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81.
粗厚山羊草细胞质普通小麦雄性育性光温反应的初步研究 总被引:1,自引:1,他引:0
对粗厚山羊(Ae.crassa)细胞质普通小麦异质系进行2a人工控光试验及分期播种试验.结果表明,粗厚山羊草细胞质普通小麦异质系具有光敏雄性不育特性,温度对育性亦有一定效应;不同异质系的光周期敏感性与核供体品种的光周期敏感性相关;六倍体的粗厚山羊草细胞质异质系与四倍体异质系育性的光周期反应有差异,前者对光周期较为敏感由于异质系育性的光周期反应是核质素作的结果,同时又受到了温度的影响,因此,有可能选育适应不同生态条件的光温敏不育材料. 相似文献
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85.
ZHANG Hong-jun ;Qu Li-jun ;XIANG Chao ;WANG Hui ;XIA Jia-fa ;LI Ze-fu ;GAO Yong-ming ;SHI Ying-yao 《水稻科学》2014,21(4):201-209
Abnormal heading in hybrid rice production has caused great economic loss in recent years,but the genetic basis of this phenomenon remains elusive.In this study,we developed four testcross populations using 38 introgression lines(ILs)from Shuhui 527(SH527)/Fuhui 838(FH838)//SH527population as male parents and four male sterile lines(MSLs;namely II-32A,Xieqingzao A,Gang 46A and Jin 23A)as female parents.Progeny testing allowed us to identify 55 abnormal heading combinations in Hefei,but had late heading date in Hangzhou and Guangzhou of China.By one-and two-way analysis of variance,a total of 21 QTLs and 31 pairs of epistatic QTLs associated with photosensitivity were identified in the four populations,respectively.Genotypic analysis showed that the IL parent of most abnormal heading combinations showed some introgressions at markers RM331 and RM3395 on chromosome 8(strongly associated with the known genes OsHAP3H/DTH8/Ghd8/LHD1)of donor FH838alleles,and these two markers were also identified as affecting photosensitivity.The observation that the recipient parent(SH527),donor parent(FH838),their testcross combinations with four MSLs,and the IL parents of abnormal heading combinations had normal heading date in Hefei suggested that OsHAP3H/DTH8/Ghd8/LHD1 showed no independent regulation on abnormal heading in the abnormal heading combinations.It is noteworthy that complex epistasis among RM331 or RM3395 with other loci,including dominant×additive,additive×dominant,and dominant×dominant epistases,were identified only in the four testcross populations of the current study,but not in the SH527/FH838//SH527 population,suggesting the cause of abnormal heading in abnormal heading combinations in Hefei and delayed heading in Hangzhou and Guangzhou. 相似文献
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该文对单瓣和重瓣紫花木槿雌雄蕊的发育进行了系统的观察.结果表明:单瓣紫花木槿的小孢子母细胞经过减数分裂形成四面体状的四分体,成熟花粉是二细胞型,圆球状,表面有刺,雌蕊发育滞后于雄蕊发育一周左右,即雄蕊发育至单核小孢子时期时,珠心内大孢子母细胞开始进行减数分裂,历经蓼型胚囊的发育模式,发育为成熟胚囊.重瓣紫花木槿的雌雄蕊均瓣化并败育.单瓣紫花木槿开花后第4天开始进行双受精,胚的发育历经球形原胚、心形胚、鱼雷胚、子叶胚及成熟胚时期,核型胚乳,种子成熟后无胚乳. 相似文献
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Near‐isogenic lines (NILs) of apetalous (AP) and fully petalled (FP) winter oilseed rape were used to investigate infection by Sclerotinia sclerotiorum, which occurs mainly via infected petals adhering to leaves in FP oilseed rape. AP1 flowers had an average of 1·4 and 0·8 petals per flower in field and polytunnel experiments, respectively. In field experiments there were no significant differences between counts of FP1 petals, FP1 stamens and AP1 stamens adhered to leaves during flowering. At any one sample time, significantly more stamens tested positive for S. sclerotiorum on AP1 than FP1 NILs, e.g. in 2004, at early flowering 37·5% and 24·2% of stamens tested positive on AP1 and FP1 NILs, respectively. In polytunnel experiments, there were significantly more sclerotinia lesions per plant in the FP1 than in the AP1 NIL. The AP1 NIL did not avoid infection completely, probably because it produced some petals, and lesions were initiated from adhered stamens as well as petals. However, while 8·5% and 16·3% of petals initiated lesions in FP1 and AP1 NILs, respectively, only 2·5% and 1·0% of stamens initiated lesions in FP1 and AP1 NILs, which suggests stamens may be less infective than petals. In field experiments the AP1 NIL had significantly less incidence of sclerotinia stem rot than the FP1 NIL in 2004 (4·9% and 7·0%, respectively). However, there was no significant difference in stem rot incidence between AP and FP lines in 2005 (3·6% and 4·3%, respectively) or 2006 (5·5% and 3·9%, respectively). 相似文献
89.
陈文均 《林业机械与木工设备》2008,(12)
分析了发动机正常运转时的激振源以及它们可能发生的变化.发动机的各种故障会引起个别气缸气体作用力减小,导致总的反倒力矩平衡性恶化,致使发动机横向摆动加大,出现怠速异常振动.通过建立发动机振动测试系统对上述结论进行验证. 相似文献
90.
Summary Our objective was to determine the average numbers of pollen grains from fertile plants (Ms
1) and the average numbers of coenocytic microspores from genetic male sterile plants (ms
1
ms
1) in soybeans, Glycine max L. Merr. Comparisons were made between the average numbers of pollen grains and the average numbers of coenocytic microspores with respect to environment where plants were grown and to stamen position in the flower. Five male sterile lines were used. They included the North Carolina ms
1 mutant, the cultivar Hark with the ms
1 gene, and mutants identified as the Urbana, Tonica, and Ames male steriles. Three environments used were the Agronomy Farm, University of Georgia, Athens, Georgia; the Agronomy and Agricultural Engineering Research Center, Iowa State University, Ames, Iowa; and the Agronomy Greenhouse, Iowa State University, Ames, Iowa.Pollen production from fertile plants varied from 374 to 760 pollen grains per anther among genetic lines and environments. This variation may be an important consideration in selecting a male parent to use as a pollinator for hybrid seed production.Among fertile plants, the average numbers of pollen grains per anther of the separate stamen and and of the lower whorl of stamens were significantly different only in greenhouse-grown plants. Among male sterile plants, the average numbers of coenocytic microspores per anther of the separate stamen and of the lower whorl of stamens were significantly different in three genotype x environment combinations. These three exceptions did not conform to any genetic or environmental pattern. Deviations from the expected ratio of 4 pollen grains from fertile plants: 1 coenocytic microspore from sterile plants were attributed to initial differences in the average number of microspore mother cells between the two genotypes.Joint contribution: Agricultural Research Service, USDA, North Central Region, and Journal Paper No. J-8910 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa 50011; Project 2107. 相似文献