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本文从颖花发育的形态学和生理学角度,综述了水稻穗分化期至抽穗开花期非生物胁迫导致颖花不育的机理,旨在揭示非生物胁迫导致水稻颖花败育的关键过程及其内在联系.颖花是否可育主要与绒毡层细胞行为、花药开裂与散粉、花粉萌发、受精4个关键过程有关,胁迫通过影响这些关键过程,导致颖花不育.花药发育早期异常变化影响生殖细胞发育与授粉作用.可以通过喷施外源物质或增施硅肥等方法减缓非生物胁迫对颖花育性的伤害.今后需要加强交叉胁迫对颖花育性的影响、不同胁迫对花器官形态结构和生理特性的影响、不同水稻品种对胁迫的响应差异,以及胁迫影响花器官发育的分子生物学机制等方面的研究. 相似文献
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Xiangjun Kong Aziz Khan Zhiling Li Jingyi You Fazal Munsif Haodong Kang Ruiyang Zhou 《Saudi Journal of Biological Sciences》2020,27(12):3691-3699
Chalcone synthase (CHS) is a key enzyme and producing flavonoid derivatives as well play a vital roles in sustaining plant growth and development. However, the systematic and comprehensive analysis of CHS genes in island cotton (G. barbadense) has not been reported yet especially response to cytoplasmic male sterility (CMS). To fill this knowledge gap, a genome-wide investigation of CHS genes were studied in island cotton. A total of 20 GbCHS genes were identified and grouped into five GbCHSs. The gene structure analysis revealed that most of GbCHS genes consisted of two exons and one intron, and 20 motifs were identified. Twenty five pairs duplicated events (12 GbCHS genes) were identified including 23 segmental duplication pairs and two tandem duplication events, representing that GbCHS gene family amplification mainly owned to segmental duplication events and evolving slowly. Gene expression analysis exhibited that the GbCHS family genes presented a diversity expression patterns in various organs of cotton. Coupled with functional predictions and gene expression, the abnormal expression of GbCHS06, 10, 16 and 19 might be associated with pollen abortion of CMS line in island cotton. Conclusively, GbCHS genes exhibited diversity and conservation in many aspects, which will help to better understand functional studies and a reference for CHS research in island cotton and other plants. 相似文献
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R. J. Kemble 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(3):364-370
Summary An assay is described whereby Eco RI restriction fragment length polymorphisms of mitochondrial and chloroplast DNAs can definitively identify cytoplasms of interest in Brassica crop development. Restrictable mitochondrial and chloroplast DNA is extracted from as little as 2–3 g and 0.5 g leaf tissue, respectively, and the donor plants are able to continue to develop in a normal manner. An unknown cytoplasm can be identified in three days, which is a considerable saving in time and labor compared to the several years required by traditional methods. The assay is very inexpensive and should be established as a routine procedure in laboratories involved in sexual or somatic Brassica hybrid production. 相似文献
6.
Ri-Sheng Tang Jian-Chu Zheng Zhi-Qing Jin Da-Dong Zhang Yi-Hong Huang Liu-Gen Chen 《Plant Growth Regulation》2008,54(1):37-43
In order to explore the possible physiological mechanism of high temperature induced sterility in rice, we examined the floret
sterility and endogenous plant growth regulator contents in pollens of two hybrid rice cultivars Shanyou63 and Teyou559 that
are tolerant and susceptible to high temperature, respectively. Indexes of floret sterility, pollen activity, and variation
of endogenous indole-3-acetic acid (IAA), gibberellic acids (GAs), abscisic acid (ABA), free proline and soluble proteins
in anthers were measured. We found that during the course of high temperature treatment, both cultivars exhibited a marked
decrease in pollen activity, pollen germination and floret fertility; however, the high temperature tolerant Shanyou63 showed
a much slower rate of decrease than the high temperature susceptible Teyou559. In addition, anthers of both cultivars displayed
a decrease in the contents of IAA, GAs, free proline and soluble proteins but an increase in the ABA content. Yet compared
to Teyou559, Shanyou63 retained significantly higher levels of free praline and GAs and a lower level of ABA, along with higher
pollen vigour and pollen germination rate even after prolonged high temperature treatment. Our study suggests a possible correlation
between pollen viability/floret sterility and high temperature-caused changes in IAA, GAs, ABA, free proline and soluble protein
contents. The severity in these changes may reflect the variation of rice cultivars in their heat stress sensitivities for
floret development. 相似文献
7.
