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11.
Septoria leaf blotch progresses rapidly, leading to the development of Zymoseptoria titici forms resistant to fungicides. Cephalosporium stripe is caused by Cephalosporium gramineum. The aim of this study was to evaluate the effectiveness of selected pesticides in limiting the symptoms of both diseases on winter wheat leaves, and to determine their influence on grain yield and the content and composition of protein fractions in wheat kernels. Propiconazoles were most effective in inhibiting the development of Septoria leaf blotch (symptoms were reduced from 54.7% to 78.6%). Strobilurins were less effective due to the presence of isolates with the G143A mutation. Symptoms of Cephalosporium stripe were rarely observed, and protective treatments did not reduce their severity. The highest content of grain protein (14.81%) was found in plants most intensely protected with the fungicides containing fenpropimorph, pyraclostrobin and epoxiconazole. The principal component analysis revealed that the plant protection method influenced the grain protein profile. The accumulation of HMW glutenins and α/β gliadins was mutually interrelated and higher in high-input treatments; control grain was characterized by close relationships between ω-gliadins, LMW glutenins, albumins and globulins, whereas low-input treatments influenced mostly γ-gliadins. 相似文献
12.
为初步了解硅藻土对储粮害虫的防治效果以及与害虫磷化氢抗性发生发展的关系, 本研究采用直接拌粮法(设置剂量梯度为0?0.2?0.4?0.6 g/kg和 0.8 g/kg)测定硅藻土对赤拟谷盗?杂拟谷盗?锈赤扁谷盗?谷蠹?玉米象的防治效果, 以及磷化氢抗性杂拟谷盗(抗性倍数为 2.3~144.7)对硅藻土的敏感性差异; 除此之外, 本研究还分析了0.4 g/kg硅藻土在 4 种粮食(小麦?玉米?大豆?稻谷)中对赤拟谷盗的杀虫效果?研究结果表明:一定剂量(0.2~0.8 g/kg)的硅藻土均能够在一定时间内有效杀死上述 5种储粮害虫, 不同储粮害虫对硅藻土的敏感性存在显著差异(P<0.05), 其中杂拟谷盗对硅藻土的耐受性最强, 玉米象对硅藻土最为敏感?除个别品系外, 不同磷化氢抗性品系的杂拟谷盗对硅藻土的敏感性不存在显著差异(P>0.05), 且与磷化氢抗性无关; 硅藻土在不同粮食中对害虫的作用效果存在显著性差异(P<0.05)(处理 7 d后, 死亡率为 13%~98%), 其中在大豆中对赤拟谷盗的杀虫效果最强, 在玉米中对其作用效果不明显?因此本研究得出结论:硅藻土对主要储粮害虫均具有一定的防治作用, 且对抗磷化氢的杂拟谷盗具有良好的致死效果?因此, 硅藻土具备成为储粮害虫防治及其磷化氢抗性治理药剂的潜力? 相似文献
13.
目的 探明不同类型水稻品种产量和氮素吸收利用对FACE(大气CO2浓度增高)响应的差异。方法 以常规粳稻、杂交籼稻、常规籼稻共6个品种为供试材料,研究FACE对不同类型水稻产量、氮素吸收利用的影响。结果 1)FACE处理极显著提高了水稻产量,平均增加24.17%, 常规籼稻增幅最大,FACE和对照均以杂交籼稻最高;2)FACE处理显著增加了单位面积穗数,常规粳稻增幅最大,并显著增加了杂交籼稻和常规籼稻每穗粒数;3)FACE处理显著提高了成熟期吸氮量和氮素籽粒生产效率,成熟期吸氮量平均增加21.23%,杂交籼稻增幅最大, FACE和对照均以常规籼稻最高;氮素籽粒生产效率平均增加7.33%,杂交籼稻增幅最大,FACE和对照均以杂交籼稻最高。成熟期吸氮量对产量促进作用略大于成熟期氮素籽粒生产效率;4)FACE处理降低了植株含氮率,成熟期平均下降0.105个百分点,常规粳稻降幅最大。FACE处理极显著提高植株干物质量,成熟期平均增加23.95%,常规籼稻增幅最大;FACE处理显著提高常规籼稻和杂交籼稻成熟期单穗吸氮量,分别增加10.79%、13.93%,但常规粳稻下降了9.60%;FACE处理显著提高了成熟期群体吸氮强度,平均增加22.29%,杂交籼稻增幅最大。FACE处理对水稻全生育期天数无显著影响;FACE处理显著提高茎鞘、叶片、穗各器官吸氮量,叶片增幅最大,平均增加51.86%,杂交籼稻增幅最大;FACE处理显著提高了不同生育阶段吸氮量,抽穗-成熟阶段增幅最大,平均增加108.90%,杂交籼稻增幅最大;5)植株干物质量、单穗吸氮量、吸氮强度、穗吸氮量、抽穗-成熟阶段吸氮量对成熟期总吸氮量的促进作用分别大于植株含氮率、单位面积穗数、生育天数、茎鞘叶吸氮量、移栽-分蘖和分蘖-抽穗阶段吸氮量;6)FACE处理显著提高了氮肥偏生产力,降低了每百千克籽粒需氮量,前者平均增加24.16%,常规籼稻增加最多;后者平均降低4.7%,常规籼稻降幅最大。结论 FACE处理可显著提高水稻产量和氮素吸收利用效率,但品种间差异较大。 相似文献
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15.
