2022, 23(3):627-635. DOI: 10.13430/j.cnki.jpgr.20220125002
Abstract:Crop germplasm are the material basis for promoting the innovation of modern seed industry， the “chip” for stimulating the high-quality development of agriculture，and the strategic resources for ensuring national food security，building ecological civilization and maintaining biodiversity. Effective management of germplasm is an important part of their safety protection and efficient utilization. This study analyzed the management system as well as the protection and utilization system of crop germplasm from international organizations such as the United Nations Food and Agriculture Organization，the United Nations Environment Programme and the International Union for the Protection of New Varieties of Plants，and introduced the current status of laws and regulations as well as financial support and operation mechanism for germplasm resources， taking the United States，Japan，Brazil and India as examples；introduced the three development stages，including the government-led stage，the technical department responsible stage under the administrative guidance as well as the legal management stage，of germplasm resources management in our country，and expounded the domestic current management system，operation system and guarantee mechanism of germplasms；put suggestions on the key work of national germplasm management in the future to promote the protection and utilization of germplasm resources，combining with the development status and trend of domestic and foreign germplasm management and learning from the good practices of international germplasm resources management.
2022, 23(3):636-643. DOI: 10.13430/j.cnki.jpgr.20211206002
Abstract:Profiting from the development in the past nearly hundred years，the national integrated conservation system for crop germplasm resources has been well established based on ex situ and in situ conservation strategies，which important points：（1）for each type of crop germplasm，it is necessary to develop suitable conservation methods/technologies according to its biological characteristics，and conservation and utilization needs，to achieve preservation the genetic integrity or potential evolutionary ability，（2）each crop germplasm needs to be combined with a variety of preservation methods，to achieve integrated conservation of its gene pool，（3）at the national（regional）level，it is necessary to adopt in situ and ex situ conservation methods，as well as medium-term，long-term and backup preservation mechanisms to conservation the diversity， integrity and security of germplasm resources for sustainable use. By the end of 2021，China has built 55 ex situ conservation facilities，including long-term，medium-term，duplicate，field，in vitro，and cryo genebanks，and 214 in situ conservation sites，which has ability to achieve the integrated conservation of crop germplasm resources at the national level，and the total amount of conservation has reached 528000 accessions，providing a solid material foundation for crop breeding，seed industry development and agricultural innovation. This article reviewed the development history，scientific basis，and application practices in China and abroad of the integrated conservation system，in order to promote the conservation and utilization of crop germplasm resources.
2022, 23(3):644-653. DOI: 10.13430/j.cnki.jpgr.20211106002
Abstract:Saline-alkali field is an important reserve of arable land resource in agriculture. However，high salinity-alkalinity severely limits the cultivation of crops on saline-alkali soil. The development of crops suitable for growing in saline-alkali soil would be of significant importance in ensuring the food security. In recent years， salt-tolerant rice varieties have become primary candidates for improvement and exploitation of saline-alkali soil. Therefore，the genetic improvement of salinity tolerance has become an important research area in rice breeding. High-level salt stress inhibits the growth and development of rice at all different stages，causing significant reduction in yield and quality. Study on the molecular mechanism of salinity tolerance is of theoretical significance in guiding the development of salinity-tolerant rice varieties. In this review，we summarize the progress of studies on molecular mechanisms of salinity tolerance in rice which involve ion homeostasis regulation，osmotic regulation，antioxidant regulation，stomatal regulation，and signaling regulation. We further summarize the progress of genetic improvements of salinity tolerance in rice，especially highlighting the characterization of functional genes as negative regulators in salinity tolerance and candidates for genome editing-based molecular improvement. We also discuss future research focuses and experimental strategies that would provide a reference for developing highly salt-tolerant rice varieties with elite agronomic traits.
2022, 23(3):654-669. DOI: 10.13430/j.cnki.jpgr.20211119001
Abstract:Based on the literatures published on Web of Science and CNKI，this article applied the literature measurement method and knowledge map visualization technology in CiteSpace software，to make statistical analysis of the literatures that report functional genes of Orchidaceae from 2002 to 2020. We reviewed the exploration history and achievements on deciphering functional genes of Orchidaceae by national and international researchers in the past 19 years，and reported the characteristics such as the publication year，author and country information，journal co-citation analysis，knowledge base，hotspot keywords and research topics. Moreover，we further discussed the problems that remain to be solved and future research interests，thus providing theoretical supports in exploration，innovation and application of orchids in future.The results showed that the study of functional genes in Orchidaceae went through three stages （formation stage，growth stage and stable development stage），and the overall volume of publications showed a steady increase. Secondly，the research hotspots focused on the directions of speciation，transcriptomics，genetic transformation，ISSR and ITS molecular marker technology. The functional genes were mainly MADS-box，ACSs，MYBs and other genes，of which the MADS-box genes involved in regulating the development of flower organs were the most widely studied. Finally，a core group of authors has been formed，including Chen HW，Tsai WC，Tamura K，Liu ZJ，Zhu ZL，Cui B，Sun CB and Wu JS，but the cooperation between the teams is relatively dispersed.
