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排序方式： 共有833条查询结果，搜索用时 20 毫秒
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De-wei Yang Xiang-hua Zheng Chao-ping Cheng Wen-da Wang Deng-hui Xing Li-bin Lu Chen-de Liu Ning Ye Mei-juan Zeng Xin-fu Ye 《Euphytica》2014,197(1):145-159
Dwarf mutants in plants are crucial for elucidating regulatory mechanisms for plant growth and development. Previous studies suggested that the heterotrimeric G-protein alpha subunit known as D1/RGA1 in rice was involved in deactivation function of the G protein. However, so far no partner has been analyzed the spatial structure change acting with D1. In this study, a dwarf mutant designated Mu101 was obtained in M2 population of rice indica cultivar M804 treated with 60Co γ-ray. Genetic analysis of Mu101 indicated that the dwarf phenotype was controlled by a single dwarf gene, and the dwarf mutant was insensitive to gibberellin (GA), which was named dwarf 89 (d89). Using a large F2 population derived from a cross between the d89 and a japonica rice variety, Taigeng16, the D89 gene was fine mapped into a 62.13 kb physical distance on chromosome 5, where eight open reading frames were predicted. Sequence analysis indicated that only one bp substitution (A-G) was found in LOC_Os05g26890 between M804 and the d89 mutant. The rice GA insensitive dwarf mutant DWARF1 gene was in this locus. The modeling analysis showed amino acid threonine to alanine mutation was likely to make the alpha helix short, and led to the G protein deactivation. 相似文献
3.
Ping Liu Zhiwu Dan Zhe Wang Shaoqing Li Nengwu Li Huanxin Yan Xingxing Cai Bao-Rong Lu 《Euphytica》2015,203(1):47-57
4.
水稻叶片形态建成分子调控机制研究进展 总被引：10，自引：2，他引：8
叶片形态是水稻“理想株型”的重要组成部分,是当前水稻高产育种关注的重点。本文通过对已克隆多个叶形相关调控基因综述了水稻叶片形态(叶片卷曲度、倾角、披散程度以及叶片宽度)建成的分子遗传学研究进展。综合分析认为,水稻叶片的卷曲主要是通过卷叶基因调控叶片近轴/远轴间的发育、泡状细胞的发育及其膨胀和渗透压、厚壁组织的形成以及叶片角质层的发育等来实现。影响植株空间伸展姿态的叶倾角主要通过叶角基因调控油菜素内酯的信号传导来影响叶枕细胞的生长发育;唯一被克隆的影响叶片披垂度的披叶基因DL1是通过控制叶片中脉发育而改变叶片形态的;而窄叶基因则主要通过调控生长素的合成与极性运输、维管组织的发育和分布,影响叶片维管束数目及宽度。但到目前为止,所有已克隆的叶形调控基因间相互调控关系的研究还不够深入,还不能完整清晰地勾勒水稻叶形建成和发育的分子调控网络。因此,在已有的研究基础上更深入地探索水稻叶片形态建成的分子调控机制,对进一步构建相关的调控网络,塑造水稻理想株型具有重要意义。 相似文献
5.
《European Journal of Agronomy》2011,34(4):276-284
A measure of a crop's nitrogen (N) status can be obtained by relating the actual N concentration of the crop to the critical plant nitrogen concentration (PNCc), the minimum N concentration required for maximum growth. In annual crops, PNCc declines as plant size increases. Describing this decline is one of the main challenges for the implementation of the PNCc concept in fertilizer management strategies. From two field experiments with repeated harvests of Dutch white cabbage and with N supply ranging from limitation to excess, the relation between PNCc and weight per unit ground area of plant dry matter exclusive of roots (W) was estimated as: PNCc = 5.1W−0.33% for the linear growth phase (W > 1.5 t ha−1; LAI > 1.4). From a third field experiment, a value of 4.5% N was estimated for PNCc for the pre-linear growth phase. Also a power function: LAR = 0.011W−0.33 described the relationship between leaf area ratio and weight. The exponent of the power function determines the rate of the decline. Therefore, having the same value of the exponent: −0.33, LAR and PNCc declined at the same rates. The proportional decline in LAR and PNCc corresponded to a constant nitrogen content on a leaf area basis of 4.7 g N m−2 until onset of head formation. 相似文献
6.
HUANG Qi-na # YANG Yang SHI Yong-feng CHEN Jie WU Jian-li State Key Laboratory of Rice Biology/Chinese National Center for Rice Improvement China National Rice Research Institute Hangzhou China College of Life Environmental Sciences Hangzhou Normal University Hangzhou 《水稻科学》2010,17(4):247-256
Many rice spotted-leaf(spl) mutants are ideal sources for understanding the mechanisms involved in blast resistance,bacterial blight resistance and programmed cell death in plants.The genetic controls of 50 spotted-leaf mutants in rice have been characterized and a few spotted-leaf genes have been isolated as well.This article reviews the origin,genetic modes,isolation and characterization of spotted-leaf genes responsible for their phenotypes,and their resistance responses to main rice diseases. 相似文献
7.
