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    12 December 2023, Volume 49 Issue 12
    • REVIEW
      Advances in heat-stress responses at sexual reproduction stage in plants
      CHEN Sai-Hua, ZHONG Wei-Jie, XUE Ming
      Acta Agronomica Sinica. 2023, 49(12):  3143-3153.  doi:10.3724/SP.J.1006.2023.32020
      Abstract ( 493 )   HTML ( 93 )   PDF (4257KB) ( 509 )   Save
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      The occurrence of extreme hot weather poses a threat to crop production. Heat stress suffered at reproductive stage in crops is always correlated with crop yield losses, and thus the underlying molecular mechanisms are of great significance in crop thermotolerance improvement. However, relevant studies are mainly focused on Arabidopsis and less is known in crops. From the perspective of plants, here, we reviewed the heat-stress responses at reproductive stage, including meiosis process, tapetum degradation, microspore development, pollen-tube germination, and fertilization, as well as seed development. Based on these advances, we proposed feasible strategies for thermotolerance improvement, which will pave a way for the breeding of heat-tolerant crop varieties.

      CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
      Creation of doubled haploid in wheat using distant hybridization and unreduced gamete genes
      LIU Xiao-Juan, LIU Xin, ZHANG Ming-Hu, HAO Ming, NING Shun-Zong, YUAN Zhong-Wei, HUANG Lin, LIU Deng-Cai, ZHANG Lian-Quan
      Acta Agronomica Sinica. 2023, 49(12):  3154-3161.  doi:10.3724/SP.J.1006.2023.31009
      Abstract ( 237 )   HTML ( 37 )   PDF (8357KB) ( 161 )   Save
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      The union of unreduced female and male gametes leads to spontaneous chromosome doubling, which is not only an important way of the origin of polyploid species but also an essential tool for enhancing crop doubled haploid breeding efficiency. A major quantitative trait locus QTug.sau-3B responsible for unreduced gametes formation was discovered in tetraploid Triticum turgidum wheat and was further transferred to elite common wheat lines using synthetic hexaploid wheat as a bridge. This objective of this study is to make wheat/wheat F1 hybrids between the elite lines with this gene region and commercial cultivars and to evaluate the efficiency of QTug.sau-3B gene leading to spontaneous chromosome doubling. Wheat/wheat F1 hybrids and their parents were pollinated with the fresh pollen of Imperata cylindrica to produce wheat haploid through chromosome elimination of I. cylindrica. Doubled haploid (DH) were then developed by spontaneous chromosome doubling in haploids because of the union of unreduced female and male gametes. In this experiment, 5 F1 hybrid materials and 3 I. cylindrica materials were used for distant hybridization. 4610 florets were pollinated, 1965 seeds were produced, 244 embryos were obtained, and 50 wheat haploid plants were obtained. In different temperature treatments, the haploid plant numbered H31 set seeds at 25℃/18℃ (18 h/6 h) and 25℃/10℃ (18 h/6 h), and the self-fertilization rate was 4.35% and 2.41%, respectively. The results of this study provide a reference for the establishment of wheat haploid breeding technology of chromosome elimination based on wheat-I. cylindrica hybridization and automatic chromosome doubling based on unreduced gamete genes.

      Evaluation of field waterlogging tolerance and selection of waterlogging-resistant germplasm resources of Brassica napus L.
      LI Ji-Jun, CHEN Ya-Hui, WANG Yi-Jin, ZHOU Zhi-Hua, GUO Zi-Yue, ZHANG Jian, TU Jin-Xing, YAO Xuan, GUO Liang
      Acta Agronomica Sinica. 2023, 49(12):  3162-3175.  doi:10.3724/SP.J.1006.2023.34034
      Abstract ( 246 )   HTML ( 24 )   PDF (12471KB) ( 404 )   Save
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      Brassica napus L. (B. napus) is one of the most important oil crops in China, and has high risk of waterlogging stress during its production. The objective of this study is to evaluate the field waterlogging tolerance and screen stable waterlogging-resistant germplasm resources. The appropriate waterlogging duration for waterlogging tolerance identification was determined under pot conditions first, and then the comprehensive evaluation and comparison of the waterlogging tolerance of 505 germplasm resources of B. napus were carried out. The stable extreme materials were screened in field experiments. The results showed that the growth of B. napus plants began to be affected after four-day-waterlogging, and severely inhibited after about 10-day-waterlogging under pot conditions. In the two-year field experiment, 27 indexes extracted using the UAV phenotype acquisition platform were converted into two common factors by factor analysis. The common factor 1 represented the growth state of B. napus under waterlogging, and the common factor 2 represented the physiological state. The comprehensive evaluation value of waterlogging resistance (D-value), which was calculated according to the load and variance contribution rate of the two common factors, divided the waterlogging resistance of B. napus germplasm resources into four types, including extremely waterlogging resistant type (Cluster I, 99 materials), waterlogging resistant type (Cluster II, 200 materials), sensitive type (Cluster III, 187 materials), and extremely sensitive type (Cluster IV, 19 materials). In the two-year field experiment, nine stable waterlogging sensitive materials and nine resistant materials were identified, and the results were confirmed by the field experiments in 2022. Moreover, in the two-year experiment, the vegetation indexes, MTVI2D, and MCARI2D had high correlations with the D-value, and the correlation coefficients were greater than 0.76, which can be used for rapid and efficient comprehensive evaluation of B. napus waterlogging resistance. In conclusion, the evaluation system and rapid and comprehensive evaluation methods for waterlogging tolerance of B. napus in the field were established, which were applied to analyze the types of waterlogging tolerance of B. napus germplasm resources and identify the stable waterlogging resistant and sensitive materials in this study, providing reliable evaluation methods and important germplasm resources for the research and genetic improvement of waterlogging resistance of B. napus.

