Pod shattering,while a natural mechanism for seed dispersal,is an undesirable agronomic trait in rapeseed(Brassica napus L.)that complicates mechanical harvesting.It typically causes yield losses of 5%-15%,which can b...Pod shattering,while a natural mechanism for seed dispersal,is an undesirable agronomic trait in rapeseed(Brassica napus L.)that complicates mechanical harvesting.It typically causes yield losses of 5%-15%,which can be further worsened under dry and hot conditions.As most of the modern rapeseed cultivars remain susceptible to shattering,enhancing pod shattering resistance(PSR)is important to safeguard global rapeseed production.Significant progresses have been made in elucidating the molecular and genetic mechanisms of silique dehiscence in the model plant Arabidopsis and pod shattering in rapeseed.This review firstly summarizes the genetic network controlling silique dehiscence in Arabidopsis,which is largely conserved in closely related Brassica species.We then synthesize discoveries from both forward and reverse genetic studies in rapeseed.Finally,the major challenges and future prospects in PSR research and breeding are discussed in depth.展开更多
Cotton,a crucial commercial fibre crop,depends heavily on seed-associated characteristics like germination rate,vigour,and resistance to post-harvest deterioration for both production and lint quality.Serious cellular...Cotton,a crucial commercial fibre crop,depends heavily on seed-associated characteristics like germination rate,vigour,and resistance to post-harvest deterioration for both production and lint quality.Serious cellular damage dur-ing post-harvest processes such as delinting,prolonged seedling emergence periods,decreased viability,increased susceptibility to infections,and lipid peroxidation during storage pose serious problems to seed quality.The perfor-mance of seeds and total crop productivity are adversely affected by these problems.Traditional methods of seed improvement,like physical scarification and seed priming,have demonstrated promise in raising cotton seed vigour and germination rates.Furthermore,modern approaches including plasma therapies,magnetic water treatments,and nanotechnology-based treatments have shown promise in improving seed quality and reducing environmen-tal stresses.By offering sustainable substitutes for conventional approaches,these cutting-edge procedures lessen the need for fungicides and other agrochemicals that pollute the environment.This review explores various con-ventional and emerging strategies to address the detrimental factors impacting cotton seed quality.It emphasizes the importance of integrating classical and advanced approaches to enhance germination,ensure robust crop estab-lishment,and achieve higher yields.In addition to promoting sustainable cotton production,this kind of integration helps preserve the ecosystem and create resilient farming methods.展开更多
Pinus densiflora is a pine species native to the Korean peninsula,and seed orchards have supplied mate-rial needed for afforestation in South Korea.Climate vari-ables affecting seed production have not been identified...Pinus densiflora is a pine species native to the Korean peninsula,and seed orchards have supplied mate-rial needed for afforestation in South Korea.Climate vari-ables affecting seed production have not been identified.The purpose of this study was to determine climate variables that influence annual seed production of two seed orchards using multiple linear regression(MLR),elastic net regres-sion(ENR)and partial least square regression(PLSR)mod-els.The PLSR model included 12 climatic variables from 2003 to 2020 and explained 74.3%of the total variation in seed production.It showed better predictive performance(R2=0.662)than the EN(0.516)and the MLR(0.366)mod-els.Among the 12 climatic variables,July temperature two years prior to seed production and July precipitation after one year had the strongest influence on seed production.The time periods indicated by the two variables corresponded to pollen cone initiation and female gametophyte development.The results will be helpful for developing seed collection plans,selecting new orchard sites with favorable climatic conditions,and investigating the relationships between seed production and climatic factors in related pine species.展开更多
Seed aging tolerance during storage is generally an important trait for crop production, yet the role of small auxin-up RNA genes in conferring seed aging tolerance is largely unknown in rice. In this study, one small...Seed aging tolerance during storage is generally an important trait for crop production, yet the role of small auxin-up RNA genes in conferring seed aging tolerance is largely unknown in rice. In this study, one small auxin-up RNA gene, OsSAUR33, was found to be involved in the regulation of seed aging tolerance in rice. The expression of OsSAUR33 was significantly induced in aged seeds compared with unaged seeds during the seed germination phase. Accordingly, the disruption of OsSAUR33 significantly reduced seed vigor compared to the wild type(WT) in response to natural storage or artificial aging treatments. The rice OsSAUR33 gene promotes the vigor of aged seeds by enhancing their reactive oxygen species(ROS) level during seed germination, and the accumulation of ROS was significantly delayed in the aged seeds of Ossaur33 mutants in comparison with WT during seed germination. Hydrogen peroxide(H_(2)O_(2)) treatments promoted the vigor of aged seeds in various rice varieties. Our results provide timely theoretical and technical insights for the trait improvement of seed aging tolerance in rice.展开更多
Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.Howev...Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.However,the physiological mechanisms of seed abscission in T.grandis remain poorly understood.To gain insight into the relationships between carbohydrate status and seed abscission,three-year-old seed-bearing branches were taken as representative materials for the entire tree.Furthermore,the time course of changes in the photosynthetic rate and the non-structural carbohydrate(NSC)dynamics were monitored in the main sources(the one-year-old and two-year-old shoots),and the dry weight and NSC levels of sinks(the seeds,current female cone cluster,and current vegetative cluster)across all seed development stages were recorded.The cumulative seed abscission rate significantly increased,reaching 91.5%from 0 to 72 days after seed protrusion time(SPT).NSC levels in the main sources significantly decreased by 56%-79%,accompanied by a significantly increased photosynthesis rate of 17.1%-49.1%during that period and increased NSC levels in the three sinks.The gene expression level of cell wall invertase(TgCWIN)was significantly correlated with sucrose,fructose,and glucose levels.The carbon storage capacity of the main sources significantly decreased from 6.03 to3.14 mmol C·d^(-1),with a stable photosynthetic capacity,from 0 to 72 days after SPT,whereas the carbon demand of the three sinks showed a continuously increasing trend from 3.14 to 7.71 mmol C·d^(-1).In addition,sucrose supplementation significantly decreased the cumulative seed abscission rate.These results suggest that storage carbohydrates play a major role in the regulatory mechanism of seed abscission in T.grandis.Our study provides a theoretical basis for improving T.grandis yield through establishing a better carbon balance between sources and sinks using timely fertilization or proper pruning procedures.展开更多
[Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used...[Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used to coat the seeds of two varieties(Taiyou 390 and Zhenliangyou 8612)of hybrid rice with different"grey-matter"content(5%,15%,25%),and the results were investigated and compared.[Results]The combinations of treatment B(seed coating agent A+Linong)and treatment C(Manshijin+seed coating agent A)could significantly improve indexes including seed germination potential,germination rate,seed vigor,seedling height,fibrous roots and fresh weight of the two varieties with a"grey-matter"content greater than 15%,but had no significant effects on main root length,dry weight,leaf number and tiller number,and the effects of treatment B was better than those of treatment C.That is to say,mixed seed coating agent B(seed coating agent A+Linong)was suitable for use as a seed coating agent to improve the quality of"grey-matter"seeds.[Conclusions]This study provides a reference plan for the safe use of mixed seed batches with"grey-matter"deterioration.展开更多
Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent stu...Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent studies in crops have uncovered numerous genes that control seed size and weight,many of which function by modulating phytohormone biosynthesis,metabolism,or signaling pathways.This review provides a comprehensive overview of the genetic and molecular mechanisms by which phytohormones regulate seed size and weight and their cross-talks in modulating seed size.We highlight the functional conservation and divergence of homologous genes that control seed size across species.A particular focus is placed on those genes that have promising potential for yield improvement.Finally,we discuss current challenges in phytohormone regulation of seed size and molecular design breeding strategies for translating this knowledge into crop improvement.展开更多
Evaluation of seed quality is the key to seed distributing and seeding of Glycyrrhiza uralensis Fisch,as an important species for pharmacy and soil conservation.Here,we study the effects of light and temperature on se...Evaluation of seed quality is the key to seed distributing and seeding of Glycyrrhiza uralensis Fisch,as an important species for pharmacy and soil conservation.Here,we study the effects of light and temperature on seed germination and mechanical and chemical scarification on breaking the seed coat.Seeds were collected in 2004,2005,and 2006,placed in Petri dishes,and incubated at constant temperature 20,25,and 30℃,and alternating temperature 15-25,20-30,15-30,and 20-35℃under either an 8h photoperiod or total darkness for 28 consecutive days.Different methods were used to break the dormancy owing to hard seededness in this species such as chemical scarification by immersing in concentrated sulphuric acid for 5,10,15,20,25,30,45,and 60 min,in 0.2%KNO3 solution to saturate the seedbed,and prechilling for 7 d at 7℃and mechanical scarification by cutting.The results showed that alternating temperature at 20-30℃with 8 h photoperiod and 16 h darkness was optimum for G.uralensis seed germinating in the laboratory.Hard seeds were broken by concentrated sulphuric acid soaking or mechanical scarification by cutting.Germination of seeds harvested in two different years was both promoted by immersing for 30-45 min in concentrated sulphuric acid.KNO3 solution was ineffective for reducing hard seeds.During seed germinating,the first count was on the 7th day and the last count was on the 14th day.展开更多
Wheat is a strategic crop for food security in Pakistan with predominance of smallholder farmers. Farmer-saved seed （FSS） is used nearly by 75% of farmers for wheat production. Frequent variety or seed replacement i...Wheat is a strategic crop for food security in Pakistan with predominance of smallholder farmers. Farmer-saved seed （FSS） is used nearly by 75% of farmers for wheat production. Frequent variety or seed replacement is uncommon even among large-scale farmers, and certified seed （CS） is mostly bought to verify the value of new varieties. Replacing old and obsolete varieties by new high yielding disease resistant varieties is key to transferring new genetic gains to farmers. For the first time in Pakistan, on-farm factorial experiments involving seven new and five old wheat varieties and their corresponding CS and FSS were conducted. A total of 49 farmers representing major wheat cropping patterns throughout the country participated in these trials in the 2014 and 2015 wheat growing seasons. Analysis of variance revealed that there was highly significant difference between wheat varieties and between seed classes. New variety ＋ CS gave 33.8% more grain yield as well as higher marginal return over farmers＇ variety ＋ FSS. Grain yield and returns from new variety ＋ FSS and farmers＇ variety ＋ CS were at par. Scientific knowledge generated in this research demonstrated that use of CS ＆new wheat varieties is best option, while growing new varieties with FSS is a second choice for the advantages accruing from their built-in genetic traits of economic importance over growing CS of old and obsolete varieties. Having more flexible seed system will help accelerate the delivery of new genetic gains to farmers＇ fields.展开更多
Brassica napus,one of the most important oil crops cultivated globally,is severely impacted by prolonged soil contamination with cadmium(Cd),resulting in decreased yields and poor seed quality.This crop exhibits a hig...Brassica napus,one of the most important oil crops cultivated globally,is severely impacted by prolonged soil contamination with cadmium(Cd),resulting in decreased yields and poor seed quality.This crop exhibits a high adsorption capacity for Cd,making creating seed resources with low Cd accumulation an essential strategy to alleviate this challenge.To address this issue,we genetically edited BnaNRAMP1 in B.napus by targeting three different exon regions,resulting in new germplasm resources with significant differences in Cd accumulation capacity and unaffected yield.Among these,the mutant K140-22,specifically targeting the 7th exon,is distinguished by its substantially reduced Cd accumulation.Further,enzyme assays of the antioxidant defense system in both roots and shoots of K140-22 revealed its enhanced antioxidant activity,which contributes to elucidating the molecular mechanisms of plant tolerance to heavy metal stress.Remarkably,this mutant also maintained equivalent agronomic traits and seed quality,which highlights its potential as a germplasm resource for rapeseed breeding for low Cd accumulation and elevating rapeseed economic value in Cd-contaminated soil.展开更多
