不同覆膜方式对棉花生长的影响

[目的]针对膜下滴灌造成棉田土壤次生盐渍化、棉花根系变浅造成后期早衰和残膜污染等问题,初步探索揭膜栽培棉花的方法,明确头水后揭膜对棉花生长的影响.[方法]滴灌带浅埋的前提下设不铺膜、头水后揭膜和正常铺膜3个处理,研究不同覆膜方式对棉花生长发育的影响.[结果]6月上旬以前覆膜增温效果显著,随着棉田封垄,头水后揭膜影响土壤含水量,但可以提高地温,显著增加侧根数,提高根系的质量.头水后揭膜和覆膜栽培的LAImax(最大叶面积指数)分别为3.93和3.71,成熟时干物质分别为1 161.46和1 063.52 g/m2,产量为5 090.4和4 855.5 kg/hm2.[结论]棉花无膜栽培,造成苗期生长缓慢,整个生育期明显滞后,减产严重.头水后揭膜,可以促进棉花的生长,是可行的棉花栽培方式.

Effects of Different Ways of Film Mulching on Cotton Growth

【Objective】Drip irrigation under film can lead to a series of problems: soil secondary salinization,depth of root shallow,cotton caducity in later stage and residual film pollution.This study made a preliminary research on methods of cotton cultivation by uncovering mulching films,especially the effect on cotton growth when uncovering films after the first irrigation.【Method】An experiment was carried out for studying influences of different ways of film mulching on growth and yield of cotton.Three treatments were designed: no film,uncover film after the first irrigation and normal mulching film,all with shallow drip irrigation tapes.【Result】Results showed that: Mulching film had significant effect on soil temperature before the first ten days of June.Uncovering film after the first irrigation affected content of soil humidity,but it can improve temperature of soil and numbers of lateral root,and promote root quality.For uncovering film after the first irrigation and CK, the highest leaf area reached 3.93 and 3.71 respectively,and dry material were 1 161.46 and 1 063.52 g/m2 when maturated.The yields of two treatments were 5 090.4 and 4 855.5 kg/hm2.【Conclusion】Cultivating cotton without films led to slower development,delayed growth stage and yields reduction.Uncoverying film after the first irrigation can promote cotton growth.It is a feasible method for cotton cultivation.