2022, 23(3):670-677. DOI: 10.13430/j.cnki.jpgr.20211111001
Abstract:In plants，anthocyanins are a group of flavonoid compounds and play an important physiological role in fruit coloring and tolerance to stresses. Foods rich in anthocyanins also have good health effects on the human，such as anti-aging and preventing hardening of the arteries. The biosynthesis and accumulation of anthocyanins are not only affected by their own structural genes，regulatory genes and plant hormones，but also by external environmental factors（such as light，temperature，etc.）. Among them，light is one of the important factors affecting the synthesis and accumulation of anthocyanins in plants. Therefore，it is of great biological significance to analyze the regulatory mechanism of plants from receiving light signals to affecting anthocyanin synthesis. HY5（ELONGATED HYPOCOTYL5）encodes an alkaline leucine zipper（bZIP）transcription factor， plays an important role in regulating plant growth and development. It is the first transcription factor found to be involved in photomorphgenesis. It also plays a key regulatory role in the biosynthesis of anthocyanins. Here，we review the role of HY5 protein in the pathway of anthocyanin synthesis，responses to light signals and activation of downstream transcription factors and structural genes，and interaction with BBX protein in regulation of anthocyanin synthesis and accumulation. We expect to provide insights for future exploring the functional basis of HY5 in the metabolic pathways of flavonoids and responses to light signals.
2022, 23(3):678-690. DOI: 10.13430/j.cnki.jpgr.20211206001
Abstract:Wheat Leaf rust seriously distablizes the wheat production in China. Breeding wheat cultivars with durable resistance is considered as one of the most economical and effective methods in disease control. In this study，the Leaf rust resistance in 63 advanced wheat lines were analyzed by combining marker-assisted identification of known resistance genes，pedigree analysis and the field test upon Leaf rust infection. These genotypes together with 36 donor lines（carrying known Leaf rust resistance genes）were inoculated with 17 Puccinia triticina（Pt）races with specific virulence at the seedling stage，and also genotyed using 10 molecular markers associating with known resistance genes. Moreover，these 63 wheat advanced lines were evaluated for Leaf rust severity in Zhoukou city of Henan province and Baoding of Hebei province in the crop season（2018- 2019），followed by analyzing variance and calculating the LSD value to identify wheat lines that showed adult plant resistance. Out of 63 lines，18 lines were detected with Lr26，14 harboring Lr45，11 harboring Lr17，as well as 10 lines harboring Lr1. Any of three genes Lr10，Lr11，and Lr46 was found in 2 lines，while either of Lr2a， Lr2b，Lr15 and Lr37 was present in one line. Interestingly，a total of 17 lines showed slow rusting resistance at adult plant stage. Altogether，this study identified many wheat advanced breeding lines containing Leaf rust resistance genes，thus valuable in genetic improvement of wheat cultivars showing Leaf rust resistance.
2022, 23(3):691-705. DOI: 10.13430/j.cnki.jpgr.20211029001
Abstract:In order to collect and evaluate the wild germplasm resource for Sesuvium portulacastrum（L.） L. in the Hainan Island，we conducted five times of sample investigation in the coastal areas around the Hainan Island through eastern and western lines. Sixteen wild populations of S. portulacastrum（L.） L. were found from 11 cities or counties. We further collected information of the geographical distribution，growth environment，and associated plants for these S. portulacastrum（L.） L. germplasms. By analyzing their distribution characteristics， we found that S. portulacastrum（L.） L. was mainly distributed in beach and coastal areas with an average elevation about 7.4 m，ranging from north latitude 18°14′-20°05′ N to east longitude 108°39′-110°59′ E. 27 associated plants for S. portulacastrum（L.） L. were observed. We further analyzed the morphological and physiological characteristics of these plants under different salt conditions，followed by the principal component analysis to evaluate their salt tolerance ability. The wild germplasms collecting from Jiangnancheng in Haikou City and Qinglan Port of Wenchang City showed higher salt tolerance，whereas the samples from Yangpu Xinyingwan in Danzhou City and Yanjin Village in Lingshui Li Autonomous County were more salt-sensitive. Altogether，this study achieved a systematic investigation of the wild S. portulacastrum（L.） L. germplasm resource in Hainan Island，and found several wild germplasm resource which served as valuable materials to unlock the molecular mechanism for salt tolerance in S. portulacastrum （L.） L..
