatments on 24 d and 32 d were observed,and the order was NO3--N > Gly-N > NH4+-N. Significant differences were also observed between the two tomato cultivars. Chlorophyll contents in the two cultivars were significantly increased by the Gly-N treatment,and root activity showed a significant decrease in NH4+-N treatment. Tomato leaf total carbon content was slightly affected by different N forms;however,total carbon in root and total nitrogen in root and leaf were promoted significantly by inorganic and organic N. Among the applied N forms,the increasing effects of the NH4+-N treatment were larger than that of the Gly-N. In a word,different N resources resulted in different physiological effects in tomatoes. Organic nitrogen (e.g.,Gly-N) can be a proper resource of plant N nutrition. Tomatoes of different genotypes had different responses under organic nitrogen (e.g.,Gly-N) supplies.展开更多
Tomato seedlings were used as experimental materials and treated with 1.0,2.0,3.0,and 4.0 mg/L ozone water irrigation and 0.2,0.4,0.6,and 0.8mg/L ozone water spray treatments.Indexes including the malondialdehyde(MDA)...Tomato seedlings were used as experimental materials and treated with 1.0,2.0,3.0,and 4.0 mg/L ozone water irrigation and 0.2,0.4,0.6,and 0.8mg/L ozone water spray treatments.Indexes including the malondialdehyde(MDA)content,superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT),activities,soil and plant analysis development(SPAD)value,and nitrogen content of leaves were measured.Furthermore,the expression of antioxidant enzyme,chlorophyll synthesis and nitrogen absorption genes was analyzed after optimal ozone water treatment.The results showed that the activities of antioxidant enzymes in tomato leaves were significantly increased,and the MDA content in tomato leaves was significantly reduced by ozone water irrigation and spray treatment,which indicated that ozone water treatment can significantly improve the stress tolerance of tomato seedlings.Ozone water irrigation and spraying could also significantly increase the leaf SPAD value and nitrogen content of tomato seedlings,and the optimal concentrations of ozone water irrigation and spraying were 3.0mg/L and 0.6 mg/L,respectively.The effect of ozone water irrigation on improving the physiological characteristics of tomato seedlings was better than that of spraying.After treatment with the optimal concentration of ozone water,the relative expression of antioxidant enzyme,chlorophyll synthesis,and nitrogen absorption genes was significantly increased,and the maximum expression level was reached at 12h.In addition,ozone water irrigation could promote the expression of genes more than ozone water spraying,which was consistent with the improvements in the physiological characteristics of the tomato seedlings.展开更多
This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites ...This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.展开更多
Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic trait.Here,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with s...Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic trait.Here,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato(Solanum lycopersicum).These fruits exhibited a thicker pericarp,undeveloped ovules,and few jelly tissues,leading to smaller locules with empty cavities.Histological investigation showed that GA treatment produced more cell layers with larger cells in the pericarp,suggesting its promotion in both cell division and expansion.Transcriptomic analyses between GA-3and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones,cell division,cell expansion,and transcription factors,implying that they coordinately regulated parthenocarpy conferred by GA.In particular,the downregulation of five reported repressors of tomato parthenocarpy,including two auxin signaling components,AUXIN RESPONSE FACTOR5(SlARF5)and Sl ARF7,and three MADS-box genes,TOMATO APETALA3(TAP3),TOMATO PISTILLATA(TPI),and AGAMOUS-LIKE6(SlAGL6),after GA treatment might play a key role in this process.Furthermore,we found that the knockdown of a GA signaling factor SlMYB33,which was depressed by GA treatment,induced parthenocarpic fruit set in tomato,an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato parthenocarpy.Thus,our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy.展开更多
Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water sh...Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water shortages and the overuse of fertilizers.The field experiment had twelve treatments and a control(CK)trial including two irrigation amounts(I1,100%ETm;I2,60%ETm;where ETm is the maximum evapotranspiration),two nitrogen applications(N1,360 kg ha^(−1);N2,120 kg ha^(−1))and three biochar application levels(B1,60 t ha^(−1);B_(2),30 t ha^(−1)and B3,0 t ha^(−1)).A multi-objective synergistic irrigation-nitrogen-biochar application system for improving tomato yield,quality,water and nitrogen use efficiency,and greenhouse emissions was developed by integrating the techniques of experimentation and optimization.First,a coupled irrigation-nitrogen-biochar plot experiment was arranged.Then,tomato yield and fruit quality parameters were determined experimentally to establish the