Determination of Aphis gossypii glover (Hemiptera: Aphididae) population in some cotton varieties in Sur district of Diyarbakır province, Turkey

In addition to negative many factors on yield and quality, plant protection problems also have an important place in cotton (Gossypium spp.) production areas, which is an important agricultural product in both industry and trade sectors all over the world with its different usage areas. The cotton aphid, Aphis gossypii (Glover) (Hemiptera: Aphididae), is one of the main pests of cotton. This study was carried outin order to determine the population development of winged and wingless individuals of A. gossypii on three cotton varieties (May-455, Progen-1010, Progen-Armada) in 2022 cotton fields in the village of Sati, Sur district of Diyarbakır. It was determined that the population fluctuation of the wingless individuals of A. gossypii in the three cotton cultivars in which the study was carried out were similar to each other. The wingless individuals of A. gossypii were first detected on 12.06.2022. The highest population density of the pest; 1.41 individuals/leaf were found on 02.09.2022 in Progen-1010 cultivar, 1,68-1,93 individuals/leaf were found in May-455 and Progen-Armada cultivars on 27.06.2022, respectively. For poultry individuals, the highest density of Progen-1010 variety was 21,6 individuals/trap on 10.09.2022, May-455 variety was observed as 20,6 individuals/trap on 04.07.2022, and Progen-Armada variety was 23,6 individuals/trap on 10.09.2022. The colonies formed by the wingless individuals of the pest in June continue until the middle of July, and the population development of the adults, which turn into winged individuals with the increase in temperature, continues until September-October. Although different densities are observed in cotton varieties for winged individuals, it cannot be said that aphids generally differentiate between varieties. It was determined that the population of wingless individuals of A. gossypii was intense in the climatic conditions of Diyarbakır province in June, while the population of winged individuals increased in September. In this study, it was determined that there was no need for any spraying period against aphids in different cotton varieties and the density did not reach the damage threshold (25 individuals/leaf).