We analyzed 17 seed sources(seed stands)ofPinus wallichiana for variations present in cone and seed characters,scattered over natural distribution in north-west Himalayan states(Uttarakhand and Himachal Pradesh)of Ind...We analyzed 17 seed sources(seed stands)ofPinus wallichiana for variations present in cone and seed characters,scattered over natural distribution in north-west Himalayan states(Uttarakhand and Himachal Pradesh)of India.The significant variations were observed in cone weight,cone length,cone width,seed length,seed width,seed weight,seed germination,radicle length,and plumule length among different seed sources of the species.Significant positive correlation between seed weight,cone weight and cone width showed that seed weight in the species depend more on the cone size.Seed germination was also positively correlated with seed weight,cone weight and radicle length in the study.The estimates of variability with regard to genetic parameters for seed weight,seed germination,cone length,cone width,cone weight showed wide range of variation in the study.Seed weight showed high heritability values coupled with maximum genetic gain.Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i,e.genotypic and environmental interaction,The study suggests that the seed weight should be given the top priority for the further improvement of this species.展开更多
To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic tra...To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic traits,resistance,and yield traits.The results showed that the six early-maturing rapeseed varieties exhibited strong pre-winter growth,with the number of green leaf on the main stem ranging from 9.0 to 11.6,the total leaf number of main stem from 11.8 to 14.2,the maximum leaf length on main stem from 41.28 cm to 47.54 cm,the maximum leaf width from 12.02 cm to 13.38 cm,and the rhizome thickness from 20.64 mm to 25.82 mm.The order of green leaf,total leaf,maximum leaf length,and rhizome thickness from high to low across varieties was ZY1>ZY2>ZY3>ZY4>ZY5>ZY6,while the maximum leaf width followed ZY2>ZY1>ZY3>ZY4>ZY5>ZY6.Compared with other varieties,ZY1 and ZY2 had earlier bolting,initial flowering,final flowering,and harvesting times.The growth periods of the varieties were 183-189 d,with ZY1 being the shortest(183 d)and ZY2 following(185 d).Resistance investigations showed that ZY1 had the lowest freeze damage rate(13%)and freeze damage index(0.043),followed by ZY2(15%and 0.060).No Sclerotinia stem rot was observed at the seedling stage,while all varieties developed the disease at maturity;ZY1 had the lowest incidence(15%)and disease index(0.050),followed by ZY2(18%and 0.070).In terms of yield traits,the yield per plant of the six varieties ranged from 11.46 g to 14.53 g,with ZY1 being the highest(14.53 g)and ZY2 following(13.42 g).In conclusion,ZY1 and ZY2 exhibited vigorous pre-winter growth,early bolting and flowering,short growth periods,strong freeze and disease resistance,and high yield per plant,making them ideal materials for early-maturing rapeseed breeding.展开更多
Pre-harvest desiccation may increase the efficiency of seed production. Field studies were conducted to determine the effects of diquat, paraquat, and ethephon applications on grain moisture, grain weight, and seed ge...Pre-harvest desiccation may increase the efficiency of seed production. Field studies were conducted to determine the effects of diquat, paraquat, and ethephon applications on grain moisture, grain weight, and seed ger- mination of hybrid rice Yanliangyou 88 （Oryza sativa ssp. indica） and conventional rice Wuyunjing 7 （Oryza sativa ssp. japonica）. In 2013, we tested 12 treatments applied at four weeks （Yanliangyou 88） and six weeks （Wuyunjing 7） after heading. Results showed that reductions in moisture content were significant two and four days after chemical ap- plication. Chemical applications had no adverse effects on lO00-grain weight, germination percentage, or germination index, but there were negative effects on the percentage of normal seedlings. Desiccation effects increased with increase in the period after application, while the effect of ethephon combined with diquat or paraquat on desiccation was limited compared with that of diquat or paraquat alone in a short period after application. In 2013, chemical ap- plications reduced the moisture content by from 0.5% to 6.4%, the germination percentage by from 0% to 3.3%, and the percentage of normal seedlings by from 13.3% to 100.0%. Among the treatments, diquat applied at 120 g/ha resulted in effective desiccation with fewer negative effects on grain weight and seed germination in 2013 and 2014. Therefore, diquat may have potential as a pre-harvest chemical desiccation treatment for rice. These results may provide a basis for developing and implementing protocols for large scale field trials.展开更多
Rice(Oryza sativa L.),a thermophilic crop,is highly sensitive to cold stress,particularly during the seedling stage.Developing cold-tolerant rice varieties is a possible strategy to mitigate yield losses caused by low...Rice(Oryza sativa L.),a thermophilic crop,is highly sensitive to cold stress,particularly during the seedling stage.Developing cold-tolerant rice varieties is a possible strategy to mitigate yield losses caused by low temperatures.However,few genes for cold tolerance have been identified.In this study,we identified OsALA4(Aminophospholipid ATPase 4),encoding a plasma membrane-localized P4-ATPase,from a chromosomal segment substitution line(CSSL-K2832-2)harboring cold-tolerance QTL qLTS5(Low Temperature Sensitive 5).Genetic and subcellular localization analyses revealed that OsALA4 regulates cold tolerance by maintaining plasma membrane fluidity and cellular homeostasis.Physiological assessments showed that OsALA4 reduces malondialdehyde(MDA),electrolyte leakage,reactive oxygen species(ROS),and cell death under cold stress.Promoter activity assays indicated that stronger OsALA4 expression in Nipponbare(OsALA4Nip)correlated with enhanced cold tolerance.Further experiments demonstrated that SNP sites within the promoter regions(-1500 bp to-700 bp)of OsALA4Nipand OsALA49311influenced their activity.This study highlights Os ALA4 as a valuable genetic target for breeding cold tolerant rice.展开更多
Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the e...Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses： modern cold room （5℃）, mud house （15℃）, concrete block house （17℃ or corrugated iron house （20℃） for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation （p 0.01） in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room （41%） and the mud house （38%） maintained the same level of germination as the intitial germination of the seedlotds （42%）. The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots （r 0.80; p 0.01）. Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room （5℃） up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level.展开更多
Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforesta...Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforestation programmes for endangered species like Pterocarpus erinaceus. In the present study, to assess seedling germination and vigour in P. erinaceus as a function of seed size in two environments, 1080 seeds and 360 seedlings were evaluated at two separate sites in Côte d'Ivoire. The results show that large seeds had very high germination rates (up to 100%) and produced more vigorous plants better able to adapt to climate change. The maternal environment and seed size had a significant influence on seed germination (P < 0.05) and seedling development (P < 0.05) and biomass (P < 0.05). Seedlings were most successful at the site with a humid tropical climate (Daloa). Seedling leaves had the same resistance regardless of seed size and study site, but leaf moisture content was more stable in seedlings grown from medium and small seeds. These results will help guide conservation strategies for the species and are key factors for rural populations, loggers, and forest management structures for the silviculture of this species.展开更多
Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted i...Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar ＂Saxa＂, and four coriander seed lots, cultivar ＂Verdito＂ were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.展开更多
Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ...Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.展开更多
Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influ...Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. The latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including late embryogenesis abundant （LEA） protein, oligosaccharides and abscisic acid （ABA）. Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deformation and genes aberrance, and embryo protein degradation, etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and quantitative trait locus （QTL） analyses on seed-vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, whereas few physiological traits have been researched. It was concluded that, all of the QTL genetic characteristics of seed vigorincluding QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment, differed with plant species and used seed-vigor traits.展开更多
As a multicellular organism,rice flourishes relying on gene expression diversity among cells of various functions.However,cellular-resolution transcriptome features are yet to be fully recognized,let alone cell-specif...As a multicellular organism,rice flourishes relying on gene expression diversity among cells of various functions.However,cellular-resolution transcriptome features are yet to be fully recognized,let alone cell-specific transcriptional responses to environmental stimuli.In this study,we apply single-cell RNA sequencing to both shoot and root of rice seedlings growing in Kimura B nutrient solution or exposed to various abiotic stresses and characterize transcriptomes for a total of 237,431 individual cells.We identify 15 and 9 cell types in the leaf and root,respectively,and observe that common transcriptome features are often shared between leaves and roots in the same tissue layer,except for endodermis or epidermis.Abiotic stress stimuli alter gene expression largely in a cell type-specific manner,but for a given cell type,different stresses often trigger transcriptional regulation of roughly the same set of genes.Besides,we detect proportional changes in cell populations in response to abiotic stress and investigate the underlying molecular mechanisms through single-cell reconstruction of the developmental trajectory.Collectively,our study represents a benchmark-setting data resource of single-cell transcriptome atlas for rice seedlings and an illustration of exploiting such resources to drive discoveries in plant biology.展开更多
基金supported by Biological Breeding-National Science and Technology Major Project(2022ZD04008)the Jiujiang Municipal Key Research and Development Program(2025_001556)Lushan City Scientific and Technological Innovation Talents and Teams Program and Earmarked Fund for China Agricultural Research System(CARS-12)。
文摘Pod shattering,while a natural mechanism for seed dispersal,is an undesirable agronomic trait in rapeseed(Brassica napus L.)that complicates mechanical harvesting.It typically causes yield losses of 5%-15%,which can be further worsened under dry and hot conditions.As most of the modern rapeseed cultivars remain susceptible to shattering,enhancing pod shattering resistance(PSR)is important to safeguard global rapeseed production.Significant progresses have been made in elucidating the molecular and genetic mechanisms of silique dehiscence in the model plant Arabidopsis and pod shattering in rapeseed.This review firstly summarizes the genetic network controlling silique dehiscence in Arabidopsis,which is largely conserved in closely related Brassica species.We then synthesize discoveries from both forward and reverse genetic studies in rapeseed.Finally,the major challenges and future prospects in PSR research and breeding are discussed in depth.
基金the Indian Council of Agriculture Research-National Agriculture Higher Education Program(No.A4/003026/2023)to carry out this work during the international faculty training program at Nanyang Technological University,Singapore,under the Institution Development Plan.
文摘Cotton,a crucial commercial fibre crop,depends heavily on seed-associated characteristics like germination rate,vigour,and resistance to post-harvest deterioration for both production and lint quality.Serious cellular damage dur-ing post-harvest processes such as delinting,prolonged seedling emergence periods,decreased viability,increased susceptibility to infections,and lipid peroxidation during storage pose serious problems to seed quality.The perfor-mance of seeds and total crop productivity are adversely affected by these problems.Traditional methods of seed improvement,like physical scarification and seed priming,have demonstrated promise in raising cotton seed vigour and germination rates.Furthermore,modern approaches including plasma therapies,magnetic water treatments,and nanotechnology-based treatments have shown promise in improving seed quality and reducing environmen-tal stresses.By offering sustainable substitutes for conventional approaches,these cutting-edge procedures lessen the need for fungicides and other agrochemicals that pollute the environment.This review explores various con-ventional and emerging strategies to address the detrimental factors impacting cotton seed quality.It emphasizes the importance of integrating classical and advanced approaches to enhance germination,ensure robust crop estab-lishment,and achieve higher yields.In addition to promoting sustainable cotton production,this kind of integration helps preserve the ecosystem and create resilient farming methods.