《Journal of Cereal Science》2013,57(3):706-712
Allele mining in starch synthesis-related genes (SSRGs) has facilitated the discovery of desired natural sequence variations for eating quality in rice. This study investigated the sequence variations from 10 SSRGs, and further evaluated their relationship with the amylose content (AC) and rapid viscosity analysis profiles in a global collection of rice accessions by association mapping (AM). In total, 83 sequence variations were found in 10 sequenced amplicons, including 73 single nucleotide polymorphisms (SNPs), eight insertion-deletions (InDels) and two polymorphic simple sequence repeats (SSRs). Four subpopulations were identified by population structure analysis based on 170 genome-wide SSR genotypes. AM revealed 11 significant associations between three phenotypic indices and three sequence variations. One SNP with a g/c transversion at the 63rd nucleotide downstream of the OsBEIIb gene termination codon on rice chromosome 2 was significantly associated with multiple trait indices in both the general linear and mixed linear models (GLM and MLM), including the final viscosity (p < 0.001, R2 = 23.87%) in both 2009 and 2010, and AC (p < 0.01, R2 = 11.25%) and trough viscosity (p < 0.01, R2 = 20.43) in 2010. This study provides a new perspective of allele mining for breeding strategies based on marker-assisted selection. 相似文献
8.
Tillage changes the physical and chemical properties of soil and can also inhibit or enhance useful and harmful fauna. In agriculture, different tillage technologies are being tried to enhance crop productivity, but little concrete information seems to exist on their effects on pest abundance and damage. To address this lack of information, sowing of wheat was investigated under different tillage systems. In order to monitor pest abundance and damage in altered tillage systems, the present studies on the relative abundance and damage due to insect pests viz. pink stem borer (PSB, Sesamia inferens Walker), termites (Microtermes obesi Holmgren and Odontotermes obesus Rambur) and root aphid (Rhopalosiphum rufiabdominalis Sasaki) were undertaken in a rice–wheat cropping system during 2010–11 and 2011–12. Pest abundance and damage was monitored in four tillage systems i.e. conventional tillage (CT), zero tillage (ZT), ZT + mulch and rotary tillage (RT) under insecticide protected and unprotected conditions. The application of insecticide did not affect root aphid incidence or termite damage. However, significant differences in PSB damage in insecticide protected (0.9%) and unprotected (1.2%) conditions were observed. The investigations demonstrated that in CT, damage by PSB (0.6%) was minimum; however termite damage (2.2%) was maximum as compared to all other tillage conditions. In ZT, PSB damage (1.4%) was maximum and root aphid incidence (3.1 aphids/tiller) was minimum in comparison to other tillage conditions. ZT + mulch resulted in inter-mediate insect pest incidence/damage; however, RT was the least effective practice which showed relatively high incidence/damage of these three insects (1.2% PSB damage, 1.9% termite damage and 5.1 aphids/tiller). The insecticide × tillage interaction indicated that insecticide application is needed only in ZT and RT for PSB management. 相似文献
9.
Echinochloa colona (L.) Link. is one of the most problematic weeds across the world. It is an annual C4 summer grass, native to tropical and subtropical Asia, emerged as a serious and persistent threat in 35 cropping systems in more than 60 countries. E. colona is reported as an important associated weed species in transplanted and direct-seeded rice. Diverse ecotypes, high seed production, short seed dormancy, rapid growth, competitive potential, allelopathic interaction, and resistance against several herbicides makes it a more adaptable and persistent challenge in various agro-ecosystems. Development of resistance to recommended or higher doses of numerous herbicides, including ametryn, atrazine, bispyribac-sodium, clefoxidym, cyhalofop-butyl, fenoxaprop-p-ethyl, glyphosate, metribuzin, propanil, and triazine, is a serious concern for the farming and scientific community. Crop infestation with resistant E. colona biotypes may ultimately increase the weed control cost. Unfortunately, investigations on seed dormancy release, genetic diversity, allelopathic interference, and competitive ability of this weed are inadequate in accomplishing its appropriate control in different environments. Therefore, a comprehensive review is presented here to gather the existing information, to pin point key findings, and to highlight the research gaps in the biology, interference, and management of E. colona. Different management options have been discussed in relation with eco-biology of this noxious weed. The potential research endeavours have also been highlighted in order to provide an insight of its existing scenario and to facilitate the future management strategies. 相似文献
10.
《Field Crops Research》2006,95(2-3):156-170
Sugarcane (Saccharum spp.) is grown across different production environments and is harvested over a 5-month (mid-October–mid-March) period in Florida. While many studies have examined genotype × environment interactions and their implications for breeding program design, knowledge is limited regarding interactions of genotype, environment and time of harvest and their implications for growers. Three non-confounded data sets (“case studies”) were analyzed to determine the effects of these three factors on kilograms of sugar per ton (KST), tons of cane per hectare (TCH) and tons of sugar per hectare (TSH) for recently released cultivars in south Florida. Cultivar (genotype), environment, time of harvest and their interactions had significant effects on KST, TCH and TSH. Sugarcane KST and TSH were reduced by 28 and 29%, respectively, when harvested in mid-October compared to optimum harvest dates in February. TSH varied from 2 to 46% across environments. The Lakeview “warmland” site near Lake Okeechobee recorded significantly higher TCH and TSH than other sites, and cultivars CP88-1508 and CP88-1834 recorded higher relative yields at Lakeview. Cultivar TSH varied up to 51% across the case studies. CP89-2143 had significantly higher KST than other cultivars in all 21 pairwise comparisons in the three case studies, and a remarkably high, stable KST ranking across environments. Growers in the Everglades Agricultural Area interested in improving sugarcane crop sucrose concentration should plant CP89-2143. However, significant genotype × environment interactions for other cultivars support continued multi-locational evaluation of sugarcane germplasm both during the breeding program and following cultivar release. 相似文献