Journal of Applied Entomologist

Potential of molecular marker techniques to identify the susceptibility of some Egyptian cotton varieties to bollworms and whitefly infestation

2026-01-17T10:59:17+00:00

The current investigation was conducted to study the response of six cotton varieties Giza 45, Giza 87, Giza 92, Giza 94, Giza 96 and Giza 97 to infestation of the Pectinophora gossypiella (Saunders), Earias insulana and Bemisia tabaci, the genomic DNA extraction and purification were studied under field conditions at the experimental farm of Sakha Agricultural Research Station, Kafr El-Sheikh Governorate, through 2024 and 2025. Therefore, results showed that, Giza 94 variety was the most susceptibility to infested by P. gossypiella, E. insulana and B. tabaci, while Giza 97 variety was the opposite any the most resistant for the same pests and recorded the number during the two seasons. While, the other varieties of infections are mean. Results showed that the significant differences between Giza 94 and each of the other cotton varieties. Present study can be helpful in selecting resistant varieties in the development of IPM strategies against bollworms and whitefly for good quality production of cotton. Also, this study used ten SCoT primers to generate 130 DNA bands, averaging 13 per primer, with 37 polymorphic bands (41.16% polymorphism). Primers SCoT-1 and SCoT-9 produced the most bands, while SCoT-4 showed the lowest polymorphism, highlighting useful variations for cotton DNA identification.

Study ecology of insects on cocoa (Theobroma cacao L.) plantation with and without insecticide application in North Sumatera, Indonesia

2026-01-24T12:23:50+00:00

This study aimed to analyze the diversity, dominance, evenness, and environmental factors of insects in two different habitat conditions, namely cocoa plantations with insecticide application and without insecticide application in Siantar Marimbun District, Pematangsiantar City. Samples were collected using purposive sampling with yellow sticky traps. A total of 3,649 individuals representing 24 insect species from four orders (Coleoptera, Hemiptera, Hymenoptera, and Diptera) were successfully identified. Hymenoptera was the most abundant order, with Messor barbarus as the dominant species. The Shannon-Wiener diversity index was higher in non-insecticide-treated fields (H1′ = 2.41) compared to insecticide-treated fields (H2′ = 2.28). The dominance index was relatively greater in insecticide-treated fields, while the evenness values in both habitats were categorized as high. The t-test indicated a significant difference in insect diversity between the two habitats (t-value = 3.71 > t-table = 1.96). The measurement results for environmental factors indicate that the temperature ranges from 27.8 to 29.5 °C, the humidity ranges from 69% to 79%, and the wind speed ranges from 1.0 m/s to 1.6 m/s.

A catalogue of tri-trophic associations of aphidophagous arthropods in Gujarat, India

2026-02-13T13:44:09+00:00

The checklist documents 140 predator-aphid-host plant tritrophic associations in Gujarat, involving 43 aphidophagous arthropod species linked to 15 aphid species on 33 host plants across 14 districts. Spiders (Araneae) were represented by 20 species from 10 families, while Coccinellidae (Coleoptera) was the most diverse and dominant insect group, with 13 species accounting for 91 associations. Cheilomenes sexmaculata showed the broadest ecological range (14 aphid species on 29 host plants), followed by Coccinella septempunctata and Coccinella transversalis (seven aphid species each), whereas most other coccinellids exhibited narrow host ranges. Dipteran predators were scarce, represented by Leucopis auraria (Chamaemyiidae) and two syrphids (Eupeodes confrater and Ischiodon scutellaris), together forming nine associations with six aphid species on eight host plants. Chrysopidae (Neuroptera) comprised four species associated with nine aphid species on 14 host plants, yielding 16 associations, with Chrysoperla zastrowi sillemi being the most prevalent. Predators were most frequently associated with Aphis craccivora and Aphis gossypii, while Gossypium hirsutum supported the highest predator diversity. Overall, the dataset underscores the predominant role of coccinellids and spiders in aphid suppression within Gujarat’s agroecosystems. However, the limited representation of dipteran and neuropteran predators, coupled with uneven district-level coverage, reveals substantial gaps in current knowledge and emphasises the need for more comprehensive, systematic surveys across the state.