      Transcription factor gene TaPHR1 involved in regulation spikelet number per spike in common wheat
      ZHANG Yi-Ning, ZHANG Yan-Fei, WANG Min, WANG Jing-Yi, LI Long, LI Chao-Nan, YANG De-Long, MAO Xin-Guo, JING Rui-Lian
      Acta Agronomica Sinica. 2023, 49(12):  3176-3187.  doi:10.3724/SP.J.1006.2023.31008
      Abstract ( 225 )   HTML ( 31 )   PDF (1607KB) ( 263 )   Save
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      The utilization of water elite genetic resources to develop new wheat varieties is an effective approach to deal with the challenges of climate change and rapid population growth. The MYB (v-myb avian myeloblastosis viral oncogene homolog) transcription factors are one of the largest families of transcription factors in plants and are involved in plant growth and development and in the regulation of biotic and abiotic stresses. In this study, 19 SNPs and 15 SNPs were identified in TaPHR1-4A and TaPHR1-4B, respectively, and the molecular markers were developed based on these SNPs. Association analysis showed that Hap-4B-I was the elite haplotype with high Total number of spikelet per spike (NCS). Hap-4B-I was further confirmed to be beneficial for improving wheat spike traits by creating two backcross introgression population lines. Fluorescence quantitative polymerase chain reaction of TaPHR1 revealed that the relative expression level of TaPHR1 genes in young spikelets of Hap-4B-I haplotype was higher than that of Hap-4B-II haplotype. In addition, the heterologous expression of TaPHR1 in rice resulted in more panicle branches, which also confirmed the involvement of TaPHR1 in the regulation of NCS. The geographic and temporal distribution of wheat modern varieties revealed that although Hap-4B-II accounted for the largest proportion of modern varieties in China, the proportion of Hap-4B-I was gradually increasing as wheat breeding time progressed. In conclusion, TaPHR1 was a positive regulator of NCS in wheat. Therefore, the molecular markers developed in this study could be an important source of marker-assisted selection and genetic improvement in wheat.

      Mapping and effect analysis of QTL for phenology traits in wheat using 55K chip technology
      WEN Ming-Xing, XIAO Jin, XU Tao, SUN Li, WANG Zong-Kuan, WANG Hai-Yan, WANG Xiu-E
      Acta Agronomica Sinica. 2023, 49(12):  3188-3203.  doi:10.3724/SP.J.1006.2023.31014
      Abstract ( 181 )   HTML ( 15 )   PDF (7423KB) ( 87 )   Save
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      Phenology is an important agronomic trait for common wheat, which has a great impact to explore its genetic mechanism and effect for wheat breeding and application. In this study, 240 recombinant inbred lines (RILs) derived from Yangmai 158 and Hiller were used to identify the phenology traits in 2-4 environments. A total of 52 QTL were detected on chromosomes 2A, 2D, 3D, 4B, 4D, 5A, 5B, 5D, 6A, 6B, 7A, 7B, and 7D by using the constructed high-density genetic map. QJS/BS/HS/FS/MS.nau-5D.2, QJS/BS/HS/FS/MS.nau-2D.1, and QJS/BS/HS/FS/MS.nau-7B.1 were detected for several years, which explained 4.56%-46.86%, 1.32%-33.40%, and 2.37%-13.27% of phenotypic variation, respectively. QBS/HS.nau-2A.3, QHS/FS.nau-5B.2, QFS.nau-2A.5, QBS.nau-6A.2, QJS.nau-4D.2, QJS.nau-6A.3, QBS.nau-2A.2, QBS/HS.nau-6A.1, QFS.nau-7A.2, QMS.nau-3D, QMS.nau-4D.1, and QMS.nau-6B.1 were new QTL. Pyramiding of multiple phenology loci with large effects or repeated is an effective approach to shorten the growth period in different degrees, which could be used to cultivate early-maturing and high-yield wheat varieties.

      Characteristics of MADS-box and SUPERMAN genes in tobacco cytoplasmic male sterile line K326
      CUI Fang-Fang, MENG Lin-Feng, LIU Miao-Miao, ZHANG Jian-Qiang, WANG Jian-Ge, LIU Qi-Yuan
      Acta Agronomica Sinica. 2023, 49(12):  3204-3214.  doi:10.3724/SP.J.1006.2023.24268
      Abstract ( 131 )   HTML ( 9 )   PDF (1902KB) ( 156 )   Save
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      Cytoplasmic male sterility (CMS) is an important tool for hybrid production and a good system for studying the interaction between nucleus and cytoplasm, but its mechanism is still unclear. The relationship between stamen abnormality and the relative expression levels of flower development genes in tobacco CMS line K326 was studied. The CMS line K326 was derived from a natural variation in Nicotiana tabacum and was bred by continuous backcross of flue-cured tobacco variety K326. It has not only stamens with carpelloid, but also stamens with petaloid, and the base of abnormal stamens is fused into a whole. In this study, we identified MADS-box genes and SUPERMAN genes of whole genome, which controlled the flower development in N. tabacum and analyzed their chromosomal localization and collinearity. The cis-acting elements of B genes and SUPERMAN genes were predicted, and their expression characteristics in flower buds at different stages in both CMS line and its maintainer line were studied. The results showed that 160 MADS-box genes and 5 SUPERMAN genes were identified in the genome of tobacco, including 4 PI genes, 3 AP3 genes, and 7 B genes. There were 79 MADS-box genes scattered on 22 chromosomes, and 3 SUPERMAN genes distributed on 3 chromosomes. Collinearity analysis showed that tandem and fragment DNA duplication and multiplication were the driving forces of the expansion of MADS- box gene family in tobacco. The abnormal stamens of CMS line K326 appeared at small bud stage, suggesting that the abnormal stamens in CMS line K326 were the result of early meristem development defects. The qRT-PCR showed that 7 B genes and 1 SUPERMAN gene were expressed both in CMS line K326 and its maintainers. The relative expression level of PI gene NitMADS115 in the maintainer line was higher than that in CMS line at all stages. The relative expression levels of AP3 genes NitMADS72 and NitMADS100 in maintainer lines were lower than those in CMS lines. Other genes were down-regulated at small bud stage and large bud stage, and up-regulated at middle bud stage. The SUPERMAN gene could only be detected at small bud and middle bud stage of the maintainer line, but not at bud stages of CMS line. Analysis of cis-acting elements showed that NitMADS115 had an auxin response element AuxRR. The study indicates that auxin might play an important role in cytoplasmic retrograde regulation of nucleus in tobacco.

