Abstract:Tea［Camellia sinensis （L.） O.Kuntze］germplasms are strategic resources ensuring the high quality development of tea industry， and raw materials enabling the original innovation in tea science and technology， breeding and development of new products with special characteristics.Studies on tea germplasms are of great value and significance considering the relevance on the innovation and sustainability of tea seed industry.Yunnan lies in the Southwest China，the long history of tea growing and the unique climate and geographical conditions of low latitude plateau have bred rich tea germplasm resources， a large number of wild and cultivated ancient tea plants are extensively distributed in Yunnan province， which is the origin center of tea plant in the world and the province with the largest species， quantity and distribution of tea group plant，after 60 years of research， with the hard work of scientific and technological workers and the active support of relevant departments， Yunnan tea germplasm resources have achieved fruitful results in the investigation and collection， conservation and cataloguing， identification and evaluation， and innovative utilization， and a series of significant progress has been made.This paper systematically expouned the main progress and existing problems of Yunnan tea germplasm resources research in the past 60 years，meanwhile，the future development direction of tea germplasm resources was discussed and prospected， which provided a reference for the research on tea germplasm resources.

Abstract:Hazelnut （Corylus） is one of the important nut crops and woody oil species with highly nutritional values. The genus Corylus is a member of the birch family （Betulaceae） in the order Fagales， and includes 13 species identified to date around the world. The European hazelnut （C. avellana L.） is the species with commercial cultivation in the European countries and the west states of the United States. The earliest European hazelnut breeding appeared in the 1900s and the major modern breeding programs started in the United States in 1960's. After several decades of variety selection， many varieties were released with excellent characteristics， such as the varieties with highly stress resistance for the in-shell and the kernel markets， pollination varieties and ornamental varieties. In China， the first generation of hazelnut hybrid breeding performed in 1980's， a total of 15 cultivars have been released and widely cultivated in twenty-odd provinces of China from dozens of candidate seedlings since 2000. The planting area is about 112，000 hm² in China at present. The new generation hybrid breeding has been ongoing since 2006. New breeding projects and regional trials are mainly aiming to select cultivars with cold hardiness， branch shriveling resistance， drought resistance， heat resistance， and pollination varieties. Up to now， cross breeding is still a main method in hazelnut breeding. Therefore， to continuously introduce and efficiently utilize the special germplasm resources of European hazelnuts is an effective way to speed up the breeding work of hazelnut in China. Based on a large number of domestic and foreign literatures， the cultivation status of European hazelnuts， the traits of C. avellana L. and their narrow-sense heritabilities， main targeted traits of European hazelnut varieties for kernel market and their evaluating standard， as well as the main characteristics of new advanced varieties released in the United States， Italy， Spain and Turkey were listed in the review. Thus， the precious nut trees， European hazelnuts， can be comprehensively illustrated to the domestic readers and researchers. Also in this review， the introduction history， scientific research， germplasm collection and protection， as well as the cross breeding utilization of European hazelnuts in China were summarized at the same time. Meanwhile， the problems in the introduction， regional trials and cross breeding utilization of European hazelnuts in China were discussed. Aiming to the problems above， constructive suggestions were proposed in terms of sustainable introduction， germplasm protection， cross breeding utilization， research communication and the funding application. Finally， the prospective of scientific research and industry development in China was summarized at the end of this review. The authors sincerely hope this review could provide some references in hazelnut breeding research and cultivation promotion in China.

Abstract:Anthocyanins， which are natural pigments and serve as important natural antioxidants scavenging free radicals， are rich in a variety of compounds that are important in health care. Anthocyanins affect the ripening， taste and color of fruits and vegetables， and prevent plants from abiotic and biotic stresses. Therefore， optimizing anthocyanin content is regarded as the breeding goal in many horticultural crops. As the secondary ethylene signaling transcription factors， ethylene response factors （ERFs） respond to plant hormone signaling and can result in feedback regulation， and these genes are known to modulate the process of ethylene regulating anthocyanin biosynthesis via various mechanisms. In terms of the molecular mode， ERFs in regulation of anthocyanin biosynthesis rely on the physical interaction with transcription factors， activating transcription factors， forming regulatory complexes with MBW or directly activating structural gene promoters. This study aims to provide a theoretical basis for further elucidating the mechanism of ERF regulating anthocyanin biosynthesis， and to explore the relationship between the rapid accumulation of anthocyanins and the increase of ethylene release in fruits and vegetables at the late ripening stage.

Abstract:The genetic diversity analysis of 135 rice germplasm resources collected from different altitudes in Yunnan province， P.R. China， were genotyped by using the gene chip GSR40K. The rice germplasm resources at different altitudes were found with rich genetic diversity， and they were divided into five subgroups： indica， partial indica， intermediate， japonica and partial japonica. Eighty-two genes with expected breeding value were genotyped by haplotype markers and functional markers. All accessions were found with the genes related to the grain shattering. Nearly 70% of rice varieties were detected with rice blast resistant genes， whereas only a small proportion of accessions containing insect resistance and fragrance genes were identified. The accessions in this collection were divided into seven subgroups by cluster analysis and principal component analysis. The differentiation of each marker site among the 7 subgroups was evaluated by the G_st value of genetic differentiation index， indicating that there was high genetic differentiation among the 7 subgroups. Moreover， at least 0.09% of the genomic segments in this collection are completely different， and only 0.08% are frequently communicated and fixed， suggesting an extremely low frequency of gene exchange between different subpopulations. Based on the difference of altitude among subpopulations， the differential genomic regions among populations were proposed associating with altitude adaptability. Collectively， these results provided scientific basis for effective protection and efficient utilization of rice resources in rice breeding.

