In this note we study subplanes of order q of the projective plane Π=PG( 2, q 3 ) and the ruled varieties V 2 5 of Σ=PG( 6,q ) using the spatial representation of Π in Σ, by fixing a hyperplane Σ ′ with a regula...In this note we study subplanes of order q of the projective plane Π=PG( 2, q 3 ) and the ruled varieties V 2 5 of Σ=PG( 6,q ) using the spatial representation of Π in Σ, by fixing a hyperplane Σ ′ with a regular spread of planes. First are shown some configurations of the affine q-subplanes. Then to prove that a variety V 2 5 of Σ represents a non-affine subplane of order q of Π, after having shown basic incidence properties of it, such a variety V 2 5 is constructed by choosing appropriately the two directrix curves in two complementary subspaces of Σ. The result can be translated into further incidence properties of the affine points of V 2 5 . Then a maximal bundle of varieties V 2 5 having in common one directrix cubic curve is constructed.展开更多
Cotton (Gossypium hirsutum L.) is an importantfiber cash crop,but its root traits related to phosphorus (P) acquisition,including mycorrhizal root traits,are poorly understood.Eight cotton varieties bred in northweste...Cotton (Gossypium hirsutum L.) is an importantfiber cash crop,but its root traits related to phosphorus (P) acquisition,including mycorrhizal root traits,are poorly understood.Eight cotton varieties bred in northwestern China that were released between 1950 and 2013 were grown in pots with or without one arbuscular mycorrhizal fungal (AMF) species(Funneliformis mosseae) at three P supply levels (0,50 and 300 mg P as KH_(2)PO_(4)kg^(-1)).Eleven root traits were measured and calculated after 7 wk of growth.The more recent accessions had smaller root diameters,acquired less P and produced less biomass,indicating an (inadvertent) varietal selection for thinner roots that provided less cortical space for AMF,which then increased the need for a high P fertilizer level.At the two lower P levels,the mycorrhizal plants acquired more P and produced more biomass than non-mycorrhizal plants (3.2 vs.0.9 mg P per plant;1.8 vs.0.9 g biomass per plant at P_(0);14.5 vs.1.7 mg P per plant;and 4.7 vs.1.6 g biomass per plant at P_(50)).At the highest P level,the mycorrhizal plants acquired more P than non-mycorrhizal plants (18.8 vs.13.4 mg per P plant),but there was no difference in biomass (6.2 vs.6.3 g per plant).At the intermediate P level,root diameter was significantly positively correlated with shoot biomass,P concentration and the P content of mycorrhizal plants.The results of our study support the importance of the outsourcing model of P acquisition in the root economics space framework.Inadvertent varietal selection in the last decades,resulting in thinner roots and a lower benefit from AMF,has led to a lower productivity of cotton varieties at moderate P supply (i.e.,when mycorrhizal,the average biomass of older varieties 5.0 g per plant vs.biomass of newer varieties 4.4 g per plant),indicating the need to rethink cotton breeding efforts in order to achieve high yields without very high P input.One feasible way to solve the problem of inadvertent varietal selection for cotton is to be aware of the trade-offs between the root do-it-yourself strategy and the outsourcing towards AMF strategy,and to consider both morphological and mycorrhizal root traits when breeding cotton varieties.展开更多
The hydrophobic cuticle encasing the fruit skin surface plays critical roles during fruit development and post-harvest.Skin failure often results in the fruit surface cracking and forming a wound-periderm tissue made ...The hydrophobic cuticle encasing the fruit skin surface plays critical roles during fruit development and post-harvest.Skin failure often results in the fruit surface cracking and forming a wound-periderm tissue made of suberin and lignin.The factors that make the fruit skin susceptible to cracking have yet to be fully understood.Herein,we investigated two varieties of chili peppers(Capsicum annuum L.),Numex Garnet,whose fruit has intact skin,and Vezena Slatka,whose fruit has cracked skin.Microscopical observations,gas chromatography-mass spectrometry,biochemical and gene expression assays revealed that Vezena Slatka fruit form a thicker cuticle with greater levels of cutin monomers and hydroxycinnamic acids,and highly express key cutin-related genes.The skin of these fruit also had a lower epidermal cell density due to cells with very large perimeters,and highly express genes involved in epidermal cell differentiation.We demonstrate that skin cracking in the Vezena Slatka fruit is accompanied by a spatial accumulation of lignin-like polyphenolic compounds,without the formation of a typical wound-periderm tissues made of suberized cells.Lastly,we establish that skin cracking in chili-type pepper significantly affects fruit quality during post-harvest storage in a temperature-dependent manner.In conclusion,our data highlight cuticle thickness and epidermal cell density as two critical factors determining fruit skin susceptibility to cracking in chili-type pepper fruit.展开更多
Coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furth...Coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furthermore, the shade in the production systems has decreased with the consequent increase in soil erosion, in addition to the increase in agrochemicals. Currently, the planting of new varieties with resistance to the fungus is increasing. Furthermore, it has been shown that various biofertilized perennial crops in nursery favor their growth. In this study, the effect of applying two beneficial microorganisms, Rhizophagus intraradices and/or Azospirillum brasilense, to the planting of four varieties of Coffea arabica L. was evaluated. The coffee varieties marseillase, geisha, sarchimor and costa rica 95 were established in bags with the following treatments: 1) control, 2) R. intraradices, 3) A. brasilense, 4) R. intraradices + A. brasilense. Morphological and physiological yield components were recorded 168 days after transplanting. Data was analyzed statistically and differences between treatments were compared according to Tukey (p ≤ 0.05). The results indicate that individual or combined biofertilization of microorganisms favors dry matter allocation compared to the control and the same is differentially assigned to the stem and root. The Specific Leaf Area (SLA) also showed differential response between applications of the microorganisms, in two varieties it increased when they were applied alone and in the others when they were applied together.展开更多
