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排序方式: 共有389条查询结果,搜索用时 15 毫秒
31.
Summary Successful widespread use of a forage or biomass plant depends largely on its ease of establishment. Elephantgrass (Pennisetum purpureum Schum.) is used for both forage and biomass production, due to its high dry matter production, aggressiveness, perenniality, and forage quality. However, lack of high quality seed has limited the use of elephantgrass and its hybrids to pearl millet (P. glaucum L. R.Br.). Development of a seed-propagated pearl millet x elephantgrass hexaploid cultivar, which would combine desirable characteristics from both of these species, would be highly desirable. The objectives of this study were to characterize morphological and seed-related traits from the selfed progeny of seven hexaploid hybrids, and to determine whether seed size had any influence on these traits. Traits studied included number of tillers, height, leaf length and width, panicles per plant, days to flowering, panicle length, seed set, seed production, and weight of 100 seeds. Genetic differences were found among the progeny of the seven hybrids. Differences were also found between plants derived from large- and small-seed lots within families. Plants descended from larger seed had better growth and seed-related characteristics, which resulted in more desirable plants. These hexaploid hybrids showed potential for direct seeding into the field for biomass or forage production. 相似文献
32.
G. Velu K. N. Rai V. Muralidharan V. N. Kulkarni T. Longvah T. S. Raveendran 《Plant Breeding》2007,126(2):182-185
Development of crop cultivars with elevated levels of micronutrients is being increasingly recognized as one of the approaches to provide sustainable solutions to various health problems associated with micronutrient malnutrition, especially in developing countries. To assess the prospects of this approach in pearl millet (Pennisetum glaucum), a diverse range of genetic materials, consisting of 40 hybrid parents, 30 each of population progenies and improved populations, and 20 germplasm accessions, was analysed for grain iron (Fe) and zinc (Zn) content, deficiencies of which adversely affect human health. Based on the mean performance in two seasons at ICRISAT, Patancheru, India, large variability among the entries was found, both for Fe (30.1–75.7 mg/kg on dry weight basis) and Zn (24.5–64.8 mg/kg). The highest levels of grain Fe and Zn were observed in well‐adapted commercial varieties and their progenies, and in the parental lines of hybrids, which were either entirely based on iniari germplasm, or had large components of it in their parentage. There were indications of large within‐population genetic variability for both Fe and Zn. The correlation between Fe and Zn content was positive and highly significant (r = 0.84; P < 0.01). These results indicate that there are good prospects of simultaneous selection for both micronutrients, and that selection within populations, especially those with the predominantly iniari germplasm, is likely to provide good opportunities for developing pearl millet varieties and hybrid parents with significantly improved grain Fe and Zn content in pearl millet. 相似文献
33.
In pearl millet (Pennisetum glaucum (L.) R. Br.), single cross hybrids based largely on exotic germplasm, have found very limited adoption in drought-prone arid
regions mainly due to their inadequate adaptation to prevalent extremely harsh agro-climatic conditions. This study tested
the hypothesis that the use of restorer parents derived from adapted landrace germplasm could be an alternative strategy in
developing suitable hybrids for arid regions. Forty inbred restorer lines developed from two phenotypically diverse landraces
were used to develop hybrids evaluated in this study for their performance in five typical arid zone environments between
2003 and 2007. Inbred lines from both landrace populations differed significantly in their combining ability for biomass,
harvest index and grain and stover yields. A larger proportion of experimental hybrids, based on selected inbred lines, significantly
outperformed the commercial checks for grain and stover yields. Increase in grain and stover yields was achieved primarily
due to their higher biomass productivity, with no decline in harvest index. Choice of landrace determined the relative grain
and stover productivity of their hybrids. Phenotypic differences observed in parental landraces in tillering and panicle length
were also visible in their respective hybrids, indicating that characteristics of landrace parental populations were transmitted
in their hybrids. 相似文献
34.
35.
