Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary ...Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019.The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status.Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvesting, the timely application of nitrogen fertilizer is fundamental,coupled with moderate field drying for root-vigor preservation and tiller promotion before and after the mechanical harvesting of the main crop.展开更多
The study being the first of its kind established an efficient protocol for micropropagation of Cryptolepis sanguinolenta, an important endangered medicinal plant species, used in the treatment of Malaria. For shoot i...The study being the first of its kind established an efficient protocol for micropropagation of Cryptolepis sanguinolenta, an important endangered medicinal plant species, used in the treatment of Malaria. For shoot induction, semi hard wood nodal segments were maintained on MS (Murashige and Skoog) nutrient medium supplemented with MS vitamins, 30 g/L sucrose, 3% gelrite and various auxin and cytokinin combinations. Treatments involved 6-benzyladenine (BA) at 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0 mg/L in combination with 0.1 mg/L Indole 3-butyric acid (IBA) or Naphthaleneacetic acid (NAA). Control consisted of hormone free MS medium. BA and IBA combinations were found to be more efficient in shoot regeneration than the BA and NAA combinations. Cultures maintained on MS medium supplemented with 3 mg/L BA, in combination with 0.1 mg/L IBA recorded the highest shoot induction (100%), mean shoot length (1.28 cm) and mean number of nodes per explant (2.5). This, however, did not differ significantly from cultures maintained on 2 or 2.5 mg/L BA and 0.1 mg/L IBA supplemented MS medium. Regenerated shoots were transferred onto different media for root induction. Treatments consisted of full strength MS medium augmented with either 0.5 or 0.1 mg/L IBA, hormone free half strength MS medium and half strength MS medium augmented with 0.01 mg/L IBA. After six weeks of culture, no rooting was recorded in all treatments with the exception of half strength MS medium supplemented with 0.01 mg/L IBA, which recorded 60% rooting. Regenerated plantlets were successfully weaned and established in the greenhouse.展开更多
Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids a...Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry.展开更多
North Africa is one of the most regions impacted by water shortage.The implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the neg...North Africa is one of the most regions impacted by water shortage.The implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the negative impact of water shortage.This study investigated the impacts of CD at different levels on drainage outflow,water table level,nitrate loss,grain yield,and water use efficiency(WUE)of various wheat cultivars.Two levels of CD,i.e.,0.4 m below the soil surface(CD-0.4)and 0.8 m below the soil surface(CD-0.8),were compared with subsurface free drainage(SFD)at 1.2 m below the soil surface(SFD-1.2).Under each drainage treatment,four wheat cultivars were grown for two growing seasons(November 2018–April 2019 and November 2019–April 2020).Compared with SFD-1.2,CD-0.4 and CD-0.8 decreased irrigation water by 42.0%and 19.9%,drainage outflow by 40.3%and 27.3%,and nitrate loss by 35.3%and 20.8%,respectively.Under CD treatments,plants absorbed a significant portion of their evapotranspiration from shallow groundwater(22.0%and 8.0%for CD-0.4 and CD-0.8,respectively).All wheat cultivars positively responded to CD treatments,and the highest grain yield and straw yield were obtained under CD-0.4 treatment.Using the initial soil salinity as a reference,the soil salinity under CD-0.4 treatment increased two-fold by the end of the second growing season without negative impacts on wheat yield.Modifying the drainage system by raising the outlet elevation and considering shallow groundwater contribution to crop evapotranspiration promoted water-saving and WUE.Different responses could be obtained based on the different plant tolerance to salinity and water stress,crop characteristics,and growth stage.Site-specific soil salinity management practices will be required to avoid soil salinization due to the adoption of long-term shallow groundwater in Egypt and other similar agroecosystems.展开更多
Sweetpotato is an important crop for food security in many developing countries which is cultivated using vine cuttings. Studies have revealed that there are at least fifteen well characterized viruses known to infect...Sweetpotato is an important crop for food security in many developing countries which is cultivated using vine cuttings. Studies have revealed that there are at least fifteen well characterized viruses known to infect sweetpotato of which 10 are economically important that contribute to yield reduction. Planting materials use by farmers are often infected by one or more of these viruses. The aim of this study was to evaluate three different sources of planting materials of different health status for their field performance and virus presence. The sources of planting materials were in vitro generated platelets, symptomless Field materials and Farmer’s materials. Four sweetpotato varieties Apomuden, Bohye, Ligri and Dadanyuie were selected from each source of planting material. The trial was laid in a split plot design with the sources of planting material allocated to main plots and the varieties to sub-plots. The plantlets of the four varieties were planted at Botanga Irrigation Scheme