[Objectives]To study the introduction performance of pomegranate(Punica granatum)varieties in Shanghai area.[Methods]In this experiment,five pomegranate varieties were introduced,namely‘American 002’pomegranate,‘Hu...[Objectives]To study the introduction performance of pomegranate(Punica granatum)varieties in Shanghai area.[Methods]In this experiment,five pomegranate varieties were introduced,namely‘American 002’pomegranate,‘Huohulu’pomegranate,‘Wanli No.1’pomegranate,‘Yicheng Hongpitian’pomegranate,and‘American Qingpisuan’pomegranate.Then,using these five varieties,various biological traits such as phenology and fruit quality of pomegranate,as well as stress resistance such as heat resistance and cold resistance were studied.[Results]Five varieties of pomegranates began to mature in succession in early September;the smallest single fruit weight was 90 g,and the largest was 110 g;the plants grew fast,the plants were strong,the flowers were single petal,and plants bore fruits which were ornamental and edible.In addition,the pomegranates of these five varieties had good water tolerance and heat resistance,and good cold resistance.[Conclusions]This study is intended to provide a certain reference for the introduction of pomegranate varieties,and also provide a practical basis for the large-scale planting of pomegranate.展开更多
It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge...It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge (ITK) of the diversity of cassava varieties in terms of: their morphology, growth characteristics, uses (of tubers and leaves) and desirable characteristics. The objective is to see to what extent the objectives of the plant breeders are consistent with what farmers’ value. We performed 405 structured and semi-structured interviews with informants who were selected based on “purposive household sampling”. We found a considerable turn-over in cassava varieties, just over a third (45) have been in cultivation for at least 40 years, however, since the end of the civil war an additional 25 varieties are cultivated, while others varieties seem to have disappeared. One major issue with estimating turnover of varieties is whether the same variety might have several local names, and conversely the same name may be applied to different cultivars. Farmers overwhelmingly use ITK to select and preserve cassava germplasm for future use. Farmers have a clear preference for: sweet taste, high yield, early maturity and easy cooking and preferentially adopt cultivars that have those qualities. Cassava is primarily a human food eaten boiled or fried, some are processed into fufu and gari, and uses as livestock feed and medicine are reported but at low levels. The information produced during this study could help plant breeders choose selection criteria that will ensure their efforts are adopted and sustainable, the importance of preserving the genetic resources of local cultivars is also highlighted.展开更多
The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and ph...The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and physiological quality. Taking into account that currently there is no categorization in terms of susceptibility and tolerance on this pathogen, the present work is presented with the main objective of “Evaluate the influence of Pathogenicity of C. truncatum on the physiological quality (germination, vigor, viability) and biochemical components in different varieties of soybean seeds (Glycine max)” most planted in the region. The work was carried out in the Agrotec laboratory, located in the Municipality of San Alberto (Alto Paraná), using a completely randomized experimental design, with AxB factorial arrangement, where A indicates ten most planted soybean varieties in the region and B with or without artificial inoculation of Colletotrichum truncatum, with twenty treatments and four repetitions. The variables evaluated were: germination, vigor, viability and chemical composition. The data were subjected to analysis of variance and the Tukey test at 5% error. The results showed a significant statistical difference, accepting the alternative hypothesis proposed “The pathogenicity of Colletotrichum truncatum influences the physiological quality (germination, vigor, viability) and biochemical components (saturated and unsaturated fatty acids) in different varieties of soybean seeds (Glycine max)”.展开更多
Improved rice varieties(IRVs)play a significant role in establishing food security and improving livelihood in the Global South since its introduction in the 1960s.However,the adoption of new IRVs has remained relativ...Improved rice varieties(IRVs)play a significant role in establishing food security and improving livelihood in the Global South since its introduction in the 1960s.However,the adoption of new IRVs has remained relatively low.This low adoption poses a challenge to rice-producing and consuming countries as they are increasingly threatened by production shortages,malnutrition,and poor rice quality.Many empirical studies have attempted to identify the determinants influencing the adoption of IRVs by distinguishing the characteristics between adopters and non-adopters.This review showed a consensus on the important determinants influencing the adoption of IRVs in the Global South.Findings synthesized from 99 studies suggested that variables(farm size,education,information access and farm location)examined extensively are not necessarily the most important determinants of adoption when undertaking a weighted analysis.Terrain,source of seed and technology-related attributes(perceived yield,maturity,ease of use,marketability and technical efficiency)are more important determinants of adoption,with determinants changing according to adoption type(probability or intensity of adoption),variety type and region.The recommendations for future adoption studies include:incorporating more technology-specific variables,increasing research for overlooked regions and variety types,shifting away from predominant static analysis by capturing the dynamics of the adoption process,and considering the potential biases in analyses.This review will facilitate the development of targeted interventions and policies that promote IRV adoption in the Global South.展开更多
[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong...[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong Tianjiao,Hongfuji,Yongfeng 1,Beinong Futian,Beinong Shijia,and Beinong Jinxiu,and Jingxin 2 was used as the control check(CK).The growth period,morphological traits,yield traits and fruit quality of the tested varieties were investigated.[Results]Beinong Tianjiao 2 had an earlier maturation stage,a fruit development period of 38 d and a total growth period of 118 d.It showed stable growth,with a single fruit weight of 7.56 kg,a fruit setting rate of 0.99 per plant,and a yield of 83076.9 kg/hm~2,which ranked,respectively,second,first,and second among all tested varieties,and were significantly superior to the CK.Furthermore,this variety had thin and tough peel,a bright red flesh color,high central sugar content,loose and crisp flesh,and a good taste.[Conclusions]It is preliminarily believed that it is suitable for early spring watermelon production in Beijing area.展开更多
[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijin...[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing.展开更多