2022, 23(3):706-721. DOI: 10.13430/j.cnki.jpgr.20211114002
Abstract:The accurate identification of germplasm accessions is the prerequisite and basis for the diversity research on seed industry and industrialization development in quinoa（Chenopodium quinoa Willd.）. In this study，the multiple PCR amplicon capture technology（MultipSeq）was adopted to obtain 656 SNPs used for the genetic diversity analysis of 251 quinoa germplasm accessions，and perl scripts were adopted to construct DNA fingerprints of each accession and personal ID cards were constructed based on the fingerprint information. The analysis of the population genetic structure showed that 251 germplasm accessions were divided into two subgroups Ⅰ and Ⅱ，corresponding to the Andean high-altitude quinoa groups and the Chilean low-altitude quinoa groups. The Ⅰ and Ⅱ population genetic diversity index（π values）were 0.0037 and 0.0036，respectively. The population differentiation index（Fst value） is 0.14. The results of the population principal component analysis are completely consistent with the results of population genetic structure，and there are some genetic crossovers between subgroups. Phylogenetic analysis shows that Ⅰ group includes 152 germplasm accessions mainly from Bolivia and Peru，and Ⅱ group includes 99 germplasm accessions mainly from Chile. TheⅠgroup is further divided into two subgroups Ⅰ-1 and Ⅰ-2. The Nei′s genetic distance between Ⅰ-1 and Ⅰ-2 was 0.054. Among the 112 germplasm accessions from Shijiazhuang（Hebei），40，24 and 48 accessions were closely related to the Bolivian，Peruvian and Chilean germplasm in kinship relationship，respectively. The construction of molecular ID among 251 germplasm accessions could play an important role to trace and protect the quinoa germplasm in this study. The results of population genetic diversity analysis have certain reference significance for the classification and systematic arrangement in quinoa germplasm in China.
2022, 23(3):722-730. DOI: 10.13430/j.cnki.jpgr.20211104001
Abstract:The peanut pod abscission ability，which is the difficulty of pod shedding after maturity，is mainly related to the fracture force of gynophore-pod and gynophore-stem. In order to explore the variation of pod abscission among different peanut varieties，the fracture force of gynophore-pod and gynophore-stem of 294 genotypes were systematically measured and analysed at the beginning of harvest and after drying for 4 days in this experiment. The results showed that there were significant differences in fracture force of gynophore-pod and gynophore-stem among different peanut varieties. The variation of the gynophore-pod fracture force among 294 germplasms at the beginning of harvest and after drying for 4 days were 2.07-20.07 lb and 1.73-9.64 lb respectively，while the variation of the gynophore-stem fracture force was 2.21-22.86 lb and 1.90-11.25 lb respectively. The variation of gynophore-stem fracture force was observed at the beginning of harvest. The correlation between the characteristics of pod abscission and the main stem height and the number of pods per plant was not significant. Nine and 20 peanut varieties with suitable pod abscission ability after harvest and drying were screened respectively，which laid elite germplasm resource to breed new varieties of peanuts suitable for mechanized harvesting.
2022, 23(3):731-737. DOI: 10.13430/j.cnki.jpgr.20211112001
Abstract:To clarify the bacterial pathogen causing sugarcane leaf scald in west of Guangdong province， we conducted field surveys of leaf scald regarding 27 newly-introduced sugarcane varieties in two calendar years （2019 and 2020）. For 15 sugarcane stalk samples of suspected diseased plants，isolating the pathogen（s）and molecular identification by PCR were further performed. Based on the results of field trials，eleven sugarcane varieties were found with the typical symptom of leaf scald. Among them，the diseased plants from four varieties GT08-1589，DZ12-88，FN11-2907，and FN09-7111 were found in both the plant cane and ratoon cane，with incidence rates from 0.2% to 9.4%. The bacteria isolated from 15 diseased stalks were detected by PCR with the specific primers XAF1/XAR1 of Xanthomonas albilineans. These fragments are 608 bp in length and share 100% sequence identity to the published nucleotide sequences of X. albilineans isolates in China，USA，and France. These isolates were clustered in the same clade（PFGE-B）. Altogether，our results confirmed that leaf scald occurred in 11 cultivars from Zhanjiang sugarcane-planting region was caused by X. albilineans.
