玉米根茬还田对下茬玉米生长发育及产量的影响

Effect of Corn Stubble Remaining in Field on Corn Growth and Yield of Next Year

通过２ 年的大田试验，研究了玉米根茬还田在不同气候条件下，对下茬玉米生长发育和产量的影响。结果表明：影响根茬还田效果大小和好坏的主要限制因素是化肥的配合施用情况及玉米生育期间的降水情况。在降水较好的１９９６ 年，玉米根茬还田使下茬玉米茎秆加粗，吐丝期提前３ ～５ ｄ ，果穗长、果穗重、穗粒重提高，百粒重稍有提高。配合施用化肥，尤其是氮肥，对改善玉米果穗性状及产量有利。在玉米生育期严重干旱的１９９７ 年，玉米根茬还田后，果穗性状及产量不如其刨茬对照，这主要是由干旱时根茬腐解速度减慢，发挥不了留茬的效果，且根茬腐解使通气孔隙增多，消耗较多的水分，导致干旱加重。因此，玉米根茬还田在吉林省降雨较多的中东部地区采用更易发挥作用。

This paper studied effect of the corn stubble remaining in field on corn growth and yield under different climate by two years' field experiment. The results showed that the main factors of effects corn stubble were chemical fertilizer applied and precipitation in corn growth period. In 1996 of better precipitation, the corn stubble had effects of widening corn stem, aheading emergence of female flower 3～5 days, improving ear length, ear weight and grain weight, increasing weight of 100 grain a little, and corn stubble co ordinating chemical fertilizer, especially N chemical fertilizer obviously increased ear properties and yield. But, in 1997 of very drought in corn growth period, the ear properties and yield of corn stubble remaining in field were lower than without corn stubble, the reason perhaps was that corn stubble rotten slowly and couldn't exert its effect, and the courge of corn stubble rotten increased aerating hole in soil and weared down valuable water in soil so as to intensify drought. Therefor, corn stubble remaining in field easily exerted its effect, if it was applied in middle and east area of Jilin Province.