[Objectives]To study the adaptability of introduced pear.[Methods]Five pear varieties,"Aidang"pear,"Taiwan Zaomi"pear,"Cuiguan"pear,"Tianjin Yali"pear and"Zaosheng Xinshui&...[Objectives]To study the adaptability of introduced pear.[Methods]Five pear varieties,"Aidang"pear,"Taiwan Zaomi"pear,"Cuiguan"pear,"Tianjin Yali"pear and"Zaosheng Xinshui"pear,were introduced.Then,using these five varieties,the phenology of pear trees,various characters of fruit,stress resistance(heat tolerance and cold tolerance)of varieties were studied.[Results]The plants of 5 varieties of pear trees grew fast and were robust;in late March,it went into the flowering period;"Aidang"pear fruit had a certain number of stone cells;"Taiwan Zaomi"pear had the highest sweetness;"Cuiguan"pear had the largest fruit;these five varieties of pear trees had good water resistance,heat resistance and cold resistance.[Conclusions]This study can provide a reference for the introduction of pear trees,and can also provide a practical basis for the large-scale planting of pear trees.展开更多
[Objectives]To select zucchini varieties suitable for cultivation in Zibo City and test its high-yield cultivation techniques.[Methods]Six zucchini varieties were introduced,and their commercial quality and yield were...[Objectives]To select zucchini varieties suitable for cultivation in Zibo City and test its high-yield cultivation techniques.[Methods]Six zucchini varieties were introduced,and their commercial quality and yield were determined.[Results]The yield of Shengfeier,Xiuyu 170 and Xihulu 309 increased by 11.4%,6.9%and 4.6%,respectively compared with S68(control),and zucchini was straight,looked pleasing to the eye,and had strong disease resistance.[Conclusions]The zucchini varieties were selected and the high-quality,high-yield and high-efficiency cultivation techniques were integrated.展开更多
This experiment aims to increase sweet pepper production sustainably by using manures and a combination of manure and fertilizer. Manures are well known to improve soil health and maintain crop production for a relati...This experiment aims to increase sweet pepper production sustainably by using manures and a combination of manure and fertilizer. Manures are well known to improve soil health and maintain crop production for a relatively long period. This study was conducted under a tunnel house at the National Agricultural Research and Extension Institute at Mon Repos East Coast Demerara, Guyana. Plots were arranged according to strip plot design with two treatments (Aristotle and Sunsation), four rates (R1: 0 g/plant), (R2: 350 kg NPK/ha + 10 t vermicompost/ha), (R3: 10 t poultry manure/ha + 10 t vermicompost/ha and (R4: 350 kg NPK/ha + 10 t poultry manure/ha) and replicated thrice. These nutrients were applied in a split application at four weeks before planting, and four, eight, and twelve-week intervals after planting. The varieties did not differ from one another for the vegetative parameters tested. Plants treated with Rate 2 achieved significantly better growth parameters such as plant height, plant spread, and number of branches than the other rates. Sunsation obtained a significantly higher yield of 21.4 t/ha at the 5% level as compared to Aristotle (19.9 t/ha). The various rates recorded significant differences in yield. Rate 2 obtained a significantly higher yield of 32.8 t/ha followed by Rate 4 with 24.9 t/ha, then Rate 3 (17.0 t/ha). The lowest yield of 7.8 t/ha was attained by Rate 1. The interaction of varieties and rates showed statistically significant differences in yield. The interaction of Sunsation and Aristotle with Rate 2 achieved a superior yield of 34.8 t/ha and 30.7 t/ha respectively than other rates. Rate 4 also obtained significant interaction with Sunsation and Aristotle to achieve a yield of 25.7 t/ha and 24.1 t/ha respectively than Rate 3. Rate 3 interacted significantly with Sunsation and Aristotle and obtained a yield of 16.5 t/ha and 17.5 t/ha compared to Rate 1. Rate 1 achieved the least interaction for both varieties tested. Rates differed significantly for fruit shelf-life at room temperature. Fruits obtained from Rate 3 recorded a significantly longer fruit shelf-life of 14.7 days for 50% decay when stored at room temperature (30.3˚C) than other rates. The lowest fruit shelf-life of 7.7 days was obtained from Rate 1. This study indicated that the Sunsation variety is better to cultivate because of superior improvement in growth and yield attributes. The application of Rate 2 can considerably increase yield and when combined with Sunsation variety superior yield and yield attributes can be obtained.展开更多
Objective Using the stable isotope ratio method for the authenticity identification and variety identification of refined honey.Methods In this paper,a total of 17 samples of different varieties of refined honey were ...Objective Using the stable isotope ratio method for the authenticity identification and variety identification of refined honey.Methods In this paper,a total of 17 samples of different varieties of refined honey were used to obtain refined honey proteins by precipitation with sodium tungstate solution and sulphuric acid solution.The isotope mass spectrometer was used to simultaneously detect theδ^(13)C values of refined honey proteins and refined honey as well as theδ^(18)O andδ^(2)H values of refined honey,processed of the results obtained,analysed the authenticity of the samples and conduct a variety identification study.Results Tested of the resulting honey samples,the results showed that four batches of refined honey did not up to standard,two batches of C-4 vegetable syrup were detected as adulterated,and two batches of protein were not detected.Theδ^(18)O andδ^(2)H values of refined honey were also found to be effective in distinguishing the varietal origin of refined honey to a certain extent.Conclusions The stable isotope ratio method is useful in the authenticity identification of refined honey,and provides new ideas to further promote the authenticity of refined honey and variety identification research.展开更多
English varieties have grown up in different parts of the world. The traditional prototype paradigm of ELT,which assumed that a non-native learner learned English in order to communicate with a native speaker,no longe...English varieties have grown up in different parts of the world. The traditional prototype paradigm of ELT,which assumed that a non-native learner learned English in order to communicate with a native speaker,no longer represents the primary context of the use of English today. Therefore,in ELT,besides learning standard English,sensitivity to English varieties should be cultivated so as to promote communicative competence.展开更多
Learner's motivation is very important in learning process and learning result. It can be divided into different varieties. The positive factors which can influence learner's motivation can play a vital role i...Learner's motivation is very important in learning process and learning result. It can be divided into different varieties. The positive factors which can influence learner's motivation can play a vital role in College English teaching. In college English learning and teaching, teachers should adopt suitable teaching strategies and methods to realize these positive factors in order to im-prove college students English learning.展开更多
