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991.
992.
Zhi-Juan Ji Xiao-Guang Wang Yu-Xiang Zeng Liang-Yong Ma Xi-Ming Li Bing-Xin Liu Chang-Deng Yang 《Breeding Science》2012,62(1):71-77
Five physiological and eleven yield traits of two pairs of sister lines generated from a high generation with similar genetic background (SLs) for purple pericarp were investigated to explore the reasons behind low-yield production of colored rice. Of the five physiological traits examined, except grain anthocyanin content, there were generally similar trends between the P (purple-pericarp) lines and the corresponding W (white-pericarp) lines over two seasons (in the year 2009 and 2010 separately). The results demonstrated that the chlorophyll content of flag leaves, the net photosynthetic rate of flag leaves, and the grain anthocyanin content could be easily influenced by the environment. The physiological functions of the traits for the P lines were more active than those of the corresponding W lines in the year 2010. The grain anthocyanin content of the P lines was much greater in the year 2010 than in the year 2009 during the growth period. The investigation of yield traits revealed that the P lines had reduced 1000-grain weight, yield per plot and grain/brown rice thickness compared to the W lines. A difference comparison of these traits and a source-sink and transportation relationship analysis for these SLs suggested that small sink size was a key reason behind yield reduction of purple pericarp rice. 相似文献
993.
994.
以小麦面粉为原料,研究了淀粉共生蛋白对淀粉酶解性质的影响。对洗淀粉过程中影响蛋白含量的条件进行了单因素试验,用SDS溶液和蛋白酶进一步除去淀粉中的蛋白质成分,然后对制得的含氮量不同的淀粉样品进行酶解。试验结果表明,蛋白酶能有效地去除淀粉共生蛋白,而淀粉共生蛋白有助于淀粉的水解。 相似文献
995.
Li Xiaofei Han Yingchun Wang Guoping Wang Zhanbiao Feng Lu Yang Beifang Fan Zhengyi Lei Yaping Xiong Shiwu Xing Fangfang Li Yabing 《棉花学报》2013,32(5):472-482
Cotton-based intercropping systems are one of modern agriculture farming systems aiming at improving overall economic profitability of cotton field, which not only release the competition for land between other crops and cotton and increase growing area and yield of both crops, but also represent a mechanistic approach to reconciling crop production and biodiversity conservation. Recently, cotton-based intercropping systems have been widely focused and applied. Here, we reviewed the potential of cotton-based intercropping systems to reinforce agroecosystem services and functioning, including promoted plant biodiversity, improved overall productivity and economic profits, increased light use efficiency, improved cotton quality, reduced pest and disease occurrence, and suppressed weed growth. Further, the underlying mechanisms behind the enhancement of agroecosystem services and functioning by cotton-based intercropping systems through niche complementarity, interspecific facilitation, and allelopathy between intercropped species were summarized in the paper. Finally, the research prospects were also pointed out. 相似文献
996.
亚洲棉同源四倍体种质创新初探 总被引:1,自引:1,他引:0
采用秋水仙碱琼脂糖凝胶涂抹法,处理亚洲棉(Gossy pium arboreum)幼苗茎尖生长点,研究亚洲棉同源四倍体种质创新的诱变浓度与诱变时间,得出最佳诱变参数:浓度0.1%,时间1d.与对照株相比,获得的诱变株矮壮,节间缩短;子叶变大、肥厚,且脱落时间延迟;真叶出现晚,叶裂数不一,叶形不对称,叶面凹凸不平,出现卷曲叶、勺状叶,铲形叶等变异;着生子叶的茎杆处和子叶柄处出现瘤状;叶色浓绿.实验还发现19:00~20:00在温室进行处理,有助于提高诱变率. 相似文献
997.
大豆新品种中黄30种植密度试验 总被引:1,自引:0,他引:1
为了探索大豆新品种中黄30在承德地区的最佳种植密度,试验采用回归设计法,设种植密度18.0万、22.5万、27.0万、33.8万、36.0万和45.0万株/hm 2计6个处理,对不同种植密度下的大豆病虫害发生情况和产量进行了分析;并对其种植密度与产量的关系进行了回归分析,建立了回归方程。结果表明:在试验设定的密度范围内,随着种植密度的增大,大豆虫食率、褐斑病率和紫斑病率均呈先降低后升高的变化趋势,其中密度为22.5万株/hm 2时,3种病虫害的发生率均最低,分别为0.4%、0.5%和0.1%;大豆产量呈先增加后降低的变化趋势,产量与种植密度的二次回归方程为 Y =-2731.4259+358.9022 X-5.0335X 2。本研究条件下,密度为33.8万株/hm 2时大豆产量最高,为3801.667 kg/hm 2。 相似文献
998.
残料加工对编程来说是一个比较复杂的环节,不同的软件拥有不同的功能,对不同形状的零件有不同的加工方法,文章针对UG CAM模块,了解其残料加工的原理,优化这些加工方法,追求更安全、更高效的残料粗加工方法。 相似文献
999.
1000.
This study empirically investigates the direct and indirect (spillover) effects of three types of industrial agglomeration with different cognitive distances, namely, industrial specialization, industrial related variety, and industrial unrelated variety, on regional innovation. Accordingly, we applied the concepts of related and unrelated variety and used spatial econometric analysis. Based on panel data of 283 Chinese cities from 2004 to 2016, the empirical results reveal that both industrial specialization and industrial related variety significantly improve regional innovation and produce positive spatial spillover effects on the surrounding regions. However, industrial unrelated variety has a significant negative impact on regional innovation and produces a negative spatial spillover effect on the surrounding regions. Moreover, the direct and indirect effects of the three types of industrial agglomeration on regional innovation between China's coastal and inland cities. The findings have important theoretical and policy implications. 相似文献