      Detection and verification of QTL for plant height in Yangmai 4/Yanzhan 1 recombinant inbred lines population and their genetic effects on Fusarium head blight resistance
      ZHAO Die, HU Wen-Jing, CHENG Xiao-Ming, WANG Shu-Ping, ZHANG Chun-Mei, LI Dong-Sheng, GAO De-Rong
      Acta Agronomica Sinica. 2023, 49(12):  3215-3226.  doi:10.3724/SP.J.1006.2023.31005
      Abstract ( 159 )   HTML ( 18 )   PDF (3162KB) ( 76 )   Save
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      Plant height (PH) is associated with fusarium head blight (FHB) resistance in wheat. In this study, a recombinant inbred lines (RIL) population derived from the cross of Yangmai 4/Yanzhan 1 (YM4/YZ1) was used to mine the quantitative trait loci (QTL) of PH traits using 55K SNP (single-nucleotide polymorphism) chip data, combined with the PH data of RIL population and their parents in six environments for three continuous years. Soil surface inoculation method and single spikelet inoculation were used to identify the FHB resistance to infection (Type I) and spread (Type II), respectively. Seven QTLs related to PH were detected on chromosomes 2D, 4B, 4D, 5A, and 7D, and only QPh.yas-2D.2 may be a new QTL of PH after comparing with previous studies. The dwarfing effects of QPh.yas-2D.1, QPh.yas-2D.2, and QPh.yas-5A were derived from YM4, and the dwarfing effects of the other four QTLs were derived from YZ1. Both QPh.yas-4D and QPh.yas-5A could be detected in six environments, and phenotypic variation explained (PVE) rates ranged from 19.48%-44.11% and 10.48%-13.71%, respectively. The increasing alleles at the Rht-D1 and QPh.yas-7D.2 (YM4 allele) significantly reduced the average percentage of infected spikelets (PIS) by 34.97% and 19.09%, respectively. The dwarfing alleles at QPh.yas-2D.2 and QPh.yas-5A (YM4 allele) significantly reduced the average percentage of diseased spikelets (PDS) by 24.73% and 14.56%, respectively. The dwarfing allele of QPh.yas-5A was derived from Funo. Furthermore, we preliminary analyzed the genes within the physical interval of QPh.yas-5A using the reference genome information of wheat version 2.1. A total of 146 high-confidence annotated genes were detected in the target interval, which were mainly involved in the synthesis of cytochrome P450, dehydration response element-binding protein, ethylene response transcription factor, transcription factor MYC2, and cell wall receptor-associated kinases. The SNP marker closely linked to QPh.yas-5A was further converted into kompetitive allele-specific PCR marker KASP-5A, and its effect on plant height and FHB resistance was then verified in 126 wheat cultivars (lines). The results of this study could provide a solid foundation for future fine mapping QPh.yas-5A.

      Function analysis of different Cas9 promoters on the efficiency of CRISPR/ Cas9 system in soybean
      NIU Zhi-Yuan, QIN Chao, LIU Jun, WANG Hai-Ze, LI Hong-Yu
      Acta Agronomica Sinica. 2023, 49(12):  3227-3238.  doi:10.3724/SP.J.1006.2023.24285
      Abstract ( 212 )   HTML ( 18 )   PDF (8408KB) ( 129 )   Save
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      The CRISPR/Cas9 system has been widely used in plants and animals as an efficient gene editing system. Several Cas9 promoters, such as RPS5A and YAO, have been reported to improve the efficiency of gene editing in CRISPR/Cas9 system. In soybean, the influence of different Cas9 promoters on the efficiency of the CRISPR/Cas9 gene-editing system has not been elucidated. In this study, six efficient promoters with known functions (p35S, pGmRPS5Ab, pGmRPS5Ac, pAtRPS5A, pGmYAO, and pZmUbiquitin) and one endogenous soybean promoter with unknown function (pGmHE) were selected to construct the CRISPR/Cas9 knockout vectors. The editing efficiency of the Cas9 promoters on the endogenous soybean genes GmSPA1a and GmEID1 was tested by Agrobacterium tumefaciens mediated hair roots system, which indicated that soybean endogenous promoter pGmRPS5Ab had the highest editing efficiency. The editing efficiency of pAtRPS5A, p35S, and pZmUbiquitin were higher than that of pGmYAO and pGmRPS5Ac. Further analysis of the sequencing maps of target sites showed that the high peak maps accounted for 64.0% and 58.6% in the sequencing maps of pGmRPS5Ab and pAtRPS5A promoters, respectively, while in the sequencing maps of p35S-driven hair roots, the low peak accounted for a higher proportion (63.3%). These above results indicated that pGmRP5SAb and pAtRPS5A promoters not only had high editing efficiency, but also had better editing effect, and were more conducive to the isolation of homozygous mutants in the next generation. In conclusion, this study provide the reference for the construction of efficient soybean CRISPR/Cas9 vectors and help to improve the efficiency of soybean gene editing.

      Relative expression profile of the related genes with carotenoids metabolism in sweetpotato (Ipomoea batatas) based on RNA-seq data
      ZHAO Dong-Lan, ZHAO Ling-Xiao, LIU Yang, ZHANG An, DAI Xi-Bin, ZHOU Zhi-Lin, CAO Qing-He
      Acta Agronomica Sinica. 2023, 49(12):  3239-3249.  doi:10.3724/SP.J.1006.2023.24256
      Abstract ( 159 )   HTML ( 14 )   PDF (4784KB) ( 96 )   Save
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      The objective of this study is to explore the molecular mechanism of carotenoid metabolism and color mutation of sweetpotato and to study the carotenoid metabolism related genes by RNA-seq technology. Zheshu 81 and its mutant line with color mutation in root skin (from red to yellow) and leaf vein base (from purple to green) were used as the experimental materials. Bioinformatics analysis showed that the carotenoid biosynthesis (ko00906) pathway was significantly enriched in root skin and leaf vein base. The 24 differentially expressed genes (DEGs) and 10 DEGs in the ko00906 were screened from root skin and vein base, among which four were screened in both two parts, respectively. In the upstream pathway of carotenoid anabolism, compared with Zheshu 81, the geranylgeranyl pyrophosphate synthase gene GGDPS (g29773, g38646), lycopene synthase gene PSY (g11630) and ζ-carotene isomerase gene Z-ISO (g42608) were significantly up-regulated in mutant line, and GGDPS (g29773) was only expressed in mutant lines. DEGs were not screened in the upstream metabolic pathway of carotenoids in vein base. After the branching point of lycopene cyclization, two β-carotene hydroxylase genes CHYB (g33351, g953) were screened in root skin, one up-regulated and the other down-regulated. Two zeaxanthin epoxidase gene ZEP (g41700, g1103) were detected in root skin and vein base, respectively. And g41700 in root skin was significantly down-regulated, and g1103 in vein base was significantly up-regulated. In carotenoid catabolism, CCD8 (g21348), a carotenoid cleavage dioxygenase gene, was significantly up-regulated in root skin of mutant line. Two 9-cis epoxide carotenoid oxygenase genes NCED (g30636, g43412) were down-regulated in root skin and vein base of the mutant line. In addition, ten xanthoxin dehydrogenase ABA2 genes were detected in root skin and vein base, and nine of them were up-regulated. The relative expression levels of some genes by qRT-PCR were highly consistent with those of RNA-seq data. This study provides an important reference for the molecular mechanism of carotenoid metabolism and the analysis of different color mutations in root skin and vein base of sweetpotato.