in Northern region of Ghana. Viral symptom scores were taken twice, score 1 being the average from 4 - 7 weeks after planting (WAP) and score 2 being the average from 8 - 11 WAP. Nitrocellulose Membranes Enzyme Linked Immunosorbent Assay (NCM-ELISA) kits were employed for the detection of sweetpotato viruses on the field. The source of planting materials significantly influenced (P In vitro generated material showed the least symptoms of virus followed by Field materials. Apomuden and Bohye varieties recorded the highest virus score in the first and second virus symptom observational score respectively. NCM-ELISA revealed that the viruses SPFMV, SPMMV, SPMSV, SPCFV, SPCSV, and CMV were significantly present among the different sources of planting materials. In vitro, Field and Farmer materials recorded NCM-ELISA score of 0.225, 1.075 and 1.500 respectively. Apomuden variety recorded the highest virus score in the assay. Vine and root yield was higher among the in vitro generated material. Farmers should use laboratory cleaned material however, in the absence of such material they should select field material showing no symptom of virus.展开更多
The stability of soybean(Glycine max L.Merrill)oil is determined mainly by its fatty acid(FA)composition.We evaluated the FA composition of 1025 Chinese soybean accessions collected from diverse ecoregions and grown i...The stability of soybean(Glycine max L.Merrill)oil is determined mainly by its fatty acid(FA)composition.We evaluated the FA composition of 1025 Chinese soybean accessions collected from diverse ecoregions and grown in multiple locations and years.We observed highly significant differences(P<0.001)between accessions in palmitic acid(PA),stearic acid(SA),oleic acid(OA),linoleic acid(LA),and linolenic acid(LNA)contents.Growth year affected(P<0.001)the abundance of all FAs except PA.The mean PA,SA,OA,LA,and LNA contents were 12.2%,3.8%,21.5%,54.2%,and 8.3%,respectively.The geographical origin of the accession influenced seed FA composition,indicating that accessions originating in each ecoregion tend to have distinct FA composition.We observed significant positive correlations among the three locations and between the two years,suggesting the high heritability and stability of individual accessions across contrasting environments.We also observed a relatively high negative correlation between the contents of OA and both LA and LNA(r=-0.90 and-0.59,respectively,each significant at P<0.001),providing a potential entry point for developing strains producing oil with higher OA and lower LA and LNA levels.These would be appropriate for specialized use in the food industry.Our results will be useful in breeding soybean with improved quality to meet human nutritional and industrial needs.展开更多
The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with ...The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with high nutrient content. The purpose of this study was to assess the effects of foliar applications of calcium and molybdenum on yield and seed physiological potential in common bean plants. A randomized block design was implemented, with the treatments fixed in a factorial scheme: two molybdenum rates (with or without) and four calcium rates, with four replications. The calcium rates applied on the leaves were 0, 150, 300 and 600 g·ha-1 for the first year of the investigation (2005) and 0, 300, 600 and 900 g·ha-1 for the second year (2006). In both years, the molybdenum rates applied on the leaves were 0 g·ha-1 (without) and 75 g·ha-1 (with). The results showed that the foliar calcium application, with or without molybdenum, did not improve yield. Foliar application of calcium alone improved seed physiological potential in common bean plants when applied at the full bloom stage.展开更多
Tissue culture (TC) banana plantlets at the in vitro stage are delicate and devoid of microbes and nutrients that are essential for establishment and subsequent growth. Some microbes are known for function best under ...Tissue culture (TC) banana plantlets at the in vitro stage are delicate and devoid of microbes and nutrients that are essential for establishment and subsequent growth. Some microbes are known for function best under certain soil threshold levels of macro and micronutrients and have been associated with growth and performance of TC banana. A green house and field study was conducted to evaluate the effect of combining two commercial biological products [Rhizatech and ECO-T (mycorrhiza and Trichoderma based products, respectively)] with various sources of nitrogen and phosphorous including Mavuno, Minjingu phosphate rock, Calcium Ammonium Nitrate (CAN), manure and diammonium phosphate (DAP) on growth and performance of TC banana in Vertisol and Rhodic Ferralsol soil conditions. Tissue culture plants were initially inoculated with Rhizatech and ECO-T at the acclimatization stage and subsequently at the beginning of the potting stage and field establishment. Addition of nutrient sources was also done at the same stages of plant growth by mixing with the soil substrates prior to planting. The performance of plants was significantly (at p ≤ 0.05) affected by the combinations of nutrient sources depending on the soil type and stage of plant development. The growth of plants in the Vertisol increased with Trichoderma combined with either organic manure, DAP or combined with a macro and micro nutrient source (Mavuno) as compared to the sole application of Trichoderma. Performance of plants treated with combination of mycorrhiza and either Mavuno and minjigu rock phosphate was consistently higher in the Rhodic Ferralsol than either mycorrhiza alone or fertilizer alone. This indicates that TC plants could highly benefit from combined application of microbiological products and inorganic and organic fertilizers. However, a prior knowledge of the product’s microbial formulation and prevailing soil conditions is essential for optimizing the potential benefits of integrating microbe-based product with inorganic and organic fertilizers.展开更多