Abstract:Rice landraces harbour many elite genes modulating important agronomic traits， and are important resources in rice genetic improvement. In this study， 47 pairs of SSR markers and 16 phenotypic traits were deployed to conduct the genetic diversity and clustering analysis of 58 excellent rice landraces. The results showed that 284 polymorphic alleles were amplified from 58 rice landraces with an average of 6.04 polymorphic sites （variations： 3 to 10）； the polymorphism information content （PIC） ranged from 0.38 to 0.81 with an average of 0.67； and the genetic diversity index （GDI） ranged from 0.76 to 1.88 with an average of 1.36. These suggested that these SSR markers revealed rich polymorphisms and were able to clarity these rice landraces. The variations on 16 phenotypic traits of this collection were largely different； the variation coefficients of awn length， flag leaf angle and filled grains per panicle were 2.15， 0.73 and 0.51， respectively； those of panicle length， growth period， thousand-grain weight and flag leaf width were below 0.2. The clustering analysis showed that the dendrogram of this collection based on either markers or phenotypic traits were generally consistent. In some lines sharing pedigree （Erjiunan 1， Guangluai 4， Lucaihao， Aijiaonant， Jinnante， Guangluai 15）， or sister lines （between Hanmadao 1 and Hanmadao 2， Meihuanuo 1 and Meihuanuo 2， Muguanuo 1 and Muguanuo 2， Xiangnuo 1 and Xiangnuo 2）， they were clustered together using either of both datasets. Collectively， gained from evaluating the genetic diversity of different rice landraces， this study provided insights in selection of elite parental lines applicable in rice breeding.

Abstract:Nangeng 46 is a high-quality japonica rice variety developed by Jiangsu Academy of Agricultural Sciences and this variety shows good eating quality， resistance to stripe disease， and high yield. This study investigated a series of rice varieties derived from Nangeng 46 regarding to agronomic traits including yield， quality and disease resistance. Their allelotypes of important functional genes were genotyped based on single nucleotide polymorphism （SNP） markers. As the first good eating quality japonica variety in the middle and downstream valley of the Yangtze River， Nangeng 46， which serves as the parental line in the breeding programs， supported the development of 29 varieties in provinces Shanghai， Anhui， Hubei， Jiangsu， Liaoning， and Hebei， by 2022. The obvious variations on the appearance quality， physicochemical characteristics of grain and starch viscosity characteristics were observed among the offspring varieties， while the variations on the growth period， plant height， yield and processing quality were rather minor. The allelic analysis of important functional genes showed that Wx was the main gene affecting the taste of derived varieties rice. Along with the increase in the number of quality genes with different alleles from Nangeng 46， the taste quality gradually decreased. In the future， the breeding programs using Nangeng 46 as the parent， we would like to suggest the selection with attention on appearance quality， grain physicochemical characteristics and starch viscosity characteristics. In addition， the deployment and complementarity of blast resistance genes should draw an attention in the future.

Abstract:In order to dissect elite waxy maize germplasm resources from landraces in maize breeding， the genetic diversity 207 Guangxi waxy maize landraces and 6 reference waxy inbred lines was analyzed by genome-wide scanning based on 10K SNP markers. The results showed that the overall genetic diversity of this population was relatively high， with an average expected heterozygosity （He） of 0.31， observed heterozygosity （Ho） of 0.23， and an average polymorphic information content （PIC） of 0.25. The genetic diversity in central Guangxi was the highest （He=0.32， Ho=0.24， MAF=0.24， PIC=0.26） at the population level. These landraces were divided into four major groups by population structure analysis. A correlation on the genetic relationship between populations and the geographical originations of landraces was not observed. In general， the genetic similarity coefficient among Guangxi waxy maize landraces is low， thus suggesting abundant the genetic diversity. Analysis of variance for molecular variation （AMOVA） showed that 99% of the genetic variation is contributed by the intra-population diversity. The genetic differentiation coefficient （F_ST） between groups was 0.008，indicating a low-level differentiation among groups. In summary， the present study unlocked the genetic diversity and relationship of waxy maize landraces in different regions of Guangxi， and provided a theoretical guidance for waxy maize germplasm improvement and breeding of new varieties in Guangxi.

Abstract:Coordinating with the Third National Survey and Collection Action on Crop Germplasm Resources， we collected 110 peanut landraces in Guangdong province， P.R. China. Fourteen phenotypic traits in the collection were recorded， followed by diversity analysis， correlation analysis， principal component analysis and cluster analysis. The results showed that the coefficient of variation at 14 phenotypic traits ranged from 5.18% （crude fat content） to 37.34% （pod number per plant）. By correlation analysis， the pod number per plant was significantly negatively correlated with main stem height， and extremely significantly positively correlated with branch number. Fourteen phenotypic traits were classified into six principal components by principal component analysis， with a cumulative contribution rate of 71.074%， which can represent a large proportion of the phenotypic variation. 110 peanut landraces were divided into four groups by cluster analysis when applying the euclidean distance of 15， which had the characteristics of high crude fat， high linoleic acid， high yield， high resistance to rust and leaf spot respectively. This study provides a reference for the utilization of newly collected peanut germplasm resources.

