Root Morphology, Anatomy, and Mycorrhiza of Peristylus goodyeroides (D.Don) Lindl. (Orchidaceae) in Different Life Stages: Ecological Significance and Implication for Conservation

Abstract

Orchid roots have vital functions for water absorption, nutrient uptake, a place of symbiosis with mycorrhizal fungi, adaptation, and survival. The aim of the present study was to investigate root traits in terms of root morphological, anatomical, and mycorrhizal features of a terrestrial orchid, Peristylus goodyeroides in relation to an ecological significance of root traits in survival of seedlings, juveniles, and adults of the orchid. Results showed that some morphological characters (root length and depth), anatomical features (cortical cell size, xylem number and diameter), and mycorrhizal features (peloton size and number) were significantly different between seedlings, juveniles, and adults. In relation to root functional traits, lowest root length, depth, xylem number and diameter, peloton size and number in seedlings can be associated with low capacity in water and nutrient acquisition that might explain low survival of seedlings relative to juveniles and adults. Present study has implication for orchid conservation suggesting high attention in low survival rate of seedlings related to specificity in some of their morphological, anatomical, and mycorrhizal features which can be associated with low capacity in water and nutrient acquisition. It is vital to ensure water availability for seedlings, particularly, during dry seasons to decrease high mortality of seedlings as such high mortality can have adverse impacts on long-term survival of the orchid population.