Hybrid necrosis is the gradual premature death of leaves or plants in certain F1 hybrids of wheat (Triticum aestivum L.). Comparison of protein expression in necrotic and normal wheat leaves showed that the abundance ...Hybrid necrosis is the gradual premature death of leaves or plants in certain F1 hybrids of wheat (Triticum aestivum L.). Comparison of protein expression in necrotic and normal wheat leaves showed that the abundance of 33 proteins was changed significantly, and 24 of these proteins were identified. These proteins were involved in plant growth and development, antioxidation, photosynthesis and carbon assimilation, amino acid and protein biosynthesis, cytological signal transduction, DNA and RNA modification, protein transport, folding and assembly according to their functions. The down-regulation of uroporphyrinogen decarboxylase and the up-regulation of lipoxygenases in necrotic leaves may be related to the oxidative stress in the necrotic cells. The heat shock proteins may play the cytoprotective role. The differential expression of photosynthesis and carbon assimilation related proteins indicated chlorophyll biosynthesis and chloroplast development were inhibited and might finally cause the gradual chlorosis and cell death in necrotic leaves. The results of this study give a comprehensive picture of the post-transcriptional response to necrosis in hybrid wheat leaves and serve as a platform for further characterization of gene function and regulation in wheat hybrid necrosis.展开更多
Synthetic varieties(SVs)are populations generated by randomly mating their parents.They are a good alternative for low-input farmers who grow onions,maize,and other allogamous crops since the seed produced by a SV doe...Synthetic varieties(SVs)are populations generated by randomly mating their parents.They are a good alternative for low-input farmers who grow onions,maize,and other allogamous crops since the seed produced by a SV does not change from one generation to the next.Although SV progenitors are commonly pure lines,in this case a synthetic(Syn_(TC))whose parents are t three-way line crosses,a very common type of maize hybrid grown in Mexico,is studied.The aim was to develop a general and exact equation for the inbreeding coefficient of a Syn_(TC)eF_(m)^(f)Syn_(TC)T because of its relationship with the mean of economically important traits.This objective arose due to the need for a more advanced study in terms of determining whether F_(m)^(f)Syn_(TC)can be applied specifically and accurately for any number of parents(t),plants per parent(m)and inbreeding coefficient(IC)of the initial lines(F_(L)).A formula for the IC of the Syn_(TC)was derived that,given any values of F_(L)(0≤F_(L)≤1)and t,is specific for any value of m,not just for“large”numbers associated with the context in which the Hardy-Weinberg law is stated.It was found that F_(m)^(f)Syn_(TC)is very sensitive to changes in m when m is not greater than eight,after which it tends to stabilize very quickly.In summary,unlike previously derived formulas,F_(m)^(f)Syn_(TC)is exact for any values of t,m and F_(L).展开更多
Berseem clover (Trifolium alexandrinum L.) is the main winter forage legume in Egypt. Despite that the yield and protein content of berseem clover are high, it is characterized by low dry matter content especially in ...Berseem clover (Trifolium alexandrinum L.) is the main winter forage legume in Egypt. Despite that the yield and protein content of berseem clover are high, it is characterized by low dry matter content especially in the 1st cut. Intercropping berseem clover with forage grasses, especially annual ryegrass (Lolium multiflorum Lam.) is a recommended technique to produce higher forage yield with better balanced nutritional quality. However, little is known about the performance of these proposed mixtures under the arising organic farming system in Egypt. Organic farming and the application of organic fertilizers (compost and poultry manure) are receiving increased attention in the last few years. Thus, the current study was carried out on the winter season of two successive years (2012 and 2013) in the experimental station of SEKEM organic farm, Egypt. Main aim was to investigate the variation in 1st cut forage yield and nutritive value of berseem clover and annual ryegrass, grown in pure stands and with three mixing rates, under three organic fertilization regimes (compost, poultry litter, and no fertilization). Nutritive value was judged through investigating the crude protein (CP), total carbohydrates (TC), and fiber fractions (NDF, ADF, and ADL). Results revealed significant two-way interaction between the forage treatments and the fertilization regimes for all the studied parameters. In general, mixing berseem clover with annual ryegrass, fertilized by compost or poultry litter resulted in significantly higher forage yield, dry matter content, and balanced CP, TC, and fiber fractions, compared to the pure stands.展开更多
Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term ...Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term engine emissions and performance. This research uses oils produced in Colorado as a full diesel fuel substitute in a modified single cylinder engine. This engine testing was conducted in the laboratory. The test engine was a Yanmar TF140E, which is naturally aspirated and uses low pressure (~140 bar) mechanical direct injection. The engine fuel system was modified to accommodate a 2-tank custom SVO kit. The SVO was heated to 75 °C. Fuel economy and emissions measurements were performed for petroleum diesel, four different vegetable oils (sunflower, canola, camelina, and soybean) and their biodiesel derivatives. Fuel mass flow, oxides of nitrogen (NOX), total hydrocarbons (THC), carbon monoxide (CO), and particulate matter were measured. No engine degradation was experienced through approximately 50 hrs of testing on SVO and 50 hrs of testing on biodiesel. Overall engine emissions for SVO and biodiesel, with the exception of THC for biodiesel, were higher than petroleum diesel. More favorable biofuel emissions comparisons to diesel are expected with other engine designs based on data from various literature sources. Data comparing raw and refined SVO indicate that refined vegetable oil produces lower particulate matter (PM) emissions. General trends were observed showing that oils with higher levels of polyunsaturated fats (e.g. C18:1, C18:2, and C18:3) produce higher levels of NOX and THC’s.展开更多
The recently domesticated species, Cephalaria joppensis (CJ), is emerging as a new alternative forage crop in Israel. It has high biomass potential and nutritional values that are comparable to forage wheat. However, ...The recently domesticated species, Cephalaria joppensis (CJ), is emerging as a new alternative forage crop in Israel. It has high biomass potential and nutritional values that are comparable to forage wheat. However, CJ emerges slowly under cold conditions, which hinders its development as a major winter crop. Additional tolerance for abiotic stress would improve its performance as a forage crop. We examined the effects of several abiotic factors (i.e., cold, salinity, drought and pH) on CJ germination under controlled conditions. The effect of temperature was studied by incubating seeds at different temperatures between 7°C and 35°C. The effects of salinity, osmotic potential and pH were tested by incubating seeds at different NaCl, PEG and pH levels, respectively. Temperature, salinity and osmotic potential significantly affected germination;whereas pH did not. Temperature did not affect the final proportion of germinated seeds, but did affect other germination-rate variables, indicating that germination rate might be the limiting factor under field conditions. Salinity also affected germination-rate variables, but not the proportion of seeds that germinated. Notably, CJ was found to be relatively resistant to high salt concentrations, with a 273 mM NaCl threshold for germination, indicating its potential as a relatively salt-tolerant forage crop. Both the proportion of germinated seeds and the germination rate were highly sensitive to the osmotic-potential treatments, indicating that drought resistance will remain the biggest challenge for CJ. This study provides baseline data for a rapid and efficient system for further screening for abiotic-stress tolerance among wild and cultivated lines of CJ.展开更多
Large deposits of impure kaolins exist in Jordan and many parts of the world;geoplymers can reduce environmental impacts and have multi-application in many fields, such as water purification, waste treatment, fire pro...Large deposits of impure kaolins exist in Jordan and many parts of the world;geoplymers can reduce environmental impacts and have multi-application in many fields, such as water purification, waste treatment, fire proof construction, etc. The aim of this research is to investigate the use of alkali activated zeolitic tuff and low purity metakaolin as precursors for the production of functional geoplymers exhibiting proper mechanical properties and high potential for water storage and decontamination of polluted solutions. The results confirmed that this type of geopolymers showed superior mechanical characteristics and higher adsorption capacity towards heavy metals such as Cu(II) ions, which was similar to natural zeolite. X-ray diffraction analysis showed that phillipsite, a major zeolite mineral, disappeared upon geopolymerization, while scanning electron microscopy analysis showed that geopolymers exhibit a porous matrix of nano-particles. The geopolymers have also displayed high compressive strength and tensile bending strength of about 7.8 MPa and 45 MPa respectively, compared to reference geopolymers. This functional-geopolymers indicate that they are efficient, cost effective and have a potential for number of applications including construction, water storage and wastewater treatment.展开更多
基金supported by the National Nature Science Foundation of China,the National Key Research and Development Program of China(302001109,2016YFD0300508,2017YFD0301602,2018YFD0301105)the Fujian and Taiwan Cultivation Resources Development and Green Cultivation Coordination Innovation Center,China(Fujian 2011 Project,2015-75)the Natural Science Foundation of Fujian Province,China(2022J01142)。
文摘Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019.The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status.Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvesting, the timely application of nitrogen fertilizer is fundamental,coupled with moderate field drying for root-vigor preservation and tiller promotion before and after the mechanical harvesting of the main crop.