response relationships between irrigation-nitrogen-biochar dosage and yield,comprehensive quality of tomatoes(TCQ),irrigation water use efficiency(IWUE),partial factor productivity of nitrogen(PFPN),and net greenhouse gas emissions(NGE).Finally,a multi-objective dynamic optimization regulation model of irrigation-nitrogen-biochar resource allocation at different growth stages of tomato was constructed which was solved by the fuzzy programming method.The results showed that the application of irrigation and nitrogen to biochar promoted increase in yield,IWUE and PFPN,while it had an inhibitory effect on NGE.In addition,the optimal allocation amounts of water and fertilizer were different under different scenarios.The yield of the S1 scenario increased by 8.31%compared to the B_(1)I_(1)N_(2) treatment;TCQ of the S2 scenario increased by 5.14%compared to the B_(2)I_(2)N_(1) treatment;IWUE of the S3 scenario increased by 10.01%compared to the B1I2N2 treatment;PFPN of the S4 scenario increased by 9.35%compared to the B_(1)I_(1)N_(2) treatment;and NGE of the S5 scenario decreased by 11.23%compared to the B_(2)I1N1 treatment.The optimization model showed that the coordination of multiple objectives considering yield,TCQ,IWUE,PFPN,and NGE increased on average from 4.44 to 69.02%compared to each treatment when the irrigation-nitrogen-biochar dosage was 205.18 mm,186 kg ha^(−1)and 43.31 t ha^(−1),respectively.This study provides a guiding basis for the sustainable management of water and fertilizer in greenhouse tomato production under drip irrigation fertilization conditions.展开更多
PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic stress.However,there has been very little research on the function of this...PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic stress.However,there has been very little research on the function of this family gene in tomatoes,which limits its application in germplasm resource improvement.Therefore,the PLATZ gene family was identified and analyzed in tomato,and its roles were predicted and verified to provide a basis for in-depth research on SlPLATZ gene function.In this study,the PLATZ family members of tomato were identified in the whole genome,and 19 SlPLATZ genes were obtained.Functional prediction was conducted based on gene and promoter structure analysis and RNA-seq-based expression pattern analysis.SlPLATZ genes that responded significantly under different abiotic stresses or were significantly differentially expressed among multiple tissues were screened as functional gene resources.SlPLATZ17 was selected for functional verification by experiment-based analysis.The results showed that the downregulation of SlPLATZ17 gene expression reduced the drought and salt tolerance of tomato plants.Tomato plants overexpressing SlPLATZ17 had larger flower sizes and long,thin petals,adjacent petals were not connected at the base,and the stamen circumference was smaller.This study contributes to understanding the functions of the SlPLATZ family in tomato and provides a reference for functional gene screening.展开更多
Background Light is a critical factor in plant growth and development,particularly in controlled environments.Light-emitting diodes(LEDs)have become a reliable alternative to conventional high pressure sodium(HSP)lamp...Background Light is a critical factor in plant growth and development,particularly in controlled environments.Light-emitting diodes(LEDs)have become a reliable alternative to conventional high pressure sodium(HSP)lamps because they are more efficient and versatile in light sources.In contrast to well-known specialized LED light spectra for vegetables,the appropriate LED lights for crops such as cotton remain unknown.Results In this growth chamber study,we selected and compared four LED lights with varying percentages(26.44%–68.68%)of red light(R,600–700 nm),combined with other lights,for their effects on growth,leaf anatomy,and photosynthesis of cotton seedlings,using HSP lamp as a control.The total photosynthetic photon flux density(PPFD)was(215±2)μmol·m-2·s-1 for all LEDs and HSP lamp.The results showed significant differences in all tested parameters among lights,and the percentage of far red(FR,701–780 nm)within the range of 3.03%–11.86%was positively correlated with plant growth(characterized by leaf number and area,plant height,stem diameter,and total biomass),palisade layer thickness,photosynthesis rate(Pn),and stomatal conductance(Gs).The ratio of R/FR(4.445–11.497)negatively influenced the growth of cotton seedlings,and blue light(B)suppressed stem elongation but increased palisade cell length,chlorophyll content,and Pn.Conclusion The LED 2 was superior to other LED lights and HSP lamp.It had the highest ratio of FR within the total PPFD(11.86%)and the lowest ratio of R/FR(4.445).LED 2 may therefore be used to replace HPS lamp under controlled environments for the study of cotton at the seedling stage.展开更多
基金supported by a European Marie Curie International Incoming Fellowship(326847 and 912847)a Chinese Universities Scientific Fund(2452018313)+1 种基金a High-End Foreign Expert Recruitment Program(G2022172006L)an Agricultural Science Innovation and Transformation Project of Shaanxi Province(NYKJ-2022-YL(XN)12).
