Identification of genes and genetic mechanisms contributing to heat tolerance. Sources of heat tolerance

Abstract

Two temperature controlled greenhouses were used to conduct a trial at CIAT. A set of 192 genotypes including 101 accessions of P. vulgaris, 81 accessions of P. acutifolius and 10 accessions of P. parvifolius, were evaluated under heat stress conditions (Minimum temperature 25°C, Maximum temperature 35°C) to quantify phenotypic variation in heat tolerance. Experimental units consisted of 1 row of 1 m long with a row-to-row distance of 0.6 m and plant-to-plant distance of 7 cm. A number of plant traits were evaluated, that included: days to flowering (DF), days to physiological maturity (DPM), SPAD chlorophyll meter readings (SCMR), canopy temperature, photosynthetic efficiency, seed number per area (SNA), pod number per area (PNA), pod harvest index (PHI), and grain production.