文摘The study being the first of its kind established an efficient protocol for micropropagation of Cryptolepis sanguinolenta, an important endangered medicinal plant species, used in the treatment of Malaria. For shoot induction, semi hard wood nodal segments were maintained on MS (Murashige and Skoog) nutrient medium supplemented with MS vitamins, 30 g/L sucrose, 3% gelrite and various auxin and cytokinin combinations. Treatments involved 6-benzyladenine (BA) at 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0 mg/L in combination with 0.1 mg/L Indole 3-butyric acid (IBA) or Naphthaleneacetic acid (NAA). Control consisted of hormone free MS medium. BA and IBA combinations were found to be more efficient in shoot regeneration than the BA and NAA combinations. Cultures maintained on MS medium supplemented with 3 mg/L BA, in combination with 0.1 mg/L IBA recorded the highest shoot induction (100%), mean shoot length (1.28 cm) and mean number of nodes per explant (2.5). This, however, did not differ significantly from cultures maintained on 2 or 2.5 mg/L BA and 0.1 mg/L IBA supplemented MS medium. Regenerated shoots were transferred onto different media for root induction. Treatments consisted of full strength MS medium augmented with either 0.5 or 0.1 mg/L IBA, hormone free half strength MS medium and half strength MS medium augmented with 0.01 mg/L IBA. After six weeks of culture, no rooting was recorded in all treatments with the exception of half strength MS medium supplemented with 0.01 mg/L IBA, which recorded 60% rooting. Regenerated plantlets were successfully weaned and established in the greenhouse.
基金financially supported by the National Natural Science Foundation of China(32161143033 and 32001574)the Agricultural Science and Technology Innovation Program of CAAS(2060203-2).
文摘Understanding the composition and contents of carotenoids in various soybean seed accessions is important for their nutritional assessment.This study investigated the variability in the concentrations of carotenoids and chlorophylls and revealed their associations with other nutritional quality traits in a genetically diverse set of Chinese soybean accessions comprised of cultivars and landraces.Genotype,planting year,accession type,seed cotyledon color,and ecoregion of origin significantly influenced the accumulation of carotenoids and chlorophylls.The mean total carotenoid content was in the range of 8.15–14.72μg g–1 across the ecoregions.The total carotenoid content was 1.2-fold higher in the landraces than in the cultivars.Soybeans with green cotyledons had higher contents of carotenoids and chlorophylls than those with yellow cotyledons.Remarkably,lutein was the most abundant carotenoid in all the germplasms,ranging from 1.35–37.44μg g–1.Carotenoids and chlorophylls showed significant correlations with other quality traits,which will help to set breeding strategies for enhancing soybean carotenoids without affecting the other components.Collectively,our results demonstrate that carotenoids are adequately accumulated in soybean seeds,however,they are strongly influenced by genetic factors,accession type,and germplasm origin.We identified novel germplasms with the highest total carotenoid contents across the various ecoregions of China that could serve as the genetic materials for soybean carotenoid breeding programs,and thereby as the raw materials for food sectors,pharmaceuticals,and the cosmetic industry.
文摘North Africa is one of the most regions impacted by water shortage.The implementation of controlled drainage(CD)in the northern Nile River delta of Egypt is one strategy to decrease irrigation,thus alleviating the negative impact of water shortage.This study investigated the impacts of CD at different levels on drainage outflow,water table level,nitrate loss,grain yield,and water use efficiency(WUE)of various wheat cultivars.Two levels of CD,i.e.,0.4 m below the soil surface(CD-0.4)and 0.8 m below the soil surface(CD-0.8),were compared with subsurface free drainage(SFD)at 1.2 m below the soil surface(SFD-1.2).Under each drainage treatment,four wheat cultivars were grown for two growing seasons(November 2018–April 2019 and November 2019–April 2020).Compared with SFD-1.2,CD-0.4 and CD-0.8 decreased irrigation water by 42.0%and 19.9%,drainage outflow by 40.3%and 27.3%,and nitrate loss by 35.3%and 20.8%,respectively.Under CD treatments,plants absorbed a significant portion of their evapotranspiration from shallow groundwater(22.0%and 8.0%for CD-0.4 and CD-0.8,respectively).All wheat cultivars positively responded to CD treatments,and the highest grain yield and straw yield were obtained under CD-0.4 treatment.Using the initial soil salinity as a reference,the soil salinity under CD-0.4 treatment increased two-fold by the end of the second growing season without negative impacts on wheat yield.Modifying the drainage system by raising the outlet elevation and considering shallow groundwater contribution to crop evapotranspiration promoted water-saving and WUE.Different responses could be obtained based on the different plant tolerance to salinity and water stress,crop characteristics,and growth stage.Site-specific soil salinity management practices will be required to avoid soil salinization due to the adoption of long-term shallow groundwater in Egypt and other similar agroecosystems.
