Transcriptional analyses of maize leaves in response to high‐density planting. (21st February 2022)

• Record Type: Journal Article
• Authors: Zhao, Chenghao; Ji, Shuwen; Ge, Chao; Su, Yujing; Shi, Zhongxian; Cui, Zhenhai; Zhang, Ao; Wang, Zuoying; Ruan, Yanye; Zhang, Lijun; Ma, Xinglin
• Is Part Of: Agronomy Journal. Volume 114:Number 2(2022)
• Page Start: 1385
• Page End: 1400
• Publication Date: 2022-02-21
• Subjects: Agronomy -- Periodicals; 630
• DOI: 10.1002/agj2.20825
• Languages: English
• ISSNs: 0002-1962

Abstract

Abstract: Maize ( Zea mays L.) is one of the major cereal crops worldwide. Increasing planting density is an effective way to improve crop yield. However, plants grown under high‐density conditions compete for water, nutrients, and light, which often leads to changes in productivity. To date, few studies have determined the transcriptomic differences in maize leaves in response to different planting densities. This study examined the whole‐genome expression patterns in the leaves of maize planted under high and low densities to identify density‐regulated genes. Leaves at upper, ear, and lower stem nodes were collected at the grain‐filling stage of the maize hybrid Xianyu335 grown under low‐density planting and high‐density planting. In total, 72, 733, and 1, 739 differentially expressed genes (DEGs) were identified in the respective upper, ear, and lower leaves under HDP. Upregulated and downregulated DEGs in the upper and lower leaves were similar in number, whereas upregulated DEGs in the ear leaves were significantly higher in number than the downregulated DEGs. Functional analysis indicated that genes responding to HDP‐related stresses were mediated by pathways involving four phytohormones responsible for metabolism and signaling, osmoprotectant biosynthesis, transcription factors, and fatty acid biosynthesis and protein kinases, which suggested that these pathways are affected by the adaptive responses of maize plants grown at high density. Research findings elucidated the molecular mechanisms underlying the physiological and biochemical responses of the leaves of maize planted at high density. Core Ideas: Corn and soybean yield‐limiting factors differed across Mid‐Atlantic locations. High‐residue cultivation decreased weed biomass but had variable effects on yield. Cover crop biomass was not consistently correlated with lower weed biomass. Planting date influenced predatory arthropod activity‐density in corn. Adaptive pest management tactics are needed to balance management tradeoffs.