2022, 23(3):738-745. DOI: 10.13430/j.cnki.jpgr.20211021003
Abstract:The high rate of albino plants is an issue in wheat anther culture system. In this study，carbon sources with different components were selected to optimize the anther culture system，followed by evaluating the culture ability of 22 wheat varieties （lines） samples harvested at two consecutive years. The anthers cultured in vitro with Sinopharm sucrose did not produce embryoids，whereas anthers succeeded in dedifferentiation into embryoids and further regenerate plantlets when using maltose from Sigma and Phytotech. No significant difference in the green plantlets per 100 anthers，but a significant difference in the albino plantlets per 100 anthers between the two kinds of maltose were observed. The albino plantlets per 100 anthers using Sigma maltose was significantly higher than that using Phytotech maltose. Moreover，the green/albino plantlets per 100 anthers was significantly different among 22 varieties （lines）. The genotypes showing high green plantlet regeneration ability were henong 6425 （33.97%），Luomai 28 （22.28%） and Zhengmai 136 （15.63%），and the genotypes showing high albino plantlet regeneration ability were Xiaoyan 22 （39.69%），Zhengmai 136 （33.99%）， Luomai 28 （42.17%） and Yunong 903 （28.59%），and the genotypes showing high plantlet regeneration ability were Xiaoyan 22 （46.69%），Zhengmai 136 （49.62%），Luomai 28 （64.45%），Henong 6425 （41.47%） and Yunong 903 （31.69%）. Through identifying the genotypes with high regeneration ability，this study provided the genotypes suitable for haploid breeding，gene mapping and genetic transformation in common wheat.
2022, 23(3):746-754. DOI: 10.13430/j.cnki.jpgr.20211109002
Abstract:High sugar content germplasm is the basic resource for succeeding the breeding of high sugar varieties in sugarcane（Saccharum officinarum L.），and evaluation of its genetic variation is important for improving the breeding efficiency. In this study，the variance and genetic parameters（genetic variance，broadsense heritability and coefficient of variation and so on）in sucrose content were evaluated using 292 germplasm entries，based on three years（one plant and two ratoon crops）field experiments. The sucrose content among the genotypes were significantly different. The interaction between years and genotypes was not significant，and a high broad-sense heritability（0.85，based on 3-year trial）was found. A considerably broader variation with a mean of 10.66% was observed，while the coefficient of variance（CV）was relatively low with an average of 10.13%. That was possibly caused by the constitution of the germplasm involved in this study as most of the entries were released cultivars. Moreover，we found that CV was highest in the month of November regardless of plant or ratoon crops，and the phenotypic and genetic correlation coefficient reached to 0.94 and 0.95（P<0.001）， respectively，implying that selection in November or earlier may be good for sucrose content selection. As a result，32 genotypes with high sugar content（more than 16.00%）were obtained and qualified as high sugar parental germplasm resource for sugarcane breeding. We further proposed some suggestions for high sugar breeding in sugarcane.
2022, 23(3):755-767. DOI: 10.13430/j.cnki.jpgr.20211105001
Abstract:Through the determination of phenotypic traits of 43 wolfberry materials，combined with SSR molecular marker technology，the population structure and genetic diversity between ancient wolfberry trees and existing wolfberry varieties in Ningxia were comprehensively analyzed. The principal component analysis results of phenotypic traits determined that the principal component was 4，and the cumulative contribution rate reached 78.09%. The leaf size of the first principal component and the fruit size of the second principal component played a major role. The coefficient of variation ranged from 15% to 54%，with an average of 26.78%，and the genetic variation index ranged from 5.26 to 5.41. The phenotypic traits were divided into 4 groups by cluster analysis，3 individuals in group I，3 individuals in group II，8 individuals in group III and 29 individuals in group IV. Five materials with excellent comprehensive properties were determined by membership function method，namely L14，L16，L28，L40 and L43. The average effective alleles of SSR molecular markers were 2.018，the average expected heterozygosity was 0.398，and the average Shannon ′ s index was 0.839. The optimal K value of SSR molecular markers was 4. Among the five materials with better comprehensive evaluation，L16 showed heterozygous genotype，and L14，L28，L40 and L43 showed single genotype. In this study，a variety of methods were used to comprehensively analyze the phenotypic traits and genetic diversity of ancient wolfberry trees from different sources and ages，which provided a theoretical basis and practical guidance for the subsequent utilization of ancient wolfberry germplasm resources and the breeding of wolfberry varieties.
2022, 23(3):768-774. DOI: 10.13430/j.cnki.jpgr.20211227001
Abstract:Himalayan region of Qinghai Tibet Plateau is the origin center of buckwheat. The specific climate and geographical location of this region enabled the appearance of abundant wild buckwheat resources. In order to uncover the populations of buckwheat and their distribution in Xizang Autonomous Region，the wild buckwheat resource investigation team of Chinese Academy of Agricultural Sciences conducted a survey and collection for 40 days from 2020 to 2021. Focusing on the important areas including Jinsha River，Lancang River，Brahmaputra River，Niyang River，Palong Zangbo and other rivers in Changdu，Nyingchi，Shannan，Lhasa and Shigatse，189 buckwheat wild plant germplasm accessions were collected in this five areas （122 Fagopyrum tataricum subsp. potanini，36 F. cymosum（Trevir.） Meisn.，10 F.esculentum subsp. ancestrale，8 F. gracilipes（Hemsl.） Dammer ex Diels，5 F. gilesii（Hemsl.） Hedberg，5 F. jinshaense Ohsako & Ohnishi，2 F. leptopodum Hedberg and 1 F.homotropicum）. The abundant phenotypic variation among species collected from this region and significant difference in characteristics if compared to wild buckwheat accessions in other areas were observed. Since wild relatives of buckwheat has some elite characters，they might serve as a gene resources valuable for buckwheat breeding.
