摘要：
Peanut is an economically-important oilseed crop and needs a large amount of calcium for its normal growth and development. Calcium deficiency usually leads to embryo abortion and subsequent abnormal pod development. Different tolerance to calcium deficiency has been observed between different cultivars, especially between large and small-seed cultivars. In order to figure out different molecular mechanisms in defensive responses between two cultivars, we treated a sensitive (large-seed) and a tolerant (small-seed) cultivar with different calcium levels. The transcriptome analysis identified a total of 58 and 61 differentially expressed genes (DEGs) within small-seed and large-seed peanut groups under different calcium treatments, and these DEGs were entirely covered by gene modules obtained via weighted gene co-expression network analysis (WGCNA). KEGG enrichment analysis showed that the blue-module genes in the large-seed cultivar were mainly enriched in plant-pathogen attack, phenolic metabolism and MAPK signaling pathway, while the green-module genes in the small-seed cultivar were mainly enriched in lipid metabolism including glycerolipid and glycerophospholipid metabolisms. By integrating DEGs with WGCNA, a total of eight hub-DEGs were finally identified, suggesting that the large-seed cultivar concentrated more on plant defensive responses and antioxidant activities under calcium deficiency, while the small-seed cultivar mainly focused on maintaining membrane features to enable normal photosynthesis and signal transduction. The identified hub genes might give a clue for future gene validation and molecular breeding to improve peanut survivability under calcium deficiency.
作者机构：
[Xiao, Yinghui; Peng, Pei; Luo, Lihua; Jiang, Haoyu] Hunan Agr Univ, Coll Agron, Changsha 410128, Peoples R China.;[Ye, Changrong] Huazhi Biotech Co Ltd, Changsha 410125, Peoples R China.
通讯机构：
[Yinghui Xiao] C;College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
hybrid rice;blast resistance;marker-assisted selection;thermo-sensitive genic male sterile line;gene pyramiding
摘要：
Rice blast caused by pathogenic fungus Magnaporthe oryzae is one of the most serious diseases in rice. The pyramiding of effective resistance genes into rice varieties is a potential approach to reduce the damage of blast disease. In this study, combinations of three resistance genes, Pigm, Pi48 and Pi49, were introduced into a thermo-sensitive genic male sterile (PTGMS) line Chuang5S through marker-assisted selection. The results showed that the blast resistance of improved lines increased significantly compared with Chuang5S, and the three gene pyramiding lines (Pigm + Pi48 + Pi49) had higher rice blast resistance level than monogenic line and digenic lines (Pigm +Pi48, Pigm + Pi49). The genetic backgrounds of the improved lines were highly similar (>90%) to the recurrent parent Chuang5S by using the RICE10K SNP chip. In addition, agronomic traits evaluation also showed pyramiding lines with two or three genes similar to Chuang5S. The yields of the hybrids developed from improved PTGMS lines and Chuang5S are not significantly different. The newly developed PTGMS lines can be practically used for the breeding of parental lines and hybrid varieties with broad spectrum blast resistance.
通讯机构：
[Liu, ZQ ] ;South China Agr Univ, Coll Agr, Guangdong Prov Key Lab Plant Mol Breeding, Guangzhou 510642, Guangdong, Peoples R China.;South China Agr Univ, State Key Lab Conservat & Utilizat Subtrop Agrobio, Guangzhou 510642, Guangdong, Peoples R China.
摘要：
Understanding the evolutionary forces in speciation is a central goal in evolutionary biology. Asian cultivated rice has two subspecies, indica and japonica, but the underlying mechanism of the partial reproductive isolation between them remains obscure. Here we show a presence-absence variation (PAV) at the Se locus functions as an indica-japonica reproductive barrier by causing hybrid sterility (HS) in indica-japonica crosses. The locus comprises two adjacent genes: ORF3 encodes a sporophytic pollen killer, whereas ORF4 protects pollen in a gametophytic manner. In F-1 of indica-japonica crosses, pollen with the japonica haplotype, which lacks the sequence containing the protective ORF4, is aborted due to the pollen-killing effect of ORF3 from indica. Evolutionary analysis suggests ORF3 is a gene associated with the Asian cultivated rice species complex, and the PAV has contributed to the reproductive isolation between the two subspecies of Asian cultivated rice. Our analyses provide perspectives on rice inter-subspecies post-zygotic isolation, and will promote efforts to overcome reproductive barriers in indica-japonica hybrid rice breeding. The mechanisms of the partial reproductive isolation between the two subspecies of rice remains obscure. Here, the authors show that the two adjacent genes form a killer-protector system to induce hybrid male sterility and reproductive isolation between indica and japonica.