This paper focuses on the nativization of English in China,using Pidgin English as a case study to put Chinese English variants under the theoretical framework of eco-linguistics,and put the ecological environment suc...This paper focuses on the nativization of English in China,using Pidgin English as a case study to put Chinese English variants under the theoretical framework of eco-linguistics,and put the ecological environment such as species competition,coexistence and co-evolution,etc.The natural phenomenon is compared with the existence of language phenomenon in the development process of China English represented by Pidgin English.The study found that as the spark of the collision of the two mainstream languages of Chinese and English,the Chinese English varieties play a very important role in the exchange and enrichment of the two languages and cultures.Although academic circles have different attitudes and opinions on Chinese English variants,their existence and development conform to the law of the development of things and are also inevitable in historical development.Blindly ignoring their objective existence will definitely bring adverse effects on the ecological balance of the language.We should face up to the existence of Chinese English variants,comply with the law of language development,and allow it to develop naturally,and make efforts to protect the ecological balance of the world’s languages.展开更多
Understanding the morphological and physiological traits associated with improved filling efficiency in large-panicle rice varieties is critical to devise strategies for breeding programs and cultivation management pr...Understanding the morphological and physiological traits associated with improved filling efficiency in large-panicle rice varieties is critical to devise strategies for breeding programs and cultivation management practices.Information on such traits,however,remains limited.Two large-panicle varieties with high filled-grain percentage(HF) and two check large-panicle varieties with low filled-grain percentage(LF) were field-grown in 2012 and 2013.The number of spikelets per panicle of HF and LF both exceeded 300,and the filled-grain percentage(%) of HF was approximately 90,while that of LF was approximately 75 over the two years.The results showed that when the values were averaged across two years,HF yielded 12.91 ha^(-1),while LF yielded 11.01 ha^(-1).HF had a greater leaf area duration,biomass accumulation and transport of carbohydrates stored in the culm to the grains from heading to maturity compared with LF.HF exhibited a higher leaf photosynthetic rate,more green leaves on the culm,and higher root activity during filling phase,especially during the middle and late filling phases,in relative to LF.The length of HF for upper three leaves was significantly higher than that of LF,while the angle of upper three leaves on the main culm was less in both years.Meanwhile,specific leaf weight of HF was significantly higher when compared with LF.In addition,the grain filling characteristics of HF and LF were investigated in our study.Our results suggested that a higher leaf photosynthetic rate and root activity during filling phase,greater biomass accumulation and assimilate transport after heading,and longer,thicker and more erect upper three leaves were important morphological and physiological traits of HF,and these traits could be considered as selection criterion to develop large-panicle varieties with high filled-grain percentage.展开更多
Distinctness,uniformity and stability(DUS)Test Guidelines for new varieties of Viburnum L.were developed according to the principles and requirements of the International Union for the Protection of New Varieties of P...Distinctness,uniformity and stability(DUS)Test Guidelines for new varieties of Viburnum L.were developed according to the principles and requirements of the International Union for the Protection of New Varieties of Plants(UPOV)and China.The development processes,including selection and determination of testing characteristics,determination of expression states of characteristics,selection of example varieties,determination of the order of characteristics,and assessment of distinctness,uniformity and stability,are described in this paper.There were 54 testing characteristics:24 qualitative characteristics(QL),15 quantitative characteristics(QN),15 pseudoqualitative characteristics(PQ)and 34 example varieties in the DUS Test Guidelines.Among the 54 testing characteristics,20 were asterisked and 34 were non-asterisked.Seven were selected for variety groupings and 18 were adopted in the Technical Questionnaire.The development of these DUS Test Guidelines will be useful for the application and protection of new Viburnum varieties.The Guidelines will provide technical support for DUS testing of Viburnum and serve as a reference for the development of new varieties in other countries.展开更多
Cymbidium has been artificially domesticated for centuries in Asia,which produced numerous cultivated varieties.Flowers with stamenoid tepals or those with multiple tepals have been found in different species of Cymbi...Cymbidium has been artificially domesticated for centuries in Asia,which produced numerous cultivated varieties.Flowers with stamenoid tepals or those with multiple tepals have been found in different species of Cymbidium;however,the molecular basis controlling the formation of these phenotypes is still largely unknown.Previous work demonstrated that AGAMOUS/AG lineage MADS genes function in floral meristem determinacy as well as in reproductive organs development in both dicots and monocots,indicating a possible relationship with the origin of two flower varieties in Cymbidium.Here,we characterized and analyzed two AG lineage paralogues,CsAG1 and CsAG2,from Cymbidium sinense,both of which were highly expressed in the gynostemium column of a standard C.sinense.Interestingly,we detected ectopic expression of CsAG1 rather than CsAG2 in all floral organs of a stamenoid-tepal variety and significant down-regulation of CsAG1 in a variety with multiple tepals.Over-expression of CsAG1 in wild type Arabidopsis resulted in petal-to-stamen homeotic conversion,suggesting a conserved C-function of CsAG1 in the development of Cymbidium flower.Altogether,our results supported a hypothesis that disruption of a single AG-like factor would be associated with the formation of two domesticated varieties in C.sinense.展开更多
文摘In this note we study subplanes of order q of the projective plane Π=PG( 2, q 3 ) and the ruled varieties V 2 5 of Σ=PG( 6,q ) using the spatial representation of Π in Σ, by fixing a hyperplane Σ ′ with a regular spread of planes. First are shown some configurations of the affine q-subplanes. Then to prove that a variety V 2 5 of Σ represents a non-affine subplane of order q of Π, after having shown basic incidence properties of it, such a variety V 2 5 is constructed by choosing appropriately the two directrix curves in two complementary subspaces of Σ. The result can be translated into further incidence properties of the affine points of V 2 5 . Then a maximal bundle of varieties V 2 5 having in common one directrix cubic curve is constructed.