2022, 23(3):775-786. DOI: 10.13430/j.cnki.jpgr.20211207001
Abstract:From 2015 to 2020，relying on The Third National General Survey and Collection Action on Crop Germplasm Resources，Thirty-five agriculture-related in Chongqing districts and counties were surveyed. The distribution and biological classification of vegetable germplasm resources collected were analyzed. A total of 428 vegetable germplasm accessions from 35 species of 30 genera of 14 families were obtained. These germplasm accessions were mainly distributed at the three Gorges Reservoir area and the main urban areas of northeast Chongqing，accounting for 51.17% above 800 meters above sea level. Most of them were distributed in areas with a population density of less than 500 people /km2 . Beans，melons and mustard accounted for the largest proportion. Through the identification and evaluation， sixty-four resources with excellent performance in high yield， resistance to diseases and insects，and stress resistance were screened out，of which six were suitable for cultivation with potentially commercial interest，namely Sanyuan luffa，Malva，Dioscorea alata L.，Dingjia cardamine， Qingcaoba radish，Wine jug radish . This study will provide data support for the research on the diversity of vegetable germplasm resources，germplasm innovation，and new variety breeding in Chongqing municipality of China.
2022, 23(3):787-799. DOI: 10.13430/j.cnki.jpgr.20211218001
Abstract:DELLA proteins are known as negative regulators of gibberellin involved in plant flowering. Eight DELLA genes were identified in soybean genome by sequence alignment with Arabidopsis thaliana（L.） Heynh. DELLA orthologs GmGAI3a has only one GRAS domain，and the other seven DELLA proteins have both DELLA domain and GRAS domain. By performing gene-based association analysis of flowering time in natural population，soybean DELLA haplotypes associating with early-flowering have been detected in soybean accessions collected from the middle and high latitude of China，speculating DELLA genes as negative factors in regulating flowering. CRISPR/Cas9-based editing in soybean hairy root system revealed the editing efficiency at the target sites. Identification of the CRISPR/Cas9 targets of seven DELLA genes provided references for generating stable transgenic DELLA mutants for deciphering their biological functions.
2022, 23(3):800-810. DOI: 10.13430/j.cnki.jpgr.20211117001
Abstract:Early maturity is one of the target traits in upland cotton（Gossypium hirsutum L.）breeding，and identification of QTL related to early-maturity is of practical value. In our study，we crossed early-maturity 019 line（EM019）with a late-maturing cultivar Lumianyan 37（LMY37），followed by continuous self-pollination and construction of a recombinant inbred line（RIL）population composed of 312 lines. The RIL population was planted in Linqing（2019，2020 and 2021）and Xinjiang（2019）. We used composite interval mapping （CIM）method to detect quantitative trait locus（QTLs）underlying the flowering time（FT），percentage of open bolls（POB），boll weight（BW）and lint percentage（LP）. A total of twenty-one early-maturity QTL had been identified，and seven QTL were detected with the additive effect ranging from 0.3 to 1.01，explaining 2.56%~17.71% of the phenotypic variation. Eight QTL associating with POB were identified with the additive effect of 5.81~-2.39，explaining 4.66%~20.44% of the phenotypic variation. These QTL were mainly distributed on Chromosomes A05，D03 andD08. A QTL cluster was found on Chromosome D08，in which 124 candidate genes were annotated based on the transcriptome data of LMY37 and EM019 at different true leaf stages under long and short day treatments. Three strong related genes namely GH_D08G0636，GH_D08G0684 and GH_ D08G0948，have been identified. Altogether，these QTL identified from this study provided insight for future deciphering the molecular mechanisms of early-maturity related traits in cotton.