摘要：
As a most significant cereal crop, maize provides vital nutritional components to humans and livestock. Drought stress curtails maize growth and yield by impairing several morphological, physiological, and biochemical functions. The rising threats of drought stress significantly affect global food security and increase the ratio of hunger and starvation. The use of molecular breeding techniques has enabled maize researchers to deeply examine the genetic control of drought tolerance and the genetic differences between genotypes to drought stress. Despite the significant progress in molecular genetics, the drought tolerance mechanism is still not fully understood. With the advancements in molecular research, researchers have identified several molecular factors associated with maize tolerance to drought stress. Quantitative trait loci (QTL) mapping and genome-wide association study (GWAS) analysis have led to identifying QTL, and genes linked to drought tolerance in maize that can be further exploited for their possible breeding applications. Transcriptome and transcription factors (TFs) analysis has revealed the documentation of potential genes and protein groups that might be linked to drought tolerance and accelerate the drought breeding program. Genetic engineering has been used to develop transgenic maize cultivars that are resistant to drought stress. Clustered regularly interspaced short palindromic repeats (CRISPR/Cas9) is a new ray of hope to edit the gene of interest to enhance drought tolerance in maize and save both time and cost in cultivar development. In the current review article, we have tried to present an updated picture of the advancements of drought tolerance in maize and its future prospects. These organized pieces of information can assist future researchers in understanding the basis of drought tolerance to adopt a potential breeding tool for breeding drought-tolerant maize cultivars.
摘要：
Basic helix-loop-helices (bHLHs) are present in all eukaryotes and form one of the largest families of transcription factors (TFs) found in plants. bHLHs function as transcriptional activators and/or repressors of genes involved in key processes involved in plant growth and development in interaction with the environment (e.g., stomata and root hair development, iron homeostasis, and response to heat and shade). Recent studies have improved our understanding of the functioning of bHLH TFs in complex regulatory networks where a series of post-translational modifications (PTMs) have critical roles in regulating their subcellular localization, DNA-binding capacity, transcriptional activity, and/or stability (e.g., protein-protein interactions, phosphorylation, ubiquitination, and sumoylation). Further elucidating the function and regulation of bHLHs will help further understanding of the biology of plants in general and for the development of new tools for crop improvement.
摘要：
In recent years, the problem of Cd pollution in paddy fields has become more and more serious, which seriously threatens the safe production of food crops and human health. Using microorganisms to reduce cadmium pollution in rice fields is a green, safe and efficient method, the complicated interactions between the microbes in rice roots throughout the process of cadmium absorption by rice roots are poorly understood. In this investigation, a hydroponic pot experiment was used to examine the effects of bacteria R3 (Herbaspirillum sp) and T4 (Bacillus cereus) on cadmium uptake and the endophytic bacterial community in rice roots. The results showed that compared with CK (Uninoculated bacterial liquid), the two strains had significant inhibitory or promotive effects on cadmium uptake in rice plant, respectively. Among them, the decrease of cadmium content in rice plants by R3 strain reached 78.57-79.39%, and the increase of cadmium content in rice plants by T4 strain reached 140.49-158.19%. Further investigation showed that the cadmium content and root cadmium enrichment coefficient of rice plants were significantly negatively correlated with the relative abundances of Burkholderia and Acidovorax, and significantly positively correlated with the relative abundances of Achromobacter, Agromyces and Acidocella. Moreover, a more complex network of microbes in rice roots inhibited rice plants from absorbing cadmium. These results suggest that cadmium uptake by rice plants is closely related to the endophytic bacterial community of roots. This study provides a reference scheme for the safe production of crops in cadmium contaminated paddies and lays a solid theoretical foundation for subsequent field applications.
