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991.
幼苗期小麦热激蛋白的诱导研究(英文) 总被引:4,自引:0,他引:4
高温是小麦产量提高的一个重要限制因素,小麦受到高温胁迫时会产生一系列热激蛋白来适应这种逆境,不同发育阶段的热激蛋白存在差异,不同抗热作物品种中热激蛋白也存在差异,因此,研究抗热性不同的小麦品种中热激蛋白差异对小麦耐热性的研究具有重要的理论意义与实践意义。该实验利用SDS-PAGE电泳技术对2种不同的小麦品系在34.37、40℃下处理1~7h产生的热激蛋白进行研究,发现其可溶性蛋白电泳图谱与常温下的有区别,其中新蛋白的出现说明高温能够诱导新蛋白。71321-9中发现的3种新蛋白的分子量分别为97.4kD、49kD、37kD,另外还发现3种蛋白质含量明显升高,这3种蛋白质的分子量范围在17~66kD。71321-4小麦中发现了2种新增热激蛋白(37kD和29kD)及1种蛋白质的含量明显增加。这些蛋白可能与小麦幼苗抗热性有关,其含量的增加能够提高幼苗的抗热性。 相似文献
992.
浙江省水稻品种抗稻曲病自然诱发鉴定初步研究 总被引:5,自引:0,他引:5
在浙江省金华县稻曲病重发病区,对113个水稻品种进行了田间自然诱发抗性鉴定。结果表明:以稻曲病平均病级(X)为指标,X=0级、0级X≤Ⅰ级、Ⅰ级X≤Ⅱ级、Ⅱ级X≤Ⅲ级、Ⅲ级X≤Ⅳ级、Ⅳ级X≤Ⅴ级的品种数分别占品种总数的33.62%、20.35%、15.92%、8.84%、13.27%和7.96%。常规籼稻、常规粳稻、杂交籼稻和杂交粳稻,不发病或轻发病(平均病级小于Ⅰ级)的发生频率分别为100%、66.67%、54.04%和0%;重发病(平均病级大于Ⅲ级)的发生频率分别为0%、4.16%、20.26%和90.00%;粳稻发病明显重于籼稻,杂交稻明显重于常规稻,杂交粳稻发病最重。 相似文献
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Rhizoctonia black scurf is an economically important disease of potatoes in Tunisia and around the world. It reduces the quality and yield of potatoes and has become an important impediment for export of potatoes, especially to Europe. The information on comparative susceptibility of potato cultivars will help the growers make informed decisions regarding the management of this disease. The eleven potato cultivars used in this study showed a range of susceptibility reactions to Rhizoctonia solani but none of these was completely resistant to the disease. The Spunta variety showed the least percentage of infection of progeny tubers by R. solani sclerotia at harvest, while the varieties Nicola, Santana, Labadia, Liseta and Tango showed a high percentage of infection of progeny tubers. Seed treatment using fungicides, presently registered in Tunisia, are not effective in controlling the disease to growers’ satisfaction. Field experiments conducted to evaluate the efficacy of two newly introduced fungicides pencycuron (Monceren®) and azoxystrobin (Amistar®) showed that they were effective for the control of the disease. Seed potatoes treatment and in-furrow application of azoxystrobin consistently provided superior protection in two years of experimentation. 相似文献
996.
Yield formation and tillering dynamics of direct-seeded rice in flooded and nonflooded soils in the Huai River Basin of China 总被引:1,自引:0,他引:1
Jing Yan Jun Yu Guang Can Tao Jan Vos B.A.M. Bouman Guang Hui Xie Holger Meinke 《Field Crops Research》2010
Water shortage in the Huai River Basin prompts farmers to adopt water-saving technologies such as direct-seeded nonflooded or aerobic rice. Different cultivation practices impact on tiller growth and development. Improved insight into tiller dynamics is needed to increase yield in these production systems. We conducted field experiments with four direct-seeded rice varieties under flooded and nonflooded conditions in Mengcheng county, Anhui province, in 2005–2006. The soil water content in the nonflooded treatment varied between saturation and field capacity. Yields in nonflooded soil ranged from 3.6 to 4.7 t ha−1, and did not differ significantly from yields in flooded soil that ranged from 3.6 to 5.1 t ha−1. Variety had a significant effect on biomass, yield, panicle number, spikelet number, grain weight, and grain filling percentage. Panicle number was the main factor limiting yield, resulting from a low tiller emergence frequency and a low fraction of productive tillers in both the flooded and the nonflooded soils. On average, the panicle number was 159–232 m−2, including 34–167 productive tillers per m2 for all the varieties under the two water regimes. The contribution of productive tillers to yield varied between 7% and 47%. There were two peaks of tillers that contributed to yield, one at the low (4th or 5th) and one at the high (10th or 11th) phytomer orders. Frequencies of tiller emergence at most phytomer orders were higher in the flooded soil than in the nonflooded soil. There were no significant differences in frequencies of productive tiller emergence and contributions to yield from tillers between the soil water regimes for three of the four tested varieties. To increase yield in direct-seeded nonflooded rice production systems, both the tiller emergence frequency and the fraction of productive tillers should increase through breeding, improved crop management, or a combination. 相似文献
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品种与地域因素对谷子中Fe、Zn、Mg和Se元素含量影响的研究 总被引:1,自引:0,他引:1
对5个地域(石家庄、衡水、济南、沧州、郑州)分别种植的7个谷子品种(冀谷19、206058、200131、K492、济0515、沧344、安04-4783)共计35份谷子样品进行了4种矿物质元素(Fe、Zn、Mg、Se)含量的分析检测。结果表明:各个品种和各个地域的谷子中Fe、Zn、Mg和Se含量均有一定波动,尤其是Zn和Se含量变幅较大,说明品种和地域因素对谷子中矿物质元素含量均具有一定影响。双因素方差分析结果表明:Fe含量受品种因素影响差异显著(P=0.046 6),受地域因素影响差异极显著(P=0.00);Zn含量受品种与地域因素影响均不显著(P=0.990 1,P=0.531 4);Mg含量受品种品系影响差异显著(P=0.017 6),受地域因素影响差异不显著(P=0.655 8);Se含量受品种因素影响差异不显著(P=0.545 7),受地域因素影响差异极显著(P=0.00)。通过改善育种手段,可以实现富Fe和Mg谷子品种的选育;通过栽培管理中补充相应肥料等措施,可以提高谷子中Fe和Se元素的含量。 相似文献
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