水分胁迫及复水对马铃薯生长发育及产量的影响

Effects of water stress and rewatering on potato growth and yield

于2019年在遮雨棚内采用随机区组试验,以常年时序降水量为对照(CK),设置马铃薯苗期(W1S)、块茎形成期(W2S)、块茎膨大期(W3S)、淀粉积累期水分胁迫(W4S)以及胁迫20 d后的复水处理,监测不同水分环境对马铃薯的农艺性状、SPAD值与冠层光谱反射率、耗水量以及产量的影响。结果表明,各时期的水分胁迫导致马铃薯生长被抑制了4.25%~83.48%,复水后抑制作用减弱,降为3.67%~31.35%;水分胁迫导致马铃薯叶片SPAD值上升了0.20%~30.04%,相应冠层750~1150nm波段光谱反射率降低,而在1950~2450nm波段反射率升高。水分胁迫后各处理的水分利用效率降低了4.34%~40.15%,复水后降为3.98%~30.54%。水分胁迫使马铃薯经济产量较CK降低了25.59%~81.49%;复水后经济产量较CK降低了12.89%~41.48%。马铃薯经济产量(干质量)与农田耗水量、生育期累积叶面积呈显著线性正相关;叶片SPAD值及冠层高光谱反射率可作为马铃薯水分胁迫程度的田间诊断指标。

In 2019,a randomized block test in the canopy with the annual precipitation as control(CK)was set up to monitor the effects of different water environments on agronomic traits,SPAD value,canopy spectral reflectance,water consumption,and yield of potato.The potato seedling stage(W1S),tuber formation stage(W2S),tuber expansion stage(W3S),and starch and accumulation period were set for water stress(W4S)and rewatering treatment after 20 days of stress.The results showed that the growth of potato was inhibited by 4.25%~83.48%under water stress,and the inhibition decreased to 3.67%~31.35%after rehydration.The SPAD value of potato leaves increased by 0.20%~30.04%under water stress,and the spectral reflectance of 750~1150 nm in canopy decreased,while that of 1950~2450 nm increased.After water stress,water use efficiency of all treatments decreased by 4.34%~40.15%,and decreased to 3.98%~30.54%after rewatering.Compared with CK,the economic yield of potato decreased by 25.59%~81.49%under water stress and by 12.89%~41.48%after rewatering.The economic yield(dry weight)of potato was positively correlated with water consumption and accumulated leaf area in growth period,and SPAD value and hyperspectral reflectance of canopy could be used as field diagnostic indexes of water stress degree of potato.