UJI HAYATI FILTRAT BIAKAN JAMUR ENTOMOPATOGEN YANG DIINKUBASIKAN PADA SUHU 25 oC DAN SUHU 34 oC TERHADAP LARVA Spodoptera litura (FABRICIUS) (LEPIDOPTERA: NOCTUIDAE) PADA CABAI (Capsicum annuum L.) = BIOASSAY OF THE FILTRATE OF ENTOMOPATHOGENIC FUNGAL CULTURE INCUBATED UNDER TEMPERATURE 25 oC AND 34 oC AGAINST LARVAE OF Spodoptera litura (FABRICIUS) (LEPIDOPTERA: NOCTUIDAE) ON CHILLI (Capsicum annuum L.)
Daftar Isi:
- Spodoptera litura is one of important pest of chilli on which the insect can cause damage up to 40%. Entomopathogenic fungi such Beauveria bassiana and Metarhizium anisopliae have been widely used to control S. Litura. Entomopathognic fungi is microorganism usually used as biological control agent producing endotoxin and toxic against insect. There fore, the objective of this research were: 1) knowing the effect of culture filtrate of Beauveria bassiana incubated under temperature 25 oC and 34 oC on the mortality and lethal time of Spodoptera litura larvae, 2) knowing the effect of culture filtrate of Metarhizium anisopliae incubated under temperature 25 oC and 34 oC on the mortality and lethal time of Spodoptera litura larvae. The experiment was arranged in a Completely Randomized Block Design (CRBD) with 2 factors, the first factor was temperature and the second was fungal isolate. Entomopathogenic fungi was incubated under room temperature for 5 weeks then incubated under 25 oC and 34 oC for 7 days, depended on the treatment. The isolates used were 20 isolates consisting of 10 isolates of Beuveria bassiana and 10 isolates of Metarhizium anisopliae. The insect used was second instar of Spodoptera litura, 25 larvae per replicate. Data collected was analyzed using ANOVA. Individual mortality recorded daily was used to determined LT50 using probit analyses. The results showed that the highest mortality caused by isolate B. bassiana was found on the fungus incubated under 25 oC and was significantly different from that of temperature 34 oC. There was an interaction between the first and second factor, means that certain isolate was affected by certain temperature. For isolate factor (second factor), the highest mortality on isolate BTmPc (96%) incubated under temperature 25 oC, and was not significantly different from isolate Btmtr (93.33%), Blepd (90.57%), BTmkt (90.67%) temperature 25 oC,. The significant different was found between isolate BtmGa (74.67%), isolate BMkMs (80.00% ), BPCmS (76.00%), BTmTs (61.00%), Ts1d3 (54.67%), Ts1d2 (61.33%) temperature 25 oC, BTmPc (9.33%), BtmGa (8.00%), Blepd (12.00%), BMkMs (18.67%), BPCmS (14.67%), BTmkt (18.67%), BTmTr (14.67%), BTmTs ( 14.67%), Ts1d3 (14.67%), Ts1d2 (18.67%) temperature 34 oC Under treatment of M. anisopliae, the highest mortality was found on the fungus incubated under temperature 25 oC which was significant different from those of temperature 34 oC, but no interaction between first and second factor. The shortest LT50 of larvae S. litura dropped with culture filtrate of B. bassiana was found on the fungus incubated under temperature 25 oC and significantly different from that of temperature 34 oC. There was no interaction between the first and second factors. The shortest LT50 of larvae S. litura dropped with culture filtrate of M. anisopliae was found on the fungus incubated under temperature 25 oC and significantly different from that of temperature 34 oC. There was no interaction between the first and second factors. For B. bassiana, the highest mortality was found on isolate BTmPc incubated under temperature 25 oC with shortest LT50 (7.51 days), which was not significantly different from isolate BTmTr incubated under temperature 25 oC with LT50 (7.31 days). Therefore, isolate BTmTr incubated under temperature 25 oC was the most effective in killing larvae of S. litura. For M. anisopliae the highest mortality was found on isolate MPdB incubated under temperature 25 oC with shortest LT50 (8.34 days), which was not significantly different from isolate MSwTp2 incubated under temperature 25 oC with LT50 (8.16 days). Therefore, isolate MSwTp2 incubated under temperature 25 oC was the most effective in killing larvae of S. litura.