文摘Sweetpotato is an important crop for food security in many developing countries which is cultivated using vine cuttings. Studies have revealed that there are at least fifteen well characterized viruses known to infect sweetpotato of which 10 are economically important that contribute to yield reduction. Planting materials use by farmers are often infected by one or more of these viruses. The aim of this study was to evaluate three different sources of planting materials of different health status for their field performance and virus presence. The sources of planting materials were in vitro generated platelets, symptomless Field materials and Farmer’s materials. Four sweetpotato varieties Apomuden, Bohye, Ligri and Dadanyuie were selected from each source of planting material. The trial was laid in a split plot design with the sources of planting material allocated to main plots and the varieties to sub-plots. The plantlets of the four varieties were planted at Botanga Irrigation Scheme in Northern region of Ghana. Viral symptom scores were taken twice, score 1 being the average from 4 - 7 weeks after planting (WAP) and score 2 being the average from 8 - 11 WAP. Nitrocellulose Membranes Enzyme Linked Immunosorbent Assay (NCM-ELISA) kits were employed for the detection of sweetpotato viruses on the field. The source of planting materials significantly influenced (P In vitro generated material showed the least symptoms of virus followed by Field materials. Apomuden and Bohye varieties recorded the highest virus score in the first and second virus symptom observational score respectively. NCM-ELISA revealed that the viruses SPFMV, SPMMV, SPMSV, SPCFV, SPCSV, and CMV were significantly present among the different sources of planting materials. In vitro, Field and Farmer materials recorded NCM-ELISA score of 0.225, 1.075 and 1.500 respectively. Apomuden variety recorded the highest virus score in the assay. Vine and root yield was higher among the in vitro generated material. Farmers should use laboratory cleaned material however, in the absence of such material they should select field material showing no symptom of virus.
基金supported by Ministry of Science and Technology of China(2016YFD0100201,2016YFD0100504 and 2017YFD0101400)National Science and Technology Major Project of China(2016ZX08004-003)+2 种基金National Natural Science Foundation of China(No.31671716)Beijing Science and Technology Plan Project(Z16110000916005)CAAS(Chinese Academy of Agricultural Sciences)Agricultural Science and Technology Innovation Program。
文摘The stability of soybean(Glycine max L.Merrill)oil is determined mainly by its fatty acid(FA)composition.We evaluated the FA composition of 1025 Chinese soybean accessions collected from diverse ecoregions and grown in multiple locations and years.We observed highly significant differences(P<0.001)between accessions in palmitic acid(PA),stearic acid(SA),oleic acid(OA),linoleic acid(LA),and linolenic acid(LNA)contents.Growth year affected(P<0.001)the abundance of all FAs except PA.The mean PA,SA,OA,LA,and LNA contents were 12.2%,3.8%,21.5%,54.2%,and 8.3%,respectively.The geographical origin of the accession influenced seed FA composition,indicating that accessions originating in each ecoregion tend to have distinct FA composition.We observed significant positive correlations among the three locations and between the two years,suggesting the high heritability and stability of individual accessions across contrasting environments.We also observed a relatively high negative correlation between the contents of OA and both LA and LNA(r=-0.90 and-0.59,respectively,each significant at P<0.001),providing a potential entry point for developing strains producing oil with higher OA and lower LA and LNA levels.These would be appropriate for specialized use in the food industry.Our results will be useful in breeding soybean with improved quality to meet human nutritional and industrial needs.
文摘The foliar application of micro- and macronutrients is often practiced by farmers to improve yield and seed physiological potential. For calcium and molybdenum, positive results have been observed, even in soils with high nutrient content. The purpose of this study was to assess the effects of foliar applications of calcium and molybdenum on yield and seed physiological potential in common bean plants. A randomized block design was implemented, with the treatments fixed in a factorial scheme: two molybdenum rates (with or without) and four calcium rates, with four replications. The calcium rates applied on the leaves were 0, 150, 300 and 600 g·ha-1 for the first year of the investigation (2005) and 0, 300, 600 and 900 g·ha-1 for the second year (2006). In both years, the molybdenum rates applied on the leaves were 0 g·ha-1 (without) and 75 g·ha-1 (with). The results showed that the foliar calcium application, with or without molybdenum, did not improve yield. Foliar application of calcium alone improved seed physiological potential in common bean plants when applied at the full bloom stage.
