Investigation of some parameters affecting the germination of cotton seed in cool conditions

Cotton is grown in temperate conditions. It is important to investigate how cotton genotypes behave under cool conditions during germination. This study aims to determine the factors affecting the germination of cotton seeds under cool temperature conditions and to relate germination percentages to some seed and fiber characteristics of cotton varieties under cool temperature conditions in the laboratory. The experiment was conducted with 4 replications according to randomized plot design and 14 cotton species (Teks, Stoneville-453, Stone-ville-468, Deltaopal, Deltapine-499, Deltapine-332, BA-119, Carmen, Sayar-314, SureGrow-125, Fan-tom, Berke, Flora and Gloria) were used. The relationship between the germination percentages of the cotton varieties and 100 seed weights (g.100 seed-1), seed density (g.ml-1), water imbibition rate (%), fiber fineness (mic), fiber length (mm), ginning percent (%) and seed cotton yields (kg.ha-1) were determined at cool (18 oC) and normal (30 oC) temperatures in the plant growth cabinet. The germination rate at 30 oC, which was considered the normal germination temperature for cotton plant, was the highest on the 7th day and germination count was the highest on the 14th day when it was germinated at 18 oC which was considered a cool condition. Vigor index of Deltapine-499, Fantom, Stoneville-453, Berke and SureGrow-125 varieties were higher than the others in cool germination conditions (18 °C). When the temperature of germination decreased, the length of germination period was increased in cotton seeds. Germination percentage of the seeds at cool condition was positively correlated with 100 seed weight (r=+0.76, p<0.01), seed density (r=+0.46; p<0.01), seed cotton yield (r=+0.53; p<0.01), fiber fineness (r=+0.77, p<0.01) and water imbibition rate (r=+0.83; p<0.01) while it was negatively correlated with fiber length (r=-0.61; p<0.01) and ginning percent (r=-0.10; p=0.46). It is advisable to take into consideration the parameters such as 100 seed weight, seed density, water imbibition rate, and fiber fineness as an indicator for seed maturity for high germination percentage and vigour. © by PSP.