文摘Wind disturbance as a green method can effectively prevent the overgrowth of tomato seedlings,and its mechanism may be related to root system mechanics.This study characterized the biophysical mechanical properties of taproot and lateral roots of tomato seedlings at five seedling ages and seedling substrates with three different moisture content.The corresponding root system-substrate finite element(FE)model was then developed and validated.The study showed that seedling age significantly affected the biomechanical properties of the taproot and lateral roots of the seedlings and that moisture content significantly affected the biomechanical properties of the seedling substrate(p<0.05).The established FE model was sensitive to wind speed,substrate moisture content,strong seedling index,and seedling age and was robust.The multiple linear regression equations obtained could predict the maximum stress and strain of the root system of tomato seedlings in the wind field.The strong seedling index had the greatest impact on the biomechanical response of the seedling root system during wind disturbance,followed by wind speed.In contrast,seedling age had no significant effect on the biomechanical response of the root system during wind disturbance.In the simulation,no mechanical damage was observed on the tissue of the seedling root system,but there were some strain behaviors.Based on the plant stress resistance,wind disturbance may affect the growth and development of the root system in the later growth stage.In this study,finite element and statistical analysis methods were combined to provide an effective approach for indepth analysis of the biomechanical mechanisms of wind disturbances that inhibit tomato seedlings’growth from the root system’s perspective.
基金supported by the Project of Shandong Province Higher Educational Science and Technology Program,China(J16LF02)the Funds of Shandong"Double Tops"Program,China(SYL2017YSTD01)the Major Scientific and Technological Innovation Project in Shandong Province,China(2018CXGC0209)
文摘Polyaspartic acid(PASP)is a nontoxic,biodegradable,environmentally friendly polymer and is widely used as a fertilizer synergist in agricultural production.In many old orchards and vegetable gardens,highly fertile soil is often accompanied by severe heavy metal contamination.The present study was designed to investigate mineral element interactions mediated by PASP under copper(Cu)+cadmium(Cd)combined stress to provide reasonable suggestions for scientific fertilization.A pot experiment was conducted in which tomato seedlings served as plant materials.A concentration of 700 mgPASP and foliar spraying application methods were selected based on previous experiments.Four treatments were applied:normal soil(control(CK)),Cu+Cd(combined stress),Cu+Cd+PASP,and normal soil+PASP.The plant biomass,root activity,and mineral elements were measured,and these data were analyzed by Data Processing System(DPS)statistical software.The results showed that,under Cu+Cd combined stress,PASP promoted stem diameter growth,root activity and chlorophyll content and ultimately increased the biomass of tomato seedlings to different degrees.Moreover,the content of both Cu and Cd and their individual accumulation in plants decreased.PASP increased the distribution of Cu and Cd in the roots under Cu+Cd combined stress,and the translocation ability from the roots to shoots was significantly restricted.With respect to essential elements,PASP promoted mainly the absorption and translocation of potassium(K),calcium(Ca),and magnesium(Mg),which greatly exerted physiological roles.However,the variation trends of Cu and Cd under normal soil conditions contrasted with those under stress conditions.With respect to essential elements other than K,Ca,and Mg,PASP mostly restrained their absorption but promoted their translocation.The regulatory mechanism of PASP differed between the combined stress conditions and normal soil conditions.Under the combined stress conditions,PASP seemed to mainly promote these advantageous factors that exert physiological regulatory functions.Under normal soil conditions,PASP mainly acted as a biological stimulant or signaling molecule for increased nutrient efficiency,which caused greater biomass productivity.
基金Project (No. M303355) supported by the Natural Science Foundation of Zhejiang Province, China
文摘A hydroponic experiment carried out to study the effect of five Cd levels on growth and photosynthesis of two tomato cultivars showed that the addition of 0.1 μmol/L Cd induced a slight increase in plant height of Hezuo 903 and the SPAD (the Soil–Plant Analyses Development) value of the 2 cultivars. However, at higher Cd levels, i.e., 1 and 10 μmol/L, root length and volume, plant height, and SPAD value were all significantly reduced. On an average of the 2 cultivars, exposure to 1 and 10 μmol/L Cd for 33 d reduced plant height by 18.9% and 46.4% and SPAD value by 11.2% and 31.6%, compared with control, respectively. Similarly, root length was reduced by 41.1% and 25.8% and root volume by 45.2% and 63.7%, respectively. The addition of Cd in the growth medium also had significant deleterious effect on net photosynthetic rate (Pn) and intracellular CO2 concentration (Ci), with Pn being reduced by 27.2% and 62.1% at 1 μmol/L and 10 μmol/L Cd treatments compared to the control, respectively, while Ci increased correspondingly by 28.4% and 39.3%.
