关中平原夏玉米临界磷浓度稀释曲线构建与磷营养诊断  

Critical phosphorus dilution curve and phosphorus nutrition diagnosis of summer maize in Guanzhong Plain

作　　者：刘苗 刘朋召 师祖姣 王小利[1] 王瑞[1] 李军[1] LIU Miao;LIU Peng-zhao;SHI Zu-jiao;WANG Xiao-li;WANG Rui;LI Jun(College of Agronomy,Northwest A&F University/Key Laboratory of Crop Physiecology and Tillage Science in Northwestern Loess Plateau,Ministry of Agriculture and Rural Affairs,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学农学院/农业农村部西北黄土高原作物生理生态与耕作重点实验室,陕西杨凌712100

出　　处：《植物营养与肥料学报》2021年第9期1548-1559,共12页Journal of Plant Nutrition and Fertilizers

基　　金：国家科技支撑计划项目(2015BAD22B02);国家高技术研究发展计划(863计划)项目(2013AA102902);国家自然科学基金项目(31801300)。

摘　　要：【目的】通过分析不同施磷水平下夏玉米地上部生物量与其植株磷浓度的变化关系,构建临界磷浓度稀释曲线模型,为夏玉米磷素优化管理及磷营养诊断提供理论基础。【方法】2019—2020年在陕西关中平原,以两个玉米品种郑单958和豫玉22为试验材料进行田间定位试验。共设4个施磷量处理(P_(2)O_(5)):0、60、120、180 kg/hm^(2)。在夏玉米拔节期、抽雄期、灌浆期和成熟期进行地上部取样,分析夏玉米地上部干物质量、全磷含量以及产量。利用2019年试验数据构建夏玉米临界磷浓度稀释曲线模型和磷素营养指数,利用2020年数据对模型进行验证。【结果】增施磷肥能显著提高夏玉米产量、地上部生物量和植株磷浓度,两个品种之间没有显著差异。随施磷水平的提高,夏玉米产量表现为先增加后减少,P120处理可获得最高产量,产量效应方程显示两年两个品种夏玉米平均理论最高产量对应的施磷量为110.2 kg/hm^(2)。由产量构成要素看出,施磷对穗数没有显著影响,但能显著提高穗粒数和百粒重,且施磷对玉米穗粒数的影响大于对百粒重的影响。地上部生物量表现为P0<P60<P180<P120处理,但P180与P120处理间差异不显著。玉米植株磷浓度均随施磷水平的提高而增加,并随生育进程的推进和地上部生物量的增加而降低。根据2019年地上部干物质重与其磷浓度变化关系构建夏玉米临界磷浓度(P_(c))变化曲线:P_(c)=8.11DM^(−0.22)(R^(2)=0.886)。模型拟合的植株磷浓度和2020年玉米实际磷浓度线性相关,稀释曲线模型的RMSE和n-RMSE分别为1.146和18.23%,说明模型具有较好的稳定性。基于临界磷浓度稀释曲线计算磷营养指数(PNI),各生育时期PNI值随磷肥用量增加而增大,随生育进程推进呈现先升高后降低趋势。PNI与相对吸磷量(RP_(upt))、相对地上部生物量(RDW)和相对产量(RY)均呈极显著相关。【结论】本研究�【Objectives】This study analyzes the relationship between aboveground biomass and maize phosphorus(P)content under different P application rates to construct a critical P dilution curve for fast diagnosis of maize P nutrition.【Methods】Field experiments were conducted in Guanzhong Plain,Shaanxi Province in 2019 and 2020,using the maize cultivars Zhengdan 958(ZD958)and Yuyu 22(YY22)as test materials.The four treatments of P_(2)O_(5) application rates were 0,60,120,and 180 kg/hm^(2).The aboveground parts of maize plants were sampled at jointing,tasseling,filling,and maturity stages to determine dry matter accumulation,P concentration,and yield.The data obtained in 2019 were used to construct the critical P dilution curve model and the corresponding P nutrition index(PNI).The data obtained in 2020 were used to verify the models'accuracy.【Results】Increased P application rate(P<0.05)increased yield,aboveground biomass,and P concentration of summer maize,but there was no significant difference(P>0.05)between the two varieties.With increasing P application rate,the yield of summer maize increased at first and later decreased,with P120 treatment recording the highest.The yield effect equation showed that the average theoretical maximum yield of the two varieties of summer maize in the years under study corresponds to a P application rate of 110.2 kg/hm^(2).P application had no significant effect(P>0.05)on the number of ears per hectare but increased the kernel number per ear and 100-grain weight.However,the effect of the application on kernel number per ear was greater than that on 100-grain weight.The aboveground biomass was in the order P0<P60<P180<P120,with no significant difference(P>0.05)between P180 and P120 treatments.Maize P concentration increased with increasing P application rate;however,it decreased with the advancement of growth and the accumulation of aboveground dry matter by weight.Based on the aboveground dry matter weight and P concentration of maize plants in 2019,the critical P dilution curv

关 键 词：夏玉米 施磷量 临界磷稀释曲线 磷营养指数 

分 类 号：S513[农业科学—作物学]