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951.
甘薯在控制人类许多疾病(如癌症、糖尿病和心脑血管疾病等)方面具有药用价值。同时,甘薯还具有抗氧化、预防肥胖和增强免疫力等保健功能。系统综述近年来甘薯的保健功能及药用价值方面的研究成果,并对其应用进行展望。 相似文献
952.
近年来,小麦叶锈病发生有加重趋势,培育抗病品种是减轻小麦叶锈病危害的环保有效途径。用12个小麦品种及35个含已知抗叶锈病基因的载体品系在苗期接种19个不同毒性的叶锈菌生理小种,通过基因推导和系谱分析发掘待测品种中的抗叶锈病基因,并通过分子标记检测进一步验证;在田间接种强毒性混合生理小种,进行成株期病情严重度与普遍率调查,筛选慢锈性品种。结果表明,在石新828、百农3217、济南2号、泰山1号、石特14、晋麦2148、烟农15、小偃6号、温麦6号共9个品种中检测到Lr1、Lr26、Lr34、Lr37和Lr46共5个抗叶锈病基因,其中部分品种中发现多个抗性基因。成株期筛选出百农3217、平阳27、济南2号、泰山1号、石特14、晋麦2148、碧蚂4号、烟农15、小偃6号、温麦6号共10个慢叶锈性品种,其中碧蚂4号和小偃6号等品种是我国小麦育种的骨干亲本,探究这些品种中的抗病基因对培育小麦抗叶锈病品种具有重要意义。 相似文献
953.
Xing ZHOU Yan-hong LU Yu-lin LIAO Qi-dong ZHU Hui-dan CHENG Xin NIE Weidong CAO Jun NIE 《农业科学学报》2019,18(10):2381-2392
The double-rice cropping system is a very important intensive cropping system for food security in China. There have been few studies of the sustainability of yield and accumulation of soil organic carbon(SOC) in the double-rice cropping system following a partial substitution of chemical fertilizer by Chinese milk vetch(Mv). We conducted a 10-year(2008–2017) field experiment in Nan County, South-Central China, to examine the double-rice productivity and SOC accumulation in a paddy soil in response to different fertilization levels and Mv application(22.5 Mg ha~(–1)). Fertilizer and Mv were applied both individually and in combination(sole chemical fertilizers, Mv plus 100, 80, 60, 40, and 0% of the recommended dose of chemical fertilizers, labeled as F100, MF100, MF80, MF60, MF40, and MF0, respectively). It was found that the grain yields of double-rice crop in treatments receiving Mv were reduced when the dose of chemical fertilizer was reduced, while the change in SOC stock displayed a double peak curve. The MF100 produced the highest double-rice yield and SOC stock, with the value higher by 13.5 and 26.8% than that in the F100. However, the grain yields increased in the MF80(by 8.4% compared to the F100), while the SOC stock only increased by 8.4%. Analogous to the change of grain yield, the sustainable yield index(SYI) of double rice were improved significantly in the MF100 and MF80 compared to the F100, while there was a slight increase in the MF60 and MF40. After a certain amount of Mv input(22.5 Mg ha~(–1)), the carbon sequestration rate was affected by the nutrient input due to the stimulation of microbial biomass. Compared with the MF0, the MF100 and MF40 resulted in a dramatically higher carbon sequestration rate(with the value higher by 71.6 and 70.1%),whereas the MF80 induced a lower carbon sequestration rate with the value lower by 70.1% compared to the MF0. Based on the above results we suggested that Mv could partially replace chemical fertilizers(e.g., 40–60%) to improve or maintain the productivity and sustainability of the double-rice cropping system in South-Central China. 相似文献
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Jinglong LI Peng ZHANG Hongju LIU Wei REN Jinjing SONG Elizabeth RAO Eiki TAKAHASHI Ying ZHOU Weidong LI Xiaoping CHEN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1235-1240
Iron is involved in various physiological processes of the human body to maintain normal
functions. Abnormal iron accumulation in brain has been reported as a pathogenesis of
several neurodegenerative disorders and cognitive impairments. Hemojuvelin (HVJ) is a
membrane-bound and soluble protein in mammals that is responsible for the iron overload
condition known as juvenile hemochromatosis. Although iron accumulation in brain has been
related to neurodegenerative diseases, it remains unknown the effect of mutation of HVJ
gene on cognitive performance. In our studies, HJV(−/−) mice showed deficits in novel
object recognition and Morris water maze tests. Furthermore, the expression ration of
apoptotic marker Bax and anti-apoptotic marker Bcl-2 in the hippocampus and prefrontal
cortex showed higher levels in HJV(−/−) mice. Our results suggested that deletion of HJV
gene could increase apoptosis in brain which might contribute to learning and memory
deficits in mutant mice. These results indicated that HJV(−/−) mice would be a useful
model to study cognitive impairment induced by iron overload in brain. 相似文献
958.
高羊茅种子内生真菌的消毒方法 总被引:4,自引:1,他引:3
在高羊茅Festuca arundinacea组织培养中最常用的外植体是成熟种子,而种子中共生的半知菌亚门内生真菌Neotyphodium coenophialum使消毒较为困难,污染率高.为了研究温水处理对富含内生真菌的高羊茅种子发芽率、污染率和出愈率的影响,以不同温度(40,50,60℃)、不同时间(10,20,30min)的温水浸泡和次氯酸钠配合使用处理高羊茅种子,并进行发芽率试验和愈伤组织培养.经统计学分析发现,适用于富含内生真菌的高羊茅种子的最佳消毒组合为50℃温水浸泡10min,再经70%酒精处理5min,然后用次氯酸钠处理15min.消毒方法在保证较高种子发芽率的前提下,可降低种子污染率,提高出愈率.该消毒技术对于解决高羊茅因内生真菌造成的严重污染、出愈率低等现象有重要作用,并为高羊茅再生体系构建奠定重要的试验基础. 相似文献
959.
1营养水平公鸡不需要高钙饲料,含钙过高的饲料对公鸡肾脏有损伤,因此要求配专用公鸡料。高钙饲粮也可能是因为高钙与微量元素之间的拮抗作用,从而影响种公鸡对微量元素的吸收利用,出现继发性微量元素缺乏,特别是锰、铜、锌缺乏,导致种公鸡繁殖机能下降,而不同品种的种公鸡对其耐受性差异较大。用高钙饲粮(含钙3.823%)饲喂父母代公鸡, 相似文献
960.