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251.
Variation in Anther Culture Response and Fertility of Backcrossed Hybrids between Indica and Japonica Rice (Oryza sativa) 总被引:2,自引:1,他引:1
This study was conducted to investigate the variations of fertility, callus induction and plant regeneration in backcrossed hybrids between a responsive japonica variety (Mankeumbyeo, recurrent parent) and a recalcitrant indica variety (Ranta Emas, donor parent) to anther culture. The mean spikelet fertility of inter-subspecific F1 and BC1F1 hybrids was 33.5% and 67.2%, and the spikelet fertility of BC1F1 among backcrossed hybrids showed the most extensive variation (a low of 4.5% to a high of 90.6%). The mean fertility and distribution range in BC5F1 hybrids were almost the same as that of the japonica recurrent parent (94.6%). The mean callus induction of F1 and BC1F1 hybrids was higher than that of donor parent, and the distribution range in BC1F1 hybrids varied from a low 0% to a high 18.7%. The mean callus induction and plant regeneration of BC4F1 hybrids was almost that of japonica recurrent parent, and there were no statistical differences between BC4F1 and BC5F1 hybrids. These results may help to accelerate the introgression of desirable traits from indica into japonica rice using anther culture of backcross hybrids as a breeding strategy. 相似文献
252.
Joseph S. Di m May cor Diouf Cristina Armas Graciela M. Rusch Francisco I. Pugnaire 《Journal of Plant Ecology》2018,11(3):375
Aims Addressing plant responses to water stress is critical to understand the structure of plant communities in water-limited environments and to forecast their resilience to future changes in climate. In a semiarid agroforestry system in the Sahelian savannah of Leona (Senegal), we selected nine common tree species and explored their stress-resistance mechanisms. These species represent a variety of life forms and are of high regional socio-economic importance. We hypothesized that different species would show different suites of traits to cope with water stress and expected to identify functional groups differing in strategies to withstand water shortage.Methods Along a dry and a wet season, we monitored four traits reflecting above- and below-ground strategies of resource acquisition such as predawn leaf water potential (ψ pd), specific leaf area (SLA), leaf thickness and leaf area index (LAI). We also measured two morphological traits: trunk diameter and tree height. LAI and ψ pd were measured six times during the dry and rainy seasons, and the other traits were measured once.Important findings We identified two functional classes subdivided into two functional groups of each class. The first class included deciduous and semi-deciduous species that generally had large SLA, low leaf thickness and small-to-intermediate inter-seasonal variations in ψ pd. The second class included evergreen species of two functional groups that differ in SLA, leaf thickness and the magnitude of inter-seasonal variations of ψ pd throughout the year. The four functional groups identified in this study represent plant strategies differing in their response to changing environmental conditions. 相似文献
253.
2005年多国合作的国际水稻(Oryza sativa)基因组测序项目绘制了粳稻(O.sativa subsp.japonica)品种日本晴的参考基因组序列。最近,中国科学家发布了2个籼稻(O.sativa subsp.indica)品种(明恢63和珍汕97)的高质量参考基因组序列,为籼稻的功能基因组学研究和分子育种应用提供了便利。 相似文献
254.
印楝提取物的杀虫活性及其中四降三萜研究 总被引:6,自引:1,他引:5
从印楝(Azadirachta indica)种仁的提取物中分离得到10仆四降三萜化合物,能过波谱方法鉴定,它们分别是nimbin(1),deacetylnimbin(2),salannolide(3),azadirachtin(4),vepaol(5),isovepaol(6),3-tigloyl-azadirachtol(7),1-tigloyl-3-acetyl-azadirachtinin(8),3-tigloy-azadirachtinin(9),1-tigloy1-3-acetyl-11-hydrox-ymeliacarpinin(10)。此外,还得到β-谷甾醇、豆甾醇、胡萝卜甙和硬脂酸。含印楝素(azadirachtion)为0.5%的印楝提取物在稀释150-800倍时对小菜蛾和菜粉蝶的人较强的防治作用。 相似文献
255.