基金supported by the National Natural Science Foundation of China (Nos. 31671899 and 31871848)
文摘Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and analyzed them using the technique for order preference by similarity to ideal solution analysis to select the optimal trehalose concentration for treatment. We also determined the contents of sugar and abscisic acid (ABA) and detected the expression of genes involved in the metabolism of sugar and ABA by quantitative real-time PCR. Results showed that the optimal trehalose concentration was 2 mmol/L for tomato seedlings under salt stress. Exogenous trehalose decreased the starch content and increased the soluble sugar con- tent by a ecting the expression of genes related to the metabolism of starch and soluble sugar. Exogenous trehalose altered the accumulation and distribution of sugar by inducing the upregulation of sugar transporter genes. Furthermore, trehalose increased the ABA content to induce salt stress response by regulating the expression of genes related to the synthesis and metabolism of ABA. In conclusion, trehalose can e ectively alleviate salt stress and enhance salt tolerance of tomato. These ndings provide a novel perspective and a better resource to investigate the salt tolerance mechanism and a new method for alleviating salt stress in tomato.
基金Project supported by the National Natural Science Foundation of China (No. 30230250).
文摘Exposing tomato seedlings to elevated CO2 concentrations may have potentially profound impacts on the tomato yield and quality. A growth chamber experiment was designed to estimate how different nutrient concentrations influenced the effect of elevated CO2 on the growth and nutrient uptake of tomato seedlings. Tomato (Hezuo 906) was grown in pots placed in controlled growth chambers and was subjected to ambient or elevated CO2 (360 or 720μL L-1) and four nutrient solutions of different strengths (1/2-, 1/4-, 1/8-, and 1/16-strength Japan Yamazaki nutrient solutions) in a completely randomized design. The results indicated that some agricultural characteristics of the tomato seedlings such as the plant height, stem thickness, total dry and fresh weights of the leaves, stems and roots, the G value (G value = total plant dry weight/seedling age), and the seedling vigor index (seedling vigor index = stem thickness/(plant height×total plant dry weight) increased with the elevated CO2, and the increases were strongly dependent on the nutrient solution concentrations, being greater with higher nutrient solution concentrations. The elevated CO2 did not alter the ratio of root to shoot. The total N, P, K, and C absorbed from all the solutions except P in the 1/8- and 1/16-strength nutrient solutions increased in the elevated CO2 treatment. These results demonstrate that the nutrient demands of the tomato seedlings increased at elevated CO2 concentrations.
基金Project supported by the National Natural Science Foundation of China(No.30230250).
文摘增加的大气的 CO2 集中通常被期望提高农业 C3 蔬菜罪的光合作用和生长，因此导致庄稼产量的增加。然而，很少在植物生长和开发上对提高的 CO2 和 N 种类的联合效果被知道。二个生长房间实验被进行决定 NH4 (+)/NO3 (?) 比率的效果并且在生理的发展和西红柿幼苗的水使用提高了 CO2 集中。西红柿与营养液在生长房间在 NH4 (+)/NO3 (?) 比率和 CO2 集中变化在集装箱为 45 d 被种。结果显示出那植物高度，茎厚度，全部的干燥重量，叶子的干燥重量，茎和根， G 价值(总数种干燥重量/幼苗天)，叶绿素内容，光合的率，叶级、整个的植物级的水使用效率和西红柿幼苗的累积的水消费与在提高的 CO2 处理在营养液增加 NO3 (?)的比例被增加。植物生物资源，植物高度，茎厚度和光合的率比在周围的 CO2 集中在提高的 CO2 集中更高是 67% ， 22% ， 24% 和 55% ，取决于 NH4 (+)/NO3 (?) 比率的价值。这些结果显示那提高的 CO2 集中没减轻 100% NH4 (+)-N 的不利效果(在营养液) 在西红柿幼苗上。在两 CO2 水平，营养液的 NH4 (+)/NO3 (?) 比率强烈几乎影响了植物性能的每项措施，并且硝酸盐美联储植物达到了更大的生物资源生产，作为与铵美联储植物相比。这些现象似乎与光合的率和西红柿幼苗的累积的水消费的协调规定有关。
基金This is a major research program assigned and financed by the National High-Technology R&D Program(863 Plan)(2004AA247010)is also a major research project(2001BA503B)for the 10th Five-year Plan period approved and funded by the Ministry of Science and Technology,.P.R.China.
