分蘖期淹水胁迫对早稻生长发育及产量构成的影响

Effects of Waterlogging Stress on Growth and Yield of Early Rice at Tillering Stage

为了探明分蘖期不同淹水深度和淹水历时对早稻生长发育和产量形成的影响,于2018年4-7月,以陆两优996为试验材料采用盆栽模拟受淹的方法,开展了早稻分蘖期不同淹水深度和淹水历时的试验研究,设定CK(不受淹处理)、H1(20 cm)、H2(30 cm)、H3(40 cm)3种不同淹水深度和D1(1 d)、D3(3 d)、D5(5 d)、D7(7 d)4种不同淹水历时处理,每处理重复3次。结果显示,分蘖期受到淹水胁迫后会抑制早稻分蘖数的增长和促进株高的增长,且随着淹水深度和历时增加水稻分蘖增长受到抑制更严重,株高较对照间的差异会越显著;淹水胁迫对早稻剑叶SPAD值影响表现为受淹开始前1 d处理间差异均不显著,水稻受淹结束后剑叶中SPAD值会显著降低,等到受淹结束后7 d时,剑叶中SPAD值逐渐恢复到正常水平;早稻分蘖期受到淹水胁迫后地上部分干物质积累量会降低,随着淹水深度和淹水历时增加与CK间差异越显著,且不同部位中对穗部位干物质积累影响最大;在产量构成方面表现为早稻分蘖期受到淹水胁迫后有效穗数、结实率和实际产量的显著降低,与SFW(淹水累计深度)之间相关系数分别达到-0.914^**、-0.983^**和-0.942^**。受淹水胁迫影响最大的为实际产量,所有处理与CK间实际产量差异均达到显著水平(p<0.05),并且随着淹水深度和历时增加与CK间差异越大,回归分析表明可以以SFW(淹水累计深度)为自变量构建早稻分蘖期淹水胁迫后实际产量预测模型。

In order to verify the effects of different flooding depth and flooding duration on growth and yield of rice during tillering stage,the experiment of different flooding depth and flooding duration during tillering stage was carried out in April-July of 2018 by using pot test method to simulate flooding,in which Lu Liangyou 996 was taken as the test material.CK(no flooding treatment),H1(20 cm),H2(30 cm)and H3(40 cm)were set for different flooding depth,and D1(1D),D3(3D),D5(5d)and D7(7d)were set for different flooding duration treatment.Each treatment was repeated for 3 times.The results showed that the growth of tiller number and plant height of early rice were inhibited and promoted by flooding stress at tillering stage,and the growth of tiller was more seriously inhibited with increasing depth and duration of flooding,and the plant height difference was more significant than that of control group;the effect of flooding stress on SPAD value of early rice flag leaves showed that the difference between treatments was not significant 1 day before the beginning of submersion,SPAD value in rice flag leaves decreased significantly after the end of submersion,and gradually returned to the normal level 7 days after the end of submersion.At early rice tillering stage,the dry matter accumulation of above-ground part would decrease under the stress of flooding,the difference between them and CK was more significant with the increase of depth and duration of flooding,and the dry matter accumulation of panicle part was most affected in different parts.In terms of yield composition,effective panicle number,seed setting rate and actual yield decreased significantly after flooding stress at early rice tillering stage,correlation coefficients between them and SFW(cumulative depth of flooding)reached-0.914^**,-0.983^**and-0.942^**respectively.The actual yield was the most affected by flooding stress,and the actual yield difference between all treatments and CK reached a significant level(p<0.05),and with the increase of depth and duration of flooding,the difference between THEM was larger.The regression analysis showed that SFW(cumulative depth of flooding)could be used as independent variable to construct the actual yield prediction model after flooding stress at early rice tillering stage.