小麦锌吸收转移对土施锌肥响应的区域差异OA

[Objective]The zinc(Zn)uptake and translocation in wheat have a significant impact on grain Zn concentration.The aim of this study was to understand the relationships between pre-anthesis and post-anthesis Zn uptake and translocation,grain Zn concentration,and Zn rates across different regions,so as to provide the support to the scientific application of Zn fertilizer and the enhancement of wheat grain Zn biofortification.[Method]Based on the location-fixed field experiment initiated in major wheat-growing regions of China at 2022,including Yongshou of Shaanxi,Baixiang of Hebei,Zitong of Sichuan,and Shucheng of Anhui,soil available Zn concentration,wheat yield,biomass,yield components and Zn concentration in various plant parts were analyzed to understand the regions varies for grain Zn concentration,pre-and post-anthesis Zn uptake,and transportation responses to different Zn application rates during the wheat growing season of 2023-2024.[Result]The grain yield and yield components did not change with Zn application,but grain Zn concentration increased significantly.The biofortified target of 40.0 mg·kg-1 and the highest of 51.7 and 80.7 mg·kg-1 was achieved respectively in Sichuan and Anhui,but Shaanxi and Hebei could not,with the highest of 32.2 and 34.5 mg·kg-1,respectively.For each 1.0 kg Zn·hm-2 input,Zn uptake in pre-anthesis increased by 9.8,7.4,3.0,and 3.0 g·hm-2 at Anhui,Sichuan,Hebei,and Shaanxi,respectively;Zn uptake in post-anthesis increased by 9.8,8.3,and 0.97 g·hm-2 at Sichuan,Anhui,and Hebei,respectively,but no significant increase was found in Shaanxi;Zn translocation in post-anthesis increased by 5.6 and 2.5 g·hm-2 at Anhui and Shaanxi,respectively,and decreased by 1.6 g·hm-2 at Sichuan,but no significant increase was found in Hebei.For the Zn uptake and translocation efficiencies,with each 1.0 kg Zn·hm-2 input,the increase of 0.71,0.53,0.47,and decrease of 0.40 percentage points in pre-anthesis Zn uptake efficiency was observed at Shaanxi,Hebei,Anhui and Sichuan,respectively;the decrease of 0.71,0.53,0.47,and increase of 0.40 percentage points in post-anthesis Zn uptake efficiency was observed at Shaanxi,Hebei,Anhui and Sichuan,respectively;the decrease of 1.41 and 0.44 percentage points in post-anthesis Zn translocation efficiency was observed at Sichuan and Hebei,respectively,but not decrease in Shaanxi and Anhui;the decrease of 0.06 and 0.13 in anthesis Zn transfer index from root to shoot was observed at Sichuan and Anhui,respectively,but not decrease in Shaanxi and Hebei.[Conclusion]Wheat grain Zn biofortification was collectively influenced by Zn uptake and translocation processes.Compared with efficiencies of the pre-anthesis and post-anthesis Zn uptake,Zn uptake contribution,post-anthesis Zn translocation,and translocation contribution,the pre-anthesis and post-anthesis Zn uptake and translocation exhibited greater impacts by regions variations of wheat grain Zn concentration.Zn fertilization increased pre-anthesis and post-anthesis Zn uptake,while its effect on post-anthesis Zn translocation varied with regions.Compared with post-anthesis Zn translocation,the pre-anthesis and post-anthesis Zn uptake,exhibited greater impacts in wheat grain Zn concentration,particularly the post-anthesis Zn uptake.Therefore,enhancing the soil Zn supply capacity in main wheat production regions of China and promoting Zn uptake in wheat,particularly post-anthesis Zn uptake,could effectively increase grain Zn concentration and achieve the wheat Zn biofortification target.