文摘Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observation. The results showed that under simulated shipping and storage conditions, seedling quality change following different durations (days) of shipping and storage was correlated significantly or even very significantly with certain physiological and morphological indices. With various measured indices following different periods of shipping and storage treatment subjected to multinomial successive regressive correlation analysis, the principal factors influencing seedling quality maintenance level are identified to be chlorophyll content →dry short weight → leaf freshness index in order of their importance. Significance analysis with multinomial fitted equation indicated that correlations between any one of above three factors and the growth index after field planting reached very significant difference level.
基金funded by the National Natural Science Foundation of China (31501750, 31501807, 31471866, 31772290)
文摘Silicon can improve drought tolerance of plants,but the mechanism still remains unclear.Previous studies have mainly concentrated on silicon-accumulating plants,whereas less work has been conducted in silicon-excluding plants,such as tomato(Solanum lycopersicum L.).In this study,we investigated the effects of exogenous silicon(2.5 mmol L^(–1))on the chlorophyll fluorescence and expression of photosynthesis-related genes in tomato seedlings(Zhongza 9)under water stress induced by 10%(w/v)polyethylene glycol(PEG-6000).The results showed that under water stress,the growth of shoot and root was inhibited,and the chlorophyll and carotenoid concentrations were decreased,while silicon addition improved the plant growth and increased the concentrations of chlorophyll and carotenoid.Under water sterss,chlorophyll fluorescence parameters such as PSII maximum photochemical efficiency(F_v/F_m),effective quantum efficiency,actual photochemical quantum efficiency(Ф_(PSII)),photosynthetic electron transport rate(ETR),and photochemical quenching coefficient(q_P)were decreased;while these changes were reversed in the presence of added silicon.The expressions of some photosynthesis-related genes including PetE,PetF,PsbP,PsbQ,PsbW,and Psb28 were down-regulated under water stress,and exogenous Si could partially up-regulate their expressions.These results suggest that silicon plays a role in the alleviation of water stress by modulating some photosynthesis-related genes and regulating the photochemical process,and thus promoting photosynthesis.
基金supported partially by the National Natural Science Foundation of China (31201619)Profession Expert Group of Facility Cultivation and Engineering (CARS25-D-03)the Sci-Tech Development Project of Tai’an City, China (32606)
文摘Nitric oxide(NO),a bioactive signaling molecule,serves as an antioxidant and anti-stress agent under abiotic stress.A hydroponics experiment was conducted to investigate the effects of sodium nitroprusside(SNP),a NO donor,on tomato seedlings exposed to 50 μmol L-1CuCl 2.The results show that copper is primarily stored in the soluble cell sap fraction in the roots,especially after treatment with Cu+SNP treatment,which accounted for 66.2% of the total copper content.The copper concentration gradually decreased from the roots to the leaves.In the leaves,exogenous NO induces the storage of excess copper in the cell walls.Copper stress decreases the proportion of copper integrated with pectates and proteins,but exogenous NO remarkably reverses this trend.The alleviating effect of NO is blocked by hemoglobin.Thus,exogenous NO is likely involved in the regulation of the subcellular copper concentrations and its chemical forms under copper stress.Although exogenous NO inhibited the absorption and transport of excess copper to some extent,the copper accumulation in tomato seedlings significantly increased under copper stress.The use of exogenous NO to enhance copper tolerance in some plants is a promising method for copper remediation.
基金Supported by Special Funding Project for the Construction of Henan Modern Agricultural Industrial Technology System(S2010-03)
文摘The study on raising of strong tomato seedlings in high-temperature season is of great practical significance,because high-temperature condition in summer and autumn causes excessive growth of tomato seedlings easily. ‘Fenniya'variety was selected as an experimental material,an orthogonal experiment was designed with rhizospheric temperature( A),light intensity( B) and nutrient salt concentration( C) as three factors which were designed with three levels,so as to study the effects of different treatments on root activity,strong seedling index,hypocotyl length and average internode length. The results showed that the most important factor for tomato seedling's root activity,hypocotyl length and internode length was nutrient salt concentration. In terms of effect on seedling index,substrate temperature should be reduced properly,to avoid excessive shading. It was primarily determined that the effects of three factors on the raising of strong tomato seedlings ranked as factor C,factor B and factor A from high to low; and the screened optimal seedling raising conditions were the rhizospheric temperature at( 3 + 1)℃,the shading rate of( 50 + 5) % and the EC value of( 5. 0 + 0. 5) mS/cm.