R. K. Kapila R. S. Yadav P. Plaha K. N. Rai O. P. Yadav C. T. Hash C. J. Howarth 《Plant Breeding》2008,127(1):33-37
Genetic diversity among 70 maintainers and two pollinators of sub-Saharan and Indian origin was studied for simple sequence repeat (SSR) loci using 34 primer pairs. A total of 213 alleles were detected with an average of 6.26 alleles per locus. Polymorphic information content (PIC) ranged from 0.05 to 0.96 with a mean of 0.58 for the SSR loci. Mean PIC across the linkage groups and number of alleles in dinucleotide motifs varied significantly. The lowest PIC (0.239) for linkage group 6 indicated comparatively conserved nature of this linkage group. Genetic similarity estimates ranged from 0.05 to 0.73 with an average value of 0.29. This indicated sufficient diversity among the maintainer and pollinator lines. The 72 lines fell in five clusters, and the clustering pattern corroborated with their pedigree and characteristic traits. Pollinator ICMR 356 was more diverse from the maintainer lines analysed, and can be a potential parent for pearl millet hybrid development. 相似文献
36.
37.
J. R. Witcombe 《Euphytica》1988,39(1):11-18
Summary For purposes of comparison of analytical methods the yield data on pearl millet hybrids and varieties for five years from locations in India and Pakistan have been analysed using a regression analysis and a meanstandard deviation analysis. The results of the mean-standard deviation analysis and the regression analysis were similar whether carried out on all environments, or on the highest- and lowest-yielding sets of environments. This was substantiated by the remarkable correlation between the slopes from the regression analysis and the standard deviations whatever environmental set was considered. The validity of using a single year's across location data with the mean-standard deviation analysis, if choice-theoretic criteria are used, was examined. It is concluded that, although further confirmation is required, single-year data seem to suffice. The relative merits of the mean-standard deviation analysis and a regression analysis are discussed; the choice-theoretic framework of the mean-standard deviation analysis is advantageous and complementary to the regression analysis. 相似文献
38.
亚热带牧用草地中威提特东非狼尾草的种子繁殖研究 总被引:4,自引:0,他引:4
在3月和4月对全日制放牧的东非狼尾草草地上的风干牛粪取样,进行发芽试验,分别测定其中的东非狼尾草发芽种子数量。结果,3月取样平均432.5 g的牛粪中东非狼尾草平均发芽种子数量为118.25粒,4月取样平均437.8 g的牛粪中东非狼尾草平均发芽种子数量为52.8粒,二者平均牛粪重为435.15 g,平均发芽种子为85.5粒,说明牛粪中东非狼尾草种子数量较多,是其繁殖扩展较快的主要原因;3月取样的种子数量为4月取样数量的1.38倍,说明人工利用牛粪进行东非狼尾草繁殖时,需在有降雨来临前准备,即1~3月进行牛粪的准备工作。 相似文献
39.
Okagbare GO Akpodiete OJ Esiekpe O Onagbesan OM 《Tropical animal health and production》2004,36(6):593-598
Tropical Animal Health and Production - 相似文献
40.
钼酸钠对低温胁迫下狼尾草渗透调节物质和膜稳定性的影响 总被引:2,自引:0,他引:2
以狼尾草(Pennisetum alopecuroides)为材料,研究了不同质量浓度的钼酸钠对低温胁迫下狼尾草幼苗中几种渗透调节物质含量和细胞膜稳定性的影响。结果表明,钼酸钠可显著提高低温胁迫下的狼尾草叶片总叶绿素、可溶性蛋白质、抗坏血酸、可溶性糖、游离脯氨酸等物质的含量,降低丙二醛含量和细胞膜透性,缓解狼尾草受到的低温冷害;钼酸钠缓解低温胁迫的最低效应质量浓度为0.5 mg·L-1,且在0.5~5.0 mg·L-1质量浓度范围内对狼尾草渗透调节物质和细胞膜稳定性的影响无显著差异。 相似文献