Helena Mathews R. E. Litz H. D. Wilde S. A. Merkle H. Y. Wetzstein 《In vitro cellular & developmental biology. Plant》1992,28(4):172-178
Summary Somatic proembryos of mango (Mangifera indica L. cv. Hindi) were co-cultivated withAgrobacterium tumefaciens strain A208 harboring pTiT37-Se::pMON 9749 (9749 ASE). Transformed somatic proembryos capable of growing on selection medium
containing 200 μg/ml kanamycin produced the characteristic indigo blue precipitate in the presence of 5-bromo-4-chloro-3-glucuronic
acid. These proembryos were chimeral consisting of transformed (blue) and nontransformed (yellow/white) cells. A stepwise
selection strategy was found necessary to eliminate chimeras. a) Initial screening at 200 μg/ml kanamycin to enable growth
of transformed cells, b) further screening at 400 μg/ml kanamycin to reduce chimeras, and c) recovery of pure transformed
clones of proembryos in liquid selection medium with 100 μg/ml kanamycin. The integration of the NPT II and GUS genes into
mango genome was confirmed by Southern hybridization. 相似文献
256.
影响籼稻花药培养诱导率的因素及基因型的作用研究 总被引:13,自引:2,他引:13
本文研究了影响籼稻花药培养诱导率的9种重要因素的作用。供试品种和杂种共70余种。结果发现,不同基因型的培养力存在很大差异,这种差异表现在对各种因素上,如基本培养基成分、激素的种类与配比、对低温预处理的时间等等不同反应上。低温预处理是提高籼稻出愈率的有效措施,但由于不同基因型小孢子对低温的耐受力不同,所需的适合预处理时间也就不同。花药接种后先在30℃下培养3天后,再转入26℃下培养,较直接培养在26℃下可大幅度提高花粉檀株的产量。诱导培养基中补加脯氨酸、马铃薯提取液对提高出愈率和绿苗分化率有明显效果。 相似文献
257.
XIE Kabin ZHANG Jianwei XIANG Yong FENG Qi HAN Bin CHU Zhaohui WANG Shiping ZHANG Qifa & XIONG Lizhong . National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene Research 《中国科学:生命科学英文版》2005,48(5):445-451
Rice has become a model plant for genomic studies of monocot species, because of its relative small ge-nome size (430 Mb), high synteny with other impor-tant crop species such as maize, barley and wheat, the release of draft sequences of both indica[1] and japon-ica[2] genomes, and the near completion of the map-based sequencing of rice genome by the Interna-tional Rice Genome Sequencing Project. Currently, more than 340 Mb of non-overlapping genomic se-quences including completely sequenced… 相似文献
258.
259.
Mo-Zhu Wang Hong-Li Li Chun-Xiang Liu Bi-Cheng Dong Fei-Hai Yu 《Journal of Plant Ecology》2022,15(4):795
克隆植物蛇莓对光照强度和养分条件的适应性可塑性
表型可塑性可帮助植物缓冲环境压力并使其表型与当地环境相匹配,但目前仅少数性状的可塑性被广泛认为是适应性的。为充分理解可塑性的适应性意义,仍需进一步研究更多的植物功能性状及其环境因子。本研究将匍匐茎克隆植物蛇莓(Duchesnea indica)的21个基因型种植于不同的光照和养分条件下,并利用选择梯度分析检测了形态和生理可塑性对光照强度和养分有效性变化的适应性值。在遮荫条件下,蛇莓适合度(果实数、分株数和生物量)降低,节间缩短变细,成熟叶叶绿素含量降低,但叶柄长度、比叶面积、老叶叶绿素含量均增加。在低养分条件下,植株叶柄缩短,叶面积缩小变厚,叶绿素含量降低,但果实数量和根冠比增加。选择梯度分析表明,叶柄长度和老叶叶绿素含量对光照变化的可塑性是适应性的,老叶和成熟叶叶绿素含量对养分变化的可塑性也是适应性的。因此,不同性状的可塑性适应值取决于特定的生态背景。该研究的发现有助于理解克隆植物表型可塑性响应环境变化的适应性意义。 相似文献