基金supported by the National Institute of Forest Sciencethe R&D Program for Forest Science Technology (No.2022458B10-2224-0201) of the Korea Forest Service
文摘Pinus densiflora is a pine species native to the Korean peninsula,and seed orchards have supplied mate-rial needed for afforestation in South Korea.Climate vari-ables affecting seed production have not been identified.The purpose of this study was to determine climate variables that influence annual seed production of two seed orchards using multiple linear regression(MLR),elastic net regres-sion(ENR)and partial least square regression(PLSR)mod-els.The PLSR model included 12 climatic variables from 2003 to 2020 and explained 74.3%of the total variation in seed production.It showed better predictive performance(R2=0.662)than the EN(0.516)and the MLR(0.366)mod-els.Among the 12 climatic variables,July temperature two years prior to seed production and July precipitation after one year had the strongest influence on seed production.The time periods indicated by the two variables corresponded to pollen cone initiation and female gametophyte development.The results will be helpful for developing seed collection plans,selecting new orchard sites with favorable climatic conditions,and investigating the relationships between seed production and climatic factors in related pine species.
基金supported by the Key-Area Research and Development Program of Guangdong Province,China(2022B0202060006)the National Natural Science Foundation of China(32201838,32272157,32172052,and 31971995)+2 种基金the Natural Science Foundation of Guangdong Province,China(2023A1515012052)the Project of Sanya Yazhou Bay Science and Technology City,China(SCKJJYRC-2022-87)the Double First-class Discipline Promotion Project,China(2021B10564001)
文摘Seed aging tolerance during storage is generally an important trait for crop production, yet the role of small auxin-up RNA genes in conferring seed aging tolerance is largely unknown in rice. In this study, one small auxin-up RNA gene, OsSAUR33, was found to be involved in the regulation of seed aging tolerance in rice. The expression of OsSAUR33 was significantly induced in aged seeds compared with unaged seeds during the seed germination phase. Accordingly, the disruption of OsSAUR33 significantly reduced seed vigor compared to the wild type(WT) in response to natural storage or artificial aging treatments. The rice OsSAUR33 gene promotes the vigor of aged seeds by enhancing their reactive oxygen species(ROS) level during seed germination, and the accumulation of ROS was significantly delayed in the aged seeds of Ossaur33 mutants in comparison with WT during seed germination. Hydrogen peroxide(H_(2)O_(2)) treatments promoted the vigor of aged seeds in various rice varieties. Our results provide timely theoretical and technical insights for the trait improvement of seed aging tolerance in rice.
基金supported by grants from the National Science Foundation of China(Grant Nos.U20A2049 and 32271922)。
文摘Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.However,the physiological mechanisms of seed abscission in T.grandis remain poorly understood.To gain insight into the relationships between carbohydrate status and seed abscission,three-year-old seed-bearing branches were taken as representative materials for the entire tree.Furthermore,the time course of changes in the photosynthetic rate and the non-structural carbohydrate(NSC)dynamics were monitored in the main sources(the one-year-old and two-year-old shoots),and the dry weight and NSC levels of sinks(the seeds,current female cone cluster,and current vegetative cluster)across all seed development stages were recorded.The cumulative seed abscission rate significantly increased,reaching 91.5%from 0 to 72 days after seed protrusion time(SPT).NSC levels in the main sources significantly decreased by 56%-79%,accompanied by a significantly increased photosynthesis rate of 17.1%-49.1%during that period and increased NSC levels in the three sinks.The gene expression level of cell wall invertase(TgCWIN)was significantly correlated with sucrose,fructose,and glucose levels.The carbon storage capacity of the main sources significantly decreased from 6.03 to3.14 mmol C·d^(-1),with a stable photosynthetic capacity,from 0 to 72 days after SPT,whereas the carbon demand of the three sinks showed a continuously increasing trend from 3.14 to 7.71 mmol C·d^(-1).In addition,sucrose supplementation significantly decreased the cumulative seed abscission rate.These results suggest that storage carbohydrates play a major role in the regulatory mechanism of seed abscission in T.grandis.Our study provides a theoretical basis for improving T.grandis yield through establishing a better carbon balance between sources and sinks using timely fertilization or proper pruning procedures.
基金Supported by Changsha Science and Technology Major Project(kh2201219)Special Project of the Central Government Guiding Local Science and Technology Development(2023ZYC010)。
文摘[Objectives]This study was conducted to select suitable mixed seed coating agents for improving the quality of"grey-matter"hybrid rice seeds.[Methods]Three different mixed seed coating agents(A,B,C)were used to coat the seeds of two varieties(Taiyou 390 and Zhenliangyou 8612)of hybrid rice with different"grey-matter"content(5%,15%,25%),and the results were investigated and compared.[Results]The combinations of treatment B(seed coating agent A+Linong)and treatment C(Manshijin+seed coating agent A)could significantly improve indexes including seed germination potential,germination rate,seed vigor,seedling height,fibrous roots and fresh weight of the two varieties with a"grey-matter"content greater than 15%,but had no significant effects on main root length,dry weight,leaf number and tiller number,and the effects of treatment B was better than those of treatment C.That is to say,mixed seed coating agent B(seed coating agent A+Linong)was suitable for use as a seed coating agent to improve the quality of"grey-matter"seeds.[Conclusions]This study provides a reference plan for the safe use of mixed seed batches with"grey-matter"deterioration.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,China(XDB1090000 to S.J.)the National Key Research and Development Program of China,China(2021YFF1000202 and 2022YFF1002903 to Y.L.).
