Electronic Theses and Dissertation

Jagung manis (Zea mays saccharata Sturt.) merupakan komoditas pertanian yang semakin populer di Indonesia, namun produktivitasnya kerap terhambat oleh serangan hama seperti ulat grayak, penggerek batang, dan penggerek tongkol. Penggunaan pestisida kimia sintetik secara berlebihan untuk mengatasi hama tersebut menimbulkan dampak negatif terhadap lingkungan dan kelangsungan hidup musuh alami. Salah satu usaha untuk menurunkan serangan hama yang ramah lingkungan adalah melalui pemanfaatan tanaman refugia, yaitu tanaman berbunga yang berfungsi sebagai habitat dan sumber pakan bagi musuh alami (predator dan parasitoid) sebagai agens pengendalian hayati. Penelitian ini bertujuan untuk mengetahui pengaruh perbedaan warna bunga tanaman refugia terhadap keanekaragaman musuh alami pada pertanaman jagung manis.
Penelitian dilaksanakan di Desa Miruek Lamreudeup, Kecamatan Baitussalam, Kabupaten Aceh Besar, dan Laboratorium Pengendalian Hayati Fakultas Pertanian Universitas Syiah Kuala sejak November 2025 sampai April 2026. Metode yang digunakan adalah Rancangan Acak Lengkap (RAL) non faktorial dengan 4 perlakuan, yaitu tanaman jagung manis tanpa refugia (R0), dengan bunga refugia berwarna kuning (R1), dengan bunga refugia berwarna merah (R2), dan bunga refugia berwarna kuning dan merah (R3). Pengambilan sampel serangga dilakukan sebanyak 6 kali dengan interval 7 hari menggunakan pitfall trap, sweeping net, dan metode manual. Identifikasi dan pengamatan lanjutan dilakukan di Laboratorium Pengendalian Hayati Fakultas Pertanian Universitas Syiah Kuala. Peubah yang diamati meliputi komposisi spesies, kekayaan spesies, kelimpahan individu, keanekaragaman (H'), kemerataan (E), dominansi (D), dan indeks similaritas musuh alami.
Hasil penelitian menunjukkan bahwa perbedaan warna bunga tanaman refugia berpengaruh nyata terhadap kekayaan spesies, keanekaragaman, dan dominansi musuh alami. Sebanyak 21 spesies musuh alami dari 7 ordo dan 12 famili ditemukan, terdiri atas 20 spesies predator dan 1 spesies parasitoid, dengan ordo Hymenoptera sebagai yang terbanyak dan Dolichoderus thoracicus sebagai spesies paling melimpah (310 individu). Berdasarkan uji ANOVA dan BNT taraf 5%, refugia bunga kuning (R1) memberikan hasil terbaik dengan kekayaan spesies tertinggi (13,5 spesies) dan indeks keanekaragaman tertinggi (H' = 2,29), serta berbeda nyata dibandingkan kontrol. Refugia juga menurunkan dominansi spesies secara nyata (P = 0,027), dengan nilai dominansi terendah pada R1 (0,1267) dan tertinggi pada kontrol (0,2167). Sebaliknya, refugia tidak berpengaruh nyata terhadap kemerataan spesies (P = 0,651) maupun kelimpahan individu (P = 0,129). Analisis similaritas menunjukkan bahwa refugia berwarna kuning menghasilkan komposisi spesies musuh alami yang paling berbeda dibandingkan kontrol, sehingga menunjukkan kemampuan yang lebih baik dalam menghadirkan spesies musuh alami baru dibandingkan refugia berwarna merah maupun kombinasi refugia kuning dan merah. Dengan demikian, penggunaan refugia berwarna kuning (Tagetes erecta) lebih direkomendasikan untuk mendukung konservasi musuh alami dan penerapan Pengendalian Hama Terpadu (PHT) pada pertanaman jagung manis. Penelitian selanjutnya disarankan menanam refugia langsung di tanah agar pertumbuhannya lebih optimal dibandingkan menggunakan polybag.

Sweet corn (Zea mays saccharata Sturt.) is an increasingly popular agricultural commodity in Indonesia, but its productivity is often hampered by pest infestations such as armyworms, stem borers, and earworms. The excessive use of synthetic chemical pesticides to control these pests has negative impacts on the environment and the survival of natural enemies. One environmentally friendly approach to reducing pest infestations is the use of refuge plants—flowering plants that serve as habitats and food sources for natural enemies (predators and parasitoids) acting as biological control agents. This study aims to determine the effect of differences in refuge plant flower color on the diversity of natural enemies in sweet corn fields. The study was conducted in Miruek Lamreudeup Village, Baitussalam Subdistrict, Aceh Besar Regency, and at the Biological Control Laboratory of the Faculty of Agriculture, Syiah Kuala University, from November 2025 to April 2026. The method used was a non-factorial completely randomized design (CRD) with four treatments: sweet corn without refugia (R0), with yellow refugia flowers (R1), with red refugia flowers (R2), and with both yellow and red refugia flowers (R3). Insect sampling was conducted six times at 7-day intervals using pitfall traps, sweeping nets, and manual methods. Identification and further observations were carried out at the Biological Control Laboratory of the Faculty of Agriculture, Syiah Kuala University. The variables observed included species composition, species richness, individual abundance, diversity (H’), evenness (E), dominance (D), and the natural enemy similarity index. The results showed that differences in the flower color of refuge plants had a significant effect on species richness, diversity, and the dominance of natural enemies. A total of 21 natural enemy species from 7 orders and 12 families were found, consisting of 20 predator species and 1 parasitoid species, with the order Hymenoptera being the most abundant and Dolichoderus thoracicus being the most abundant species (310 individuals). Based on ANOVA and BNT tests at the 5% significance level, the yellow-flowered refugia (R1) yielded the best results with the highest species richness (13.5 species) and the highest diversity index (H' = 2.29), and differed significantly from the control. The refugia also significantly reduced species dominance (P = 0.027), with the lowest dominance value observed in R1 (0.1267) and the highest in the control (0.2167). Conversely, the refugia had no significant effect on species evenness (P = 0.651) or individual abundance (P = 0.129). Similarity analysis showed that yellow refugia produced the most distinct composition of natural enemy species compared to the control, indicating a greater ability to introduce new natural enemy species than red refugia or a combination of yellow and red refugia. Thus, the use of yellow refugia (Tagetes erecta) is more highly recommended to support the conservation of natural enemies and the implementation of Integrated Pest Management (IPM) in sweet corn cultivation. Future research is encouraged to plant refugia directly in the soil to optimize growth compared to using polybags.