基金Supported by Shanghai Science and Technology Commission Project,China(14DZ1206303)National Key Technology R&D Program(2014BAD05B05-05)Shanghai Agriculture Applied Technology Development Program,China(Grant No.20170201)
文摘Blue and red light are spectral wavelengths more effective for plants. The effects of different ratios of red and blue light( R/B = 2,R/B = 4,R/B = 8,R/B = 12) provided by LEDs on morphology and photosynthetic characteristics of tomato seedlings were studied. The results showed that plant height,stem diameter,fresh weight,dry weight,seedling index and G value increased with the increase of R/B ratio until 8. On the contrary,SPDA value decreased with the increase of R/B ratio. Photosynthetic characteristics were measured by CO_2 assimilation( Pn),stomatal conductance( gs) and intracellular CO_2 concentration( Ci). Pn and gs decreased with the increase of R/B ratio. Furthermore,similar trend was investigated in photochemical quenching( q P) and electron transport rate( ETR).Results of this study suggest that compared with white LED,appropriate combination of red and blue light can enhance plant growth and photosynthetic characteristics,and the optimal blue/red ratio for tomato growth was R/B = 8.
文摘The changes of antioxidant enzyme activities and related genes expression of tomato seedlings were evaluated under hypoxia stress with different levels of Mn2+. Activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxide (APX), glutathione reductase (GR), catalase (CAT), the contents of H2O2, ascorbic (AsA) and malondialdehyde (MDA) were studied to investigate how active oxygen damaged the membrane lipid under hypoxia stress. With 10-200 μmol?L-1 Mn2+, the activities of SOD, POD, APX, GR and the contents of H2O2, AsA, MDA of leaves and roots increased significantly, which indicated that low Mn2+ could eliminate the active oxygen and protect the membrane lipid from hurt. But the activities of catalase (CAT) decreased evidently in the root. When the concentration of Mn2+ reached 400-600 μmol?L-1 under hypoxia stress, the activities of SOD, POD, APX, GR and ASA content decreased remarkably. However, the contents of H2O2 and MDA increased contrarily. A series of resistance genes level achieved peak value with 10 μmol?L-1 Mn2+. The expression level of SOD, CAT, APX, POD, GR were 6.28, 2.19, 5.66, 5.21 and 6.79 times compared to control respectively. These results illustrated appropriate amount of Mn2+ could reduce the damage of active oxygen under hypoxia stress, but reversely, high level of Mn2+ just aggravated the already serious damage to the tomato seedlings.
基金funded by the National High Technol-ogy Research and Development Program of China (863 Program,2006AA10Z221)China Postdoctoral Science Foundation (2005038436)+1 种基金Shanghai Leading Academic Discipline Project (B209)National Key Technologies R&D Program of China during the 11th Five-Year Plan period (2008BADA7B00 2008BADA7B01)
文摘Utilization of organic nitrogen (N) is an important aspect of plant N assimilation and has potential application in sustainable agriculture. The aim of this study was to investigate the plant growth,C and N accumulation in leaves and roots of tomato seedlings in response to inorganic (NH4+-N,NO3--N) and organic nitrogen (Gly-N). Different forms of nitrogen (NH4+-N,NO3--N,Gly-N) were supplied to two tomato cultivars (Shenfen 918 and Huying 932) using a hydroponics system. The plant dry biomass,chlorophyll content,root activity,total carbon and nitrogen content in roots and leaves,and total N absorption,etc. were assayed during the cultivation. Our results showed that no significant differences in plant height,dry biomass,and total N content were found within the first 16 d among three treatments;however,significant differences in treatments on 24 d and 32 d were observed,and the order was NO3--N > Gly-N > NH4+-N. Significant differences were also observed between the two tomato cultivars. Chlorophyll contents in the two cultivars were significantly increased by the Gly-N treatment,and root activity showed a significant decrease in NH4+-N treatment. Tomato leaf total carbon content was slightly affected by different N forms;however,total carbon in root and total nitrogen in root and leaf were promoted significantly by inorganic and organic N. Among the applied N forms,the increasing effects of the NH4+-N treatment were larger than that of the Gly-N. In a word,different N resources resulted in different physiological effects in tomatoes. Organic nitrogen (e.g.,Gly-N) can be a proper resource of plant N nutrition. Tomatoes of different genotypes had different responses under organic nitrogen (e.g.,Gly-N) supplies.
