不同施氮方式对宽窄行交替休闲种植玉米产量和光合特性的影响

Effect of different nitrogen supply methods on yield and photosynthesis of maize under the alternative fallow high stubble about narrow row and wide row

通过田间试验,研究了玉米宽窄行交替休闲种植模式在5种施氮方式(无肥WN1、一次性施肥WN2、底肥+拔节期追肥WN3、底肥+拔节期追肥+穗肥WN4、缓释肥WN5)下(以常规均匀垄处理CK1、CK2、CK3、CK4、CK5为对照),对玉米产量、冠层透光率、光合速率、叶面积指数等指标的影响。结果表明:宽窄行处理增加后期施肥比例(WN4、WN5)有利于产量的提高,WN4(11 709.33kg/hm2)最高,显著高于除CK3、CK2以外的其他处理,高7.05%～30.29%。在开花期和灌浆期,WN4和CK5光合速率较高,为29.65～34.16μmol/(m2.s),大体上,宽窄行增加后期施肥比例可以增加气孔导度和蒸腾速率,降低胞间CO2浓度。宽窄行各施肥处理底部透光率比均匀垄处理高3.60%～10.64%,WN4透光率低于同种耕作方式其他处理,宽窄行处理叶面积指数除WN4和WN5外均低于对应的常规均匀垄处理。在玉米宽窄行交替休闲种植模式下增加后期施肥(WN4)有利于改善光合作用,延长叶面积持续期,减少漏光损失从而提高玉米籽粒产量。

A field experiment was designed to investigate the effects of five N supply methods （no fertilizer, one fertilizer application, basic＋jointing fertilizer, basic＋jointing＋ earing fertilizer, slow release fertilizer） on grain yield, photosynthesis, leaf area index （LAI） and photosynthetic active radiation （PAR） of maize （Zea mays） under the alternative fallow high stubble about narrow rows and wide rows. In terms of tillage and fertilizer interaction, the yield of basic ＋jointing ＋ earing fertilizer of narrow row and wide row treatment （11 709.3 kg/ha） was higher than that of other treatments by 7.05%--30.29% except for one fertilizer and basic＋jointing fertilizer of conventional treatment. At flowering to filling stage, the best treatments were basic ＋jointing＋earing fertilize and slow release fertilizer of narrow row and wide row treatment （29.65--34. 16 μmol/m2 % s）. Generally, stomatal conductance, transpiration rate of several fertilizer applications were higher than a single fertilizer application in a narrow row and wide row treatment, but intercellular CO2 concentration was the opposite. The mean transmittance of narrow row and wide row treatment was higher than that of conventional treatment by 3.60%--10. 64% and the basic＋jointing＋earing fertilizer was the lowest in narrow row and wide row treatments. The LAI of narrow row and wide row treatment was lower than conventional treatment except for the basic＋jointing＋earing fertilize and slow release fertilizer. The results of this study suggest that basic＋jointing＋earing fertilizer of the narrow row and wide row may be the best management strategy because of its relatively higher grain yield, and improved photosynthesis and transmittance.