      Transcriptomic profile of key stages of sex differentiation in cassava flowers and discovery of candidate genes related to female flower differentiation
      CHEN Hui-Xian, LIANG Zhen-Hua, HUANG Zhen-Ling, WEI Wan-Ling, ZHANG Xiu-Fen, YANG Hai-Xia, LI Heng-Rui, HE Wen, LI Tian-Yuan, LAN Xiu, RUAN Li-Xia, CAI Zhao-Qin, NONG Jun-Xin
      Acta Agronomica Sinica. 2023, 49(12):  3250-3260.  doi:10.3724/SP.J.1006.2023.34002
      Abstract ( 139 )   HTML ( 4 )   PDF (3178KB) ( 71 )   Save
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      To solve the breeding problem of the serious shortage of female cassava flowers, cassava variety ‘Xinxianxuan 048’ was used as the experimental material. Transcriptional sequencing technology was used to analyze the biological information of differentially expressed genes in female and male flowers during the critical period of cassava flower sex differentiation, explore the functions of differentially expressed genes and possible regulatory pathways involved, excavate candidate genes related to female differentiation, and verify the sequencing results by qRT-PCR method. The results showed that: There were 545 differentially expressed genes between male and female cassava flowers at the critical stage of gender differentiation. Among them, 48.63% of the differential genes were enriched in GO pathway of floral organ morphogenesis and development, and the genes enriched in plant phenylpropanol biosynthesis and plant hormone signal transduction were the most. AGL11, YABBY4, CRC, SUP, and other flower sex differentiation genes were significantly up-regulated in female flowers. Four genes of the cytokinin signaling pathway, including HK4, HPt4, ARR8, and ARR12, were significantly up-regulated in female flowers, while IAA14, GH3, SAUR22, and SAURR20, the early auxin response genes, were significantly down-regulated in female flowers. Therefore, the sexual differentiation of cassava flowers mainly involved the biological pathways of pollen, gametophyte, floral organ morphogenesis and development, and two metabolic pathways of plant phenylpropanoid biosynthesis and plant hormone signal transduction. Cytokinin and auxin might be the main hormones in cassava female flower differentiation. AGL11, YABBY4, CRC, SUP, HK4, HPt4, ARR8, and ARR12 may be positive regulators of cassava female flower differentiation.

      Mining maize flowering traits related candidate genes based on GWAS and WGCNA data
      QIAN Fu, ZHANG Zhan-Qin, CHEN Shu-Bin, DING Yong-Fu, SANG Zhi-Qin, LI Wei-Hua
      Acta Agronomica Sinica. 2023, 49(12):  3261-3276.  doi:10.3724/SP.J.1006.2023.33010
      Abstract ( 271 )   HTML ( 17 )   PDF (1510KB) ( 286 )   Save
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      The flowering time is one of the important traits in maize. It is of great significance to analyze the genetic basis and to mine the key core genes in flowering for maize varieties with wide adaptability. A natural population consisting of 580 maize inbred lines were planted for three years, to determine the three flowering traits (including days to anthesis, days to silking, and anthesis silking interval). Genome-wide association analysis was conducted using 31,826 SNPs distributed throughout the whole genome. Combined with transcriptome data of 14 different developmental stages of inbred line B73, weighted gene co-expression network analysis was performed to select tissue specific modules and key genes related to maize flowering time. A total of 14 SNPs for four flower traits under multiple environments and 10 potential candidate genes were mined by GWAS, WGCNA was used to mine 17 potential candidate genes in flowering time, three candidate genes were jointly mined by both approaches. Zm00001d052180 encodes a MADS box transcription factor 19, Zm00001d016814 encodes the NAC transcription factor 133, Zm00001d048082 encodes MADS box transcription factor 8, mainly involved in regulating inflorescence growth and development, which has certain research value and significance. These results provide a reference for the genetic basis and molecular mechanisms of flowering time related traits in maize.

      Genome-wide association study for amino acid content at R6 stage in soybean (Glycine max L.) seed
      ZHANG Hong-Mei, XIONG Ya-Wen, XU Wen-Jing, ZHANG Wei, WANG Qiong, LIU Xiao-Qing, LIU Hui, CUI Xiao-Yan, CHEN Xin, CHEN Hua-Tao
      Acta Agronomica Sinica. 2023, 49(12):  3277-3288.  doi:10.3724/SP.J.1006.2023.34031
      Abstract ( 156 )   HTML ( 6 )   PDF (7950KB) ( 102 )   Save
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      In order to analyze the genetic mechanism of amino acid content in soybean seeds at R6 stage, the contents of arginine, alanine, glutamic acid, and aspartic acid related to flavor quality of vegetable soybean were determined using 264 soybean germplasm materials in 2020 and 2021, and genome-wide association analysis (GWAS) was performed. The results showed that a total of 89 SNP loci were significantly associated with the contents of four amino acids at R6 stage in soybean in two years, among which 5 SNPs [S03_40647948 (Chr. 3), S05_2727464 (Chr. 5), S10_4122977 (Chr. 10), S17_34559022 (Chr. 17), and S19_48541685 (Chr. 19)] could be repeatedly detected by two years or two traits, respectively, which explained 11.25%-28.19% of phenotypic variation. The SNP marker S17_34559022 on Chr. 17 was significantly associated with glutamic acid content in different environments, which belonged to a stable genetic locus. A total of 9 candidate genes were excavated, including bHLH (bHLH DNA-binding superfamily protein), auxin-responsive protein family, and aspartyl protease family protein, it may be an important gene that affected amino acid content. In this study, 5 amino acid content dominant SNP sites and 9 candidate genes were excavated, which provided an insight into the genetic basis of amino acid content in soybean seed at R6 stage and laid a foundation for further mechanism exploration and breeding for flavor quality of vegetable soybean.