Abstract:Paphiopedilum species are known as unique flower shape， gorgeous color， long ornamental period and have great ornamental and economic value. The classification of the genus is controversial. The diversity and correlation analysis of 27 phenotypic traits were carried out by investigating 29 species of Paphiopedilum， and cluster analysis was carried out based on the principal components of phenotypic traits. The results showed that the phenotypic traits of Paphiopedilum were rich in diversity. The variation range of genetic diversity index （H′） of 17 quantitative characters was 0.7834-2.0318. Among them， the strong variation characters with genetic diversity index greater than 2.0 were flower length and flower width， the weak variation character with genetic diversity index less than 1.0 was flower number， and the variation range of genetic diversity index of 10 quality characters was 0.5098-1.1241. The diversity indexes of petal shape and Lip main color were the highest， both exceeding 1.0， and the smallest were staminode bottom concave and anther type，from the results of diversity analysis， it can be seen that 29 species of Paphiopedilum have large differences in phenotypic traits among species， with rich diversity. The coefficients of variation （CV） of 17 quantitative traits ranged 18.22%-59.09%， the petal length/petal width and peduncle length exceeded 50%， the results showed that the interspecific phenotypic characters of Paphiopedilum palustratum were dispersed greatly.Correlation analysis showed that the phenotypic characters of Paphiopedilum were closely related and complex. Five principal components with eigenvalues greater than 1 were selected by principal component analysis， and the cumulative contribution rate was 84.176%， which could reflect most of the information of the phenotypic characters of Paphiopedilum， and the characters and indexes of flower organs had a great impact on the phenotypic diversity. Cluster analysis showed that 29 species of Paphiopedilum were divided into 6 groups， which was similar to other classification methods， but there were also some differences.

Abstract:Clivia （Kaffir lily）， which belongs to the genus Clivia of the family Amaryllidaceae and natively distributes in South Africa， is considered as one of the most famous evergreen ornamental plants in the world. Several new species of the genus Clivia， and a new natural hybrid， Clivia×nimbicola， have been discovered in recent years. Up to date， six Clivia species and three varieties have been recognized. China is one of the largest countries for clivia production in the world， whereas only few studies have been carried out in China. The taxonomy of Clivia species and cultivars is often confused or with mistake. Several clivia cultivars are commercially available in market， but they are yet reported in academic journals. This review introduced the phenotypic characteristics of Clivia species， varieties， cultivars and types， and generated the dichotomous key that enables to clarity several confusing species. Based on the marketing and scientific research in China， ten series of the commercial clivia cultivars are suggested. We provide the prospective on the germplasm resources innovation， floral breeding， in vitro propagation and molecular breeding in clivia， which would have implication in clivia marketing and these academic research.

Abstract:In order to clarify the situation of the quality-related genes and corresponding traits of Chinese wheat varieties， 530 wheat varieties released in China in the recent years were analyzed for volume weight， crude protein content， wet gluten content， water absorption and stability time. This collection was genotyped with 13 quality related KASP markers， enabling deciphering the distribution and pyramiding of favorable alleles in wheat-planting areas. The frequency of favorable alleles among different regions was unevenly distributed. The frequencies of 1BL/1RS （-）， 1Ax 1/1Ax 2*， Pinb-D1b and Pinb-B2b were significantly different among different regions， while no difference on the frequency of 1Bx17+1By18， TaPsy-D1a and TaPod-A1b among different regions was observed. Twelve genotypes containing four elite alleles of 1B/1R （-）， 1Ax 1/1Ax 2*， 1Dx5+1Dy10 and glu-B3g+ at five gluten quality related loci were identified. For three grain hardness genes， the elite alleles combination （Pina-D1b + Pinb-D1b + Pinb-B2b） was not detected， while the combinations of either Pina-D1b + Pinb-B2b or Pinb-D1b + Pinb-B2b were found in 16 and 88 samples， respectively. Ten samples were found containing favorable allelic variants of five color related genes. Four genotypes simultaneously containing 10 favorable alleles were obtained， and 16 varieties with 9 favorable allelic variants were found. The results of quality analysis showed that there were regional differences in quality traits， and the stability time was inconsistent with protein content and wet gluten content. The frequency of elite alleles at gluten quality related genes， such as 1BL/1RS （-）， 1Ax1/1Ax2* and 1Dx5+1Dy10， was significantly different in the wheat varieties with strong gluten， medium strong gluten and medium gluten， and the allele frequency was positively correlated with the quality.

