【摘要】 玉米种子在吸收膨胀和主胚根开始伸长时对涝害最敏感,淹水2—4天可降低出苗率50%以上.高温、延长淹水期和增加淹水层均会明显加重涝害.受涝后幼苗生长弱,发育慢;根系受害程度重于地上部.早播和起垄播种有助于预防或减轻夏玉米的涝害.更多还原

【Abstract】 A simulation study was carried out in pot planting conditions to .determine the effects of waterlogging at the seedling stage on summer corn growth. The results indicat -ed that the most sensitive period of corn to waterlogging occurred from the inhibition (seed swellind) stage to the enlongation stage of radicles (2-3 days afterafter planting) . During this period, the germination rate decreased dy more than 50% after 2 days of flooding, The resistance of corn to waterlogging increased grasually after emergence, but the retarding effect on seedling growthstill remained significant. It mainly resulted in decreases of the length, volume and weight of roots , and the leaf area and dry weight per plant, and in increases of the number of withered and yellow leaves. Flooding also promote the early growth of secondary roots and enlarged the air space inside roots.The adverse effects of waterlogging on corn became greater and greater 2S the depth and duration of flooding increased. Flooded seedlings died 2 days after the whole plant was kept under water. Seedlings with leaves above water survived even after 3 days of flooding. It was found that high temperature during flooding could result in a more serious damage.更多还原