摘要：
Wheat production suffers greatly from drought stress, resulting in yield losses. Endophytes and rhizobacteria have been recognized as a valuable source in mitigating of drought stress by improving plant resistance and growth. In this review, we discuss how endophytes and rhizobacteria help wheat cope with drought stress. During drought stress, endophytes have been found to increase plant water usage efficiency and decrease water loss. Endophytes are harmless microorganisms that live inside plant tissues. Rhizobacteria establish colonies in the root system through various procedures, including phytohormones production, modification of root architecture, and activation of stress-inducible genes, thereby promoting plant growth and enhancing stress resistance. Numerous studies have shown how endophytes and rhizobacteria can improve the potential of wheat to withstand drought. For instance, inoculation with endophytes like Piriformospora indica and Bacillus spp. has been proven to enhance wheat plant yield and drought resistance. Similarly, it has been proven that rhizobacteria like Pseudomonas spp. and Azospirillum brasilense enhance drought tolerance through a variety of mechanisms. To minimize the consequence of wheat under drought conditions, the efficient method is the use of endophytes and rhizobacteria as biofertilizers, which could ultimately boost yields and sustainability. More research needs to be done so that it can be used most effectively in the field and so that we can better understand how they work. We explained current understanding of the role and mechanisms of endophytes and rhizobacteria in minimizing drought stress effects in wheat. Additionally, we highlighted areas of limited knowledge and suggested directions for future research. This review will provide the new suggestion on the role of endophytes and rhizobacteria in mitigating the drought stress in plants.
通讯机构：
[Guan, M ] H;Hunan Branch Natl Oilseed Crops Improvement Ctr, Changsha, Peoples R China.;Hunan Agr Univ, Coll Agr, Changsha, Peoples R China.;Southern Reg Collaborat Innovat Ctr Grain & Oil Cr, Changsha, Peoples R China.
摘要：
Cytoplasmic male sterile system (CMS) is one of the important methods for the utilization of heterosisin Brassica napus. The involvement of long non-coding RNAs (lncRNAs) in anther and pollen development in B.napus has been recognized, but there is little data on the involvement of lncRNAs in pollen abortion in different types of rapeseed CMS. The present study compared the cytological, physiological and biochemical characteristics of Nsa CMS (1258A) and Pol CMS (P5A) during pollen abortion, and high-throughput sequencing of flower buds of different sizes before and after pollen abortion. The results showed that insufficient energy supply was an important physiological basis for 1258A and P5A pollen abortion, and 1258A had excessive ROS (reactive oxygen species) accumulation in the stage of pollen abortion. Functional analysis showed that Starch and sucrose metabolism and Sulfur metabolism were significantly enriched before and after pollen abortion in 1258A and P5A, and a large number of genes were down-regulated. In 1258A, 227 lncRNAs had cis-targeting regulation, and 240 cis-target genes of the lncRNAs were identified. In P5A, 116 lncRNAs had cis-targeting regulation, and 101 cis-target genes of the lncRNAs were identified. There were five lncRNAs cis-target genes in 1258A and P5A during pollen abortion, and LOC106445716 encodes β-D-glucopyranosyl abscisate β-glucosidase and could regulate pollen abortion. Taken together, this study, provides a new perspective for lncRNAs to participate in the regulation of Nsa CMS and Pol CMS pollen abortion.
摘要：
Drought stress is a major abiotic factor restricting crop production. frequently suffers from drought stress as it is mainly planted in the harsh environments. Little research on the identification of drought-tolerant loci or genes of barley has been performed up to date. Here, we determined the phenotypic variation of drought tolerance in a barley population from the International Barley Core Selected Collection (BCS). Under drought stress, shoot water content showed the distinct difference among barley genotypes and the maximum consistency for a given genotype under the two planting conditions. Twenty significant SNPs (P < 10-3) and 41 candidate genes were identified by genome-wide association study (GWAS)on the examined barley accessions. Furthermore, transcriptomic analysis (RNA-Seq) identified 2030 and 1947 differentially expression genes (DEGs) in the leaves of a drought-sensitive genotype BCS8 and a tolerant genotype BS24, respectively, and they are mainly involved in water deficit processes in GO analysis and metabolic pathways in KEGG analysis. Finally, seven DEGs were confirmed by qRT-PCR as drought-responding genes, including WRKY, NPF and FLA.
The data sets supporting the results of this article are included within the article and its additional files. All the other data are available from the corresponding author upon request.
