title: Optimum Leaf Removal Increases Nitrogen Accumulation in Kernels of Maize Grown at High Density.
abstract: Increasing plant density is one of the main approaches of achieving higher yields for modern maize crop. However, there exists leaf redundancy for high-density maize, and leaves of the upper canopy shade more competent leaves at the middle strata. In a two-year field experiments, Jinhai5, a semi-compact corn cultivar, was grown at a density of 105,000 plants ha-1grown until 3 days after silking (3DAS), when plants were subjected to removal of the uppermost two leaves (S2), four leaves (S4) or six leaves (S6), with no leaf removal as control (S0). We evaluated the effects of leaf removal on N remobilization, photosynthetic capacity of the remaining leaves for N uptake, and N accumulation in kernels. Our present results concluded that, under high plant density, excising the uppermost two leaves promoted N remobilization from vegetative organs to kernels and enhanced photosynthetic capacity for N uptake, leading to an increased N accumulation in kernels (19.6% higher than control). However, four or six uppermost leaves removal reduced N remobilization from stem and photosynthesis for poor N uptake, resulting in 37.5 and 50.2% significantly reduced N accumulation in kernels, respectively.
authors.affiliation: Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess Plateau, Ministry of Agriculture/College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China.|The Chinese Institute of Water-saving Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Tiening
authors.initials: T
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Crop Biology, Agronomy College, Shandong Agricultural University, Tai'an, Shandong Province, 271018, China.
authors.forename: Rundong
authors.initials: R
authors.lastname: Huang
authors.affiliation: Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess Plateau, Ministry of Agriculture/College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China.|The Chinese Institute of Water-saving Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Tie
authors.initials: T
authors.lastname: Cai
authors.affiliation: Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess Plateau, Ministry of Agriculture/College of Agronomy, Northwest A&F University, Yangling, Shaanxi 712100, China.|The Chinese Institute of Water-saving Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Qingfang
authors.initials: Q
authors.lastname: Han
authors.affiliation: State Key Laboratory of Crop Biology, Agronomy College, Shandong Agricultural University, Tai'an, Shandong Province, 271018, China.
authors.forename: Shuting
authors.initials: S
authors.lastname: Dong
mesh_terms: D009584:Nitrogen / Q000378:metabolism*; D010788:Photosynthesis; D018515:Plant Leaves / Q000378:metabolism*; D018547:Plant Stems / Q000378:metabolism; D003313:Zea mays / Q000254:growth & development / Q000378:metabolism*
chemical_list: D009584:Nitrogen