Gene action and stability of egyptian coton tield (gossypium barbadnse L.)under wady seder conditions

Three field experiments were carried out at Ras Sudr Agriculture Station of Desert Research Center, South Sinai during three successive seasons of 2000, 2001and 2002. The results revealed highly significant differences among genotypes for yield contributing characters under four salinity levels i.e., 2000, 4000, 6000 and 8000 ppm. However, increasing salinity levels resulted in a reduction of all studied traits, except fiber fineness and concentration of magnesium, sodium and proline which were increased as a result of salinity elevation. It is evident also that, under salinity stress conditions, correlation was positive and significant between seed cotton yield/plant and each of potassium and proline contents in both 1st and 2nd seasons and between boll weight and proline content in 1st one. Also, salinity sensitivity index for lint yield/fed. and boll weight was positively and significantly correlated with sodium concentration in the 1st season