Differential response of root morphology to potassium deficient stress among rice genotypes varying in potassium efficiency

• Published in: Journal of Zhejiang University. B. Science Vol. 9; no. 5; pp. 427 - 434
• Main Authors: Jia, Yan-bo, Yang, Xiao-e, Feng, Ying, Jilani, Ghulam
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Zhejiang University Press 01.05.2008; Springer Nature B.V; MOE Key Laboratory of Polluted Environments Remediation and Ecosystem Health, Zhejiang University, Hangzhou 310029, China; Institute Calibration and Testing for Quality and Technical Supervision, Hangzhou Bureau of Quality and Technical Supervision, Hangzh%MOE Key Laboratory of Polluted Environments Remediation and Ecosystem Health, Zhejiang University, Hangzhou 310029, China%MOE Key Laboratory of Polluted Environments Remediation and Ecosystem Health, Zhejiang University, Hangzhou 310029, China; Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition, Zhejiang University, Hangzhou 310029, China%Department of Soil Sciences, Arid Agriculture University, Rawalpindi 46300, Pakistan; Zhejiang University Press
• Subjects: Biomedical and Life Sciences; Biomedicine; Environmental Sciences; Genotype; Oryza - growth & development; Oryza - metabolism; Oryza - ultrastructure; Plant Roots - growth & development; Plant Roots - ultrastructure; Potassium - metabolism; 基因突变; 根表面积; 遗传差异; Fine root development; Root surface area; Genotypic difference; Root cell ultra-structure; X5; Potassium (K) efficiency; Root cell utra-structure
• ISSN: 1673-1581; 1862-1783
• DOI: 10.1631/jzus.b0710636

Disparity in the root morphology of six rice （Oryza sativa L.） genotypes varying in potassium （K） efficiency was studied with three K levels： 5 mg/L （low）, 10 mg/L （moderate） and 40 mg/L （adequate） in hydroponic culture. Morphological parameters included root length, surface area, volume and count of lateral roots, as well as fine （diameter〈0.2 mm） and thick （diameter〉0.2 mm） roots. The results indicate that the root growth of all genotypes was reduced under low K, but moderate K deficiency increased the root length of the efficient genotypes. At deficient and moderate K levels, all the efficient rice genotypes developed more fine roots （diameter〈0.2 mm） than the inefficient ones. Both fine root count and root surface area were found to be the best parameters to portray K stress in rice. In accordance with the root morphology, higher K concentrations were noted in shoots of the efficient genotypes when grown at moderate and deficient K levels, indicating that root morphology parameters are involved in root uptake for K and in the translocation of K up to shoots. K deficiency affected not only the root morphology, but also the root ultra-structure. The roots of high-efficient genotypes had stronger tolerance to K deficient stress for root membrane damage, and could maintain the developed root architecture to adapt to the low K growth medium.