耕作方式和生物炭对东北半干旱黑土区大豆根系生长发育的影响OA

In order to clarify the regulatory effects of tillage practices and biochar application on soybean root growth in the semi-arid black soil region of Northeast China,a field positioning experiment was conducted in the semi-arid black soil area of the Songnen Plain.Three tillage practices,namely stubble tillage(S),rotary tillage(R),and stubble tillage plus rotary tillage(SR),together with four biochar application rates(0,1,2,and 3 t·ha-1),were established to systematically monitor and analyze root morphological traits and dry matter accumulation throughout the whole growth period of soybean.The results showed that,tillage practices significantly affected soybean root growth,and root length,root surface area,and root volume at different growth stages generally followed the order of stubble tillage(S)＞stubble tillage plus rotary tillage(SR)＞rotary tillage(R).Biochar application significantly promoted soybean root development,and the promoting effect increased with increasing application rate.At the grain-filling stage,application of 3 t·ha-1 biochar significantly increased root length,root surface area,average root diameter,root volume and root drymater by 51.9％,53.6％,7.4％,79.1％and49.8％,while under stubble tillage,the same biochar rate also increased root dry matter by 14.89％-49.79％compared with the control.Two-way ANOVA showed a significant interaction between biochar application rate and tillage practice for root length(P≤0.05).Overall,the combination of stubble tillage and 3 t·ha-1 biochar was the optimal treatment for promoting soybean root spatial expansion and dry matter accumulation under the conditions of this study.