2022, 23(3):811-822. DOI: 10.13430/j.cnki.jpgr.20211203002
Abstract:qSsnps-5D，derived from the backbone parental line Jing 411（J411），is a major stable QTL for sterile spikelet number per spike（SSNPS）. This study aimed to decipher the genetic effect of this QTL and its use in wheat varieties. Two populations，including a recombinant inbred lines derived from the cross of Kenong 9204（KN9204）and Jing 411（KJ-RIL），and a natural mapping population comprised by 314 wheat authorized varieties or advanced lines，were involved. The experiment results showed that qSsnps-5D was confirmed in an interval of 3.41 Mb from 0.72 Mb to 4.13 Mb on chromosome 5D among 8 datasets. Excellent allele of qSsnps5D from J411 could increase spikes per plant but significantly decrease thousand kernel weight in both KJ-RIL and the natural mapping populations. However，the genetic effects of qSsnps-5D on kernel number per spike and yield per plant were differing between the two populations. Two close linkage markers of qSsnps-5D，i.e.，AX110565536 and AX-86170796 were used to specify the breeding utilization characteristics of qSsnps-5D in the natural mapping population. The excellent haplotype for qSsnps-5D（Hap-GG-CC）was often found（80.60%） in the foreign varieties. Among the Chinese varieties，higher rates of excellent haplotype（Hap-GG-CC）were found from varieties of Qinghai province，Sichuan province and Henan province，but the rates of haplotype HapGG-CC were lower in varieties of Shandong，Beijing，Shaanxi and Hebei. The rates of Hap-GG-CC in varieties released from 1980 s to present were constantly declined. To facilitate the application of qSsnps-5D in future molecular breeding programs，we developed a PCR-based InDel molecular marker named as 5D-1620921. Altogether，this study provided insights for the application of qSsnps-5D in molecular breeding programs of wheat.
2022, 23(3):823-831. DOI: 10.13430/j.cnki.jpgr.20211124001
Abstract:Drought stress is one of the most important constraints affecting maize growth and development and therefore resulting in yield loss. Thus，it is essential to understand molecular mechanisms of drought stress responses in maize and excavate excellent drought-tolerant germplasms and genes for drought tolerance improvement. In our previous studies which based on the transcriptomic comparison of two maize inbred lines with contrasting drought tolerance，a member of HD-Zip transcription factor family，Zmhdz6，was obtained as an important candidate gene for drought tolerance. In the present study，we conducted a functional analysis of Zmhdz6. The phylogenetic analysis of HD-Zip family in maize showed that Zmhdz6 had closer relationship with Zmhdz4，which has proven could improve drought tolerance of transgenic plants. The expression of Zmhdz6 was induced by drought and ABA treatment. The coding sequence of Zmhdz6 in H082183 and Lv28 occurred five SNPs causing three amino acid differences，but all of the SNPs were not in HD or LZ domains. The transgenic Arabidopsis thaliana L. overexpressing Zmhdz6 showed smaller blades，shorter plants and enhanced drought tolerance. These results indicated that Zmhdz6 is an important and potentially valuable gene for the improvement of drought tolerance in maize. Therefore，this study provides theoretical support and genetic resource for droughttolerant maize breeding.
2022, 23(3):832-841. DOI: 10.13430/j.cnki.jpgr.20211223002
Abstract:The tassel branch number of maize is one of the important factors affecting the yield production. Unlocking the QTL loci to control the tassel branch number of maize is of great significance for maize variety improvement and molecular assisted breeding. In this study，the individuals of a BC1F1 population derived from the parents Jing724 and Jing92 of Jingke968 were genotyped using high-throughput high-quality SNP array Maize6H-60K. By taking use of 28910 polymorphic SNPs，a high density genetic map containing 2737 BIN markers was constructed. The number of BIN markers on each chromosome ranged from 145 to 512， and the average genetic distance was 0.56 cM. Both parents and 727 offspring lines were planted in Beijing in 2021 to investigate the tassel branch number，followed by QTL mapping using Inclusive Composite Interval Mapping（ICIM） in software QTLIciMappingV4.2. A total of 6 QTL were detected，located on chromosomes 2，5，6，7，8 and 9，respectively. The LOD score of QTL ranged from 3.18 to 11.08，revealing 1.58% to 5.59% phenotypic variation. While four QTL were located in the same or adjacent area as previously reported，two novel QTL qTBN6 and qTBN7 have been revealed. The LOD of qTBN6 was 6.73，and the synergistic allele derived from Jing724，with a negative additive effect to reduce the tassel branch number. Collectively， this study laid a foundation for future isolating the functional genes that regulate the tassel branch number in maize.
2022, 23(3):842-856. DOI: 10.13430/j.cnki.jpgr. 20211208002
Abstract:Long non-coding RNAs（lncRNAs）are functional RNA molecules with>200 nucleotides in length，and play an important regulatory role in the growth and development of plant. We previously identified a salt stress-related lncRNA in soybean，called lncRNA77580. Deletion and overexpression of lncRNA77580 were found to alter the expression of several neighboring protein-coding genes. In this study，we explored the function and regulation network of lncRNA77580 by the transcriptome analysis of lncRNA77580 transgenic hairy root. Over-expressing lncRNA77580 in soybean hairy roots showed salt sensitive. We generated the edited lines harboring>4kb fragment deletion in lncRNA77580 using dual-sgRNA/Cas9 technology（mutation efficiency：12.5%）. By conducting the transcriptome sequencing on the hairy roots with lncRNA77580 overexpressing or knockout，significant changes on transcriptional profiles of the transgenic hairy roots were detected. GO enrichment and KEGG pathway analysis of differentially expressed genes（DEGs）showed that overexpressing or knockout of lncRNA77580 had modified the transcriptional profiles in a large number of transcription factors and signaling genes，which are annotated to be related with plant stress response and plant growth and development. Collectively，these results suggested that lncRNA77580 is a long non-coding RNA with important functions in stress response of soybean and plant growth and development.