基金The authors would like to acknowledge the financial support from the Shandong Provincial Key R&D Project of China(2016GNC111013).
文摘Tomato seedlings were used as experimental materials and treated with 1.0,2.0,3.0,and 4.0 mg/L ozone water irrigation and 0.2,0.4,0.6,and 0.8mg/L ozone water spray treatments.Indexes including the malondialdehyde(MDA)content,superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT),activities,soil and plant analysis development(SPAD)value,and nitrogen content of leaves were measured.Furthermore,the expression of antioxidant enzyme,chlorophyll synthesis and nitrogen absorption genes was analyzed after optimal ozone water treatment.The results showed that the activities of antioxidant enzymes in tomato leaves were significantly increased,and the MDA content in tomato leaves was significantly reduced by ozone water irrigation and spray treatment,which indicated that ozone water treatment can significantly improve the stress tolerance of tomato seedlings.Ozone water irrigation and spraying could also significantly increase the leaf SPAD value and nitrogen content of tomato seedlings,and the optimal concentrations of ozone water irrigation and spraying were 3.0mg/L and 0.6 mg/L,respectively.The effect of ozone water irrigation on improving the physiological characteristics of tomato seedlings was better than that of spraying.After treatment with the optimal concentration of ozone water,the relative expression of antioxidant enzyme,chlorophyll synthesis,and nitrogen absorption genes was significantly increased,and the maximum expression level was reached at 12h.In addition,ozone water irrigation could promote the expression of genes more than ozone water spraying,which was consistent with the improvements in the physiological characteristics of the tomato seedlings.
基金based on studies conducted under a governmental request to“Northern Research Institute of Forestry”for performance of applied research within the remit of the Federal Forestry Agency.Project registration No.122020100319-9。
文摘This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.
基金supported by the Key Program of Natural Science Basic Research Plan in Shaanxi Province of China(Grant No.2021JZ-13)。
文摘Gibberellin(GA)is one of the major plant hormones that promote parthenocarpy,a highly valuable agronomic trait.Here,we demonstrated that exogenous GA3application triggered the formation of parthenocarpic fruits with smaller size but unchanged shape in tomato(Solanum lycopersicum).These fruits exhibited a thicker pericarp,undeveloped ovules,and few jelly tissues,leading to smaller locules with empty cavities.Histological investigation showed that GA treatment produced more cell layers with larger cells in the pericarp,suggesting its promotion in both cell division and expansion.Transcriptomic analyses between GA-3and mock-treated unpollinated ovaries/fruits identified a large number of differentially expressed genes related to hormones,cell division,cell expansion,and transcription factors,implying that they coordinately regulated parthenocarpy conferred by GA.In particular,the downregulation of five reported repressors of tomato parthenocarpy,including two auxin signaling components,AUXIN RESPONSE FACTOR5(SlARF5)and Sl ARF7,and three MADS-box genes,TOMATO APETALA3(TAP3),TOMATO PISTILLATA(TPI),and AGAMOUS-LIKE6(SlAGL6),after GA treatment might play a key role in this process.Furthermore,we found that the knockdown of a GA signaling factor SlMYB33,which was depressed by GA treatment,induced parthenocarpic fruit set in tomato,an effect that might have been achieved by enhancing GA biosynthesis and decreasing the expression of some repressors of tomato parthenocarpy.Thus,our results provide a basis for understanding the regulatory mechanism of GA in tomato parthenocarpy.
