Modifications in root and stem anatomy for water conservation in some diverse blue panic (Panicum antidotale Retz.) ecotypes under drought stress.

摘要

Five ecotypes of Panicum antidotale Retz. adapted to diverse habitats were subjected to drought stress to evaluate their drought tolerance in relation to adaptive anatomical structures. The ecotype from non-stressed habitat had intensive sclerification as well as crystallization in parenchymatous cells, which help prevent water loss. The ecotype from drought-prone habitat had well-developed metaxylem vessel area for better conduction of water and nutrients, and pith area for better storage of water. The ecotype collected from salinity-affected habitat as well as that from saline and waterlogged habitat showed extensive sclerification in the vascular region, which is vital for preventing water loss. The ecotype from a salinity- and drought-prone habitat showed increased metaxylem vessel number and formation of additional metaxylem vessels in the pith region for better conduction, multi-layer exodermis and intensive sclerification for prevention of water loss, and increased parenchymatous region for better storage of water. The most promising anatomical features found in highly drought tolerant ecotypes were increased metaxylem number, multi-layered exodermis, and intensive sclerification in vascular region.Digital Object Identifier http://dx.doi.org/10.1080/15324982.2012.727947