关键词: 轮作, 后效应, 作物产量, 机理

Abstract: After a 6-year (1987-1993) long-term experiment with barley-rice-rice (BRR, CK) and barley-corn-rice(BCR) cropping system, the effect of different cropping system on the yield and growth of the succeeding crops and its mechanism were studied in 1993-1994 in Zhejiang Province. The results showed that the yields of the succeeding crops late-rice andbarley after barley-corn-rice cropping system were significantly higher than that after barley-rice-rice cropping system. There was no significant difference in the yield of the 3rd succeeding crop early rice between two cropping system. It was more beneficial to the increasing of the crop yield and the improving of the soil fertility that two cropping system was rotated each otherevery year in production. The reason for those were mainly that the soil physical and chemical characteristics were more im. proved under BCR than under BRR, so that the hydrolytic N, available P, and available K content of paddy soil under BCRwere higher than those under BRR, the root oxidative power of the succeeding crop late rice was increased under BCR. All ofthose accelerate the growth of the succeeding crops and the absorption of nutrients. Then the effective panicle number, seedsetting rate and filled grain number of the succeeding crop late rice were increased and the effective panicle number and 1000 grain weight of the succeeding crop barley were increased. The result also showed that the fertilizer application could reducethe residual effect of the paddy-upland yearly rotation.

Key words: crop rotation, residual effect, crop yield