Application of the Cotton Varieties Maintaining Program in Egypt to Produce the Nucleolus (Breeder’s Seed) of Super Giza 94 Cultivar, During 2019-2023 Seasons

The present study was carried out during 2019-2023 seasons to produce the breeder’s seed of Super Giza 94 cultivar. At the end of the 2019 season, fifty-six plants representing Giza 94 cultivar type were selected from the nursery to form the increase lines A. In 2020 season, the selfed seeds of the progenies of the 56 selected type plants were grown in number of rows as the amount of seeds allowed conveniently named increased lineA. According to the determination values of both agronomic and fiber characteristics on bulked families of increaseA, 17 families were selected from increaseA to form increase B in 2021. The 17 selected families as well as the three latest strains of Super Giza 94 cultivar were evaluated for yield, yield components and fiber properties. In 2022 season, according to the results of yield trail, the best six families representing the type of Super Giza 94 cultivar were selected from increase B and their selfed seeds were carefully massed together to form increase C. It was planted in an area of about 35 feddans. In 2023 season, it was also propagated as new nucleolus (breeder’s seed) under the name of season (Super Giza 94 nucleolus/2023) in about 332 feddans.The results showed that performing the process of self-pollination with continuous selection, which takes place every season, is considered necessary to maintain genetic purity and eliminate any off-type plants from Super Giza 94 breeding population as a result of highly homozygous in minor genes or recombination among themselves.