Year: 2014
Type: article
Abstract: The objective of this research was to investigate the relationship between rice roots negative phototropism and endogenous plant hormone levels, as well as the impact of exogenous hormones on rice root growth.The adventitious roots and primary roots of conventional cultivars Yangdao 6 (indica), Nipponbare (japonica), Zhonghua 11 (japonica) and its OsPIN1a over expressed transgenic seedlings were used to observe the process of root negative phototropism, measure contents of endogenous auxin (IAA), gibberellin (GA 3 ) and abscisic acid (ABA) in the bending part of root tips, and investigate the impact of exogenous hormones to rice root morphology and anatomy.Results indicated that seedling roots of both Yangdao 6 and Nipponbare had negative phototropism, and the lateral roots and adventitious roots of Yangdao 6 showed stronger negative phototropism.Plant hormones and negative phototropism of rice root and root development are closely linked.Under unilateral illumination, endogenous IAA, GA 3 and ABA levels declined.The content of these phytohormones in the irradiated side was lower than that in the shaded side.The treatment of unilateral light and exogenous IAA induced a large number of root hairs in Yangdao 6.Compared with conventional rice, the angle of negative phototropism was lager in OsPIN1a transgenic plant.There was no direct relationship between exogenous GA 3 and ABA treatments and root negative phototropism of rice.Exogenous ABA inhibited root growth obviously.The total absorption surface area, root number and root length per plant were significantly reduced by ABA treatment.The treatment of 10 μmol L -1 ABA not only caused a dysplasia of both meristematic and elongation zone but also promoted the development of the central vascular tissue in root tips.
Source: ACTA AGRONOMICA SINICA
Institution: Yangzhou University
Language: English
Topic: Light effects on plants
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W2559895266