基金financially supported by the National Natural Science Foundation of China(32272807 and U1703232)supported via project from State Key Laboratory of North China Crop Improvement and Regulation(NCCIR2021ZZ-1)。
文摘Cotton (Gossypium hirsutum L.) is an importantfiber cash crop,but its root traits related to phosphorus (P) acquisition,including mycorrhizal root traits,are poorly understood.Eight cotton varieties bred in northwestern China that were released between 1950 and 2013 were grown in pots with or without one arbuscular mycorrhizal fungal (AMF) species(Funneliformis mosseae) at three P supply levels (0,50 and 300 mg P as KH_(2)PO_(4)kg^(-1)).Eleven root traits were measured and calculated after 7 wk of growth.The more recent accessions had smaller root diameters,acquired less P and produced less biomass,indicating an (inadvertent) varietal selection for thinner roots that provided less cortical space for AMF,which then increased the need for a high P fertilizer level.At the two lower P levels,the mycorrhizal plants acquired more P and produced more biomass than non-mycorrhizal plants (3.2 vs.0.9 mg P per plant;1.8 vs.0.9 g biomass per plant at P_(0);14.5 vs.1.7 mg P per plant;and 4.7 vs.1.6 g biomass per plant at P_(50)).At the highest P level,the mycorrhizal plants acquired more P than non-mycorrhizal plants (18.8 vs.13.4 mg per P plant),but there was no difference in biomass (6.2 vs.6.3 g per plant).At the intermediate P level,root diameter was significantly positively correlated with shoot biomass,P concentration and the P content of mycorrhizal plants.The results of our study support the importance of the outsourcing model of P acquisition in the root economics space framework.Inadvertent varietal selection in the last decades,resulting in thinner roots and a lower benefit from AMF,has led to a lower productivity of cotton varieties at moderate P supply (i.e.,when mycorrhizal,the average biomass of older varieties 5.0 g per plant vs.biomass of newer varieties 4.4 g per plant),indicating the need to rethink cotton breeding efforts in order to achieve high yields without very high P input.One feasible way to solve the problem of inadvertent varietal selection for cotton is to be aware of the trade-offs between the root do-it-yourself strategy and the outsourcing towards AMF strategy,and to consider both morphological and mycorrhizal root traits when breeding cotton varieties.
文摘The hydrophobic cuticle encasing the fruit skin surface plays critical roles during fruit development and post-harvest.Skin failure often results in the fruit surface cracking and forming a wound-periderm tissue made of suberin and lignin.The factors that make the fruit skin susceptible to cracking have yet to be fully understood.Herein,we investigated two varieties of chili peppers(Capsicum annuum L.),Numex Garnet,whose fruit has intact skin,and Vezena Slatka,whose fruit has cracked skin.Microscopical observations,gas chromatography-mass spectrometry,biochemical and gene expression assays revealed that Vezena Slatka fruit form a thicker cuticle with greater levels of cutin monomers and hydroxycinnamic acids,and highly express key cutin-related genes.The skin of these fruit also had a lower epidermal cell density due to cells with very large perimeters,and highly express genes involved in epidermal cell differentiation.We demonstrate that skin cracking in the Vezena Slatka fruit is accompanied by a spatial accumulation of lignin-like polyphenolic compounds,without the formation of a typical wound-periderm tissues made of suberized cells.Lastly,we establish that skin cracking in chili-type pepper significantly affects fruit quality during post-harvest storage in a temperature-dependent manner.In conclusion,our data highlight cuticle thickness and epidermal cell density as two critical factors determining fruit skin susceptibility to cracking in chili-type pepper fruit.
文摘Coffee production has decreased due to environmental and management factors. The current plantations are old and unproductive, also due to the rust problem, caused by the fungus Hemileia vastatrix Berk & Br. Furthermore, the shade in the production systems has decreased with the consequent increase in soil erosion, in addition to the increase in agrochemicals. Currently, the planting of new varieties with resistance to the fungus is increasing. Furthermore, it has been shown that various biofertilized perennial crops in nursery favor their growth. In this study, the effect of applying two beneficial microorganisms, Rhizophagus intraradices and/or Azospirillum brasilense, to the planting of four varieties of Coffea arabica L. was evaluated. The coffee varieties marseillase, geisha, sarchimor and costa rica 95 were established in bags with the following treatments: 1) control, 2) R. intraradices, 3) A. brasilense, 4) R. intraradices + A. brasilense. Morphological and physiological yield components were recorded 168 days after transplanting. Data was analyzed statistically and differences between treatments were compared according to Tukey (p ≤ 0.05). The results indicate that individual or combined biofertilization of microorganisms favors dry matter allocation compared to the control and the same is differentially assigned to the stem and root. The Specific Leaf Area (SLA) also showed differential response between applications of the microorganisms, in two varieties it increased when they were applied alone and in the others when they were applied together.