      Cloning and characterization of IbMAPKK9 gene associated with Fusarium oxysporum f. sp. batatas in sweet potato
      JING Xiao-Jing, YANG Xin-Sun, JIN Xiao-Jie, LIU Yi, LEI Jian, WANG Lian-Jun, CHAI Sha-Sha, ZHANG Wen-Ying, JIAO Chun-Hai
      Acta Agronomica Sinica. 2023, 49(12):  3289-3301.  doi:10.3724/SP.J.1006.2023.24284
      Abstract ( 115 )   HTML ( 5 )   PDF (21525KB) ( 55 )   Save
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      Mitogen-activated protein kinase (MAPK) cascades are important signaling modules in all organisms, which widely exist in plants. Mitogen-activated protein kinase kinase (MAPKKs) are located in the middle of the cascade reaction pathway and play the key roles in signal divergence. The disease resistance gene IbMAPKK9 was screened and cloned based on transcriptome data in sweetpotato, which contained a 987 bp open reading frame, encoding 328 amino acids and 1 domain (PF00069). Its protein mainly consisted of α-helixes and random coils. Multiple hormones (methyl jasmonate, ethylene, abscisic acid, gibberellin, and salicylic acid) and stress-related response elements were detected in the promoter region. Homologous protein comparison showed that IbMAPKK9 was closely related to ItMAPKK9-like (XP_031110493.1), InMAPKK9-like (XP_019189439.1), SlMAPKK9 (NP_001234595.1), and StMAPKK9 (XP_006363984.1). Besides, IbMAPKK9 gene encoded nuclear localization protein. The relative expression levels revealed that IbMAPKK9 was expressed in roots, stems, leaves, and petioles in response to Fusarium oxysporum f. sp batatas (Fob) infection. Transient expression analysis showed that IbMAPKK9 induced up-regulation of 5 genes related to salicylic acid synthesis pathway and signal transduction pathway within 48 hours, suggesting that IbMAPKK9 affected plant resistance by mediating salicylic acid signal pathway. This study can provide a theoretical basis for further analysis of the biological function of IbMAPKK9.

      Identification and relative expression profile of HIPPs gene family cadmium stress in sugar beet
      ZHAO Xiao-Xin, HUANG Shuo-Qi, TAN Wen-Bo, XING Wang, LIU Da-Li
      Acta Agronomica Sinica. 2023, 49(12):  3302-3314.  doi:10.3724/SP.J.1006.2023.34010
      Abstract ( 159 )   HTML ( 12 )   PDF (2741KB) ( 133 )   Save
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      Cadmium (Cd) ion balance and detoxification regulation are the cores of exploring cadmium tolerance mechanism in sugar beet, and the basis of heavy metal bioremediation using sugar beet. Heavy metal-associated isoprene plant proteins (HIPPs) are a class of multifunctional metal chaperone proteins, which may play a key role in absorption, transport, and compartmentalization of Cd ions. In the transcriptome expression profile of sugar beet responding to cadmium stress, BvHIPPs were found to be differentially expressed. Based on the above results, the whole BvHIPPs gene family members in beet genome was identified by bioinformatics method, and their physicochemical properties, evolutionary relationships, gene structure, cis-acting elements, chromosome localization, transcription, and expression characteristics under cadmium stress were analyzed. The results showed that there were 23 BvHIPPs family members in the beet genome, all of which contained HMA domains and isoprenylation motif, and 16 BvHIPPs were predicted to be located in the nucleus. According to cis-acting element analysis, beet BvHIPPs can participate in a variety of biological and abiotic stress responses. Transcriptomic analysis showed that all 23 BvHIPPs differentially participated in sugar beet in response to Cd, and qRT-PCR analysis verified furtherly the regulatory characteristics of the BvHIPPs correlated with Cd response. BvHIPPs might play an essential role in the adaptation of sugar beet to cadmium stress. The results suggest that BvHIPPs may play an important role in the process of beet adaptation to cadmium stress, and the results will lay a foundation for the molecular mechanism of beet bioremediation in heavy metal pollution.

      TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY
      Comparative study on the processing quality of winter rape in different ecological zones of the Yangtze River valley
      NING Ning, MO Jiao, HU Bing, LI Da-Shuang, LOU Hong-Xiang, WANG Chun-Yun, BAI Chen-Yang, KUAI Jie, WANG Bo, WANG Jing, XU Zheng-Hua, LI Xiao-Hua, JIA Cai-Hua, ZHOU Guang-Sheng
      Acta Agronomica Sinica. 2023, 49(12):  3315-3327.  doi:10.3724/SP.J.1006.2023.34017
      Abstract ( 181 )   HTML ( 17 )   PDF (739KB) ( 235 )   Save
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      Six rapeseed cultivars were chosen from three regions, including the upper, middle, and lower Yangtze River valley, and planted in Sichuan, Hubei, and Zhejiang experimental sites using the similar cultivation measures. The rapeseed was harvested at maturity stage, followed by cold pressing and the composition of unsaturated fatty acids (USFAs) and the content of chlorophyll, the total polar phenols, phytosterols, and tocopherols of rapeseed oil were assessed. Moreover, the essential properties of rapeseed oil on each experimental site were refined. The results showed that there were significant differences between the experimental sites in terms of the oil content and oil extraction efficiency of rapeseed, the chlorophyll, the total polar phenols, phytosterols, and tocopherol content of rapeseed oil. The results showed that: (1) Sichuan had a higher oil content than Hubei, whereas Zhejiang had the lowest oil content. The varieties from the middle and lower reaches of the Yangtze River were planted in Sichuan and their oil content increased, meanwhile Zhejiang had the highest seed oil extraction efficiency followed by Sichuan and Hubei. (2) The oleic acid content of rapeseed oil was the highest in Sichuan, followed by Zhejiang and Hubei; whereas the higher linoleic and linolenic acid contents were noted at the Hubei experimental site. Moreover, the total polar phenols and phytosterol content of rapeseed oil was the highest in the Sichuan followed by Hubei and Zhejiang; contrarily, the tocopherol content and color of rapeseed oil were best in the Zhejiang followed by Hubei and Sichuan. (3) Rapeseed oil's antioxidant capacity significantly varied between sites, which was the highest in Sichuan, followed by the Hubei and Zhejiang. The lower temperature and rainfall during rapeseed pod maturity period contributed to the stronger antioxidant capacity of studied cultivars in Sichuan site. Conclusively, the rapeseed oil quality was varied at different experimental sites in the Yangtze River valley. Thus, the findings of the current study can be used as a reference when choosing high-quality rapeseed varieties in different ecological zones.