文摘Seed size is an important agronomic trait determining crop yield.Identifying key genes involved in seed size regulation and elucidating their molecular mechanisms are of great significance for crop breeding.Recent studies in crops have uncovered numerous genes that control seed size and weight,many of which function by modulating phytohormone biosynthesis,metabolism,or signaling pathways.This review provides a comprehensive overview of the genetic and molecular mechanisms by which phytohormones regulate seed size and weight and their cross-talks in modulating seed size.We highlight the functional conservation and divergence of homologous genes that control seed size across species.A particular focus is placed on those genes that have promising potential for yield improvement.Finally,we discuss current challenges in phytohormone regulation of seed size and molecular design breeding strategies for translating this knowledge into crop improvement.
基金the National Key Tech-nologies R&D Program during the 11th Five-Year Plan period(2006BAD04A04-02)
文摘Evaluation of seed quality is the key to seed distributing and seeding of Glycyrrhiza uralensis Fisch,as an important species for pharmacy and soil conservation.Here,we study the effects of light and temperature on seed germination and mechanical and chemical scarification on breaking the seed coat.Seeds were collected in 2004,2005,and 2006,placed in Petri dishes,and incubated at constant temperature 20,25,and 30℃,and alternating temperature 15-25,20-30,15-30,and 20-35℃under either an 8h photoperiod or total darkness for 28 consecutive days.Different methods were used to break the dormancy owing to hard seededness in this species such as chemical scarification by immersing in concentrated sulphuric acid for 5,10,15,20,25,30,45,and 60 min,in 0.2%KNO3 solution to saturate the seedbed,and prechilling for 7 d at 7℃and mechanical scarification by cutting.The results showed that alternating temperature at 20-30℃with 8 h photoperiod and 16 h darkness was optimum for G.uralensis seed germinating in the laboratory.Hard seeds were broken by concentrated sulphuric acid soaking or mechanical scarification by cutting.Germination of seeds harvested in two different years was both promoted by immersing for 30-45 min in concentrated sulphuric acid.KNO3 solution was ineffective for reducing hard seeds.During seed germinating,the first count was on the 7th day and the last count was on the 14th day.
文摘Wheat is a strategic crop for food security in Pakistan with predominance of smallholder farmers. Farmer-saved seed （FSS） is used nearly by 75% of farmers for wheat production. Frequent variety or seed replacement is uncommon even among large-scale farmers, and certified seed （CS） is mostly bought to verify the value of new varieties. Replacing old and obsolete varieties by new high yielding disease resistant varieties is key to transferring new genetic gains to farmers. For the first time in Pakistan, on-farm factorial experiments involving seven new and five old wheat varieties and their corresponding CS and FSS were conducted. A total of 49 farmers representing major wheat cropping patterns throughout the country participated in these trials in the 2014 and 2015 wheat growing seasons. Analysis of variance revealed that there was highly significant difference between wheat varieties and between seed classes. New variety ＋ CS gave 33.8% more grain yield as well as higher marginal return over farmers＇ variety ＋ FSS. Grain yield and returns from new variety ＋ FSS and farmers＇ variety ＋ CS were at par. Scientific knowledge generated in this research demonstrated that use of CS ＆new wheat varieties is best option, while growing new varieties with FSS is a second choice for the advantages accruing from their built-in genetic traits of economic importance over growing CS of old and obsolete varieties. Having more flexible seed system will help accelerate the delivery of new genetic gains to farmers＇ fields.
基金supported by the National Key Research and Development Program of China(2022YFD1601502 and 2023YFD1200202)the National Natural Science Foundation of China(32272167 and 32341028)+1 种基金the Sichuan Science and Technology Program,China(2022ZDZX0015)the Fundamental Research Funds for the Central Universities,China(SCU2019D013)。
文摘Brassica napus,one of the most important oil crops cultivated globally,is severely impacted by prolonged soil contamination with cadmium(Cd),resulting in decreased yields and poor seed quality.This crop exhibits a high adsorption capacity for Cd,making creating seed resources with low Cd accumulation an essential strategy to alleviate this challenge.To address this issue,we genetically edited BnaNRAMP1 in B.napus by targeting three different exon regions,resulting in new germplasm resources with significant differences in Cd accumulation capacity and unaffected yield.Among these,the mutant K140-22,specifically targeting the 7th exon,is distinguished by its substantially reduced Cd accumulation.Further,enzyme assays of the antioxidant defense system in both roots and shoots of K140-22 revealed its enhanced antioxidant activity,which contributes to elucidating the molecular mechanisms of plant tolerance to heavy metal stress.Remarkably,this mutant also maintained equivalent agronomic traits and seed quality,which highlights its potential as a germplasm resource for rapeseed breeding for low Cd accumulation and elevating rapeseed economic value in Cd-contaminated soil.
基金financially supported by USDA,Washington for conducting this study under the project"Studies on Himalayan Pines"(1996-2006)
文摘We analyzed 17 seed sources(seed stands)ofPinus wallichiana for variations present in cone and seed characters,scattered over natural distribution in north-west Himalayan states(Uttarakhand and Himachal Pradesh)of India.The significant variations were observed in cone weight,cone length,cone width,seed length,seed width,seed weight,seed germination,radicle length,and plumule length among different seed sources of the species.Significant positive correlation between seed weight,cone weight and cone width showed that seed weight in the species depend more on the cone size.Seed germination was also positively correlated with seed weight,cone weight and radicle length in the study.The estimates of variability with regard to genetic parameters for seed weight,seed germination,cone length,cone width,cone weight showed wide range of variation in the study.Seed weight showed high heritability values coupled with maximum genetic gain.Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i,e.genotypic and environmental interaction,The study suggests that the seed weight should be given the top priority for the further improvement of this species.
