G‘O‘ZA NAVLARINI BIOLOGIK XUSUSIYATLARINI YAXSHILASH

The percentage of crossbreeding of local cotton varieties with foreign cotton varieties in F0 hybrids was 6.6% lower than the percentage of crossbreeding of foreign cotton varieties with local cotton varieties. It was found that the boll weight of cotton in samples obtained from crossbreeding of foreign cotton varieties with local varieties was 20.0% lower in upland cotton and 13.0% lower in long staple cotton samples compared to samples obtained from crossbreeding of local varieties with foreign varieties in F0 hybrids. Compared to the boll weight of cotton of F1 hybrids obtained by crossing local varieties with foreign varieties, the boll weight of cotton of F1 hybrids obtained by crossing foreign cotton varieties with local varieties was 10.9% greater in upland cotton and 23.3% less in long staple cotton, the weight of 1000 cottonseeds was 2.9% lighter in upland cotton and 10.9% heavier in long staple cotton, the fiber length was 2.6% shorter in upland cotton and 6.2% shorter in long staple cotton, and the fiber length was 2.6% shorter in upland cotton and 9.4% longer in long staple cotton. Observations revealed that the transfer of maternal traits was dominant in crossing. Therefore, it is advisable to use the combinations of crossing with the mother to transfer the positive traits of a variety to hybrids.