2022, 23(3):857-870. DOI: 10.13430/j.cnki.jpgr.20211122003
Abstract:Stress associated proteins （SAPs） play an important role in plant response to abiotic stress，but there was little information about the SAP family and function of its member in wheat. In this study，62 SAP genes were identified from wheat，and analyses of these members were conducted combined phylogenetic tree， gene structure and constitutive motifs. The expression pattern of TaSAP1；1，a member belongs to SAP family and responding to low-Pi stress in our previous study was investigated by qRT-PCR，and the results showed its expression increased after both stresses. Biodiversity analysis revealed that there was diversity of TaSAP1；1 gene and subcellular localization analysis showed that TaSAP1；1 targeted onto nucleus. The expression vector was constructed and transformed into tobacco to obtain the overexpression lines （OE）. Combined phenotypic analysis and parameters comparison such as fresh weight，leaf area and chlorophyll content in plants of OE lines and wild-type （WT），it was showed that overexpression of TaSAP1；1 in tobacco not only enhanced the tolerance of seedlings to salt stress，but also to low-Pi stress. The improved tolerance may be related to the increased stomatal closure rate resulting from up-regulation of some ABA signal pathway related genes （NtSAPKs），and the increased expression of some phosphate transporters （PTS） genes，respectively. In addition，the interaction between TaSAP1；1 and a transaminase named TaAMTR detected by yeast-two hybridization assay may also be involved in the process of stress resistance. The results not only enrich the understanding of wheat SAP family， but also have a new insight on the function of its members involved in abiotic stress，which provides a theoretical basis for the genetic improvement of crop comprehensive stress resistance.
2022, 23(3):871-880. DOI: 10.13430/j.cnki.jpgr.20211115001
Abstract:To elucidate the molecular mechanism of leaf erectness in wheat，this study analyzed the differentially expressed genes （DEGs） using the transcriptome sequencing in a wheat erect leaf mutant MtHS29，which was identified using fast neutron irradiation in the wild type cultivar Heng S29 . The leaves from MtHS29 were observed with degrees of deficiency with leaf pillow，ligule and auricle，in which the flag leaf and the second leaf from top lacked all of these structures and their leaf angles approached to zero. A total of 1567 DEGs were found in the leaf pillow of the second，third and fourth leaves from top between MtHS29 and WT. These genes were enriched in the pathways of plant hormone signal transduction，starch and sucrose biosynthesis，phenylpropanoids biosynthesis，endoplasmic reticulum protein processing，and amino acid and nucleotide glucose metabolism，etc. A proportion of DEGs in MtHS29 were annotated closely associating to regulating the cell division and cell expansion in the proximal and distal axial surfaces of the leaf pillow，and to deficiency of leaf pillow，ligule and auricle in mutant. Several genes involved in the synthesis of cell wall components，synthesis and signal transduction of Auxin and Brassinosteroids，and regulation of plant organ morphogenesis were found. Collectively，this study provided new germplasm in wheat breeding for plant architecture，and insights for future deciphering the molecular mechanism of the erect leaf architecture in wheat.
2022, 23(3):881-894. DOI: 10.13430/j.cnki.jpgr.20210910001
Abstract:To explore and utilize the genetic resources of good quality traits in wheat landraces，15 quality trait-related genes in 405 wheat landraces of Shanxi province were genotyped using 30 KASP markers. The results showed that the average frequency of the favorable allelic variations Pinb-D1b and Pinb-B2b for grain hardness accounted for 4.94% and 63.46%，respectively. At the Glu-1 locus，the favorable alleles Glu-Ax1（or Glu-Ax2* ），Glu-Bx7OE and Glu-D1d accounted for 93.09%，47.16% and 0.74%，respectively. Elite alleles for flour color including， Psy-A1b，Psy-B1a（or Psy-B1b），Psy-D1a，TaPds-B1b，Zds-A1a，TaLcy-B1b，Lox-B1a，TaPod-A1b，Ppo-A1b and Ppo-D1a accounted for 1.23%，95.80%，87.65%，0.74%，87.16%，96.05%，88.89%，1.73%，97.28% and 20.94%， respectively. The favorable allele frequncy of landraces，which were derived from the late-maturing winter wheat region in central Shanxi and the south mid-maturing winter wheat region，ranged from 0.52% to 97.41% and 0 to 97.51%，respectively. In addition，nine favorable alleles Pinb-B2b/Glu-Ax1（or Glu-Ax2* ）/Glu-Bx7OE/Psy-B1a （or Psy-B1b）/Psy-D1a/Zds-A1a/TaLcy-B1b/Lox-B1a/Ppo-A1b were simultanously detected in 89 samples，with a frequency of 21.98%. By conducting marker-assisted identification of the excellent alleles in wheat landraces，this study provided reference for the genetic improvement at quality-related traits in bread wheat.