基金supported by the National Natural Science Foundation of China(52222902 and 52079029)。
文摘Integrated water and fertilizer management is important for promoting sustainable development of facility agriculture,and biochar plays an important role in guaranteeing food production,as well as alleviating water shortages and the overuse of fertilizers.The field experiment had twelve treatments and a control(CK)trial including two irrigation amounts(I1,100%ETm;I2,60%ETm;where ETm is the maximum evapotranspiration),two nitrogen applications(N1,360 kg ha^(−1);N2,120 kg ha^(−1))and three biochar application levels(B1,60 t ha^(−1);B_(2),30 t ha^(−1)and B3,0 t ha^(−1)).A multi-objective synergistic irrigation-nitrogen-biochar application system for improving tomato yield,quality,water and nitrogen use efficiency,and greenhouse emissions was developed by integrating the techniques of experimentation and optimization.First,a coupled irrigation-nitrogen-biochar plot experiment was arranged.Then,tomato yield and fruit quality parameters were determined experimentally to establish the response relationships between irrigation-nitrogen-biochar dosage and yield,comprehensive quality of tomatoes(TCQ),irrigation water use efficiency(IWUE),partial factor productivity of nitrogen(PFPN),and net greenhouse gas emissions(NGE).Finally,a multi-objective dynamic optimization regulation model of irrigation-nitrogen-biochar resource allocation at different growth stages of tomato was constructed which was solved by the fuzzy programming method.The results showed that the application of irrigation and nitrogen to biochar promoted increase in yield,IWUE and PFPN,while it had an inhibitory effect on NGE.In addition,the optimal allocation amounts of water and fertilizer were different under different scenarios.The yield of the S1 scenario increased by 8.31%compared to the B_(1)I_(1)N_(2) treatment;TCQ of the S2 scenario increased by 5.14%compared to the B_(2)I_(2)N_(1) treatment;IWUE of the S3 scenario increased by 10.01%compared to the B1I2N2 treatment;PFPN of the S4 scenario increased by 9.35%compared to the B_(1)I_(1)N_(2) treatment;and NGE of the S5 scenario decreased by 11.23%compared to the B_(2)I1N1 treatment.The optimization model showed that the coordination of multiple objectives considering yield,TCQ,IWUE,PFPN,and NGE increased on average from 4.44 to 69.02%compared to each treatment when the irrigation-nitrogen-biochar dosage was 205.18 mm,186 kg ha^(−1)and 43.31 t ha^(−1),respectively.This study provides a guiding basis for the sustainable management of water and fertilizer in greenhouse tomato production under drip irrigation fertilization conditions.
基金support from the National Natural Science Foundation of China(32102390 and 32072589)the China Agriculture Research System(CARS-23-A11)+1 种基金the Heilongjiang Provincial Natural Science Foundation of China(YQ2021C013)the Northeast Agricultural University Scholars Program(20XG28),China。
文摘PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic stress.However,there has been very little research on the function of this family gene in tomatoes,which limits its application in germplasm resource improvement.Therefore,the PLATZ gene family was identified and analyzed in tomato,and its roles were predicted and verified to provide a basis for in-depth research on SlPLATZ gene function.In this study,the PLATZ family members of tomato were identified in the whole genome,and 19 SlPLATZ genes were obtained.Functional prediction was conducted based on gene and promoter structure analysis and RNA-seq-based expression pattern analysis.SlPLATZ genes that responded significantly under different abiotic stresses or were significantly differentially expressed among multiple tissues were screened as functional gene resources.SlPLATZ17 was selected for functional verification by experiment-based analysis.The results showed that the downregulation of SlPLATZ17 gene expression reduced the drought and salt tolerance of tomato plants.Tomato plants overexpressing SlPLATZ17 had larger flower sizes and long,thin petals,adjacent petals were not connected at the base,and the stamen circumference was smaller.This study contributes to understanding the functions of the SlPLATZ family in tomato and provides a reference for functional gene screening.
基金funded by the China Agriculture Research System(CARS-15-16).
文摘Background Light is a critical factor in plant growth and development,particularly in controlled environments.Light-emitting diodes(LEDs)have become a reliable alternative to conventional high pressure sodium(HSP)lamps because they are more efficient and versatile in light sources.In contrast to well-known specialized LED light spectra for vegetables,the appropriate LED lights for crops such as cotton remain unknown.Results In this growth chamber study,we selected and compared four LED lights with varying percentages(26.44%–68.68%)of red light(R,600–700 nm),combined with other lights,for their effects on growth,leaf anatomy,and photosynthesis of cotton seedlings,using HSP lamp as a control.The total photosynthetic photon flux density(PPFD)was(215±2)μmol·m-2·s-1 for all LEDs and HSP lamp.The results showed significant differences in all tested parameters among lights,and the percentage of far red(FR,701–780 nm)within the range of 3.03%–11.86%was positively correlated with plant growth(characterized by leaf number and area,plant height,stem diameter,and total biomass),palisade layer thickness,photosynthesis rate(Pn),and stomatal conductance(Gs).The ratio of R/FR(4.445–11.497)negatively influenced the growth of cotton seedlings,and blue light(B)suppressed stem elongation but increased palisade cell length,chlorophyll content,and Pn.Conclusion The LED 2 was superior to other LED lights and HSP lamp.It had the highest ratio of FR within the total PPFD(11.86%)and the lowest ratio of R/FR(4.445).LED 2 may therefore be used to replace HPS lamp under controlled environments for the study of cotton at the seedling stage.