      Establishment of critical nitrogen concentration model and nitrogen nutrient diagnosis for summer maize (Zea mays L.) leaves at vegetative growth stage under different phosphorus and potassium application rates
      LIU Dong, ZHANG Chuan, REN Hao, WANG Hong-Zhang, ZHAO Bin, ZHANG Ji-Wang, REN Bai-Zhao, ZHANG Yong-Li, LIU Peng
      Acta Agronomica Sinica. 2023, 49(12):  3328-3341.  doi:10.3724/SP.J.1006.2023.23075
      Abstract ( 172 )   HTML ( 10 )   PDF (1211KB) ( 263 )   Save
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      The experiments were carried out on the long-term positioning experiment platform of Dongping Agricultural Research Institute since 2010. The split-plot experimental design was used with different P2O5 input in the main plots and different K2O input in the sub-plot and different N input in the sub-sub plots. The P2O5 values were 0, 90, 120, and 150 kg hm-2, which were represented as P0, P1, P2, and P3, respectively. The K2O was 0, 180, 240, and 300 kg hm-2, expressed in terms of K0, K1, K2, and K3, respectively. The N was 0, 180, 240, and 300 kg hm-2, denoted as N0, N1, N2, and N3, respectively. From 2020 to 2021, Denghai 605 was used as the experimental material to deeply analyze the effect of nutrient application rate on dry matter and nitrogen concentration of summer maize leaves, aimed to build a critical nitrogen dilution curve for the nutrient growth stage of summer maize leaves, and explore the feasibility of diagnosing and evaluating nitrogen nutrition status of summer maize with nitrogen nutrition index model under different fertilizer application rates. The results showed that the dry matter and nitrogen concentration of summer maize leaves prior anthesis increased with the increment of nitrogen, phosphorus, and potassium fertilizer application. The nitrogen concentration in leaves decreased with the growth process and the accumulation of leaves dry matter, showing a dilution phenomenon. The variations of leaves dry matter and nitrogen concentration could be divided into two groups: nitrogen limitation and non-nitrogen limitation. Further, the curve model of critical nitrogen concentration at the vegetative growth stage of summer maize leaves under different phosphorus and potassium levels was constructed: NLC0 = 2.745 LDM-0.529, NLC1 = 3.245 LDM-0.334, NLC2 = 3.557 LDM-0.290, NLC3 = 3.639 LDM-0.286. Nitrogen nutrition index was calculated based on the critical nitrogen concentration dilution curve, which was highly significantly related to the relative leaves dry matter and the relative grain yield. Combining the linear plus platform relationship between nitrogen nutrition index and the relative leaves dry and the relative grain yield, the crop nitrogen status could be well evaluated under the conditions of nitrogen limitation and non-nitrogen limitation. Therefore, the critical nitrogen concentration and nitrogen index at vegetative growth stage of summer maize can effectively predict the critical nitrogen concentration and characterize the nitrogen nutrient status of summer maize.

      Effects of application nitrogen on carbon and nitrogen metabolism of summer maize grain under post-silking heat stress
      WANG Rui, LI Xiang-Ling, GUO Dong, WANG Xin-Bing, MA Wei, LI Cong-Feng, ZHAO Ming, ZHOU Bao-Yuan
      Acta Agronomica Sinica. 2023, 49(12):  3342-3351.  doi:10.3724/SP.J.1006.2023.33003
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      Post-silking heat stress is one of the main stresses affecting grain filling and yield formation of summer maize in the Huang-Huai-Hai plains. At present, it has been confirmed that increasing nitrogen application can alleviate the inhibition of post-silking heat stress on the yield formation of wheat, maize, and rice, but the regulatory pathways and physiological mechanisms remain unclear. In this study, two maize varieties Zhengdan 958 (ZD958) and Xianyu 335 (XY335) were selected in pot experiment. To study the effects of increased nitrogen application on carbon and nitrogen metabolism of maize under heat stress during post-silking stage, two temperature treatments [ambient temperature (CK) and heat stress (HS)], three nitrogen application levels [low nitrogen application rate (LN): 120 kg hm-2, middle nitrogen application rate (MN): 240 kg hm-2, and high nitrogen application rate (HN): 360 kg hm-2] were set. The results showed that the dry weight of ZD958 and XY335 cultivars at maturity stage decreased by 10.6%-19.3% after 20 days of post-silking heat stress (35oC) compared with the ambient temperature. However, the decrease of kernel dry weight under heat stress was gradually decreased with the increase of nitrogen application rate, and the decrease rate (10.6%-11.2%) of kernel dry weight under medium nitrogen application rate (MN) and high nitrogen application rate (HN) was lower than that (16.2%-19.3%) under low nitrogen application rate (LN), which indicating that increased nitrogen application could significantly increase maize kernel dry weight under post-silking heat stress. This was mainly due to the increasing application of nitrogen effectively alleviated the inhibitory effect of early post-silking heat stress on maize grain nitrogen metabolism, and significantly increased the activities of key enzymes of nitrogen metabolism such as glutamine synthetase (GS) and glutamate synthetase (GOGAT). At the same time, the activities of sucrose phosphate synthetase (SPS) and sucrose synthetase (SS), which were key enzymes of carbon metabolism, were maintained, and the synthesis of soluble sugar in grains was increased, thus ensuring a larger amount of material for grain filling. In conclusion, increasing nitrogen application can alleviate the inhibition of post-silking heat stress on grain carbon and nitrogen metabolism and promote the accumulation of assimilates in grain and increase the kernel weight and yield, which provides a way for the resistant cultivation of summer maize in the Huang-Huai-Hai plains.

