Bowen Luo1,2,3· Haiying Zhang2,3· Zheng Han2,3· Xiao Zhang2,3· Jianyong Guo2,3· Shuhao Zhang2,3· Xianfu Luo2,3· Jin Zhao2,3· Wei Wang2,3· Guohui Yang2,3· Chong Zhang2,3· Jing Li2,3· Junchi Ma2,3· Hao Zheng4· Zirui Tang4· Yuzhou Lan5· Peng Ma6,7· Zhi Nie8· Yunjian Li2,3· Dan Liu2,3· Ling Wu2,3· Duojiang Gao2,3· Shiqiang Gao2,3· Shunzong Su9· Jia Guo10· Shibin Gao1,2,3
Received: 13 March 2024 / Accepted: 1 June 2024 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024
Abstract
Examining the connection between P and starch-related signals can help elucidate the balance between nutrients and yield. This study utilized 307 diverse maize inbred lines to conduct multi-year and multi-plot trials, aiming to explore the relationship among P content, starch content, and 100-kernel weight (HKW) of mature grains. A signifcant negative correlation was found between P content and both starch content and HKW, while starch content showed a positive correlation with HKW. The starch granules in grains with high-P and low-starch content (HPLS) were signifcantly smaller compared to grains with low-P high-starch content (LPHS). Additionally, mian04185-4 (HPLS) exhibited irregular and loosely packed starch granules. A signifcant decrease inZmPHOsgenes expression was detected in the HPLS line ZNC442 as compared to the LPHS line SCML0849, while no expression diference was observed in AGPase encoding genes between these two lines. The down-regulated genes in ZNC442 grains were enriched in nucleotide sugar and fatty acid anabolic pathways, while up-regulated genes were enriched in the ABC transporters pathway. An accelerated breakdown of fat as the P content increased was also observed. This implied that HPLS was resulted from elevated lipid decomposition and inadequate carbon sources. The GWAS analysis identifed 514 signifcantly associated genes, out of which 248 were diferentially expressed. Zm00001d052392 was found to be signifcantly associated with P content/HKW, exhibiting high expression in SCML0849 but almost no expression in ZNC442. Overall, these fndings suggested new approaches for achieving a P-yield balance through the manipulation of lipid metabolic pathways in grains.