Screening of Groundnut (Arachis hypogaea L.) Genotypes for Heat Tolerance

Groundnut (Arachis hypogaea L.), a self-pollinated legume is an important source of oil and protein. Abiotic and biotic stresses interludes in groundnut production environments. High temperature stress is one of the least well understood and is one of the major uncontrollable factors affecting plant growth, development and productivity. Recognizing the constraints imposed by high temperature to crop adaptation and productivity the present study was planned to screen groundnut genotypes tolerant to heat stress. The experiment was laid out in Alpha-lattice design in two replications. 63 genotypes were evaluated under four different environments viz., E1 (25th Jan?13), E2 (6th Feb?13), E3 (18th Feb?13) and E4 (2nd Mar?13) for the conduct of the experiment. Significant differences for genotypes were found for all the traits under study. Higher magnitude of genotypic and phenotypic coefficient of variation was reported for pod yield, kernel yield, oil yield and haulm weight. High heritability along with high genetic advance as percent of mean was was exhibited by pod yield, kernel yield, hundred kernel weight oil yield, haulm weight, harvest index, pod growth rate, crop growth rate and partioning factor across the four environments. Pod yield was positively and significantly associated with days to maturity, kernel yield, oil yield, oil content, hundred kernel weight, harvest index, haulm weight, crop growth rate, pod growth rate and partitioning factor. Genotype x environment interactions were significant for six traits among which days to 75% flowering, days to maturity and sound mature kernel percentage were highly influenced by heat stress. Based on the mean pod yield for each environment, seven genotypes were identified as top yielders. ICGV 06420 was most stable across the stressed and non-stressed environments. STI was considered more reliable parameter for screening of heat tolerant groundnut genotypes under both stress and non-stress environment. Six genotypes (ICGV 07246, ICGV 07012, ICGV 06039, ICGV 06040, ICGV 03042 and ICGV 06424) were identified as heat tolerant based on STI

A Ashna, 'Screening of Groundnut (Arachis hypogaea L.) Genotypes for Heat Tolerance', 2015