Effect of salicylic acid application on cotton (Gossypium hirsutum L.) yield and fiber quality characteristics

This study was carried out to determine the effect of salicylic acid application on the yield, yield components and fiber quality characteristics of cotton at different growth stages (squaring, flowering and squaring + flowering). The experiment was carried out in 2022 according to the split plot design with 4 replications. Main plot and sub-plots were consist of applications [control (0,0 mM), squaring (1,0 mM), flowering (1,0 mM), squaring (0,5 mM) + flowering (0,5 mM)] and varieties (MAY 455, Stoneville 468, Fiona), respectively. As a result of the statistical analysis, it was determined that salicylic acid applications did not have a significant effect on the investigated characteristics, but the application x variety interaction was significant for the number of days to first boll opening and the number of nodes. There were significant differences among varieties in terms of seed cotton yield, plant height, number of sympodial branches per plant, boll weight, single boll seed cotton weight, number of seeds per boll, number of nodes for first fruiting branch, height/node ratio, ginning percentage, fiber yield, 100 seeds weight, first picking percentage, fiber length, fiber elongation, uniformity, brightness, yellowness and short fiber index, but non-significant differences obtained for number of monopodial branches per plant, number of bolls per plant, normalised difference vegetation index (NDVI value), chlorophyll content (SPAD value), fiber fineness, fiber strength and spinning consistency index. MAY 455 cotton variety had the highest values in terms of seed cotton yield, plant height, boll weight, single boll seed cotton weight, number of seeds per boll, number of nodes to first fruiting branch, fiber yield and 100 seeds weight, while Fiona variety came to the fore in terms of number of days to first boll opening, number of sympodial branches per plant, number of nodes per plant, ginning percentage, fiber length and fiber brightness. Although there was no significant difference between salicylic acid applications in the study, it was determined that there was an increase in yield of 22 kg/da when compared to the control. It has been concluded that the application x variety interaction is significant for the number of days to first boll opening and the number of nodes indicating that varieties show different values depending on the applications.