摘要：
Excessive nitrogen and insufficient calcium could significantly impact peanut yields. This study investigated the effects of nitrogen and calcium fertilizers on nutrient absorption, utilization, and yield; experiments were conducted using the peanut cultivar from Xianghua 2008 in a split-plot arrangement with two calcium fertilizer levels (Ca-0: 0 and Ca-1: 568 kg CaO ha(-1)) in the main plots and six nitrogen fertilizer gradients (N-0: 0, N-45.0: 45.0, N-90.0: 90.0, N-112.5: 112.5, N-135.0: 135.0, and N-157.5: 157.5 kg N ha(-1)) in subplots between 2015 and 2016 in Changsha, China. We examined the impact of different rates of calcium and nitrogen fertilizers on the net photosynthetic rate (Pn), agronomic traits, dry matter quality, yield and yield composition, nutrient accumulation, and distribution. The combined application of calcium and nitrogen fertilizers significantly affected the yield and yield components, Pn, main stem height, dry matter, and nutrient accumulation. Under the same calcium level, nitrogen application significantly increased the main stem height and Pn and promoted the accumulation of dry matter and nutrients in the plant, particularly in the kernel. Under the same nitrogen treatment, calcium significantly increased Pn and promoted the accumulation of dry matter, calcium, and magnesium. The pod yield increased gradually with an increasing nitrogen application rate (0-112.5 kg ha(-1)) and peaked at N-112.5, increasing by 52.3-138.0% compared with N-0. However, excessive nitrogen application (N > 112.5 kg ha(-1)) decreased the pod yield. Under different nitrogen fertilizer levels, calcium application increased pod yields by 11.5-29.6% by promoting Pn, nutrient uptake, accumulation in the individual plant, and nutrient accumulation in the kernel. Therefore, this study suggested that adjusting the calcium (568 kg ha(-1)) and nitrogen (112.5 kg ha(-1)) fertilizer rates significantly improved peanut growth and productivity by enhancing photosynthetic efficiency and nutrient accumulation in calcium-deficient acidic red soil.
摘要：
The members of the GRAS gene family play important roles in regulating plant growth and development, but their functions in regulating early plant maturity traits are still unknown. In this study, we used a series of bioinformatics tools to identify GRAS gene family members and investigate the function of the gene family (GhGRAS55) using a genome-wide database of upland cotton samples. A total of 58 members of the GRAS gene family were identified and screened, which were distributed on 21 chromosomes within the whole cotton genome. The results of the phylogenetic analysis showed that the genes of upland cotton, island cotton, African cotton, Raymond cotton, and Arabidopsis were distributed in subfamilies I-VIII, although subfamily II did not contain any upland cotton or Arabidopsis GRAS family members. The structures and other characteristics of the genes in this family were clarified using bioinformatics technology. The transcriptomic sequencing results for early and late maturing cotton species showed that the expression of most GRAS family genes, such as GhGRAS10, GhGRAS5511, and GhGRAS55, was lower in early maturing species than late maturing species. We also found that cotton plants with GhGRAS55 genes that were silenced by virus-induced gene silencing (VIGS) technology showed early bud emergence phenotypes, so it could be speculated that the GhGRAS55 gene has the function of regulating early maturity in cotton.
通讯机构：
[Yuzhu Zhang; Zhenxie Yi] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China
通讯机构：
[Wenbang Tang; Yunhua Xiao] A;Authors to whom correspondence should be addressed.<&wdkj&>Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Authors to whom correspondence should be addressed.<&wdkj&>Hunan Provincial Key Laboratory of Rice and Rapeseed Breeding for Disease Resistance, College of Agronomy, Hunan Agricultural University, Changsha 410128, China<&wdkj&>State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China
摘要：
Heat stress caused by rapidly changing climate warming has become a serious threat to crop growth worldwide. Exogenous cytokinin (CK) kinetin (KT) has been shown to have positive effects in improving salt and drought tolerance in plants. However, the mechanism of KT in heat tolerance in rice is poorly understood. Here, we found that exogenously adequate application of KT improved the heat stress tolerance of rice seedlings, with the best effect observed when the application concentration was 10(-9) M. In addition, exogenous application of 10(-9) M KT promoted the expression of CK-responsive OsRR genes, reduced membrane damage and reactive oxygen species (ROS) accumulation in rice, and increased the activity of antioxidant enzymes. Meanwhile, exogenous 10(-9) M KT treatment significantly enhanced the expression of antioxidant enzymes, heat activation, and defense-related genes. In conclusion, exogenous KT treatment regulates heat tolerance in rice seedlings by modulating the dynamic balance of ROS in plants under heat stress.
