不同灌溉模式对水稻抗倒伏能力影响的试验研究

Impact of Different Irrigation Methods on Resistance of Rice Against Bending and Breaking

采取小区试验,分析了深水淹灌(FI)、浅水勤灌(FSI)、控制灌溉(CI)和蓄水-控灌(RC-CI)4种灌溉模式下水稻抗倒伏性能的差异。结果表明,节水灌溉模式(CI和RC-CI)下茎粗、茎壁厚、茎秆截面面积、第一和第二节间充实度较传统淹灌(FI和FSI)均显著增加(P<0.05),第一节间长度和第二节间长度显著降低(P<0.05),使得CI和RC-CI处理抗折力较FI处理分别提高32.58%和43.69%,弯曲力矩分别增加8.04%和9.64%,倒伏指数分别降低18.60%和23.60%,且差异显著(P<0.05);CI和RC-CI处理较FSI处理抗折力分别提高13.48%和22.99%,弯曲力矩分别增加0.42%和1.91%,倒伏指数分别降低14.54%和17.08%,且差异显著(P<0.05);节水灌溉模式下水稻植株各器官干物质积累和根冠比较传统淹灌均有所增加,CI和RC-CI处理茎鞘干质量占地上部分干质量比例较FI处理分别增加8.16%和9.00%,穗干质量占地上部分干质量比例分别减少4.03%和4.27%,达到显著性水平(P<0.05),CI和RC-CI处理茎鞘干质量占地上部分干质量比例较FSI处理分别增加2.56%和3.32%,穗干质量占地上部分干质量比例分别减少2.29%和2.53%;根冠比、茎鞘干质量占地上部分干质量比例与倒伏指数极显著负相关(P<0.01);穗干质量占地上部分干质量比例与倒伏指数显著正相关(P<0.05);蓄水-控灌较控制灌溉水稻植株抗折力和弯曲力矩均有所增加,倒伏指数无显著差异(P>0.05)。

The impact of four irrigation methods - deep flooding irrigation （FI）, frequent-shallow irrigation （DSI）, controlled irrigation （CI） and rain-capture and controlled irrigation （RC-CI） -on resistance of rice against bending and breaking was investigated experimentally in this paper. The results showed that in comparison with the tradi- tional flooding irrigation （CK）, the two water-saving irrigation methods （CI and RC-CI） ①significantly increased （P〈0.05）the diameter, wall thickness and cross section of the rice stem, ②increased the plumpness and de- creased the length of the first and second intermodal stems. Compared with FI, CI and RC-CI increased the break- ing-resistance （BR） by 32.58% and 43.69% respectively, and the bending moment （BM） by 8.04% and 9.64% re- spectively, leading to an increase in lodging index LI （LI= BM/BR） by 18.60% and 23.60% respectively. Com- pared with FSI, BR under CI and RC-CI increased by13.48% and 22.99% respectively, whereas their associated BM increased only by 0.42% and 1.91% respectively, leading to a decease in LI by 14.54% and 17.08% respec- tively. The two water-saving irrigation methods increased the accumulation of dry matter androot-shoot ratio in comparison with CK. Compared with FI, CI and RC-CI increased the ratio of stem-sheath dry matter to above- ground dry matter by 8.16% and 9.00% respectively, whereas decreased the ratio of panicle dry matter to above- ground dry matter by 4.03% and 4.27% respectively. Compared with FSI, CI and RC-CI increased the ratio of stem-sheath dry matter to above-ground dry matter by 2.56% and 3.32%, while decreased the ratio of panicle dry matter to above-ground dry matter by 2.29% and 2.53%, respectively. The root - shoot ratio and the ratio of stem- sheath dry matter to above-ground dry materswere negatively correlated with LI （P（0.01）, while the ratio of pan- icle dry matter to above-ground dry matter was positively correlated with LI （P〈0.05）. BR and BM under RC-CI increased slightly in comparison with those under CI, and there was no significant difference in LI between the two irrigation methods （P〉0.05）.