Genotype X environment interaction and stability analysis of cotton yield in Aegean region of Turkey.

The objective of this study was to determine genotype X environment (GE) interaction and stability of cotton genotypes, and effect of different environments on seed cotton yield to understand its adaptation to varying environments. Fourteen cotton genotypes were evaluated at four locations across Aegean region of Turkey in 1997 and 1998. Genotypes were tested by two stability parameters as linear regression coefficient (b) and deviations from regression (S2d). Significant differences were observed for the mean yields in the 8 environments. Mean seed cotton yield ranged from 4.58 to 5.80 t ha(-1). Genotypes showed significant interaction with environments. Regression coefficients ranged from 0.23 to 1.46, and deviations from regression were significant for only four genotypes. It was concluded that three high yielding cotton genotypes SG-1001, SG-125 and DLP-5409 were found to be stable genotypes.

Effects of potassium humate solution and soaking periods on germination characteristics of undelinted cotton seeds (Gossypium hirsutum L.).

The present study was conducted to determine the effects of soaking in potassium humate (PH) solution (55% humic acid, 30% fulvic acid and 8% potassium hydroxide) and distilled water (DW) for different periods (0, 4, 8 and 16 hours) on germination characteristics of undelinted seeds of cotton cv Ersan-92. Radicle, hypocotyl and seedling length, radicle and hypocotyl elongation rate and vigor index increased by PH solution treatment and increasing soaking periods. The medium x soaking period interactions were significant except for germination percentage. Sixteen hour soaking period gave the highest values of investigated characteristics. It is suggested that pre-sowing PH solution treatment may be useful to provide a good stand establishment.