文摘Tissue culture (TC) banana plantlets at the in vitro stage are delicate and devoid of microbes and nutrients that are essential for establishment and subsequent growth. Some microbes are known for function best under certain soil threshold levels of macro and micronutrients and have been associated with growth and performance of TC banana. A green house and field study was conducted to evaluate the effect of combining two commercial biological products [Rhizatech and ECO-T (mycorrhiza and Trichoderma based products, respectively)] with various sources of nitrogen and phosphorous including Mavuno, Minjingu phosphate rock, Calcium Ammonium Nitrate (CAN), manure and diammonium phosphate (DAP) on growth and performance of TC banana in Vertisol and Rhodic Ferralsol soil conditions. Tissue culture plants were initially inoculated with Rhizatech and ECO-T at the acclimatization stage and subsequently at the beginning of the potting stage and field establishment. Addition of nutrient sources was also done at the same stages of plant growth by mixing with the soil substrates prior to planting. The performance of plants was significantly (at p ≤ 0.05) affected by the combinations of nutrient sources depending on the soil type and stage of plant development. The growth of plants in the Vertisol increased with Trichoderma combined with either organic manure, DAP or combined with a macro and micro nutrient source (Mavuno) as compared to the sole application of Trichoderma. Performance of plants treated with combination of mycorrhiza and either Mavuno and minjigu rock phosphate was consistently higher in the Rhodic Ferralsol than either mycorrhiza alone or fertilizer alone. This indicates that TC plants could highly benefit from combined application of microbiological products and inorganic and organic fertilizers. However, a prior knowledge of the product’s microbial formulation and prevailing soil conditions is essential for optimizing the potential benefits of integrating microbe-based product with inorganic and organic fertilizers.
基金supported by the National Natural Science Foundation of China (30440047)the Program for Germplasm Innovation and Utilization from the Ministry of Agriculture of China (NB2010-2130135)
文摘Hybrid necrosis is the gradual premature death of leaves or plants in certain F1 hybrids of wheat (Triticum aestivum L.). Comparison of protein expression in necrotic and normal wheat leaves showed that the abundance of 33 proteins was changed significantly, and 24 of these proteins were identified. These proteins were involved in plant growth and development, antioxidation, photosynthesis and carbon assimilation, amino acid and protein biosynthesis, cytological signal transduction, DNA and RNA modification, protein transport, folding and assembly according to their functions. The down-regulation of uroporphyrinogen decarboxylase and the up-regulation of lipoxygenases in necrotic leaves may be related to the oxidative stress in the necrotic cells. The heat shock proteins may play the cytoprotective role. The differential expression of photosynthesis and carbon assimilation related proteins indicated chlorophyll biosynthesis and chloroplast development were inhibited and might finally cause the gradual chlorosis and cell death in necrotic leaves. The results of this study give a comprehensive picture of the post-transcriptional response to necrosis in hybrid wheat leaves and serve as a platform for further characterization of gene function and regulation in wheat hybrid necrosis.
文摘Synthetic varieties(SVs)are populations generated by randomly mating their parents.They are a good alternative for low-input farmers who grow onions,maize,and other allogamous crops since the seed produced by a SV does not change from one generation to the next.Although SV progenitors are commonly pure lines,in this case a synthetic(Syn_(TC))whose parents are t three-way line crosses,a very common type of maize hybrid grown in Mexico,is studied.The aim was to develop a general and exact equation for the inbreeding coefficient of a Syn_(TC)eF_(m)^(f)Syn_(TC)T because of its relationship with the mean of economically important traits.This objective arose due to the need for a more advanced study in terms of determining whether F_(m)^(f)Syn_(TC)can be applied specifically and accurately for any number of parents(t),plants per parent(m)and inbreeding coefficient(IC)of the initial lines(F_(L)).A formula for the IC of the Syn_(TC)was derived that,given any values of F_(L)(0≤F_(L)≤1)and t,is specific for any value of m,not just for“large”numbers associated with the context in which the Hardy-Weinberg law is stated.It was found that F_(m)^(f)Syn_(TC)is very sensitive to changes in m when m is not greater than eight,after which it tends to stabilize very quickly.In summary,unlike previously derived formulas,F_(m)^(f)Syn_(TC)is exact for any values of t,m and F_(L).
