Screening ten genotypes of natural rubber seedlings (<i>Hevea Brasiliensis</i> mull. arg) for drought tolerance in Umudike, south eastern Nigeria

Abstract

A field study was conducted in 2012 and 2013 cropping season at the Research Farm of National Root Crops Research Institute, (NRCRI) Umudike, in Abia State, to screen 10 rubber genotypes collected from Rubber  Research Institute of Nigeria for tolerant to drought conditions. The aim was to select tolerant genotypes for  development of new clones of natural rubber and to study the association (r) between the 9 traits used as  indices for picking drought tolerant genotypes. The experiments were laid out in a Randomized Complete Block Design (RCBD) using three replications. Thirty rubber seedlings per plot were transplanted from pre-nursery to the main nursery at the spacing of 100 x 30 cm on a well prepared bed. Results obtained in the field over the two years indicated that variations existed in the level of drought tolerance among the genotypes. For agronomic traits, all the traits showed significant differences (P<0.05) among the genotypes. GT1, RRIM 600, PR107 and Nig 804 showed more tolerance to drought conditions from 0 to 40days than the other genotypes and PB5/51, RRIM 628 and Nig 800 were found to be more susceptible to drought when compared with the other genotypes in the field. Life saving irrigation may become an essential farm practice for the survival of these genotypes in the nursery field during the dry seasons or periods of drought