Effects of Different Cultivation Patterns on the Spatial-Temporal Distribution Characteristics of Roots and Grain Yield of Winter Wheat in Two Climatic Years

【Objective】The objective of this study was to investigate the effects of different cultivation patterns on the spatial-temporal distributions of winter wheat roots,and grain yields.【Method】 Four cultivation patterns including local cultivation pattern usually used by farmers(T1),cost-saving,high-yielding and high efficiency cultivation pattern(T2),super high-yielding cultivation pattern(T3),and cost-saving,stable yield and high efficiency cultivation pattern(T4) were designed in the present study.The effects of these four cultivation patterns on the grain yields and spatial-temporal distribution characteristics of roots(total dry root weights,TDRW;total root lengths,TRL;dry root weight density,DRDW;root length density in different soil layers,RLD;etc) were measured in fixed field experiment.【Result】The results showed that wheat root growth was greatly affected by different cultivation patterns.Dry weights and lengths of total roots in 1 m soil layer firstly increased,then decreased in all of cultivation patterns during the whole growth and development periods.The peak value for the root growth appeared earlier in T1 cultivation pattern than those of other parameters.And TDWR and TRL in T1 cultivation pattern reached the maximum at the heading stage.T2,T3 and T4 cultivation patterns could alleviate the growth rates of roots and the maximum rates of root growth in these cultivation patterns were delayed to the anthesis.The distributions of roots in both T1 and T3 cultivation patterns appeared mainly at the above layers of soil,but rarely at the lower layers.Both T2 and T4 cultivation patterns helped to improve the growth of roots at the deep layers of soil,and their DRWD and RLD in deep soil layers were significantly more than those of T1 and T3 cultivation patterns.Grains per spike and 1 000-grain-weight in T2,T3 and T4 cultivation patterns were significantly more than those of T1 in the two years of experiment,and differences in yields in these cultivation patterns were no significant between the two years of experiment.However,difference in yield of T1 cultivation pattern(570.3 kg·hm-2) was significant between the two years of experiment.This indicated that T1 cultivation pattern had lower capacity to resist the adverse environments.【Conclusion】 With the comprehensive considerations for both the data in the present study and ecological conditions in the north of Henan province,both T2 and T4 cultivation patterns effectively decreased the adverse effects of abiotic environments on development and yields,achieved higher and stable yields,cost saving and high efficiency.The reasons are that T2 and T4 cultivation patterns were designed according to many efficient methods,such as reducing fertilizer inputs(applied N180-240 kg,P2O575-90 kg,K2O 60-90 kg,organic manure 3 000 kg per hectare),deep ploughing,and wide-narrow rowing,decaying fertilization,etc.