基金Supported by Science and Technology Agriculture Project of Shanghai Municipal Commission of Agriculture and Rural Affairs[Hu Nong Ke Tui Zi(2019)No.1-8]Science and Technology Innovation Action Plan of the Science and Technology Commission of Shanghai Municipality(19DZ1203501).
文摘[Objectives]To study the introduction performance of pomegranate(Punica granatum)varieties in Shanghai area.[Methods]In this experiment,five pomegranate varieties were introduced,namely‘American 002’pomegranate,‘Huohulu’pomegranate,‘Wanli No.1’pomegranate,‘Yicheng Hongpitian’pomegranate,and‘American Qingpisuan’pomegranate.Then,using these five varieties,various biological traits such as phenology and fruit quality of pomegranate,as well as stress resistance such as heat resistance and cold resistance were studied.[Results]Five varieties of pomegranates began to mature in succession in early September;the smallest single fruit weight was 90 g,and the largest was 110 g;the plants grew fast,the plants were strong,the flowers were single petal,and plants bore fruits which were ornamental and edible.In addition,the pomegranates of these five varieties had good water tolerance and heat resistance,and good cold resistance.[Conclusions]This study is intended to provide a certain reference for the introduction of pomegranate varieties,and also provide a practical basis for the large-scale planting of pomegranate.
文摘It has been observed that farmers adopt only a small number of the “improved” cultivars. A nationwide germplasm collection exercise in February 2018 provided the opportunity to collect indigenous technical knowledge (ITK) of the diversity of cassava varieties in terms of: their morphology, growth characteristics, uses (of tubers and leaves) and desirable characteristics. The objective is to see to what extent the objectives of the plant breeders are consistent with what farmers’ value. We performed 405 structured and semi-structured interviews with informants who were selected based on “purposive household sampling”. We found a considerable turn-over in cassava varieties, just over a third (45) have been in cultivation for at least 40 years, however, since the end of the civil war an additional 25 varieties are cultivated, while others varieties seem to have disappeared. One major issue with estimating turnover of varieties is whether the same variety might have several local names, and conversely the same name may be applied to different cultivars. Farmers overwhelmingly use ITK to select and preserve cassava germplasm for future use. Farmers have a clear preference for: sweet taste, high yield, early maturity and easy cooking and preferentially adopt cultivars that have those qualities. Cassava is primarily a human food eaten boiled or fried, some are processed into fufu and gari, and uses as livestock feed and medicine are reported but at low levels. The information produced during this study could help plant breeders choose selection criteria that will ensure their efforts are adopted and sustainable, the importance of preserving the genetic resources of local cultivars is also highlighted.
文摘The literature highlights that a severe infection by the fungus Colletotrichum truncatum may be capable of inflicting considerable damage to seeds after harvest, potentially affecting their chemical composition and physiological quality. Taking into account that currently there is no categorization in terms of susceptibility and tolerance on this pathogen, the present work is presented with the main objective of “Evaluate the influence of Pathogenicity of C. truncatum on the physiological quality (germination, vigor, viability) and biochemical components in different varieties of soybean seeds (Glycine max)” most planted in the region. The work was carried out in the Agrotec laboratory, located in the Municipality of San Alberto (Alto Paraná), using a completely randomized experimental design, with AxB factorial arrangement, where A indicates ten most planted soybean varieties in the region and B with or without artificial inoculation of Colletotrichum truncatum, with twenty treatments and four repetitions. The variables evaluated were: germination, vigor, viability and chemical composition. The data were subjected to analysis of variance and the Tukey test at 5% error. The results showed a significant statistical difference, accepting the alternative hypothesis proposed “The pathogenicity of Colletotrichum truncatum influences the physiological quality (germination, vigor, viability) and biochemical components (saturated and unsaturated fatty acids) in different varieties of soybean seeds (Glycine max)”.
文摘Improved rice varieties(IRVs)play a significant role in establishing food security and improving livelihood in the Global South since its introduction in the 1960s.However,the adoption of new IRVs has remained relatively low.This low adoption poses a challenge to rice-producing and consuming countries as they are increasingly threatened by production shortages,malnutrition,and poor rice quality.Many empirical studies have attempted to identify the determinants influencing the adoption of IRVs by distinguishing the characteristics between adopters and non-adopters.This review showed a consensus on the important determinants influencing the adoption of IRVs in the Global South.Findings synthesized from 99 studies suggested that variables(farm size,education,information access and farm location)examined extensively are not necessarily the most important determinants of adoption when undertaking a weighted analysis.Terrain,source of seed and technology-related attributes(perceived yield,maturity,ease of use,marketability and technical efficiency)are more important determinants of adoption,with determinants changing according to adoption type(probability or intensity of adoption),variety type and region.The recommendations for future adoption studies include:incorporating more technology-specific variables,increasing research for overlooked regions and variety types,shifting away from predominant static analysis by capturing the dynamics of the adoption process,and considering the potential biases in analyses.This review will facilitate the development of targeted interventions and policies that promote IRV adoption in the Global South.
