Toksisitas dan bioaktivitas ekstrak daun suren Toona sureni terhadap ulat grayak Spodoptera litura

RACHMAWATI, Jeti, Prof.Dr.Ir. Edhi Martono, M.Sc

2005 | Tesis | S2 Ilmu Hama Tumbuhan

Penelitian ini bertujuan untuk mengetahui toksisitas, dan bioaktivitas ekstrak daun suren (Toona sureni) terhadap Spodoptera litura. Uji toksisitas dilakukan dengan metode uji pakan dengan konsentrasi 100; 50; 25; 12,5; 6,25; 5,0; 2,50; 1,25 dan 0%. Masing-masing perlakuan menggunakan 20 ekor larva dan dilakukan 3 ulangan. Pengamatan dilakukan dengan mengamati mortalitas larva pada 24, 48 dan 72 jam setelah perlakuan. Uji bioaktivitas meliputi uji aktivitas antifeedant dengan metode uji pilihan dan uji aktivitas penghambat pertumbuhan dan perkembangan. Uji aktivitas antifeedant dengan menggunakan 10 ekor larva, dilakukan 3 ulangan, dan pengamatan pada 48 jam setelah perlakuan. Uji aktivitas penghambat pertumbuhan dan perkembangan dengan konsentrasi 6,25; 5,00; 2,50 dan 0,00%, menggunakan 10 ekor larva dan dilakukan 3 ulangan. Pengamatan dilakukan untuk mengamati pertumbuhan dan perkembangan larva. Analisis data mortalitas dan uji aktivitas penghambat pertumbuhan dan perkembangan menggunakan Anova dan dilanjutkan dengan Uji Duncan pada taraf kepercayaan 5%, sedangkan analisis uji aktivitas antifeedant menggunakan uji t pada taraf kepercayaan 5%. Hasil analisis statistik menunjukkan bahwa ekstrak daun suren bersifat toksik terhadap larva S. litura instar kedua, dengan nilai LC50 dan LC90 ekstrak daun suren terhadap S. litura sebesar 4,86% dan 50,32%. Ekstrak daun suren 100% dapat menghambat aktivitas makan larva S. litura instar ketiga sebesar 35,1%. Ekstrak daun suren konsentrasi 6,25% dapat menghambat pertumbuhan dan perkembangan S. litura dengan indeks pertumbuhan (GI) sebesar 0,43 dan indeks pertumbuhan relatif (RGI) sebesar 0,57, menurunkan berat larva, meningkatkan penghambatan pertambahan berat larva, memperpanjang umur periode larva, menurunkan berat pupa betina, pembentukan pupa dan imago.

This research was aimed to determine the toxicity and bioactivity of suren (Toona sureni) leaves extract to Spodoptera litura. Toxicity assays was carried out using feeding method using serial concentrations of 100; 50; 25; 12.5; 6.25; 5.0; 2.5; 1.25 and 0%. Each treatment were used 20 larval and replicated three times. Observation directed to observe larval mortality at 24, 48, 72 hours after treatment. Bioactivity assay included antifeedant assay using choice method and growth and development inhibition assay. Antifeedant assays were carried out using 10 larvae, replicated three times, and observed 48 hours after treatment. Growth and development inhibition assays using concentration of 6.25; 5.0; 2.5 and 0% respectively, were carried out using 10 larvae and replicated three times. Observation were directed to observe growth and development of larva. Data mortality and growth and development inhibition assays were analyzed using Analysis of Variance (ANOVA) and continued by Duncan Multiple Range Test (DMRT) at significance level 5%, while antifeedant activity test were analyzed using t test at level 5%. Statistical analysis showed that suren leaves extract were toxic to the 2nd instar of S. litura larva, with LC50 and LC90 values of 4.86% and 50.32%. Concentration of leaves extract 100% were able to inhibit feeding activity of S. litura 3rd instar larval at the rate 35.1%. Concentration of leaves extract 6.25% were able to inhibit growth and development of S. litura with growth index (GI) 0.43 and relative growth index (RGI) 0.57, decreasing larval weight, increasing inhibition gain weight of larval, lengthening larval age, and decrease female pupal weight, pupal formed and adults emerged.

Kata Kunci : Hama Tanaman,Ulat Grayak S Litura,Toksisitas Daun Suren, Toxicity, bioactivity, extract suren (Toona sureni) leaves, Spodoptera litura