Species composition and seasonal abundance of some cucurbit insect pests with emphasis on the relative susceptibility of newly produced cabbage and cauliflower cultivars to the prevalent sap-sucking pests in Assiut Governorate, Upper Egypt

Studying the species composition and seasonal abundance of some cucurbit insect pests, with emphasis on the relative susceptibility ofnewly produced cabbage and cauliflower cultivars to the prevalent sapsucking pests in Assiut Governorate, Upper Egypt, was the cornerstone of this investigation. The results revealed 10 arthropod species belonging to 7 families and 4 insect orders in the cabbage and cauliflower plantations. The collected species are divided into 4 groups. The first group contained 5 phytophagous species. The second group contained 1 predatory species. The third group contained 3 predominantly phytophagous (predacious in part) species. However, the fourth group contained 1 parasitoid species. The Hemiptera order contains 40% of the collected species. However, both Thysanoptera and Hymenoptera contained only 10%. Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), were recorded on cabbage in small numbers at the beginning of the season. A gradual increase in the pest numbers was recorded until its lonely peak on March 5, with 22.81, 20.90, and 21.86 individuals/cabbage leaf during the 2024, 2025, and entire periods of study, respectively. The cabbage aphid Brevicoryne brassicae (L.) (Hemiptera: Aphididae) was recorded in low numbers on cabbage at the beginning of the season until mid-March by 1-2 individuals/1 inch2 /cabbage leaf during the 2024 and 2025 seasons. This insect pest exhibited its lonely peak on April 2 on cabbage by 10.83 individuals/1 inch2 /cabbage leaf with a seasonal mean of 5.42 individuals/1 inch2 /cabbage leaf during the entire study period. Similar results were recorded for cauliflower. The mean numbers and population percentages of T. tabaci on cauliflower were higher than those recorded on cabbage. However, B. brassicae presented the opposite results. Regarding the susceptibility degrees, it can be concluded that two cabbage cultivars (Cross El-Fallah and Jumbo Cross Hybrid 1) appeared as susceptible (S) cultivars against both T. tabaci and B. brassicae. However, the crossing cabbage cultivar and all of the tested cauliflower cultivars showed some resistance against both T. tabaci and B. brassicae. Therefore, the authors recommend using cultivars that showed some sort of resistance among advanced breeding programs to produce new cultivars resistant to T. tabaci and B. brassicae.