花铃期不同滴灌水平对海岛棉产量形成的影响

选用新海24号和新海36号为试验材料,研究花铃期3 900、3 150、2 400 m3·hm-2等不同滴灌水平对海岛棉产量形成的影响。结果表明:叶面积指数(LAI)、净光合速率(Pn)、叶绿素SPAD值、干物质积累表现为3900 m3·hm-2处理较高,3 150 m3·hm-2次之,2 400 m3·hm-2较低;棉铃脱落率呈相反趋势,即2 400 m3·hm-2滴灌处理3 150 m3·hm-2滴灌处理3 900 m3·hm-2滴灌处理;滴灌水平3 900 m3·hm-2处理的皮棉产量为2228.49 kg·hm-2,比3 150、2 400 m3·hm-2处理分别高36.68%、49.38%。品种对各滴灌水平响应不同,不同滴灌处理下的LAI、干物质积累和棉铃脱落率为新海24号新海36号,而新海24号的Pn、SPAD值、皮棉产量高于新海36号。因此,花铃期滴灌水平3 900 m3·hm-2条件下有利于实现海岛棉高产。

Effects of drip levels on yield of island cotton at flowering and boll forming stages

This research employed Xinhai24 and Xinhai36 as the materials to study the effects on yield of island cotton at flowering and boll forming stages under different drip levels. The results showed that the LAI, leaf Pn, SPAD value, and dry matter accumulation were highest with drip level of 3 900 m³·hm^-2, followed by that of 3 150 m³·hm^-2, and then that of 2 400 m³·hm^-2. However, cotton boll shedding rate assumed the opposite trend. Lint yield with drip level of 3 900 m³·hm^-2 was 2 228.49 kg·hm^-2, 36.68% and 49.38% higher than those of 3 150 m³·hm^-2 and 2 400 m³·hm^-2, respectively. In addition, the responses to different drip levels varied from varieties. For LAI, dry matter accumulation and cotton boll shedding rate of Xinhai24 were smaller than those of Xinhai36, but leaf Pn, SPAD value, and lint yield were higher than those of Xinhai36. Therefore, combined with the corresponding irrigation system, and also based on the difference in responses from varieties to different drip levels, a drip level at 3 900 m³·hm^-2 would be beneficial to achieve high yield.