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91.
马铃薯晚疫病是马铃薯生产中的重要病害,是影响马铃薯产量和品质的重要因素之一,在云南春作马铃薯上普遍发生,且危害较重,给当地马铃薯产业带来了巨大的经济损失。为减轻马铃薯晚疫病对马铃薯生产造成的损失,试验研究了11种药剂7种药剂组合(包衣剂+保护剂+治疗剂)通过播种期种薯包衣,现蕾期叶面喷施一次保护剂,发病初期和发病中期叶面各喷一次治疗剂的方法防治马铃薯晚疫病。结果表明,药剂组合种薯包衣+甲霜·锰锌+氟吡菌胺·霜霉威的防治效果最好,防治效果达到60.99%,增产率176.28%,增效率152.27%;其次是种薯包衣+霜脲·锰锌+氟吡菌胺·霜霉威组合,防治效果达到60.15%,增产率173.20%,增效率150.55%。这2个药剂组合对马铃薯晚疫病均有极显著的防治效果,增产增效明显。 相似文献
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利用东北农作区58个气象站点1961—2010年的逐日气象数据,基于Simulation of Evapotranspiration of Applied Water(SIMETAW)模型分析气候变化背景下东北农作区春小麦生育期内作物需水量(Crop evapotranspiration,ETc)和灌溉需要量(Evapotranspiration of applied water,ETaw),以及典型站点春小麦的灌溉需求指数(Irrigation demand index,IDI)的时空变化特征。结果表明:近50年来,东北农作区日平均温度呈显著上升趋势,平均降水量下降趋势不明显,平均太阳辐射及作物蒸散量呈显著下降趋势。春小麦生育期作物需水量和灌溉需要量呈下降趋势,其分布均表现为西多东少。50年来春小麦作物生育期需水量下降主要集中于松辽及兴安岭南部地区,东部地区变化趋势不明显;生育期灌溉需要量下降集中于松辽及兴安岭地区,三江平原地区略有增加,长白山地区多年保持平稳。 相似文献
94.
S. Narayanan P. V. V. Prasad A. K. Fritz D. L. Boyle B. S. Gill 《Journal of Agronomy and Crop Science》2015,201(3):206-218
High temperature is a major environmental factor that limits wheat (Triticum aestivum L.) productivity. Climate models predict greater increases in night‐time temperature than in daytime temperature. The objective of this research was to compare the effects of high daytime and high night‐time temperatures during anthesis on physiological (chlorophyll fluorescence, chlorophyll concentration, leaf level photosynthesis, and membrane damage), biochemical (reactive oxygen species (ROS) concentration and antioxidant capacity in leaves), growth and yield traits of wheat genotypes. Winter wheat genotypes (Ventnor and Karl 92) were grown at optimum temperatures (25/15 °C, maximum/minimum) until the onset of anthesis. Thereafter, plants were exposed to high night‐time (HN, 25/24 °C), high daytime (HD, 35/15 °C), high daytime and night‐time (HDN, 35/24 °C) or optimum temperatures for 7 days. Compared with optimum temperature, HN, HD and HDN increased ROS concentration and membrane damage and decreased antioxidant capacity, photochemical efficiency, leaf level photosynthesis, seed set, grain number and grain yield per spike. Impact of HN and HD was similar on all traits. Greater impact on seed set, grain number and grain yield per spike was observed at HDN compared with HN and HD. These results suggest that HN and HD during anthesis cause damage of a similar magnitude to winter wheat. 相似文献
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Unpredictable temperatures and rainfall associated with climate change are expected to affect wheat (Triticum aestivum L.) production in various countries. The development of climate-resilient spring wheat cultivars able to maintain grain yield and quality is essential to food security and economic returns. We tested 54 CIMMYT spring bread wheat genotypes, developed and/or released over a span of 50 years, in the field for two years under optimum sowing dates, as well as using two delayed sowing dates to expose crops to medium and severe heat-stress conditions. The grain yield and yield components were severely affected as the heat-stress increased. Two contrasting groups of 10 lines each were identified to determine the effect of heat-stress on bread-making quality. The first set included entries that produced high yields in optimal conditions and maintained higher yields under heat-stress (superior-yielding lines), while the second set included genotypes that did not perform well in the environment with high temperature (inferior-yielding lines). We identified genotypes exhibiting bread-making quality stability, as well as the quality traits that had higher correlation with the loaf volume in the environment without stress and under heat-stress. Of all the quality traits tested, dough extensibility (AlvL) and grain protein content had a significant influence in heat-stress adaptation. Most of the lines from the superior-yielding group were also able to maintain and even improve quality characteristics under heat-stress and therefore, could be used as parents in breeding to develop high-yielding and stable quality wheat varieties. 相似文献
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为了预测景泰绿洲春小麦(Triticum aestivum)、燕麦(Avena sativa)、黑麦(Secale cereale)的产草量和营养品质,通过田间试验,测得牧产草量、株高和分蘖,室内测定粗蛋白、粗脂肪、中性洗涤纤维、酸性洗涤纤维、粗灰分和可溶性碳水化合物,分析各指标之间的相关性。结果表明,收获干草的3种小谷物分蘖和株高均与可溶性碳水化合物之外其它5个营养指标存在显著相关性(P0.05),模拟轮牧的春小麦和黑麦株高与营养指标均无相关性(P0.05),燕麦和黑麦的分蘖与6个营养指标均呈显著相关(P0.05)。建立了根据株高预测产草量和营养品质的模型、用分蘖预测牧草营养品质的模型、用产草量预测牧草营养品质的模型、用分蘖和产草量两个因子综合预测营养品质的模型。经过与实测值对比,各预测模型的准确性均较高。 相似文献
100.