Abstract:In order to systematically understand the current status on the character diversity of wheat varieties from different origins （southern part and northern part） in Huang-Huai winter wheat region， 109 newly-released varieties from this region were investigated in this study. The character diversity analysis and comprehensive evaluation based on 12 agronomic and quality traits were carried out by using Shannon-Wiener diversity index （H′?）， cluster analysis， principal component analysis， regression model construction， etc. 84 and 25 varieties were collected from the southern and northern part of Huang-Huai winter wheat region， accounting for 77.1% and 22.9%， respectively. The wheat varieties showing strong gluten and medium strong gluten accounted for 11.9% and 16.5% respectively， accounting for 28.4% in total. The variation coefficient on 12 traits ranged from 1.66% to 76.64%， with an average of 11.37%. The variation coefficient of stabilization time was the largest， and the variation coefficient of bulk density was the smallest. The H′ index on 12 traits ranged from 1.50 to 4.65， with an average of 3.78. The H′ index on basic seedling was the smallest （1.50）， and the rest H′ were above 3.00. The H′ on 12 traits of wheat in the northern part was higher than that in the southern part， with an increase of 24.7%-188.6%. The increase of growth period was the smallest， and the increase of basic seedling was the largest. At the square Euclidean distance of 10.0， 109 wheat varieties were grouped into six categories， mostly being coincidence with their origins. There were significant or extremely significant differences in bulk density， growth period， spike number and water absorption rate of wheat varieties from different origins， part which were 0.9%， 3.5%， 11.0% and 4.1% lower in the southern than that in the northern， respectively. The cumulative contribution rates of the first six principal components of wheat varieties from different origins had little difference， with 80.25% in the southern part and 83.33% in the northern part. The comprehensive scores of wheat varieties from different origins were strong gluten wheat > medium strong gluten and medium gluten wheat. The richness and uniformity of wheat traits in the northern part were higher than those in the southern part， and the evolutionary potential was higher. The five traits of spike number， grain number per spike， bulk density， protein content and water absorption rate could be used to evaluate the comprehensive performance of northern part wheat varieties. Gained from these results， it is suggested that future improvement of wheat varieties in the southern part would profile from enlarging the genetic basis. The six traits including growth period， spike number， yield， bulk density， protein content and wet gluten content could be used to evaluate the comprehensive performance of wheat varieties in this region.

Abstract:Wheat variety Yannong 999 （YN999） shows stably high yield potential with strong environment adaptability. Unlocking its genetic basis and key chromosomal regions underlying high yield performance will provide theoretical support for the further application. In this study， a 55K wheat SNP array was used for genotyping the YN999， its 46 derived varieties （lines） and a natural mapping population containing 243 wheat varieties （lines）. The genetic effects of the key chromosomal segments undergone strong selection was elucidated. The genetic cause of high-yielding potential in YN999 was dissected based on the composition of excellent alleles underlying the three yield components. The characteristics of high thousand kernel weight were preferentially selected and present in the derived varieties （lines）. Genotyping using the wheat 55K SNP array revealed that the average genetic similarity coefficient of YN999 if compared to 46 derived varieties （lines） was 0.87. The genetic contribution of YN999 to its derived varieties （lines） of F₃， F₅， F₆ and F₇ were 84.94%， 86.19%， 86.67% and 87.65%， respectively. A total of 222 segments of YN999 with over 95% transmission rate were detected in the offspring of YN999， and the length of the segment varied from 5.04 Mb to 108.75 Mb， among which 2A contained the longest segment with high frequency selection， being 483.37 Mb， and 7D contained the shortest of 13.84 Mb. A total of 135 identified QTL related to yield traits were coincided with the 222 high-frequency selection regions， with 80， 48 and 7 QTL in the A， B and D genome， respectively. A total of 1195， 267， 790 and 678 significant SNPs， which were correlated with yield per plant， kernel number per spike， 1000-grain weight and spike number per plant， respectively， were detected by single marker QTL analysis using a natural mapping population. Among those， approximately 84.02%， 51.69%， 94.18% and 13.42% alleles contributing to the higher yield performance were identified from YN999. These results indicate that YN999 has enriched the superior alleles of yield per plant and 1000-grain weight， which might be the important genetic basis for the high and stable yield in YN999. This study provided theoretical reference in application of YN999 as key parent in molecular breeding programs， and identification and cloning of the genes with high yield performance.

Abstract:The high molecular weight glutenin subunits （HMW-GS） compositions and the quality parameters in 184 Sichuan wheat varieties （released from 1949 to 2018）， one introduced variety and two landraces were analyzed. The results showed that there were three alleles at Glu-1A including 1， N， 2*， eight at Glu-1B including 7， 20， 22， 7+8， 7+9， 6+8， 14+15 and 23+18， and three at Glu-1D including 5+10， 2+12 and 3.1^t+11*^t. These subunits on sub-genomes A， B， D formed 23 allele combinations， and the combination （N/7+9/5+10） was found with a frequency of 12.3%. Taking advantage of breeding effects， the allele diversity at the Glu-1 locus， as well as the ratio of high-quality strong gluten 1 （Glu-1A） and 5+10 （Glu-1D） were gradually increased. The medium-weak gluten wheat varieties were found with predominant proportion in Sichuan province. The increase on test weight and sedimentation value， but the increase followed by decreased on other quality traits were observed. This study can provide reference for further improvement of wheat quality in Sichuan province， China.

