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排序方式: 共有486条查询结果,搜索用时 15 毫秒
41.
G. Ladizinsky 《Euphytica》1985,34(2):539-543
Summary Seeds of the cultivated lentil are capable of germinating shortly after maturation. The seed dormancy of wild lentil species is due to a hard seed coat. In crosses between the cultivated species L. culinaris and its wild progenitor L. orientalis the hard seed coat of the wild species was controlled by a single recessive gene in homozygous condition. In a cross between the wild species L. ervoides and L. culinaris the hard seed coat of L. ervoides was controlled by a single dominant gene. The significance of the genetics of seed coat hardness in the domestication of lentil is briefly discussed. 相似文献
42.
The F2 progenies of crosses between several cowpea (V. unguiculata) lines were investigated for variation of eye pattern and seed coat colour. It was found that three (W, H, O) and five (R, P, B, M, N) major genes control eye pattern and seed coat colour, respectively. The recessive gene (GO) for restricted eye pattern enables the underlying basic white or cream seed coat colour to be observed. A similar effect is obtained with the recessive gene (rr) for colour expression. The expression of mottling (V), possibly a seed coat pattern, may for be observed when it is combined with the genes for certain eye patterns. The significance of these findings in breeding for consumer preference for specific seed coat colour is discussed. 相似文献
43.
Summary A landrace seed lot of runner bean (Phaseolus coccineus L.), obtained from the Budapest region, Hungary, was separated into five seed groups according to seed coat colour. 131 plants were grown randomly, and observed for 27 morphological and physiological characters. The collected data were analysed by ANOVA.Numerical taxonomy of the data employed Principal Components Analysis to generate scatter diagrams and Cluster Analysis to generate dendrograms, both before and after removing data on the four anthocyanin colour characters (seed coat, calyx, stem and flower colour) as these characters are probably controlled by a single major gene. The progenies from the five distinct parental seed groups showed much overlap in characteristics, indicating that they were not distinct lines but comprised a largely panmictic population.Some character associations were detected: plants from white seeds matured significantly later than those from black seeds, plants from white seeds with a few dark spots produced seeds significantly heavier than average, whereas those from white or black seeds produced significantly lighter seeds, although the average seed yield per plant did not differ significatly. 相似文献
44.
Summary Rhizomania is a disease of sugar beet caused by the furovirus beet necrotic yellow vein virus (BNYVV). Coat protein mediated resistance has been reported for a number of viral diseases. This approach to virus resistance was therefore attempted for control of rhizomania. Two constructs of the coat protein gene of BNYVV were introduced into sugar beet by Agrobacterium-mediated transformation. The mRNA level was estimated to be 0.01% of the poly A+ RNA. Expression of the coat protein gene was under the detection limit of our western blotting protocol i.e. below 0.01 g/50 g (0.02% of the total soluble protein). One transformation event per construct was tested in a greenhouse assay and in rhizomania infested soil in a field trial. In the greenhouse assay, transgenic plants showed a strong reduction of virus multiplication when compared to non-transgenic plants. This result was confirmed in the field trial, where a significant difference in virus multiplication was shown between plants with and without the coat protein gene. 相似文献
45.
根据烟草蚀纹病毒(TEV)CP序列设计合成上下游引物,利用RT-PCR方法获得了TEV CP基因,大小为789 bp。将TEV CP基因克隆到pM D 18-T S im p le V ector,经E coRⅠ/S acⅠ双酶切得到目的片段,并将其定向插入到pET 30a载体中构建了原核表达载体pET 30-TEV CP,重组质粒经E coRⅠ和S acⅠ双酶切鉴定及基因测序验证正确后,转化大肠杆菌BL 21,用IPTG进行诱导表达。结果表明,TEV CP基因在大肠杆菌中获得了高效表达,分子量约为37 ku。以表达产物为抗原免疫家兔,制备了特异性抗血清,其效价为1/1 204。W estern b lot检测结果表明,制备的抗血清可用于检测田间的发病植株。 相似文献
46.
褐藻酸钠涂膜剂的特性研究 总被引:9,自引:1,他引:9
对褐藻酸钠凝胶经冻结和解冻处理后的持水能力、凝胶强度、弹性、韧性及状态变化等特性进行了比较试验。结果表明;褐藻酸钠凝胶的这些性质与凝胶体内的钠和钙的比率直接相关;采用2%的褐藻酸钠溶液与5%的氯化钙溶液凝胶化2min,所形成的凝胶具有很好的涂膜性能。 相似文献
47.
石海英 《沈阳农业大学学报》2005,36(4):448-450
根据已知的大麦黄矮病毒GPV株系的外壳蛋白(Coat Protein CP)和移动蛋白(Movement Protein MP)基因序列合成了CP、MP基因的上下游引物。通过PCR扩增获得含有目的基因的片段,经过SalⅠ和PstⅠ双酶切、连接、转化、重组质粒的酶切鉴定及基因测序,构建了酵母表达载体pGBKT7-GPV-CP和pGBKT7-GPV-MP,用于在酵母双杂交分析中表达诱饵融合蛋白,为进一步筛选小麦cDNA文库内与大麦黄矮病毒互作的寄主因子、克隆寄主因子、推测其种类和功能奠定了基础。 相似文献
48.
本文研究了斯特林发动机热腔壁的热负荷条件,并测试了硅酸铝纤维,蛭石,高铝粉三种绝热层对腔壁温度的影响,实验表明,无论哪一种绝热层,都能明显降低腔壁温度,但效果最好的是硅酸铝纤维绝热层。 相似文献
49.
EIJI TANESAKA EIKO UMEDA MASAYUKI YAMAMOTO KYOJIRO MASUDA KYOJI YAMADA MOTONOBU YOSHIDA 《Weed Biology and Management》2012,12(2):91-97
Sesamum mulayanum is a wild relative of cultivated sesame, Sesamum indicum, and sometimes grows in sesame crop fields as an associated weed. This species shows deep seed dormancy and is characterized by conspicuous purple pigmentation on the lower lip of the corolla. The present study examined the inheritance mode of seed dormancy by using reciprocal progeny from crosses between the two species. The seeds of S. indicum and F1 (S. indicum×S. mulayanum) showed good germination, but those of S. mulayanum and F1 (S. mulayanum×S. indicum) showed deep dormancy. The F2 seeds from both reciprocal crosses showed deep dormancy. These results, combined with the maternal inheritance of seed‐coat characteristics, indicated that the seed dormancy of S. mulayanum can be attributed to its seed‐coat structure (coat‐enhanced dormancy). The F3 (S. indicum×S. mulayanum) seeds varied in their depth of seed dormancy and those seeds with deep dormancy (<50% germination) and those with no or shallow dormancy (≥50% germination) occurred in the expected ratio of 3:1, indicating that this trait is polygenic but is controlled by a single dominant major gene. The purple pigmentation of the corolla was expressed in both reciprocal F1 plants and the presence and absence of pigmentation was segregated among the F2 plants at the expected ratio of 3:1, indicating that this trait is also controlled by a single dominant gene. The segregation of the major gene controlling seed dormancy and that controlling purple pigmentation was not independent (9:3:3:1), indicating that these genes are linked, providing insights on sesame domestication. 相似文献
50.