2022, 23(3):895-905. DOI: 10.13430/j.cnki.jpgr.20211209002
Abstract:In this study，we cloned the transcription factor gene FtMYB41 in tartary buckwheat cultivar Pinku-1. Sequence analysis showed that the MYB super gene family member FtMYB41 contained one 5′UTR and two introns，with the complete coding sequence of 705bp which encodes for 234 amino acids. Phylogenetic tree analysis showed that FtMYB41 protein had close homology with tomato NP_001234262.1 and tobacco NP_001312384.1. Transcriptional activation analysis revealed the transcriptional activation activity at FtMYB41 C-terminal. Moreover，the FtMYB41 gene had the higher expression in roots and was induced by drought and salt stresses. The expression level of FtMYB41 gene was significantly increased under drought stress for 9 h. Overexpressing FtMYB41 gene in Arabidopsis thaliana（L.）Heynh. and tartary buckwheat hair root resulted in improved drought resistance by increasing germination rate，increasing CAT and SOD activity，and decreasing MDA content.
2022, 23(3):906-916. DOI: 10.13430/j.cnki.jpgr.20211205001
Abstract:NAC transcription factors are known to be involved into responses to biotic and abiotic stresses in plants. In this study，we cloned by sequence homology 3 SsNAC genes from sugarcane wild species S. spontaneum L.，named as SsNAC2，SsNAC3 and SsNAC4. Bioinformatic analysis showed that the full-length coding sequences of SsNAC2，SsNAC3 and SsNAC4 were 931 bp，486 bp，and 781 bp，encoding 309，162 and 259 amino acids，respectively. The subcellular location prediction indicated that the deduced proteins of SsNAC2， SsNAC3 and SsNAC4 were localized in the nucleus. The promoters of SsNAC2，SsNAC3 and SsNAC4 were predicted with putative stress-responsive cis-acting elements including an ABRE，LTR，MBS，MYB and STRE. Phylogenetic tree analysis showed that SsNAC2 within the OsNAC3 subgroup was closely related to Sorghum SbNAC68 gene. SsNAC4 and its homolog gene sorghum SbNAC82 belonged to NAC2 subgroup，and SsNAC3 in the ATAF subgroup was closely related to Miscanthus MlNAC1. The tissue-specific analysis showed that SsNAC2 and SsNAC3 were highly expressed in stem and leaves. The transcription profile analysis showed that SsNAC2， SsNAC3 and SsNAC4 were variable on expression under different stress conditions. It′s speculated that SsNAC2， SsNAC3 and SsNAC4 might be involved in regulation of abiotic and biotic stresses including drought，low temperature，salinity，pathogenic fungi，etc. The transcripts of SsNAC2，SsNAC3 andSsNAC4 were inducible by ABA and MeJA treatments. These results provided theoretical basis for future deciphering the functions of NAC genes under stresses conditions in S. Spontaneum L.
2022, 23(3):917-925. DOI: 10.13430/j.cnki.jpgr.20211011002
Abstract:To study the transcriptional regulation mechanism of SpsLAZY1a and SpsLAZY1b genes， their promoter fragments were cloned from Salix psammophila C. Wang & C. Y. Yang. By analyzing cisacting element in the promoter sequences using plantCARE database，the promoter sequences of both genes contain the core elements CAAT-box and TATA-box，and the elements responding to light，methyl jasmonate， abscisic acid，ethylene，gibberellin，and low temperature. GUS staining in tobacco transient expression and stable transgenic 84K poplar revealed the transcriptional activity of both promoters ProSpsLAZY1a and ProSpsLAZY1b. The ProSpsLAZY1a activity was stronger than that of ProSpsLAZY1b in transgenic 84K poplar. The results of stem basal sections of transgenic 84K poplar showed that the expression of ProSpsLAZY1a and ProSpsLAZY1b was mainly observed in endothelium and phloem. The promoters of SpsLAZY1a and SpsLAZY1b genes were non-tissue-specific，and their activities of the promoters were different. Collectively，this study provides a reference for analyzing the regulation mechanism of LAZY gene.