Abstract:Based on the red-flesh color peaches showing different intensities， this study attempted to decipher their formation mechanism in order to provide theoretical basis for efficient breeding of red peach varieties. The promoter activity of PpMYB10.1 was detected via GUS staining， and the candidate transcription repressors binding on its promoter were captured through DNA-pull down assay. The function of these candidate genes were determined by double luciferase and yeast two-hybrid assay. The results showed that： （1） The expression of PpMYB10.1 and anthocyanin content in flesh peaches with deep-red， red and light-red were gradually decreasing. （2） Activity of PpMYB10.1 promoter with a 483 bp deletion was weaker than that without the sequence. （3） Interestingly， we identified a candidate transcription repressor Prupe.2G302800 based on the 483bp deletion. The protein strongly interacted with PpBL， a major factor in anthocyanin synthesis and resulted in a reduction on the transcription of PpMYB10.1. Prupe.2G302800 is unlikely the direct factor modulating the red flesh of peach， whereas it might play an important role in decreasing red-flesh color by inhabiting PpBL transcription activity.

Abstract:The experiment aimed to explore the genetic variation at traits of sugar and acid components in F₁ generation of the jujube hybrid， which might offer further support for selecting the parents and quality germplasm selection in breeding. The contents of sugar and acid components in fruit of the 140 hybrid plants of JMS2 × Jiaocheng 5 and both parents were determined by high performance liquid chromatography （HPLC）. The results showed that the sugars in fruit of the hybrid progenies were mainly composed of sucrose， fructose and glucose， of which sucrose accounted for 52.5%. The variation coefficient of sugar components ranged from 26.74% to 35.45%， with the highest variation coefficient of glucose and the lowest variation coefficient of sucrose. The average value of fructose and glucose in F₁ plants were higher than the median value of both parents， while sucrose was lower than the median value. The main acids were malic acid， quinic acid and citric acid， of which malic acid accounted for 35.10%. The coefficient of variation of acid components ranged from 29.67% to 42.86%. The mean value of malic acid in F₁ was lower than the median value of both parents， and the mean value of oxalic acid and fumaric acid was higher than the median value. The other acid components were largely environment-dependent. Both sugar and acid components showed normal distribution characteristics and were quantitative characters controlled by multiple genes. Finally， the optimal hybrid lines J17 and J70 with higher sugar content were identified.

Abstract:Soybean is rich in nutrients and active substances. Oligosaccharides are beneficial functional components for human health， and identification of soybean oligosaccharide specific germplasms is of great practical significance. In this study， the content of oligosaccharides， including sucrose， raffinose， stachyose and total oligosaccharide， were quantified by high performance liquid chromatography （HPLC） method in a population of 264 soybean genotypes that were cultivated at two environments. It was shown that among the three oligosaccharides， sucrose accounts for the highest proportion of total oligosaccharides， and raffinose accounts for the lowest proportion. The total oligosaccharide content in Sanya city of Hainan province and Nanjing city of Jiangsu province ranged from 6.18%-11.46% and 4.19%-13.80%， respectively. Ten oligosaccharide specific genotypes with stable performance at different environments were obtained. Genome-wide association study（GWAS） was carried out by combining phenotypic and genotypic data of oligosaccharide content in natural soybean population. SNPs significantly associated with oligosaccharides content were identified and candidate genes were considered to be related with oligosaccharide/sucrose. Collectively， this study provided germplasm resources applicable for the selection and breeding of special soybean varieties， and also provided foundation for further exploring oligosaccharide candidate genes and developing their molecular markers in soybean.

Abstract:Seed coat color is an important agronomic trait that associates with crop domestication and serves as morphological marker. In mung bean， the seed coat color was related to the content of flavonoids. Cloning and application of seed coat color-related genes becomes of interest in development of new mung bean varieties with improved nutritional properties. In this study， the varieties 'Jilv 9' （black seed coat） and 'Ziyuan 330' （yellow seed coat） were used as parents to generate an F₂ segregating population. The BSA-seq approach was applied for mapping of the genes underlying the seed coat color. The association analysis using integrated SNPs and InDels suggested an interval of 3.26 Mb harboring 324 predicted genes， of which 49 genes were found with non-synonymous mutation and 15 genes were detected with frameshift mutation. By further use of 11 high-quality KASP markers in fine mapping， the candidate interval was finally delimited between KA330 and KA421 in the physical interval of 16，302，330-18，013，421 bp （1.71 Mb） on chromosome 4. The transcriptome data analysis and qRT-PCR expression analysis suggested six differently-expressed candidate genes， of which the LOC106758748 was annotated as a transcription factor MYB90 that was reported with a function in the flavonoid biosynthesis and served as key candidate gene regulating the seed coat color in mung bean. The results of this study can provide a theoretical basis for the cloning and utilization of the genes related to seed coat color in mung bean seed breeding.

