RESPONS POPULASI Spodoptera frugiperda (J.E. SMITH) (LEPIDOPTERA: NOCTUIDAE) DIPROVINSI JAMBI TERHADAP EMPAT INSEKTISIDA DAN ENAM TANAMAN INANG

RATNA RUBIANA, Prof. Ir. Y. Andi Trisyono, M.Sc., Ph.D.; Prof. Dr. Ir. Witjaksono, M.Sc.; Dr. Suputa, S.P., M.P.

2026 | Disertasi | S3 Ilmu Pertanian

 Ulat grayak jagung (Spodoptera frugiperda) merupakan hama invasif yang berdampak besar pada pertanian di Indonesia. Perkembangan populasi yang cepat, kemampuan beradaptasi pada berbagai tanaman inang, serta indikasi munculnya resistensi terhadap insektisida menjadi tantangan utama dalam upaya pengendaliannya. Oleh karena itu, pemahaman mengenai respons populasi terhadap insektisida serta pengaruh kualitas tanaman inang terhadap performa biologinya menjadi penting untuk mendukung strategi pengelolaan hama yang efektif. Disertasi ini mengkaji tiga aspek utama: (1) tingkat resistensi populasi lapang terhadap empat bahan aktif insektisida (klorantraniliprol, deltametrin, emamektin benzoate, dan spinetoram), (2) dampak konsentrasi subletal klorantraniliprol dan deltametrin terhadap perkembangan, dan dinamika populasi, serta (3) pengaruh enam jenis pakan (jagung, padi, kacang tanah, murbei, rumput pakchong, dan kangkung) terhadap performa pertumbuhan dan indeks nutrisi larva. Hasil penelitian menunjukkan bahwa resistensi ulat grayak jagung bervariasi antarlokasi, dengan Nisbah resistensi (NR) deltametrin mencapai resistensi sedang (NR = 5–7) di beberapa lokasi, sementara emamektin benzoate telah mencapai resistensi sangat tinggi (NR = 17–8.415), sedangkan klorantraniliprol dan spinetoram sebagian besar
masih efektif dengan NR < 5>ini adalah memberikan dasar ilmiah bagi Pengelolaan Hama Terpadu (PHT) yang berkelanjutan, dengan menekankan pentingnya rotasi insektisida berdasarkan perbedaan mode aksi, pemanfaatan tanaman inang yang kurang sesuai, serta integrasi pendekatan agroekologi dalam memperlambat evolusi resistensi. 

Kata kunci: alternatif pakan, konsentrasi subletal, resistensi, toksikologi

The fall armyworm, Spodoptera frugiperda, is an invasive pest that has a major impact on agricultural production in Indonesia. Its rapid population growth, high adaptability to a wide range of host plants, and emerging indications of insecticide resistance present major challenges for effective management. Therefore, understanding population responses to insecticides and the influence of host plant quality on biological performance is essential for developing effective pest management strategies. This dissertation examines three main aspects: (1) the resistance levels of field populations to four insecticide active ingredients (chlorantraniliprole, deltamethrin, emamectin benzoate, and spinetoram), (2) the effects of sublethal concentrations of chlorantraniliprole and deltamethrin on development and population dynamics, and (3) the influence of six host plants (maize, rice, peanut, mulberry, Pakchong grass, and water spinach) on larval growth performance and nutritional indices. The results showed that resistance levels varied among locations. The resistance ratio (RR) to deltamethrin reached a moderate level (RR = 5–7) in several locations, while emamectin benzoate exhibited very high resistance (RR = 17–8,415).
In contrast, chlorantraniliprole and spinetoram remained largely effective, with RR values below 5. Exposure to sublethal concentrations (LC10 and LC25) of
chlorantraniliprole and deltamethrin significantly reduced larval survival (p < 0>cycle to 26–29 days and reduced fecundity to fewer than 150 eggs. The highest efficiency of conversion of ingested food (ECI) was observed on maize (34.6%), while the lowest was recorded on mulberry leaves (17.8%). The main contribution of this dissertation is to provide a scientific basis for sustainable Integrated Pest Management (IPM) by emphasizing the importance of insecticide rotation based on different modes of action, the utilization of less suitable host plants, and the integration of agroecological approaches to slow the evolution of resistance.  

Keywords: alternative host plants, sublethal concentration, resistance, toxicology 

Kata Kunci : alternative host plants, sublethal concentration, resistance, toxicology