Hatay ilinde pamuk çeşitleri üzerinde yaprak pireleri [Empoasca decipiens (paoli) ve Asymmetrasca decedens (paoli) (hemiptera: cicadellidae)]'nin popülasyon yoğunluğunun bitkinin fenolojik dönemlerine göre belirlenmesi

BERKAY HALAT

Hatay ilinde pamuk çeşitleri üzerinde yaprak pireleri [Empoasca decipiens (paoli) ve Asymmetrasca decedens (paoli) (hemiptera: cicadellidae)]'nin popülasyon yoğunluğunun bitkinin fenolojik dönemlerine göre belirlenmesi

Thesis Type: Postgraduate

Institution Of The Thesis: Hatay Mustafa Kemal University, Fen Bilimleri Enstitüsü, Bitki Koruma (Yl) (Tezli), Turkey

Approval Date: 2026

Thesis Language: Turkish

Student: BERKAY HALAT

Supervisor: Nihat Demirel

Open Archive Collection: AVESIS Open Access Collection

Abstract:

The purpose of this study was to determine the population density and seasonal fluctuation patterns of the leafhopper species Empoasca decipiens (Paoli) and Asymmetrasca decedens (Paoli) (Hemiptera: Cicadellidae) on different cotton varieties in Hatay Province, Türkiye, in relation to the phenological growth stages of the cotton plant and the leaf pubescence levels of different cotton cultivars. To achieve this, the population dynamics of both species were monitored over two consecutive years using sweep-net sampling in cotton fields. In 2023, sampling was carried out in nine cotton fields located in the Altınözü, Reyhanlı, and Antakya districts, whereas in 2024 the survey was expanded to 50 cotton fields distributed across the Kumlu, Altınözü, Kırıkhan, Reyhanlı, and Antakya districts. The results demonstrated that population fluctuations of E. decipiens and A. decedens were strongly synchronized with the phenological development of cotton. Densities increased markedly during the onset of flowering and reached peak levels during boll formation and boll growth. A year-to-year comparison revealed a substantial rise in total population size in 2024 (719,905 individuals) compared with 2023 (16,125 individuals), likely due to environmental conditions, plant growth characteristics, and broader sampling coverage. Significant variations in population density were observed among cotton cultivars grouped by leaf pubescence level. Hairless leaves (ARMADA) and slightly hairy leaves (MAY455) cultivars observed to support higher pest densities, whereas hairy leaves (BA1010) and moderately hairy leaves (BA911) cultivars exhibited lower population levels. Leaf morphological traits, such as trichome density, glandular or stellate trichomes, and epidermal structures were found to directly influence feeding, movement, and oviposition behavior of leafhoppers. Overall, this study identifies the boll development period as the most critical stage for potential economic damage and underscores the importance of phenology-based integrated pest management (IPM). Cultivar-specific monitoring, economic-threshold-based decision-making during boll development, and the selection of regionally adapted cultivars with advantageous morphological traits are essential for sustainable cotton production in Hatay province.