Abstract:Heterosis utilization is one of the effective ways to significantly increase crop yield， in which the creation and utilization of sterile lines plays a vital role in the breeding and production of crop hybrids. In contrast to the traditional hybrid breeding technology， the third generation crop hybrid breeding technology based on the nuclear male sterility gene has layers of advantages such as safety on seed production， flexibility on bi-parental combinations， and stability on hybrid fertility. This technology has been widely used in maize， rice and other crops， and provides a possibility in future use of soybean heterosis. We previously mapped by positional cloning approach a nucleic male sterility gene MS6 that encodes an R2R3-MYB transcription factor in soybean. In this study， we deployed CRISPR/Cas9 gene editing technology to design two gene editing targets to knock out the MS6 gene in soybean variety Williams82. The transgenic plants carrying edited MS6 alleles were subjected for phenotype observation， pollen and fertility identification， thus approving the function of this gene in regulating soybean pollen formation and male fertility. A new ms6 germplasm showing stable male sterility was obtained in soybean. This provides theoretical and technical support for further establishing the third generation soybean hybrid breeding technology system based on MS6 gene and realizing the efficient creation of strong heterosis hybrids.

Abstract:The tiller angle is one of the most important traits in the plant architecture of rice， which significantly determines the rice yield. At present， the major tiller angle genes in rice are TAC1 （Tiller Angle Control 1） and TIG1 （Tiller Inclided Growth 1）. It is necessary to further explore new loci and molecular markers to promote ideal plant architecture breeding in rice. In this study， a BC₃F₂ population was developed using large-angled wild rice as the donor and small-angled cultivar Zhenshan 97 as the recipient， and tiller angle separation was observed in the 54th line. QTL mapping of tiller angel was performed using QTL-seq， and a QTL was detected on chromosome 8. TIG1 was identified as the candidate gene through sequence comparison of known genes within the interval. A KASP functional molecular marker was designed based on the causal variation of C?T at -449 bp in the promoter of TIG1. The marker was verified in the mapping population and varieties， and it was confirmed that the KASP marker can accurately identify the genotype of the TIG1 locus. In Geng/Japonica TIG1 with large angle is dominant， while 61.40% and 38.40% of Xian/Indica varieties carry tig1 with small angle and TIG1 with large angle， respectively. This marker has significant potential utilization value for improvement of rice plant architecture. The development of this KASP marker provides a new tool for molecular marker-assisted improvement of rice tiller angle and is expected to speed up the breeding process for the ideal rice plant architecture.

Abstract:Potato （Solanum tuberosum L.） is the third most important food crop in Yunnan province， China. Late blight has always been a devastating disease in potato production. Use of resistant varieties is the most fundamental and effective way to control the disease. In this study， screening of broad-spectra Rpi genes using molecular markers and evaluation of late blight resistance upon field inoculation were conduced in 255 potato genotypes. The results showed that 69， 53， 51， 12， 23 and 75 varieties （lines） were detected with resistance genes R8， RB， Rpi-blb2， Rpi-sto1， Rpi-sto1 and Rpi-vnt1.1， respectively. Eighty-one of the varieties （lines） were found stacking multiple Rpi genes， and 77 of them were collected from CIP. Gained from field resistance tests， 67， 31， 67 and 90 varieties （lines） were observed with high resistance， medium resistance， medium sensitivity and high sensitivity， respectively. The domestic germplasm was found with lower resistance and rare cases on stacking multiple Rpi genes. The gene R8 largely contributed to the field resistance against late blight. R8 via stacking with other Rpi genes can improve the degree of resistance compliance and field resistance. This study demonstrated that R8 has a high degree of compatibility with field resistance to late blight and could be used for marker assisted selection， which has implication for the future popularization and application of new varieties （lines） and resistance breeding in Yunnan province.

Abstract:In this study， the morphology， physiology and transcriptome of different types of leaves were measured in adult trees of Silver Poplar， which provided a reference for revealing the maturation effect. The main results are listed： （1） The leaf morphology at long branches and short branches was significantly different， and the leaves in different parts overlap to a large extent. （2） The in different parts of leaves was significantly different， and the content of chlorophyll a and total chlorophyll in the lower leaves were significantly higher than those of the upper and middle parts. The SOD enzyme activity in the lower leaves was significantly higher than that in the upper and middle parts. The MDA content was manifested as the middle > upper > lower par；.The starch content in lower leaves was significantly lower than that in upper and middle leaves； The IAA content of the leaves in different parts increased with the decrease of height， and the ABA content was the middle > the upper part > the lower part； The IAA and IAA/ABA of leaves at the long branches were significantly larger than those of the short branches， and the ZR content showed an opposite trend. （3） The number of differentially significant genes between different parts of leaves was less than the number of differentially significant genes between different types of leaves based on transcriptome data screening. （4） GO and KEGG enrichment analysis of different genes in each comparison group showed that the genes significantly enriched in the photosynthetic pathway in the upper long branching leaves relative to the lower long branching leaves （SC-vs-XC） and in the upper short branching leaves relative to the lower short branching leaves （SD-vs-XD）， and gene annotation of two of these genes showed that both genes encoded PsbR proteins， and the gene expression was up-regulated in the lower leaves. The expression of these two genes was found to be up-regulated in the lower leaves， and the analysis of the growth hormone transduction process showed that the expression of the genes was up-regulated in the shorter leaves.

