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131.
新型激活蛋白对多种作物种子发芽的影响 总被引:1,自引:0,他引:1
为探讨真菌源激活蛋白在促进种子发芽方面的效果,研究了不同浓度激活蛋白处理对多种作物种子的影响。试验结果表明,用2—3μg/mL的新型激活蛋白浸泡棉种6h,能显著提高种子的发芽势和发芽率。番茄和丝瓜种子分别用1μg/mL的蛋白浸种6h,能显著提高种子的发芽率。黄瓜种子用500倍和1000倍液都能显著提高种子的发芽率。 相似文献
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Summary Cold tolerance of common bean (Phaseolus vulgaris L.), runner bean (P. coccineus L.) and several bean lines was evaluated under artificial conditions. Seedlings were exposed to –6°C gradually, then to –12°C rapidly in the growth chamber with copper-constantan thermocouples attached to various parts of the plant. Seedling freezing curves with exotherms were then analyzed. Three basic parameters were measured: time required for exotherm to appear, temperature of the appearance of the exotherm and temperature rise caused by the exotherm. Exotherm appearance in beans was related to freezing injury and death of the seedlings. Exotherms of the common bean variety Bush Blue Lake 92 seedling recorded at the stem, primary leaf base, tip and petiole and true leaf appeared at the same time, however their shape was different. Exotherms of stem appeared at higher temperature than those of primary leaves. Their shapes always followed the same pattern. Beans with cold tolerance were found to produce exotherms later than susceptible ones. Exposing 3 weeks old bean seedlings to 12°C delayed the time of exotherm appearance in the cold susceptible cultivar Bush Blue Lake 92. Some plants survived 2 hours exposure to –6°C in the growth chamber. 相似文献
137.
Seed presoaking improves wheat germination under marginal moisture conditions. The duration of seed presoaking was studied at The University of Arid Agriculture, Rawalpindi, using 10 wheat varieties. Seed presoaking beyond 12 h does not improve germination further, and beyond 21 h, germination rate is drastically reduced. 相似文献
138.
Darryl G. Stout 《Journal of Agronomy and Crop Science》1998,181(4):263-266
Experiments were conducted to determine if diurnal temperature variation could be used to prime cicer milkvetch ( Astragalus cicer L.) seed and thereby shorten the time for seed germination. For untreated cicer miikvetch seed at constant 20°C, 50% of the seeds germinated in 8.2 days and 90% of the seeds germinated in 10.5 days. In contrast, seed that was first primed for 7 days with a diurnal temperature variation (35 (8h)/5 (16h) °C) had values of 1.9 days and 3.3 days, respectively. A second experiment evaluated priming of seed in bulk to test if a procedure might be developed that could be scaled up to prime commercial quantities of seed. A bulk sample of seed was soaked in water for 5h at room temperature and then kept in a high humidity atmosphere during 7 days of priming at 35/5°C. Hydrated seed from the bulk sample had 50% germination in 2.7 days and 90% germination in 5.3 days. When the bulk sample was dried for 8 days at room temperature, the benefit of priming on shortening germination time was retained. It is likely that diurnal temperature priming could be adapted to large volumes of seed. 相似文献
139.
种子形状参数检测的计算机图象处理技术 总被引:18,自引:0,他引:18
设计了采用计算机图象处理技术检测形状特征参数的实用算法,开发了对种子进行基本形状参数测量的计算机图象处理系统,实际测试表明,系统运行稳定,测量速度快,精度高,适合同时分析多个物体的特征参数。 相似文献
140.
A field experiment was conducted for 2 years to investigate the effects of deficit irrigation, nitrogen and plant growth minerals on seed cotton yield, water productivity and yield response factor. The treatment comprises six levels of deficit irrigation (Etc 1.0, 0.9, 0.8, 0.7, 0.6 and 0.5) and four levels of nitrogen (80, 120, 160 and 200 kg N ha−1). These were treatments superimposed with and without plant growth mineral spray. Furrow irrigation treatments were also kept. Cotton variety Ankur-651 Bt was grown during 2006 and 2007 cotton season. Drip irrigation at 1.0 Etc saved 26.9% water and produced 43.1% higher seed cotton yield over conventional furrow irrigation (1.0 Etc). Imposing irrigation deficit of 0.8 Etc caused significant reduction in seed cotton yield to the tune of 9.3% of the maximum yield. Further increase in deficit irrigation from 0.7 Etc to 0.5 Etc significantly decreased seed cotton yield over its subsequent higher irrigation level. Decline in the yield under deficit irrigation was associated with reduction in number of bolls plant−1 and boll weight. Nitrogen at 200 kg ha−1 significantly increased mean seed cotton yield by 36.3% over 80 kg N ha−1. Seed cotton yield tended to increase linearly up to 200 kg N ha−1 with drip Etc 0.8 to drip Etc 1.0. With drip Etc 0.6-0.5, N up to 160 kg ha−1 provided the highest yield, thereafter it had declined. Foliar spray of plant growth mineral (PGM) brought about significant improvement in seed cotton yield by 14.1% over control. The water productivity ranged from 0.331 to 0.491 kg m−3 at different irrigation and N levels. On pooled basis, crop yield response factor of 0.87 was calculated at 20% irrigation deficit. 相似文献