文摘To screen high-quality early-maturing rapeseed germplasm resources,this study took six early-maturing Brassica napus varieties(ZY1,ZY2,ZY3,ZY4,ZY5,and ZY6)as research objects to compare and analyze their agronomic traits,resistance,and yield traits.The results showed that the six early-maturing rapeseed varieties exhibited strong pre-winter growth,with the number of green leaf on the main stem ranging from 9.0 to 11.6,the total leaf number of main stem from 11.8 to 14.2,the maximum leaf length on main stem from 41.28 cm to 47.54 cm,the maximum leaf width from 12.02 cm to 13.38 cm,and the rhizome thickness from 20.64 mm to 25.82 mm.The order of green leaf,total leaf,maximum leaf length,and rhizome thickness from high to low across varieties was ZY1>ZY2>ZY3>ZY4>ZY5>ZY6,while the maximum leaf width followed ZY2>ZY1>ZY3>ZY4>ZY5>ZY6.Compared with other varieties,ZY1 and ZY2 had earlier bolting,initial flowering,final flowering,and harvesting times.The growth periods of the varieties were 183-189 d,with ZY1 being the shortest(183 d)and ZY2 following(185 d).Resistance investigations showed that ZY1 had the lowest freeze damage rate(13%)and freeze damage index(0.043),followed by ZY2(15%and 0.060).No Sclerotinia stem rot was observed at the seedling stage,while all varieties developed the disease at maturity;ZY1 had the lowest incidence(15%)and disease index(0.050),followed by ZY2(18%and 0.070).In terms of yield traits,the yield per plant of the six varieties ranged from 11.46 g to 14.53 g,with ZY1 being the highest(14.53 g)and ZY2 following(13.42 g).In conclusion,ZY1 and ZY2 exhibited vigorous pre-winter growth,early bolting and flowering,short growth periods,strong freeze and disease resistance,and high yield per plant,making them ideal materials for early-maturing rapeseed breeding.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201203052)the Fundamental Research Funds for the Central Universities(Nos.KYZ201402 and KYZ201202-9)the National Natural Science Foundation of China(No.31271806)
文摘Pre-harvest desiccation may increase the efficiency of seed production. Field studies were conducted to determine the effects of diquat, paraquat, and ethephon applications on grain moisture, grain weight, and seed ger- mination of hybrid rice Yanliangyou 88 （Oryza sativa ssp. indica） and conventional rice Wuyunjing 7 （Oryza sativa ssp. japonica）. In 2013, we tested 12 treatments applied at four weeks （Yanliangyou 88） and six weeks （Wuyunjing 7） after heading. Results showed that reductions in moisture content were significant two and four days after chemical ap- plication. Chemical applications had no adverse effects on lO00-grain weight, germination percentage, or germination index, but there were negative effects on the percentage of normal seedlings. Desiccation effects increased with increase in the period after application, while the effect of ethephon combined with diquat or paraquat on desiccation was limited compared with that of diquat or paraquat alone in a short period after application. In 2013, chemical ap- plications reduced the moisture content by from 0.5% to 6.4%, the germination percentage by from 0% to 3.3%, and the percentage of normal seedlings by from 13.3% to 100.0%. Among the treatments, diquat applied at 120 g/ha resulted in effective desiccation with fewer negative effects on grain weight and seed germination in 2013 and 2014. Therefore, diquat may have potential as a pre-harvest chemical desiccation treatment for rice. These results may provide a basis for developing and implementing protocols for large scale field trials.
基金supported by grants from the National Natural Science Foundation of China(32121003,32325038)Key Research and Development Projects of Sichuan(2021YFYZ0016)Open Project Program(SKL-ZD202207)of State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China。
文摘Rice(Oryza sativa L.),a thermophilic crop,is highly sensitive to cold stress,particularly during the seedling stage.Developing cold-tolerant rice varieties is a possible strategy to mitigate yield losses caused by low temperatures.However,few genes for cold tolerance have been identified.In this study,we identified OsALA4(Aminophospholipid ATPase 4),encoding a plasma membrane-localized P4-ATPase,from a chromosomal segment substitution line(CSSL-K2832-2)harboring cold-tolerance QTL qLTS5(Low Temperature Sensitive 5).Genetic and subcellular localization analyses revealed that OsALA4 regulates cold tolerance by maintaining plasma membrane fluidity and cellular homeostasis.Physiological assessments showed that OsALA4 reduces malondialdehyde(MDA),electrolyte leakage,reactive oxygen species(ROS),and cell death under cold stress.Promoter activity assays indicated that stronger OsALA4 expression in Nipponbare(OsALA4Nip)correlated with enhanced cold tolerance.Further experiments demonstrated that SNP sites within the promoter regions(-1500 bp to-700 bp)of OsALA4Nipand OsALA49311influenced their activity.This study highlights Os ALA4 as a valuable genetic target for breeding cold tolerant rice.