Abstract:As an important agronomic trait of pepper， fruit color directly affects the commercial value of pepper， and the analysis of its genetic mechanism can provide guidance for the improvement of pepper fruit appearance quality. In this study， the genome-wide association study （GWAS） was used to identify SNPs and candidate genes that significantly associated with the fruit color in pepper. By taking the natural population composed of 195 annual peppers， the fruit color including immature fruit color and mature fruit color were investigated in two calendar years （2020 and 2021）. Through the DNA sequencing and SNP variation detection， the high-quality SNPs filtrated by quality control were used for GWAS. The results showed that the phenotypes at pepper fruit color traits collected from the two calendar years were completely consistent， indicating the inheritance of the traits. The frequency distribution of green fruit color and bright red fruit color was the highest， up to 89.74% and 60.51%， respectively. GWAS analysis revealed eight SNPs associating with the pepper fruit color， these loci were distributed on four chromosomes 0， 1， 3 and 4. LD block analysis was performed on significant SNP sites and candidate genes were screened， enabling the annotation of 31 candidate genes. It includes several strong candidates including the respiratory burst oxidase homologous protein A （capana01g000138）， isoflavone 2' - hydroxylase-like （capana04g000616， capana04g000617， capana04g000618， capana04g000619， capana04g000620， capana04g000621 and capana04g000622） and F-box-like/WD repeat-containing protein TBL1Y-like （Capana04g000624）. These results will provide a reference for molecular assisted breeding of fruit color in pepper.

Abstract:Grain filling rate is an important and complex agronomic trait that directly affects rice yield and quality. Huaidao 5， a superior rice japonica variety， derived from the 7208 ×Wuyujing 3 cross， shows a high grain filling rate， whereas its functional mechanism remains unclear. A transcriptome analysis in Huaidao 5 and Wuyujing 3 was performed by harvesting 14-days-after-fertilization grains. Real time fluorescent quantitative PCR was used to analyze the transcripts of few candidate genes， and Sanger sequencing was applied to identify their polymorphisms between Huaidao 5 and Wuyujing 3. 3230 up-regulated and 1171 down-regulated genes were detected between Huaidao 5 and Wuyujing 3. Gene ontology analysis indicated that these differentially-expressed genes were primarily involved in starch and sucrose biosynthesis， photosynthesis， carbon assimilation， and hormone biosynthesis and signaling transduction pathway. If compared to Wuyujing 3， more genes involved in starch and sucrose biosynthesis were up-regulated in Huaidao 5. Sixty-three hormone-related differentially expressed genes were detected， of which 38 genes were involved in the auxin pathway， suggesting that auxin plays an important role in the rice grain filling process. Several identified grain-filling-rate-related genes （GFR1， OsPFP1， OsPHO1；2， OsSWEET13， OsCIN2） were significantly up-regulated in Huaidao 5. Moreover， Sanger sequencing showed that GFR1^Huaidao5 might be an excellent haplotype to control the grain filling rate.

Abstract:Transcriptome sequencing was performed on the daughter root of Aconitum carmichaelii （DR） to explore the underlying molecular mechanism regulating the root expansion. DR at three time points during the expansion stages， namely S1 （1 d）， S2 （31 d） and S3 （61 d）， were harvested for sequencing. The identified differentially expressed genes （DEGs） were validated by real-time quantitative polymerase chain reaction （qRT-PCR）. 73600 unigenes were obtained via de novo assembly， including 7555 DEGs that are differentially expressed by comparative transcriptome analysis. There were 2560， 2171 and 6320 DEGs in the three pair-wise comparison groups of S2/S1 （S2 with respect to S1）， S3/S2 （S3 with respect to S2）， S3/S1 （S3 with respect to S1）， respectively. KEGG enrichment analysis showed that DEGs were mainly involved in starch and sucrose metabolism， plant hormone signal transduction， plant-pathogen interaction and phenylpropane biosynthesis. The genes in starch biosynthesis pathway were up-regulated and these genes in lignin biosynthesis were down-regulated， which was considered as a sign in the root expansion. The genes related to auxin， abscisic acid， cytokinin and gibberellin were involved in regulating the process of enlargement. Through testing a subset of candidate genes in these pathways using qRT-PCR， a pattern similar to that revealed by transcriptome sequencing was revealed. This study is the first to explore the dynamic transcriptional changes in the process of DR enlargement， and excavate the related genes involved in the regulation of the enlargement process， which provides clues for further research on the molecular mechanism of DR.

Abstract:Leaf-color mutants are crucial germplasms for deciphering the mechanisms of pigment metabolism and chloroplast development. In this study， to uncover the mechanisms of temperature-sensitive albino phenotype in Brassica napus， the physiological assessment and transcriptome analysis were performed in two resynthesized B. napus inbred lines， the white-leaf line W7105 and its green-leaf sibling line G7097. Under low temperature in field conditions， in albino leaves of W7105， the chlorophyll and carotenoid content were dramatically decreased and chloroplast structure was abnormal. Compared with green leaves， albino leaves showed significantly lower net photosynthetic rate （Pn） and significantly higher intercellular CO₂ concentration （Ci）. Transcriptome analysis of leaves at three different developing stages was performed in G7097 and W7105 lines. After pairwise comparisons， a total of 1532 differentially expressed genes （DEGs） associated with leaf color phenotype were identified， including 540 and 992 genes that were up-regulated and down-regulated， respectively. GO and KEGG enrichment analysis showed that the up-regulated DEGs in albino leaves of W7105 were significantly enriched in proteasome， translation process， carbohydrate and energy metabolism pathways； while the down-regulated DEGs were significantly enriched in chloroplasts， photosynthesis and electron transport chain. Moreover， several DEGs in chlorophyll and carotenoid biosynthesis were significantly down-regulated in albino leaves， suggesting that chlorophyll and carotenoid metabolisms were also impaired. Collectively， these findings provide references for further delimiting the candidate genes and uncovering the molecular mechanisms of albino leaves in B. napus.

