两种气候年型下不同栽培模式对冬小麦根系时空分布及产量的影响

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

【目的】探讨不同栽培模式对冬小麦根系时空分布及产量的影响。【方法】在大田定位试验条件下,设置农民习惯栽培(T1)、相对于农民习惯栽培的节本增产增效栽培(T2)、超高产栽培(T3)和相对于超高产栽培的节本保产增效栽培(T4)等4种栽培模式,比较分析两种气候年型条件下不同栽培模式对冬小麦根系总干重(TDRW)、总根长(TRL)以及不同土层中根干重密度(DRWD)、根长密度(RLD)的时空分布及产量的影响。【结果】冬小麦根系生长受栽培模式调控效应较大,在两种气候年型条件下冬小麦生育中后期不同栽培模式根系时空分布基本一致,即1 m土层的TDRW、TRL均随生育期的推进呈现先升后降的变化特征,T1的根系生长高峰期出现较早,TDRW、TRL均于抽穗期达最大值,T2、T3、T4可延缓根系过早衰减,生长高峰推迟至开花期;不同土层中DRWD、RLD的分布表现不同,T1和T3的根系主要集中在上、中土层,下层土壤中分布相对较少,T2和T4有利于促进小麦整个生育期内深层土壤的根系分布,DRWD和RLD均明显增加。4种栽培模式相比,两种年型下T2、T3、T4的穗粒数和千粒重均较T1显著增加,年型产量差较小,对产量的调控效应强,而T1的年型产量差较大(570.3 kg.hm-2),说明其在应对异常气候对产量的缓解效应相对较差。【结论】综合考虑本试验研究结果和豫北高产灌区生态条件,小麦播量控制在120—150 kg.hm-2,每hm2施纯N180—240 kg、P2O575—90 kg、K2O 60—90 kg、有机肥3 000 kg,合理水肥运筹,结合机械深耕、宽窄行播种以及推迟追肥时期等多项调控措施优化集成的T2、T4两种栽培模式,能有效缓解异常气候对小麦生长发育和产量的负面影响,实现高产稳产、节本高效的目标。

【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.