文摘Berseem clover (Trifolium alexandrinum L.) is the main winter forage legume in Egypt. Despite that the yield and protein content of berseem clover are high, it is characterized by low dry matter content especially in the 1st cut. Intercropping berseem clover with forage grasses, especially annual ryegrass (Lolium multiflorum Lam.) is a recommended technique to produce higher forage yield with better balanced nutritional quality. However, little is known about the performance of these proposed mixtures under the arising organic farming system in Egypt. Organic farming and the application of organic fertilizers (compost and poultry manure) are receiving increased attention in the last few years. Thus, the current study was carried out on the winter season of two successive years (2012 and 2013) in the experimental station of SEKEM organic farm, Egypt. Main aim was to investigate the variation in 1st cut forage yield and nutritive value of berseem clover and annual ryegrass, grown in pure stands and with three mixing rates, under three organic fertilization regimes (compost, poultry litter, and no fertilization). Nutritive value was judged through investigating the crude protein (CP), total carbohydrates (TC), and fiber fractions (NDF, ADF, and ADL). Results revealed significant two-way interaction between the forage treatments and the fertilization regimes for all the studied parameters. In general, mixing berseem clover with annual ryegrass, fertilized by compost or poultry litter resulted in significantly higher forage yield, dry matter content, and balanced CP, TC, and fiber fractions, compared to the pure stands.
文摘Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term engine emissions and performance. This research uses oils produced in Colorado as a full diesel fuel substitute in a modified single cylinder engine. This engine testing was conducted in the laboratory. The test engine was a Yanmar TF140E, which is naturally aspirated and uses low pressure (~140 bar) mechanical direct injection. The engine fuel system was modified to accommodate a 2-tank custom SVO kit. The SVO was heated to 75 °C. Fuel economy and emissions measurements were performed for petroleum diesel, four different vegetable oils (sunflower, canola, camelina, and soybean) and their biodiesel derivatives. Fuel mass flow, oxides of nitrogen (NOX), total hydrocarbons (THC), carbon monoxide (CO), and particulate matter were measured. No engine degradation was experienced through approximately 50 hrs of testing on SVO and 50 hrs of testing on biodiesel. Overall engine emissions for SVO and biodiesel, with the exception of THC for biodiesel, were higher than petroleum diesel. More favorable biofuel emissions comparisons to diesel are expected with other engine designs based on data from various literature sources. Data comparing raw and refined SVO indicate that refined vegetable oil produces lower particulate matter (PM) emissions. General trends were observed showing that oils with higher levels of polyunsaturated fats (e.g. C18:1, C18:2, and C18:3) produce higher levels of NOX and THC’s.
文摘The recently domesticated species, Cephalaria joppensis (CJ), is emerging as a new alternative forage crop in Israel. It has high biomass potential and nutritional values that are comparable to forage wheat. However, CJ emerges slowly under cold conditions, which hinders its development as a major winter crop. Additional tolerance for abiotic stress would improve its performance as a forage crop. We examined the effects of several abiotic factors (i.e., cold, salinity, drought and pH) on CJ germination under controlled conditions. The effect of temperature was studied by incubating seeds at different temperatures between 7°C and 35°C. The effects of salinity, osmotic potential and pH were tested by incubating seeds at different NaCl, PEG and pH levels, respectively. Temperature, salinity and osmotic potential significantly affected germination;whereas pH did not. Temperature did not affect the final proportion of germinated seeds, but did affect other germination-rate variables, indicating that germination rate might be the limiting factor under field conditions. Salinity also affected germination-rate variables, but not the proportion of seeds that germinated. Notably, CJ was found to be relatively resistant to high salt concentrations, with a 273 mM NaCl threshold for germination, indicating its potential as a relatively salt-tolerant forage crop. Both the proportion of germinated seeds and the germination rate were highly sensitive to the osmotic-potential treatments, indicating that drought resistance will remain the biggest challenge for CJ. This study provides baseline data for a rapid and efficient system for further screening for abiotic-stress tolerance among wild and cultivated lines of CJ.
文摘Large deposits of impure kaolins exist in Jordan and many parts of the world;geoplymers can reduce environmental impacts and have multi-application in many fields, such as water purification, waste treatment, fire proof construction, etc. The aim of this research is to investigate the use of alkali activated zeolitic tuff and low purity metakaolin as precursors for the production of functional geoplymers exhibiting proper mechanical properties and high potential for water storage and decontamination of polluted solutions. The results confirmed that this type of geopolymers showed superior mechanical characteristics and higher adsorption capacity towards heavy metals such as Cu(II) ions, which was similar to natural zeolite. X-ray diffraction analysis showed that phillipsite, a major zeolite mineral, disappeared upon geopolymerization, while scanning electron microscopy analysis showed that geopolymers exhibit a porous matrix of nano-particles. The geopolymers have also displayed high compressive strength and tensile bending strength of about 7.8 MPa and 45 MPa respectively, compared to reference geopolymers. This functional-geopolymers indicate that they are efficient, cost effective and have a potential for number of applications including construction, water storage and wastewater treatment.
