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Grain yields of seven barley cultivars (Hordeum vulgare L.) and 398 doubled-haploid lines derived from their diallel crosses were evaluated in hill plots at two locations in Ontario. Additive × additive epistasis and linkage disequilibrium were detected in the seven cultivars. Additive × additive genetic variance was significantly greater than zero but additive genetic variance was not significantly greater than zero. The narrow-sense heritability on the basis of line means was intermediate (0.33). It was predicted that 13.1% yield improvement could be realized in the next recurrent selection cycle using the doubled-haploid method. 相似文献
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Identification and mapping of a novel Turnip mosaic virus resistance gene TuRBCS01 in Chinese cabbage (Brassica rapa L.) 下载免费PDF全文
Qiaoyun Li Xiaoliang Zhang Qiang Zeng Zhigang Zhang Shuantao Liu Yuhe Pei Shufen Wang Xianxian Liu Wenling Xu Weimin Fu Zhizhong Zhao Xiyun Song 《Plant Breeding》2015,134(2):221-225
We aimed to identify Turnip mosaic virus (TuMV) resistance genes in Chinese cabbage by analysing the TuMV resistance of 43 P1 (resistant), 88 P2 (susceptible), 26 F1, 104 B1 (F1 × P1), 108 B2 (F1 × P2) and 509 F2 individuals. All parents and progeny populations were mechanically inoculated with TuMV‐C4. Both F1 and B1 populations showed TuMV resistance. Resistant: susceptible ratios in the B2 and F2 populations were 1 : 1 and 3 : 1, respectively. TuMV resistance in P1 was controlled by a dominant gene, TuRBCS01. Bulked segregation analysis was performed to identify simple sequence repeat or insertion or deletion markers linked to TuRBCS01. Data from 108 B2 individuals with resistant or susceptible phenotypes were analysed using mapmake r/exp 3.0. Polymorphic marker sequences were blast searched on http://brassicadb.org/brad/ . TuRBCS01 was found to be linked to eight markers: SAAS_mDN192117a_159 (3.3 cM), SAAS_mDN192117b_196 (4.0 cM), SAAS_mDN192403_148 (13.0 cM), SAAS_mGT084561_233 (6.8 cM), BrID10723 (3.3 cM), mBr4041 (3.3 cM), SAAS_mBr4055_194 (2.6 cM) and mBr4068 (4.0 cM). Further, TuRBCS01 was mapped to a 1.98‐Mb region on chromosome A04 between markers BrID10723 and SAAS_mBr4055_194. 相似文献
997.
The development of floral organs in upland cotton (Gossypium hirsutum L.) is related to squares and yield formation. The germination percentage of pollen grains, the rate of anther dehiscence and the length of filaments and styles of 11 upland cotton cultivars were determined before and after high-temperature periods by pollen grain culture in vitro. We aimed to analyze the effects of high temperature on pollen germination in styles and on stamen characteristics. The number of pollen tubes in styles and cytological structure of anthers were also tested under simulation of high temperatures by paraffin sectioning of cotton anthers. We found that the germination percentage of pollen grains and rate of anthers dehiscence of Ke 1053, Simian 4 and the male parent of Xiangzamian 3 were greater than those of other cultivars under high field temperatures. There was no significant difference in the length ratio of filaments and styles and filaments length between 11 upland cotton cultivars under high field temperatures. After high-temperature periods in the field, the difference in pollen germination percentage, anther dehiscence, style and filament length between the 11 cultivars was not significant. The number of pollen tubes in Ke 1053, Simian 4 and the male parent of Xiangzamian 3 was greater than those of other cultivars under the high simulation temperature. The number of deformed pollen grains in anthers was also less than those of other cultivars. These results were consistent with the field conditions. This experiment indicated that germination percentage of pollen grains and the rate of anther dehiscence are useful as indicators for screening high-temperature tolerance. The length ratio of filaments and styles and the filaments length could be used as parameters for screening high-temperature tolerance cultivars. 相似文献
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中国乳制品工业的10年回顾与展望 总被引:2,自引:0,他引:2
宋昆冈 《农产品加工.学刊》2005,(9):31-34,37
回顾了中国乳制品工业的发展历程以及10年来所取得的成就.在分析乳制品市场供需关系变化、人们膳食结构变化、乳品消费现状和消费区域转化的基础上,论述了未来5年中国乳品业的发展前景,指出乳制品行业的企业家和员工要审时度势,与时俱进,齐心协力地推动乳制品行业持续、健康地向前发展. 相似文献
1000.