Leaf area establishment of a maize (Zea mays L.) field crop under potassium deficiency

• Published in: Plant and soil 2004-08, Vol.265 (1-2), p.75-92
• Main Authors: Jordan-Meille, L, Pellerin, S
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; calcium; Cereal crops; Corn; Crop science; Deficiencies. Phytotoxicity of elements. Salinity; Economic plant physiology; field crops; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; grain crops; Growth and development; Leaf area; Leaf area index; leaf development; leaf elongation duration; leaf elongation rate; Leaves; Life Sciences; magnesium; Moisture content; Morphogenesis, differentiation, rhizogenesis, tuberization. Senescence; Nitrogen, phosphorus, potassium fertilizations; nutrient content; Plant growth; Plants; Potassium; Potassium fertilization; senescence; shoots; soil nutrients; soil-plant interactions; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Sowing; Sugars; Vegetal Biology; Water content; Zea mays
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-005-0695-z

The effect of K deficiency on leaf area index (LAI) establishment of a maize field crop (Zea Mays L.) was studied. The experimental work was carried out in 2000 and 2001 on a long-term K fertilization trial. Three K fertilization regimes (K0, K1 and K4) have been applied since 1995, thus leading to contrasted levels of available K in soils (14, 23 and 44 µg exchangeable K per g of dry soil for the three fertilization regimes, respectively). The rate of leaf appearance, the leaf elongation rate (LER), the leaf elongation duration (LED), their final length and width and the number of senescent leaves were investigated. K concentrations in shoot tissue water were lower in K0 plants, whereas concentrations of Ca and Mg were higher. The LAI was reduced in the K0 treatment, mainly because of a slower rate of leaf appearance and a reduced final size of individual leaves. The reduced final length of individual leaves was almost entirely accounted for by a reduced LER during the quasi linear elongation phase. The LED was only slightly affected. A rough parallelism was observed between the relative reduction of leaf length and the relative reduction of plant water content during leaf elongation. Conversely, there was no evidence that leaf elongation was limited by carbohydrate availability in leaf growing zones. This suggests that K deficiency reduced LER probably because of altered plant-water relationships. On the whole, these results strengthen the idea that leaf growth is a key variable for analyzing, and later on modeling, crop growth under K deficiency.