文摘[Objectives]This study was conducted to select suitable medium-sized watermelon varieties for early spring cultivation in Beijing.[Methods]Seven watermelon varieties were collected,including Beinong Tianjiao 2,Beinong Tianjiao,Hongfuji,Yongfeng 1,Beinong Futian,Beinong Shijia,and Beinong Jinxiu,and Jingxin 2 was used as the control check(CK).The growth period,morphological traits,yield traits and fruit quality of the tested varieties were investigated.[Results]Beinong Tianjiao 2 had an earlier maturation stage,a fruit development period of 38 d and a total growth period of 118 d.It showed stable growth,with a single fruit weight of 7.56 kg,a fruit setting rate of 0.99 per plant,and a yield of 83076.9 kg/hm~2,which ranked,respectively,second,first,and second among all tested varieties,and were significantly superior to the CK.Furthermore,this variety had thin and tough peel,a bright red flesh color,high central sugar content,loose and crisp flesh,and a good taste.[Conclusions]It is preliminarily believed that it is suitable for early spring watermelon production in Beijing area.
基金Supported by Special Crop Innovation Team of Beijing(BAIC04-2022)。
文摘[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing.
文摘[Objectives]To study the adaptability of introduced pear.[Methods]Five pear varieties,"Aidang"pear,"Taiwan Zaomi"pear,"Cuiguan"pear,"Tianjin Yali"pear and"Zaosheng Xinshui"pear,were introduced.Then,using these five varieties,the phenology of pear trees,various characters of fruit,stress resistance(heat tolerance and cold tolerance)of varieties were studied.[Results]The plants of 5 varieties of pear trees grew fast and were robust;in late March,it went into the flowering period;"Aidang"pear fruit had a certain number of stone cells;"Taiwan Zaomi"pear had the highest sweetness;"Cuiguan"pear had the largest fruit;these five varieties of pear trees had good water resistance,heat resistance and cold resistance.[Conclusions]This study can provide a reference for the introduction of pear trees,and can also provide a practical basis for the large-scale planting of pear trees.
文摘[Objectives]To select zucchini varieties suitable for cultivation in Zibo City and test its high-yield cultivation techniques.[Methods]Six zucchini varieties were introduced,and their commercial quality and yield were determined.[Results]The yield of Shengfeier,Xiuyu 170 and Xihulu 309 increased by 11.4%,6.9%and 4.6%,respectively compared with S68(control),and zucchini was straight,looked pleasing to the eye,and had strong disease resistance.[Conclusions]The zucchini varieties were selected and the high-quality,high-yield and high-efficiency cultivation techniques were integrated.
文摘This experiment aims to increase sweet pepper production sustainably by using manures and a combination of manure and fertilizer. Manures are well known to improve soil health and maintain crop production for a relatively long period. This study was conducted under a tunnel house at the National Agricultural Research and Extension Institute at Mon Repos East Coast Demerara, Guyana. Plots were arranged according to strip plot design with two treatments (Aristotle and Sunsation), four rates (R1: 0 g/plant), (R2: 350 kg NPK/ha + 10 t vermicompost/ha), (R3: 10 t poultry manure/ha + 10 t vermicompost/ha and (R4: 350 kg NPK/ha + 10 t poultry manure/ha) and replicated thrice. These nutrients were applied in a split application at four weeks before planting, and four, eight, and twelve-week intervals after planting. The varieties did not differ from one another for the vegetative parameters tested. Plants treated with Rate 2 achieved significantly better growth parameters such as plant height, plant spread, and number of branches than the other rates. Sunsation obtained a significantly higher yield of 21.4 t/ha at the 5% level as compared to Aristotle (19.9 t/ha). The various rates recorded significant differences in yield. Rate 2 obtained a significantly higher yield of 32.8 t/ha followed by Rate 4 with 24.9 t/ha, then Rate 3 (17.0 t/ha). The lowest yield of 7.8 t/ha was attained by Rate 1. The interaction of varieties and rates showed statistically significant differences in yield. The interaction of Sunsation and Aristotle with Rate 2 achieved a superior yield of 34.8 t/ha and 30.7 t/ha respectively than other rates. Rate 4 also obtained significant interaction with Sunsation and Aristotle to achieve a yield of 25.7 t/ha and 24.1 t/ha respectively than Rate 3. Rate 3 interacted significantly with Sunsation and Aristotle and obtained a yield of 16.5 t/ha and 17.5 t/ha compared to Rate 1. Rate 1 achieved the least interaction for both varieties tested. Rates differed significantly for fruit shelf-life at room temperature. Fruits obtained from Rate 3 recorded a significantly longer fruit shelf-life of 14.7 days for 50% decay when stored at room temperature (30.3˚C) than other rates. The lowest fruit shelf-life of 7.7 days was obtained from Rate 1. This study indicated that the Sunsation variety is better to cultivate because of superior improvement in growth and yield attributes. The application of Rate 2 can considerably increase yield and when combined with Sunsation variety superior yield and yield attributes can be obtained.
基金financially supported by Natural Key R&D Program of China(No.2018YFC1707000).
文摘Objective Using the stable isotope ratio method for the authenticity identification and variety identification of refined honey.Methods In this paper,a total of 17 samples of different varieties of refined honey were used to obtain refined honey proteins by precipitation with sodium tungstate solution and sulphuric acid solution.The isotope mass spectrometer was used to simultaneously detect theδ^(13)C values of refined honey proteins and refined honey as well as theδ^(18)O andδ^(2)H values of refined honey,processed of the results obtained,analysed the authenticity of the samples and conduct a variety identification study.Results Tested of the resulting honey samples,the results showed that four batches of refined honey did not up to standard,two batches of C-4 vegetable syrup were detected as adulterated,and two batches of protein were not detected.Theδ^(18)O andδ^(2)H values of refined honey were also found to be effective in distinguishing the varietal origin of refined honey to a certain extent.Conclusions The stable isotope ratio method is useful in the authenticity identification of refined honey,and provides new ideas to further promote the authenticity of refined honey and variety identification research.