      Spatio-temporal characteristics of water requirement of main crops in Xinjiang from 1960 to 2020
      HE Xu-Gang, MAMAT Sawut, XIA Zi-Yang, SHI Jun-Yin, HE Xiao-Ning, SHENG Yan-Fang, LI Rong-Peng
      Acta Agronomica Sinica. 2023, 49(12):  3352-3363.  doi:10.3724/SP.J.1006.2023.31007
      Abstract ( 185 )   HTML ( 6 )   PDF (4372KB) ( 156 )   Save
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      Spatio-temporal analysis of crop water requirement and crop irrigation water requirement is crucial to the optimal allocation of water resources and the formulation of irrigation systems. The objective of this study is to understand the spatio-temporal characteristics and influencing factors of the water requirement during the growth period and irrigation water requirement of the main crops in Xinjiang, cotton, spring wheat, winter wheat, and corn. Based on the daily meteorological observation data from 1960 to 2020, the Penman-Monteith formula and the single crop coefficient method were adopted in this study, and Mann-Kendall (TFPW-MK) of Detrended Preset White (TFPW) was used to study the changing characteristics of water requirement of four crops. The temporal and spatial evolution trend of crop water requirement and irrigation water requirement were predicted by rescaled range (R/S) analysis. Using the principle of important covariate feature identification of the random forest model, the importance ranking of meteorological factors and crop water requirement was analyzed, and the causes of changes in crop water requirement were explored. The results show that: 1) the water requirement of major crops in Xinjiang had generally shown a trend of “increase first, then decrease and then increase” for 61 year. The order of crop water demand and irrigation water requirement from large to small was: cotton > corn > winter wheat > spring wheat. In terms of space, there was a spatial distribution of “Southern Xinjiang>Northern Xinjiang, Southeast>Northwest, East>Western”. The variation range of water requirement for major crops was: cotton 381.20-991.20 mm (mean 654.94 mm), corn 350.26-924.48 mm (mean 607.98 mm), spring wheat 361.96-709.69 mm (average 464.89 mm), winter wheat 266.47-753.62 mm (average 495.7 0 mm). The range of irrigation water requirement was: cotton 49.49-975.88 mm (average 563.19 mm), corn 52.47-910.85 mm (average 530.18 mm), spring wheat 42.58-701.29 mm (average 409.28 mm), winter wheat 21.94-741.77 mm (average 418.26 mm). Since the middle and late 1980s, irrigation water requirement decreased more than water requirement. 2) According to the TFPW-MK analysis, in the past 61 years, the water requirement of 12 stations mainly distributed in the northern edge of the Tarim Basin, including Shaya and Aksu, and Baekol in the eastern Xinjiang, showed an upward trend. The water requirement of 27 stations in Karamay in Xinjiang and Artux in southern Xinjiang gradually decreased; the rest of the stations fluctuated up and down. 3) In the prediction of future water demand using the R/S method, four crop water demand and irrigation water demand at Tacheng, Toli, Fuyun and Urumqi stations in northern Xinjiang, Baekol in eastern Xinjiang, and Shaya, Wuqia, Tazhong, Qiemo and Kalpin stations in southern Xinjiang will decrease in the future, while spring and winter wheat water demand at Hongliuhe, Baekol and Bayanbulak in eastern Xinjiang will show an increasing trend in the future. 4) During the crop growth period, wind speed and temperature were the most important factors affecting the water requirement of major crops in Xinjiang, while precipitation was the least important factor for the water requirement of major crops in Xinjiang. This research comprehensively provides decision-making and basis for the formulation of high-efficiency agricultural water use and irrigation measures in Xinjiang.

      Comparing different machine learning methods for maize leaf area index (LAI) prediction using multispectral image from unmanned aerial vehicle (UAV)
      MA Jun-Wei, CHEN Peng-Fei, SUN Yi, GU Jian, WANG Li-Juan
      Acta Agronomica Sinica. 2023, 49(12):  3364-3376.  doi:10.3724/SP.J.1006.2023.33001
      Abstract ( 153 )   HTML ( 5 )   PDF (4801KB) ( 136 )   Save
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      To make an accurate estimation of leaf are index (LAI) based on machine learning methods and images from UAV, we compared the several mainstream machine learning methods for maize LAI prediction, such as Artificial Neural Network method (ANN), Gaussian Process Regression method (GPR), Support Vector Regression method (SVR), and Gradient Boosting Decision Tree (GBDT). For this purpose, field experiments that considering apply of different amount of organic fertilizer, different amount of inorganic fertilizer, different amount of crop residue, and different planting density were carried out. Based on these experiments, field campaign were conducted to obtain UAV multispectral images and LAI data at different growth stages in maize. Based on above data, firstly, correlation analysis was used to select LAI-sensitive spectral indices, and then the Partial Least Squares Regression method (PLSR) and ANN, GPR, SVR, GBDT were coupled to design the LAI prediction models, respectively, and their performance for LAI prediction were compared. The results showed that the LAI prediction model constructed by PLSR+GBDT method had the highest accuracy and the best stability. The models of R2 and RMSE values were 0.90 and 0.25, and the verified R2 and RMSE values were 0.90 and 0.29 during validation, respectively. The model based on PLSR+GPR model was followed, with R2 and RMSE values of 0.86 and 0.30 during calibration, and R2 and RMSE values of 0.89 and 0.29 during validation, respectively. Besides, it had faster training speed and could give the uncertainty of the prediction. The model designed by PLSR+ANN method had R2 and RMSE values of 0.85 and 0.31 during calibration, and R2 and RMSE values of 0.89 and 0.30 during validation, respectively. The model designed by PLSR+SVR method had R2 and RMSE values of 0.86 and 0.32, and R2 and RMSE values of 0.90 and 0.33, respectively. Therefore, PLSR+GBDT method and PLSR+GPR method are recommended as the optimal methods for designing maize LAI prediction models.

      Characteristics of respiratory metabolism in growth and development of sugar beet taproot
      YU Chao, LI Guo-Long, SUN Ya-Qing, LI Ning-Ning, ZHANG Shao-Ying
      Acta Agronomica Sinica. 2023, 49(12):  3377-3386.  doi:10.3724/SP.J.1006.2023.34026
      Abstract ( 134 )   HTML ( 5 )   PDF (1132KB) ( 125 )   Save
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      Respiration is an important metabolic basis for plant growth and development. The objective of this study is to compare the differences of taproot development characteristics, respiratory rate, respiratory key enzyme activity, gene expression, and energy change in different growth stages, and analyze the relationship between various respiratory physiological and sugar accumulation of sugar beet roots. In this study, four different genotypes of sugarbeet varieties were used as the experimental materials. The key enzyme activity and gene expression of respiratory metabolic pathway were determined, and respiratory pathway inhibitors were used at different growth stages. These results indicated the EMP-TCA was the main respiratory metabolic pathway during the growth process in beet taproot. No matter which respiratory pathway was inhibited, the weight and diameter of beet taproot can be reduced. Different respiratory metabolic pathways (EMP, TCA, and PPP) all played the important roles in promoting taproot expansion. In conclusions, this study laid a theoretical foundation for further research on the physiological mechanism of sugarbeet taproot, and provided physiological indicators for the breeding and identifying high-yield sugarbeet.