M. Z. Liang L. J. Ou L. X. Deng S. Luan L. B. Chen 《Russian Journal of Plant Physiology》2008,55(5):694-698
The aim of this work was to develop a photoperiod-sensitive male sterile rice with stable sterility. We developed Changguang S, an indica rice strain, by using a short critical day length. Differences in the fertility responses of Changguang S strain pollen to temperature and photoperiod under natural and controlled conditions were studied. The results showed that Changguang S strain exhibited stable sterility under long-day and low-temperature conditions (22°C, 15 days). The stability of sterility was significantly higher than that of other such rice strains, Nongken 58S and 7001S. The critical photoperiod for inducing male sterility in Changguang S was 13 h or shorter, and its duration was significantly shorter than that required for rice strains Nongken 58S and 7001S. It is suggested that Changguang S is a typical photoperiod-sensitive male sterile rice strain with a shorter critical day length and a lower critical temperature. It is promising to apply this strain to two-line hybrid rice production. 相似文献
8.
Surfing parameter hyperspaces under climate change scenarios to design future rice ideotypes 下载免费PDF全文
Livia Paleari Ermes Movedi Lloyd T. Wilson Roberto Confalonieri 《Global Change Biology》2017,23(11):4651-4662
Growing food crops to meet global demand and the search for more sustainable cropping systems are increasing the need for new cultivars in key production areas. This study presents the identification of rice traits putatively producing the largest yield benefits in five areas that markedly differ in terms of environmental conditions in the Philippines, India, China, Japan and Italy. The ecophysiological model WARM and sensitivity analysis techniques were used to evaluate phenotypic traits involved with light interception, photosynthetic efficiency, tolerance to abiotic stressors, resistance to fungal pathogens and grain quality. The analysis involved only model parameters that have a close relationship with phenotypic traits breeders are working on, to increase the in vivo feasibility of selected ideotypes. Current climate and future projections were considered, in the light of the resources required by breeding programs and of the role of weather variables in the identification of promising traits. Results suggest that breeding for traits involved with disease resistance, and tolerance to cold‐ and heat‐induced spikelet sterility could provide benefits similar to those obtained from the improvement of traits involved with canopy structure and photosynthetic efficiency. In contrast, potential benefits deriving from improved grain quality traits are restricted by weather variability and markedly affected by G × E interactions. For this reason, district‐specific ideotypes were identified using a new index accounting for both their productivity and feasibility. 相似文献
9.
Wenyi Yan a bc Shenghai Ye b Qingsheng Jin b Longjun Zeng c Yu Peng c Dawei Yan c Weibing Yang c Donglei Yang c Zuhua He c Yanjun Dong a Xiaoming Zhang b a College of Life Environment Sciences Shanghai Normal University Shanghai China b Institute of Crop Nuclear Technology Utilization Zhejiang Academy of Agricultural Sciences Hangzhou China c Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China 《Acta Genetica Sinica》2010,(1)
Plant senescence plays diverse important roles in development and environmental responses.However,the molecular basis of plant senescence is remained largely unknown.A rice spontaneous mutant with the character of early senescence and male sterility (sms) was found in the breeding line NT10-748.In order to identify the gene SMS1 and the underlying mechanism,we preliminarily analyzed physiological and biochemical phenotypes of the mutant.The mutant contained lower chlorophyll content compared with the wild t... 相似文献
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