文摘English varieties have grown up in different parts of the world. The traditional prototype paradigm of ELT,which assumed that a non-native learner learned English in order to communicate with a native speaker,no longer represents the primary context of the use of English today. Therefore,in ELT,besides learning standard English,sensitivity to English varieties should be cultivated so as to promote communicative competence.
文摘Learner's motivation is very important in learning process and learning result. It can be divided into different varieties. The positive factors which can influence learner's motivation can play a vital role in College English teaching. In college English learning and teaching, teachers should adopt suitable teaching strategies and methods to realize these positive factors in order to im-prove college students English learning.
文摘This paper focuses on the nativization of English in China,using Pidgin English as a case study to put Chinese English variants under the theoretical framework of eco-linguistics,and put the ecological environment such as species competition,coexistence and co-evolution,etc.The natural phenomenon is compared with the existence of language phenomenon in the development process of China English represented by Pidgin English.The study found that as the spark of the collision of the two mainstream languages of Chinese and English,the Chinese English varieties play a very important role in the exchange and enrichment of the two languages and cultures.Although academic circles have different attitudes and opinions on Chinese English variants,their existence and development conform to the law of the development of things and are also inevitable in historical development.Blindly ignoring their objective existence will definitely bring adverse effects on the ecological balance of the language.We should face up to the existence of Chinese English variants,comply with the law of language development,and allow it to develop naturally,and make efforts to protect the ecological balance of the world’s languages.
基金financed by the Special Program of Super Rice of Ministry of Agriculture, China (02318802013231)the National Public Services Sectors (Agricultural) Research Projects, Ministry of Agriculture, China (201303102)the Great Technology Project of Ningbo, China (2013C11001)
文摘Understanding the morphological and physiological traits associated with improved filling efficiency in large-panicle rice varieties is critical to devise strategies for breeding programs and cultivation management practices.Information on such traits,however,remains limited.Two large-panicle varieties with high filled-grain percentage(HF) and two check large-panicle varieties with low filled-grain percentage(LF) were field-grown in 2012 and 2013.The number of spikelets per panicle of HF and LF both exceeded 300,and the filled-grain percentage(%) of HF was approximately 90,while that of LF was approximately 75 over the two years.The results showed that when the values were averaged across two years,HF yielded 12.91 ha^(-1),while LF yielded 11.01 ha^(-1).HF had a greater leaf area duration,biomass accumulation and transport of carbohydrates stored in the culm to the grains from heading to maturity compared with LF.HF exhibited a higher leaf photosynthetic rate,more green leaves on the culm,and higher root activity during filling phase,especially during the middle and late filling phases,in relative to LF.The length of HF for upper three leaves was significantly higher than that of LF,while the angle of upper three leaves on the main culm was less in both years.Meanwhile,specific leaf weight of HF was significantly higher when compared with LF.In addition,the grain filling characteristics of HF and LF were investigated in our study.Our results suggested that a higher leaf photosynthetic rate and root activity during filling phase,greater biomass accumulation and assimilate transport after heading,and longer,thicker and more erect upper three leaves were important morphological and physiological traits of HF,and these traits could be considered as selection criterion to develop large-panicle varieties with high filled-grain percentage.
基金supported by Forestry Science&Technology Innovation Project of Shandong Province(LYCX01-2018-03)Fund for the Development of Guidelines for the Conduct of Tests for Distinctness,Uniformity and Stability(201519)
文摘Distinctness,uniformity and stability(DUS)Test Guidelines for new varieties of Viburnum L.were developed according to the principles and requirements of the International Union for the Protection of New Varieties of Plants(UPOV)and China.The development processes,including selection and determination of testing characteristics,determination of expression states of characteristics,selection of example varieties,determination of the order of characteristics,and assessment of distinctness,uniformity and stability,are described in this paper.There were 54 testing characteristics:24 qualitative characteristics(QL),15 quantitative characteristics(QN),15 pseudoqualitative characteristics(PQ)and 34 example varieties in the DUS Test Guidelines.Among the 54 testing characteristics,20 were asterisked and 34 were non-asterisked.Seven were selected for variety groupings and 18 were adopted in the Technical Questionnaire.The development of these DUS Test Guidelines will be useful for the application and protection of new Viburnum varieties.The Guidelines will provide technical support for DUS testing of Viburnum and serve as a reference for the development of new varieties in other countries.
基金This work was supported by the Ministry of Science and Technology of the People’s Republic of China(Grant No.2013BAD01B0702).
文摘Cymbidium has been artificially domesticated for centuries in Asia,which produced numerous cultivated varieties.Flowers with stamenoid tepals or those with multiple tepals have been found in different species of Cymbidium;however,the molecular basis controlling the formation of these phenotypes is still largely unknown.Previous work demonstrated that AGAMOUS/AG lineage MADS genes function in floral meristem determinacy as well as in reproductive organs development in both dicots and monocots,indicating a possible relationship with the origin of two flower varieties in Cymbidium.Here,we characterized and analyzed two AG lineage paralogues,CsAG1 and CsAG2,from Cymbidium sinense,both of which were highly expressed in the gynostemium column of a standard C.sinense.Interestingly,we detected ectopic expression of CsAG1 rather than CsAG2 in all floral organs of a stamenoid-tepal variety and significant down-regulation of CsAG1 in a variety with multiple tepals.Over-expression of CsAG1 in wild type Arabidopsis resulted in petal-to-stamen homeotic conversion,suggesting a conserved C-function of CsAG1 in the development of Cymbidium flower.Altogether,our results supported a hypothesis that disruption of a single AG-like factor would be associated with the formation of two domesticated varieties in C.sinense.
