Quantitative analysis of maize leaf collar appearance rates

Honggen Xu; Bo Ming; Keru Wang; Jun Xue; Peng Hou; Shaokun Li; Ruizhi Xie

doi:10.1016/j.plaphy.2023.01.016

Quantitative analysis of maize leaf collar appearance rates

Plant Physiol Biochem. 2023 Mar:196:454-462. doi: 10.1016/j.plaphy.2023.01.016. Epub 2023 Jan 11.

Authors

Honggen Xu¹, Bo Ming¹, Keru Wang¹, Jun Xue¹, Peng Hou¹, Shaokun Li², Ruizhi Xie³

Affiliations

¹ Key Laboratory of Crop Physiology and Ecology, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China.
² Key Laboratory of Crop Physiology and Ecology, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China. Electronic address: lishaokun@caas.cn.
³ Key Laboratory of Crop Physiology and Ecology, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China. Electronic address: xieruizhi@caas.cn.

PMID: 36758292
DOI: 10.1016/j.plaphy.2023.01.016

Abstract

Phyllochron, the reciprocal of the leaf appearance rate, is a critical genetic parameter in crop models for predicting growth characteristics and yield. Previous studies have shown that existing observations and predictive algorithms do not adequately represent a broad range of cultivars and environments. Here, we conducted a series of experiments in the field to quantify and disentangle the effects of sowing date and cultivar on maize leaf collar appearance (LCA). A bilinear model was found to accurately fit maize LCA (R²_adj > 0.99); this model revealed a slower rate of LCA for the first leaves compared to the last leaves. Turning points in the model occurred between the 9.2th and the 13.1th leaf, nearly always below the ear leaf and around a leaf age index (LAI) of 60.0%. The phyllochron before the turning point (PHYLL Ⅰ) was significantly higher than the phyllochron after the turning point (PHYLL Ⅱ) for all three maize cultivars, and PHYLL Ⅰ was approximately two times higher than PHYLL Ⅱ on average. Both PHYLL Ⅰ and PHYLL Ⅱ were significantly affected by sowing date and cultivar. Variations in PHYLL Ⅰ and PHYLL Ⅱ indicated strong plasticity in maize phyllochron at different leaf ranks. The results of this study are critical for improvement of maize management practices and extend the applicability of phyllochron-collar measurements in crop models.

Keywords: Bilinear model; Genetic parameters; Maize; Phenology; Phyllochron; Sowing date.

MeSH terms

Algorithms
Plant Leaves*
Zea mays* / genetics