连作下玉米秸秆腐解液对种子萌发的影响

Effect of Decomposed Liquids of Maize Stalk on Seeds Germination under Successive Cultivation

针对黑龙江省玉米长期连作及玉米秸秆还田的普遍现象,研究了腐解不同时间(0、60、120、180、240、300d)及不同浓度(0.03125、0.0625、0.125、0.25、0.5gDW/mL)的玉米秸秆腐解液对玉米种子萌发的影响。结果表明,玉米秸秆腐解液对玉米种子的萌发表现出"低促高抑"的化感作用,低浓度(0.125gDW/mL以下)的腐解液对玉米种子萌发有促进的作用,高浓度(0.25gDW/mL以上)则抑制作用比较明显;随玉米秸秆腐解时间的延长,腐解液对玉米种子萌发的抑制作用呈逐渐减弱趋势,60d秸秆腐解液各浓度处理下玉米种子,其发芽率、发芽势、发芽指数均显著低于其他处理,幼苗的胚根长度、胚轴长度和鲜重相对于其他处理偏低,180d和240d腐解液各浓度处理下的种子发芽率、发芽势、发芽指数略高于其他时期腐解液同浓度条件下的处理,幼苗的胚根长度、胚轴长度和鲜重也高于其他时期腐解同浓度条件下的处理,且240d的腐解液对种子萌发的促进作用最强。

The study was to explore the effects of maize long-term continuous cropping and straw return on maize seed germination in Heilongjiang. We set four decomposing time（0,60,120,180,240,300d） and five different concentrations （0.03125, O. 0625,0.125,0.25,0.5 gDW/mL） of decomposed liquids. The results indicated that the decomposed liquids from maize stalk had allelopathy on maize seed germination, which showed a promoting effect at low concentration. Decomposed liquids had promoting tendency on seed germination under low concentration （0. 125gDW/mL below）. There was a significant inhibiting effect under high concentration （0.25gDW/mL above）. With the time extension of stalk decomposing, the inhibition of decomposed liquids on maize stalk on maize seeds germination showed gradually weakened tendency. Under 60d decomposed liquid, in all concentration treatments, seeds germination rate, germination potential, and germination index were lower than other treatments, besides,radicle length, hypocotyl length, and fresh weight of seedling were lower than other decomposed liquid relatively. Under 180d and 240d decomposed liquid, seeds germination rate, germination potential and germination index were a little higher than other decomposed liquid. Under the same concentration level treatment, radicle length, hypocotyl length, and fresh weight of seedling were higher basically than other decomposed liquid. Under the same concentration level treatment,240d decomposed liquid showed the strongest promoting effect on seeds germination