孕穗期水分胁迫对水稻部分生理特性与产量补偿效应的研究

[目的]在孕穗期对水稻进行不同程度水分胁迫后复水,探讨水稻生理特性与产量补偿效应,以期为提高水稻水分利用率及其抗旱性提供依据.[方法]采用盆栽试验,对5个水稻品种在孕穗期分别设置3个不同水分胁迫处理,于复水后,每隔6d采样分析生理指标等.[结果]随着复水天数的增加,不同水稻品种轻旱处理B叶片的水势、SPAD、净光合速率增加速度较快,可溶性糖的补偿效应大于重旱处理C;经过水分胁迫处理的水稻茎流速度均下降.对于产量构成因素,水分胁迫处理的每株穗数和每株实粒数均有下降,每株粒数下降值受水分胁迫程度影响明显;除D优363外,其他品种结实率均以处理B最高;与对照处理A相比,受水分胁迫的两个处理B、C的千粒重和单株穗重均有所下降.[结论]水稻在孕穗期经过不同程度的水分胁迫,恢复常规管理后,受到轻度水分胁迫处理的水稻部分生理特性以及产量性状均获得较好的补偿效应.

Effects of water stress on partial physiological characteristics and yield compensation in rice at booting stage

[Objective]The physiological characteristics and yield compensation effects of rice at booting stage were studied after water was added when rice suffered water stress to provide references for improving rice water utilization effi- cacy and its drought resistance. [Method]The pot experiments with 5 rice varieties under 3 different treatments of water stress were conducted to study physical signs every 6 days after water-recovery. [Result]Along with the increase of water- recovery, the water potential, SPAD and Pn values of treatment B （light drought） increased fast, and its compensation ef- fects of the soluble sugar content were better than those of treatment C （severe drought）. All sap flow speed fell. As for the yields and yield integrants, panicles per plant and spikelets per panicle decreased with water stress degree, and especially the values of spikelets per panicle were greatly influenced by water stress. Seed setting rate in treatment B was the largest in every variety except Diyou363. The 1000-grain weight and single plant weight in treatments B and C were both lower than those of the control A. [ Conclusion ] Once regular management was resumed after rice underwent water stress at booting stage, many characteristics and yield traits in rice had witness favorable compensation effects in light water stress treatments.