EFFECT OF SPECIFIC IONS, SALINITY AND ALKALINITY ON YIELD AND QUALITY OF SOME EGYPTIAN COTTON GENOTYPES

Two field experiments were conducted at the Experimental Farm of/ Sakha Agricultural Research Station, during 2017 and 2018 growing seasons. Objective of this investigation was, to study the effect of soil soluble salts, and specific ion effect on seed cotton yield and fiber quality
Five Egyptian cotton genotypes, (G. Barbadence L.); Giza 85, Giza 89 and, new hybrid Giza 86 x 89 (long staple) and Giza 87 and new hybrid Giza 84 (Giza 74 x Giza 68) extra long staple were planted.
The obtained results can be summarized as follows:
1- Seed cotton yield was highly significantly affected by soil salinity level.
2- Significant interaction was observed between different soluble ions, according to simple and partial correlation analysis.
3- Negative correlations were observed between seed cotton yield, and each of Na+, Ca++ and Mg++. The highest negative correlation was obtained with soluble and/or exchangeable Na+ , because of its higher toxicity, in addition to restricting water movement and aeration
4- Negative correlations were shown between seed cotton yield, and each of Cl- and SO--4. It could be noticed that the effect of antagonism between SO--4 and Cl- may depress the toxic effect of the latter.
5- Data revealed negative correlation between exchangeable sodium percentages, and seed cotton yield of some studied cotton genotypes.
6- Highly significantly negative correlations were recorded between ECe, cations (Na+, Ca++ and Mg++), anions (Cl- & SO=4) and each of some studied cotton genotypes characteristics (boll weight, 2.5 Spin length, lint percentage and plant height).