      RESEARCH NOTES
      Cloning and functional analysis of maize ZmMYC2 gene
      DU Ming, CHEN Ming-Chao, FANG Yu, WU Jian-Dong
      Acta Agronomica Sinica. 2023, 49(12):  3387-3398.  doi:10.3724/SP.J.1006.2023.23081
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      Plants are often harmed by pathogens during their growth and development, which seriously affect crop yield. MYC2 belongs to the bHLH family of transcription factors and plays an important role in the regulation of JA-mediated signaling pathways. In the previous work, maize gene ZmMYC2 which was homologous to Arabidopsis thaliana was detected through the analysis of the MYC family evolutionary tree. In this study, we cloned ZmMYC2, which had a total length of 2118 bp and encoded 705 amino acid residues. The encoded protein was localized in the nucleus. RT-qPCR analysis showed that ZmMYC2 was expressed in all tissues of maize, but the relative expression level was the highest in leaves. The results showed that ZmMYC2 could be induced by jasmonic acid (jasmonic acid, JA), salicylic acid (salicylic acid, SA), and ethylene (ethylene, ETH). In 50 μmol L-1 JA medium, root length of overexpressed Arabidopsis thaliana was significantly shorter than wild type, and that of mutant Arabidopsis thaliana was significantly longer than wild type. There was no significant difference in root length between Arabidopsis thaliana and wild type. Pst DC3000 (Psedumonas syrinage pv.tomato DC3000, Pst DC3000) was inoculated with ZmMYC2 Arabidopsis materials, and the wild type, mutant, and complement Arabidopsis showed better state relative to over expression. It was speculated that ZmMYC2 decreased the defense ability of Arabidopsis thaliana against pathogen. Before inoculation, the dead area of leaves and the amount of bacteria in leaves with the overexpression of Arabidopsis thaliana were reduced by exogenous JA hormone. JA hormone enhanced the resistance of ZmMYC2 to pathogens. Subcellular localization showed that ZmMYC2 was a nuclear localization protein. The yeast two-hybrid showed that ZmMYC2 could interact with JAZ1 and JAZ3 in JAZ protein. The relative expression levels of JA, SA, defense genes, and programmed cell death genes showed that ZmMYC2 negatively regulated the relative expression level of PDF1.2, and positively regulated the relative expression level of PR1, MED25, COI1, and programmed cell death gene HIN1. In conclusion, ZmMYC2 was involved in JA signal transduction by interacting with JAZ1 and JAZ3, which reduced the defense ability of Arabidopsis thaliana against pathogen stress.

      Physiological characteristics and genetic research of rolled leaf mutant1 (RL1) in wheat (Triticum aestivum L.)
      LIU Ye, LI Yue, YUAN Ming-Yang, WEI Nai-Cui, GUAN Pan-Feng, ZHAO Jia-Jia, WU Bang-Bang, ZHENG Xing-Wei, HAO Yu-Qiong, QIAO Ling, ZHENG Jun
      Acta Agronomica Sinica. 2023, 49(12):  3399-3410.  doi:10.3724/SP.J.1006.2023.31004
      Abstract ( 179 )   HTML ( 17 )   PDF (7839KB) ( 106 )   Save
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      Wheat leaves tend to fold or curl when exposure to stresses, the dehydration avoidance in morphology can reduce the damage of abiotic stress. At present, the physiological and genetic regulation mechanism associated with leaf curling is not clear in wheat. This study reported a novel rolled leaf mutant (RL1) from the ethyl methyl sulphonate (EMS) mutagenesis cultivar Jinmai 47. The leaves of the mutant RL1 were curled during the growth period, and the primary leaves were slightly curled along axial vein to paraxial plane. Leaf curling was accelerated with the growth until the leaf was tubular. Compared to wild type (WT), plant height, ear length, flag leaf narrowing, and 1000-grain weight were decreased in mutant RL1. Triphenyltetrazolium Chloride (TTC) staining showed that seed vigor of RL1 was low, together with the decreased germination rate by 22%. Additionally, there was no significant differences in chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance, and intercellular CO2 concentration between RL1 and WT, while water utilization rate was decreased in RL1 after heading for 10 days. Low temperature, high temperature, and drought led to the leaf rolling in RL1. RL1 showed fewer leaf/lobular veins via paraffin section assay, and the number of abaxial sclerenchyma and adaxial parenchyma cells were reduced in midrib region of RL1. Moreover, the area and counts of vesicular cells between the vascular bundles were significantly reduced in RL1, together with the vesicular cells at the midvein region of leaves compared with WT. Vesicular cells and vascular bundles shrunk and decreased, respectively, resulting in the situation that the entire blade was extremely crimped to the adaxial plane. Genetic analysis demonstrated that the mutant trait was localized on the short arm of chromosome 1D, regulated by a pair of nuclear genes with incomplete dominance and fine mapping analysis further locked the target interval at 9.42 Mb.

Co-sponsored:
the Crop Science Society of China
the Institute of Crop Science, CAAS
China Science Publishing & Media Ltd.
Published: Science Press
Editor-in-chief: Wan Jian-min
Associate Editors-in-Chief:
Chen Xiao-ya Yang Jian-chang Zhang Xian-long Wang Jian-kang Xu Ming-liang Liu Chun-ming Wang Dao-wen Sun Chuan-qing Ding Yan-feng Jin Wei-wei Chu Cheng-cai Cheng Wei-hong
Director of the editorial department:
Yan Chun-ling
CN 11-1809/S
ISSN 0496-3490
Post subscription code: 82-336

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  • Started in 2013
  • Covered by SCIE
  • Open access in ScienceDirect

Editor in chief: Wan Jian-min
CN 10-1112/S
ISSN 2095-5421, 2214-5141(online)
Online published:
https://www.sciencedirect.com/journal/the-crop-journal
Submission: https://www.editorialmanager.com/cj/
E-mail: cropjournal@caas.cn
Tel: 8610-82108548

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