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模糊隶属法对玉米苗期耐旱性的拟合分析 总被引:14,自引:1,他引:14
在略高于玉米萎蔫系数的干旱条件下,以出苗率和生物学产量耐旱系数之乘积为指标,测定了17个玉米自交系和10个杂交种的苗期抗旱性。并用模糊隶属法,以干旱胁迫下的胚芽鞘长度,出苗率,根重,生物学产量,脯氨酸含量,电导率和离体叶片保水力等指标对各品种耐旱性进行了拟合分析。结果表明,在略高于萎蔫系数的干旱条件下,以出苗率和生物学产量的耐旱系数之乘积为指标,可以准确鉴定玉米苗期的耐旱性,与耐旱性的综合评价拟合良好(相关系数r=0.914)。 相似文献
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水稻旱作对其生长量和经济产量的影响 总被引:11,自引:0,他引:11
1998~1999年,研究了水稻旱作条件下,不同生育时期受水分胁迫后对作物生长量的影响。结果表明:不同指标对水分胁迫时期的敏感性不一,植株高度对抽穗期水分胁迫最敏感;单株绿叶面积和单株地上部干重对幼穗分化后期水分胁迫最敏感;根系干重和根冠比对幼穗分化前期水分胁迫最敏感;幼穗分化后期水分胁迫对经济产量影响程度最大,无效分蘖期水分胁迫对产量影响程度最小。 相似文献
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Burkholderia plantarii , the pathogen of bacterial seedling blight of rice, was detected in paddy water. Its concentration rose in July and August.
The bacterial concentration in the paddy water was always higher along levees than at distances more than 5 m from levees.
Confirmed to be released into water when graminaceous weeds were immersed, B. plantarii survived for at least 4 days at 30°C. B. plantarii was splashed at least 30 cm upward by rain splash in the field. Harvested seeds, which had been sprayed with B. plantarii released from graminaceous weeds at the flowering stage, retained the bacteria. Bacterial seedling blight occurred when the
seeds were then sown in nursery boxes. These results indicated that graminaceous weeds growing on levees of paddy fields are
a source of infection of the disease and that rice seeds are infected through the paddy water.
Received 23 May 2002/ Accepted in revised form 1 September 2002 相似文献
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Buddhi Marambe Siril Wijesundara Kushan Tennakoon Dhammika Pindeniya Chandana Jayasinghe 《Weed Biology and Management》2002,2(2):79-83
The growth and development of Cuscuta chinensis Lam., and the effects of the holoparasite on the growth and yield of tomato ( Lycopersicon esculentum ), chilli ( Capsicum annuum ) and rice ( Oryza sativa ) were investigated in pot experiments under glasshouse conditions. 'Mature' and 'immature' seeds of C. chinensis showed 15 and 47% germination, respectively. The independent life duration of seedlings from 'immature' seeds was 6 days shorter than 'mature' seeds (19 days). Cuscuta chinensis formed haustoria on chilli and tomato, but not on rice seedlings. Infection with three C. chinensis seedlings per host plant reduced leaf area, dry weight, carbon and nitrogen content by 78–84% and 27–44% in tomato and chilli plants, respectively. Dry weight of C. chinensis was 0.63 g per pot in tomato, and 0.24 g per pot in chilli. Carbon and nitrogen content of C. chinensis was 0.189 and 0.028 g per pot, respectively, when grown with tomato. When it was grown with chilli, the carbon and nitrogen content of C. chinensis was 0.001 and 0.007 g per pot, respectively. Cuscuta chinensis reduced the fruit yield of tomato and chilli by 72 and 29%, respectively. The results indicated that tomato is a preferred host of C. chinensis compared with chilli, and rice is not preferred. In the host–parasite associations, C. chinensis suppressed growth and yield of chilli and tomato by diverting the elaborated products of metabolism of the hosts. 相似文献
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