The effect of heat stress on the components of grain weight was analysed in wheat ( Triticum aestivum L.) varieties differing in grain weight stability. The wheat varieties PBW154, Sonalika and Hindi62 were raised in the field (New Delhi, India; 77°12' E, 28°40' N, 228.6 m a.s.l.) at three dates of sowing: 19 November 1992 (DOS I), 14 December 1992 (DOS II) and 18 January 1993 (DOS III). The late-sown crop (DOS III) experienced 6–8 °C warmer temperatures during grain development than the crop sown at the normal time (DOS I). The heat susceptibility index (S) revealed that grain weight was less susceptible to heat in Sonalika and PBW154 than in Hindi62. Heat stress reduced both the grain growth duration (GGD) and the grain growth rate (GGR). The grain weight reduction in PBW154 and Sonalika was mainly due to a reduction in GGR, while that of Hindi62 was due to a reduction in GGD. In vivo studies on starch and protein synthesis in excised endosperm at 15, 25 and 35 °C revealed that both processes were more thermotolerant in Hindi62 than in PBW154. The grain starch content was stable in Hindi62 while that in PBW154 was significantly reduced under heat stress. The grain nitrogen content at maturity increased in both varieties under heat stress. It was concluded that the heat susceptibility of grain weight in Hindi62 was mainly due to a reduction in GGD, although GGR, starch and protein synthesis were more thermotolerant in developing grains of Hindi62 than in those of PBW154. 相似文献
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18.
T. Sivakumar Virendranath & G. C. Srivastava 《Journal of Agronomy and Crop Science》2001,186(1):43-46
Grain yield and yield components (grains per ear, grain weight, 1000-grain weight, ear weight, ear seed ratio and dry matter partitioning between ear and seed) were examined in a wheat genotype (PBW-343) with well-filled grains and a Triticale genotype (DT-46) with poorly filled grains (showing grain shrivelling) grown in pots. Six days after anthesis (DAA), benzyladenine (BA) @2 µg ear−1 and abscisic acid (ABA) @4 µg ear−1 were injected at the base of the mother shoot ear in both species. It was observed that, in both wheat and Triticale , BA increased the grain weight, grain number and partitioning of dry matter between ear and seed, whereas ABA decreased the grain weight, grain number and dry matter partitioning between ear and seed. However, these decreases were slower in Triticale than in wheat. BA treatment increased the grain dry matter accumulation, which in turn resulted in better filling of grains and increased the grain weight in both wheat and Triticale . The average grain weight of Triticale was lower than that of wheat. Thus, it appears that variation in grain weight between wheat and Triticale might be due to different availabilities of growth-promoting phytohormones such as cytokinins and assimilates. 相似文献
19.
谷物冷却机回风利用与节能 总被引:1,自引:0,他引:1
分析了谷物冷却机采用回风型冷却的节能原理及优点,回风型冷却具有重要的节能意义。 相似文献
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