Tolerance to excess moisture in maize (Zea mays L.): susceptible crop stages and identification of tolerant genotypes
Tolerance to excess moisture in maize (Zea mays L.): susceptible crop stages and identification of tolerant genotypes
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DOI：
10.1016/j.fcr.2004.03.002
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发表时间：
2004-12
影响因子：
5.8
通讯作者：
P. H. Zaidi;S. Rafique;P. Rai;N. Singh;G. Srinivasan
中科院分区：
文献类型：
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作者：
P. H. Zaidi;S. Rafique;P. Rai;N. Singh;G. Srinivasan
夏雨季的水分过多（内涝）是制约玉米生产的主要因素之一。在东南亚的一大片地区。鉴定和开发能够承受胁迫条件的基因型可能是一种理想的和负担得起的方法，适合这些地区资源贫乏的玉米种植农民。我们试图确定最敏感/关键作物阶段（S）的玉米过量水分胁迫，并发展筛选技术和选择策略，鉴定种质耐过量水分胁迫。结果表明，在苗期（V2）、齐穗期（V7）、抽雄期（VT）和乳熟期（R1）4个生育期中，V2最敏感，V7次之。筛选技术（杯法）的开发/标准化，并被认为是一种有效的技术，大规模筛选玉米基因型对过量土壤水分胁迫。使用该技术筛选种质，然后在V7生长阶段（第七片叶可见）进行田间评价。土壤水分胁迫严重影响小麦的生长发育和生化指标，影响开花和吐丝，最终导致籽粒发育不良和产量下降。然而，显着的变异性之间的基因型研究。具有茎组织中碳水化合物积累良好、气孔导度适中、ASI <5天、根孔隙度高和早期支撑根发育能力的基因型已被发现对由过量土壤水分条件引起的缺氧/缺氧具有良好的耐受性。
Excess moisture (water-logging) during the summer–rainy season is one of the major production constraints for maize (Zea mays L.) in a large area of Southeast Asia. Identification and development of genotypes capable of withstanding the stress conditions could be an ideal and affordable approach suitable for resource poor maize-growing farmers of such areas. We attempted to identify the most susceptible/critical crop stage(s) of maize for excess moisture stress, and to develop a screening technique and selection strategies for identification of germplasm tolerant to excess moisture stress. Among the four crop stages, i.e. early seedling (V2), knee-high (V7), tasseling (VT) and milk stage (R1), V2 was found to be highly susceptible, followed by the V7 stage. A screening technique (cup method) was developed/standardized, and was found to be an efficient technique for large-scale screening of maize genotypes against excess soil moisture stress. Germplasm was screened using this technique followed by field evaluation at the V7 growth stage (seventh leaf visible). Excess soil moisture stress severely affected various growth and biochemical parameters, impaired anthesis and silking, and eventually resulted in poor kernel development and yield. However, remarkable variability was found among the genotypes studied. Genotypes with good carbohydrate accumulation in stem tissues, moderate stomatal conductance, <5 days ASI, high root porosity, and early brace root development ability have been found to have good tolerance against the hypoxia/anoxia caused by excess soil moisture conditions.