Abstract:F. cymosum， which is the most widely distributed buckwheat wild resource， represents high genetic diversity in wild population. Due to the environmental changes and human actions that result in the loss of F. cymosum wild resources， it is urgent to protect F. cymosum wild resources. In this study， based on the collected F. cymosum wild resources， we compared the differences between sexual reproduction and asexual reproduction on the off-site reproduction of F. cymosum and discussed the effects of tuber propagation on the off-site propagation of wild buckwheat in different geographical environments. These results showed that the tuber reproduction of F. cymosum was relatively better， and it was conducive to its outcrossing and fruiting after a large population was formed by off-site reproduction. The differences on the altitude of habitat， climate condition and breeding site might cause influence on the germination， growth and reproduction of wild F. cymosum. The geographical conditions and local climate at Zhaojue County of Yunnan province were suitable for the off-site reproduction of F. cymosum. Collectively， these results might provide certain reference for ex situ propagation and conservation of F. cymosum.

Abstract:Using artificial inoculation technique， a total of 166 sorghum male-sterile and maintainer lines which introduced from the countries of the USA， India， Australia and China， were evaluated for resistance against the diseases of sorghum target leaf spot （TLS） and sorghum anthracnose （SA） at 2019 and 2020. The results showed 26 accessions highly resistant （HR） to target leaf spot accounting for 15.66%. Thirty-four accessions rated as resistance （R） to TLS accounted for 20.48%， and 42 accessions rated as moderately resistance （MR） to TLS accounted for 25.30%. Forty-six and 18 accessions， which were rated as susceptible （S） and highly susceptible （HS） to TLS， accounted for 27.71% and 10.84% respectively. There were eight accessions rated as highly resistant （HR） to sorghum anthracnose accounting for 4.82%. Eighty-four and 56 accessions rated as resistance （R） and moderately resistance （MR）， accounted for 50.60% and 33.73%， respectively. There were 14 accessions rated as susceptible（S） and 4 accessions rated as highly susceptible （HS） to SA， accounting for 8.43% and 2.41%， respectively. The results indicated that there was no resistance difference between sorghum male-sterile and maintainer lines to TLS. And there was no resistance difference between most male-sterile and maintainer lines to SA， except for Tx2790， 91NF18 and KSP335. The proportion of the USA resistance sources to TLS and SA was much larger than the other countries. Therefore， the introduction and improvement of foreign germplasm resources should be strengthened. Thirty-eight accessions were found being simultaneously resistant to both TLS and SA， including 20 American accessions， 16 Chinese accessions and 2 Indian accessions. These resistant sources used in sorghum breeding should aid in expanding the resistance gene diversity and in the development of new resistant varieties.

Abstract:Docynia delavayi （Franch.） Schneid. is a well-known wild fruit tree in Yunnan Province， whose fruit is rich in nutrients and ideal green fruit. The fruit is rich in tannins， crude fibres and flavonoids， resulting in most of the fruit being sour and difficult to eat fruits directly. The preliminary resource survey of Docynia delavayi （Franch.） Schneid. revealed abundant natural variations on fruit. For example， some of them showed a better taste of sweet juice and crispy flesh. Therefore， this study attempted to screen out the fresh Docynia delavayi. In this study， 100 fresh-feeding plants from Nuozadu Township， Lancang County， Yunnan Province， China， were analyzed for their fruit phenotypes （fruit weight， fruit cross diameter and fruit longitudinal diameter）. Based on the average fruit weight of 61.28 g as cutoff， 66 plus plants were obtained， followed by quantifying the quality traits， such as total sugars， total acids， Vc， flavonoids， tannins， crude protein， and crude fibre. There were phenotypic variations at all traits， among which the content of Vc was the most variable with a coefficient of variation of 0.318， and the content of total sugar was the most stable with a high overall consistency with a coefficient of variation of 0.064. Based on the correlation analysis， except for crude protein content that was significantly negatively correlated with flavonoid content， the other indicators were detected with positive or negative correlations without significance. The comprehensive scoring method was used to score and rank the initial selection of superior plants （the higher ranking with better overall quality）， and finally the lower limit of significantly lower than average scores was determined according to the one-sample mean hypothesis test. Thirteen fresh-feeding individuals with a total score higher than the lowest lower limit （56.13） were identified， of which the first one was No. 98 with a score of 66 and the best overall performance， and the rest of the plus trees are， in descending order of overall score： 1， 15， 34， 12， 76， 9， 77， 8， 71， 7， 99， 6. Collectively， this study obtained 13 plus trees of Docynia delavayi， thus providing raw material for the future breeding of improved varieties of fresh Docynia delavayi.