title: [Effects of nitrogen application rate and post-anthesis soil moisture content on the flag leaf senescence and kernel weight of wheat].
abstract: A rain-proof pool culture experiment was conducted to study the effects of nitrogen (N) application rate and post-anthesis soil moisture content on the flag leaf senescence and kernel weight of wheat. The results indicated that in all N fertilization treatments, the flag leaf SPAD value, soluble protein content, SOD and CAT activities, and photosynthetic rate decreased in the order of 60% -70% > 80%-90% >40%-50% post-anthesis soil moisture content, while the MDA content decreased in reverse order, suggesting that over high or low post-anthesis soil moisture content could cause the early senescence of flag leaves, impact grain filling, and decrease kernel weight. Under the same post-anthesis soil moisture content, the SPAD value, soluble protein content, SOD and CAT activity, and photosynthetic rate increased, while the MDA content decreased with increasing N application rate, indicating that increased N fertilization could postpone the senescence of wheat flag leaves. However, over N application was not favorable to the increase of kernel weight, especially under the condition of post-anthesis soil moisture deficiency. It was concluded that appropriate N application and post-anthesis soil moisture content control could postpone the plant senescence and increase the kernel weight of wheat.
authors.affiliation: College of Agriculture and Plant Protection, Qingdao Agricultural University, Qingdao 266109, Shandong, China. zhaochangxing@126.com
authors.forename: Chang-xing
authors.initials: CX
authors.lastname: Zhao
authors.forename: Dong-hui
authors.initials: DH
authors.lastname: Ma
authors.forename: Yue-fu
authors.initials: YF
authors.lastname: Wang
authors.forename: Qi
authors.initials: Q
authors.lastname: Lin
mesh_terms: D018533:Biomass; D005308:Fertilizers; D009584:Nitrogen / Q000032:analysis* / Q000378:metabolism; D018515:Plant Leaves / Q000502:physiology; D011506:Proteins / Q000032:analysis; D012987:Soil / Q000032:analysis*; D014908:Triticum / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D014867:Water / Q000032:analysis* / Q000378:metabolism
chemical_list: D005308:Fertilizers; D011506:Proteins; D012987:Soil; D014867:Water; D009584:Nitrogen