穗分化期UV-B增强辐射对大田玉米农艺性状的影响

以玉米品种农大108为材料,在玉米穗分化期各个阶段田间进行UV-B增强辐射处理,辐射强度比环境强度增强20%,研究了UV-B增强辐射对玉米主要农艺性状的影响。结果表明,拔节开始第1和第2周UV-B增强辐射处理使玉米株高显著降低,分别降低8.91%和7.71%;拔节开始第1和第2周UV-B增强辐射处理显著缩短穗下节间和降低穗位,第2周处理效应最强;第3和第4周处理对株高、穗位、穗下节间长度影响均不显著。整个穗分化期UV-B增强辐射处理对玉米株型和产量性状影响程度最大,株高降低21.30%,穗下各个节间长度降低,穗位下降15.70%,但对穗位比和根层数影响不显著;同时使玉米穗粒数降低18.60%,穗秃尖长度增加89.31%,籽粒产量下降23.40%。拔节开始后第3和第4周UV-B增强辐射处理对玉米果穗性状和产量的影响比拔节前期处理大。

Effects of Enhanced Ultraviolet-B Radiation on the Agronomic Characteristics of Maize in Jointing Stage under Field Condition

Effects of ultraviolet-B(UV-B) radiation on the plant growth and spike of maize in jointing stage were studied using Zea mays L.var.Nongda 108.Results showed that the plant height,spike height and stem length under spike reduced,the grain number per spike and yield dropped and the length of abort cob increased in the exposure of enhanced UV-B radiation with the dose 20% higher than that of environment,the plant height and the spike height dropped 21.30% and 15.70% respectively while the grain number per spike and yield dropped 18.60%and 23.40% and the length of abort cob increased 89.31%.However there were no significant change in the ratio of plant height and spike height,root numbers.Time and dose of UV-B radiation in jointing stage affected the maize differently.Among the treatments,the early half of UV-B radiation during jointing stage impacted plant growth more significantly,while the later impacted spike trait more.