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Bertrand C. Y. Collard Joseph C. Beredo Bert Lenaerts Rhulyx Mendoza Ronald Santelices Vitaliano Lopena 《Plant Production Science》2017,20(4):337-352
Rice production needs to increase in the future in order to meet increasing demands. The development of new improved and higher yielding varieties more quickly will be needed to meet this demand. However, most rice breeding programmes in the world have not changed in several decades. In this article, we revisit the evidence in favour of using rapid generation advance (RGA) as a routine breeding method. We describe preliminary activities at the International Rice Research Institute (IRRI) to re-establish RGA on a large scale as the main breeding method for irrigated rice breeding. We also describe experiences from the early adoption at the Bangladesh Rice Research Institute. Evaluation of RGA breeding lines at IRRI for yield, flowering time and plant height indicated transgressive segregation for all traits. Some RGA lines were also higher yielding than the check varieties. The cost advantages of using RGA compared to the pedigree method were also empirically determined by performing an economic analysis. This indicated that RGA is several times more cost effective and advantages will be realized after 1 year even if facilities need to be built. Based on our experience, and previous independent research empirically testing the RGA method in rice, we recommend that this method should be implemented for routine rice breeding in order to improve breeding efficiency. 相似文献
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The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and Ⅱ-32A) and several lines in indica rice. The result showed that the abilities to keep the male sterility of the maintainer lines strengthened obviously with the progressive backcrossing. The critical stage to maintain the sterility of CMS lines happened usually in BC5-6 generation. The selection of the recurrent parent gave an obvious influence on the pollen fertility distribution of the later generations. The author has discussed ways of improving of the maintainer lines. 相似文献
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《Plant Production Science》2013,16(3):149-164
AbstractThis review paper examines some of the issues concerned with sustainable production of two major cereal crops – wheat and rice. We compare the perceived threats to sustainability in intensive production of rice in Japan and wheat in Europe, and evaluate the contrasting experiences with minimum tillage as a possible technique for greater sustainability. The contrasts which are presented reveal how perceptions about environmental threats vary widely, and how social and economic factors, as well as purely environmental issues, greatly influence the conclusions reached about sustainability. Before drawing these comparisons, however, we present a brief outline of the two crop systems as practised in Japan and Europe, and describe the experiences in both regions of using minimum tillage.The comparison presented has shown that there are no simple solutions to the problem of sustainability. Management techniques which work well in one situation, for example minimum tillage for wheat, may be inappropriate for another crop. Furthermore, the search for sustainability is strongly constrained by social and economic circumstances which ultimately determine which management options are viable. Indeed, although awareness of the need for more sustainable agricultural practices is growing, both in Japan and Europe, short-term economic considerations continue to be the dominant influence affecting agricultural practice in both regions. 相似文献
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【研究目的】为了选择直观、准确、可靠、经济可行和易于操作的水稻种子纯度鉴定技术;【方法】分析和总结了电泳鉴定法、DNA分子标记鉴定法和叶色标记技术鉴定水稻种子纯度的研究进展及应用概况;【结论】作者认为电泳鉴定法及DNA分子标记鉴定法只能获得杂交水稻杂种纯度的基本数据,不具备有效排除假杂种的功能,也不可能采取后补救措施解决因纯度低而造成的产量损失。白化转绿型叶色标记技术运用在杂交水稻上,将结束传统种子纯度的检测方法,引发种子纯度检测的革命,具有极其广阔的市场前景。 相似文献
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东乡野生稻苗期和穗期的耐寒性研究 总被引:16,自引:4,他引:16
东乡野生稻苗期和抽穗开花期的耐寒性表现:比粳稻耐寒性强,尤其苗期耐寒性特强,耐寒性高1个等级。抽穗开花期在连续3d自然低温(16.9℃、14.9℃、16℃的日平均温度),结实率达70%以上。抽穗结实时间直至10月31日,平均结实率2.5%。比籼粳稻耐寒品种结实期长6d左右,但抽穗能结实正常时期与籼粳稻耐寒品种相似。 相似文献
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大米糖浆替代乳糖对早期断奶仔猪生长性能及胰岛素样生长因子轴的影响 总被引:1,自引:1,他引:1
本文旨在研究大米糖浆取代乳糖后对早期断奶仔猪生产性能及胰岛素样生长因子轴的影响.选用7 d断奶的二元杂交仔猪(长白×大白)32头,随机分为2个处理组,每组设16个重复,每个重复1只.日粮成分除乳糖水平外(乳糖组和大米糖浆组分别为43.5%和0),其他成分均一致.试验期14 d,在试验第7天、第14天和第21天对试验猪进行空腹8 h称重,计算试验期日增重及日耗料,并分别于试验第7天和第14天每组随机抽取5头,颈静脉采血,屠宰速取肝脏和背最长肌组织.结果表明,大米糖浆取代乳糖后对仔猪的日增重及肉料比均没有显著影响(P>0.05),14 d大米糖浆组血清GH水平与乳糖组差异不显著(P>0.05),21 d大米糖浆组血清GH水平极显著低于乳糖组(P<0.01);但大米糖浆组14 d和21 d血清IGF-Ⅰ的水平,及肝脏和背最长肌IGF-Ⅰ mRNA相对表达量与乳糖组差异均不显著(P>0.05).综合分析认为,大米糖浆替代乳糖后对早期断奶仔猪的生长性能和胰岛素样生长因子轴没有影响. 相似文献