基金supported by the Ethiopian Institute of Agricultural Research Organization
文摘Juniperus procera Endl. is economically important timber species, but its populations are extremely small and fragmented in its natural habitat, thus, calling for immediate ex situ conservation. Here we examined the effects of seed sources and storage temperature on the longevity of Juniperus procera seed lots through collection and preservation of seeds in seed banks. Seeds were collected from nine sites across the species natural distribution in Ethiopia and stored in four warehouses： modern cold room （5℃）, mud house （15℃）, concrete block house （17℃ or corrugated iron house （20℃） for 42 months. Every three months, a random sample of stored seeds were drawn and tested for germination. A highly significant variation （p 0.01） in germination of stored seeds was observed among different storage environments, seed lots, and duration of storage. Over the storage period, seeds stored in the cold room had the highest mean percentage germination, followed by the mud house, corrugated house and blocket house. The cold room （41%） and the mud house （38%） maintained the same level of germination as the intitial germination of the seedlotds （42%）. The variation in longevity of stored seeds was significnatly correlated with the initial germination of seed lots （r 0.80; p 0.01）. Cold storage also resulted in enhancement of germination through its stratification effect that terminated the non-deepphysiological dormancy of juniper seeds. In conclusion, seed lots with good initial germination can be effectively stored in cold room （5℃） up to four years. In the absence of modern cold stores, mud houses can be used as a good alternative to store seeds at local level.
基金financed by the Ministry of Higher Education and Scientific Research of Côte d’Ivoirethe French Development Agency and IRD (Institut de Recherche pour le Developpement) in the framework of PRESeD-CI 2 (Renewed Partnership for Research for Development in Côte d’Ivoire)C2D (Debt Reduction Contract) of the AMRUGECI project (Support for the Modernization and Reform of Universities and Grandes Ecoles of Côte d’Ivoire)
文摘Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforestation programmes for endangered species like Pterocarpus erinaceus. In the present study, to assess seedling germination and vigour in P. erinaceus as a function of seed size in two environments, 1080 seeds and 360 seedlings were evaluated at two separate sites in Côte d'Ivoire. The results show that large seeds had very high germination rates (up to 100%) and produced more vigorous plants better able to adapt to climate change. The maternal environment and seed size had a significant influence on seed germination (P < 0.05) and seedling development (P < 0.05) and biomass (P < 0.05). Seedlings were most successful at the site with a humid tropical climate (Daloa). Seedling leaves had the same resistance regardless of seed size and study site, but leaf moisture content was more stable in seedlings grown from medium and small seeds. These results will help guide conservation strategies for the species and are key factors for rural populations, loggers, and forest management structures for the silviculture of this species.
文摘Information on seed vigor of the vegetable crops is always important and necessary due to the increasing demand of high quality seeds for sowing and high-value commercial. The cultivation of these species, conducted intensively, should be established with seed high potential physiological and health for the development of a more productive and sustainable agriculture. The present study was conducted to evaluate the potential physiological of seed lots of radish and coriander. The experiment was conducted at the laboratory of seed analysis and greenhouse of the plant science department of the Federal University of Pelotas in South Brazil. Four radish seed lots, cultivar ＂Saxa＂, and four coriander seed lots, cultivar ＂Verdito＂ were used. Germination seed test, first count of germination, accelerated aging test, electrical conductivity and seedling emergence were used to evaluate the physiological quality of the lots. The experimental design was completely randomized design with five replications. Means were compared by Tukey test. The accelerated aging test was the most efficient test in assessing the physiological quality for both lots of radish seeds and coriander and this test provide coherent results with seedlings emergence.
基金Project supported by the Major Science and Technology Special Project (priority subject) of Zhejiang Province (No. 2008C12005-1)the Key Project of Education Department of Zhejiang Province (No. 20070147), China
文摘Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.
文摘Seed vigor is a more promising seed quality character reflecting potential seed germination, field emergence and seed storage ability under different conditions than standard germination. Standard germination is influenced by genetic background and environmental effects during seed development and storage conditions. The latest research on physiological mechanism in seed vigor showed that at the late stage of seed development, the development of seed vigor involves some stress-resistant substances including late embryogenesis abundant （LEA） protein, oligosaccharides and abscisic acid （ABA）. Whereas the loss of seed vigor, or seed aging and deterioration, could be attributed to lipid peroxidation, chromosome deformation and genes aberrance, and embryo protein degradation, etc. Seed vigor is a quantitative character controlled by multi-genes. Genetic and quantitative trait locus （QTL） analyses on seed-vigor trait in model plants, such as Arabidopsis and rice, are mostly concentrated on related morphology traits, whereas few physiological traits have been researched. It was concluded that, all of the QTL genetic characteristics of seed vigorincluding QTL quantities, its locus on chromosome, genetic effects, and interaction effects between genetic and environment, differed with plant species and used seed-vigor traits.
基金This work was supported by grants from the National Natural Science Foundation of China(31900229 to Q.H.and 31922014 to W.Q.).
文摘As a multicellular organism,rice flourishes relying on gene expression diversity among cells of various functions.However,cellular-resolution transcriptome features are yet to be fully recognized,let alone cell-specific transcriptional responses to environmental stimuli.In this study,we apply single-cell RNA sequencing to both shoot and root of rice seedlings growing in Kimura B nutrient solution or exposed to various abiotic stresses and characterize transcriptomes for a total of 237,431 individual cells.We identify 15 and 9 cell types in the leaf and root,respectively,and observe that common transcriptome features are often shared between leaves and roots in the same tissue layer,except for endodermis or epidermis.Abiotic stress stimuli alter gene expression largely in a cell type-specific manner,but for a given cell type,different stresses often trigger transcriptional regulation of roughly the same set of genes.Besides,we detect proportional changes in cell populations in response to abiotic stress and investigate the underlying molecular mechanisms through single-cell reconstruction of the developmental trajectory.Collectively,our study represents a benchmark-setting data resource of single-cell transcriptome atlas for rice seedlings and an illustration of exploiting such resources to drive discoveries in plant biology.
