水稻穗分化期不同土壤水势叶温及生理性状变化

摘要

以水稻开粳1号为材料,研究不同土壤水势梯度下不同胁迫时间及复水处理对叶片温度、叶片生理指标的影响.结果表明,在白天不同测定时间内,各土壤水分胁迫下,随土壤水势的降低,叶片温度升高,但在试验处理梯度内,叶温均低于气温,各处理复水7 d后叶温基本相同,且仍低于气温;在控水期间叶绿体色素含量降低,复水7 d后叶绿体色素含量增加,轻度水分胁迫(-0.02～-0.05MPa)处理高于控水14 d水平,重度水分胁迫(-0.06～-0.08MPa)高于控水7 d水平,表现为补偿现象,15:00时叶温与叶绿素a呈极显著负相关;丙二醛(MDA)含量在轻度水分胁迫下先降低,复水后升高,但仍与控水初期水平相当,在重度水分胁迫下先升高,复水后降低,但仍高于控水初期,13:00时丙二醛含量与叶温呈极显著正相关,14:00时呈显著正相关.%Japonica 1 was used to study leaf temperature and leaf physiological indicators under different time and rehydration of different water stress in different soil water gradient. The results showed that with lowering of soil water potential. the leaf temperature increased under different soil moisture stress during the daytime, but leaf temaperature was lower than air temperature. Leaf temperatures of all treatments were the same aftter 7 days' rehydration and still lower than air temperature. The chlorophyll content decreased during controlling the water, but it increased after 7 davs' rehvdration with mild water stress treatment (-0.02～-0.05MPa) higher than controlling water for 14 days, and severe water stress treatment (-0.06～-0.08MPa) higher than controlling water for 7 days. This showed a kind of' compensation phenomenon. Leaf temperature was very significantly negatively correlated with chlorophylla's content at 15:00 pm. Under mild water stress, malondialdehyde (MDA) content decreased. but increased after rehydration and kept at the same level at the beginning of controlling water. Under severe water stress. malondialdehyde content increased. but decreased after rehydration and still higher than the level at the beginning of controlling water. Malondialdehyde content showed highly significant positive correlation with leaf temperature at 13:00 pm and significant positive correlation at 14:00 pm.