No abstract

Effectiveness of botanical insecticide formulations against cocoa pod borer Conopomorpha cramerella (Snell.). Cocoa pod borer (CPB), Conopomorpha cramerella (Lepidoptera: Gracillariidae), is a major pest on cocoa plants. The research aimed atfinding out botanical insecticide formulations that are effective against CPB. Plant materials used for preparing the formulations were cashew nut shell (Anacardium occidentale), whiteflower albizia (Albizia saponari), siam weed (Chromolaena odorata), and candle bush (Senna alata) extract. This research was conducted in the field using a randomized complete block design with the following treatments: formulation of cashew nut shell extract, cashew nut shell extract + whiteflower albizia bark extract, cashew nut shell extract + siam weed leaf extract, cashew nut shell extract + candle bush leaf extract, cashew nut shell extract + whiteflower albizia bark extract + siam weed leaf extract + candle bush leaf extract, and a synthetic insecticide formulation containing a mixture of lambda-cyhalotrin 106 g/L and thiametoxam 141 g/L as well as control (without botanical and synthetic insecticide treatment). The concentration of botanical pesticides applied from cashew nut shell extract used was 2.5 mL/L, while from other ingredients 250 mL/L.Variables observed were intensity of CPB infestation, degree of damage to the cocoa seed, and the efficacy of botanical insecticide treatments. The results showed that the test botanical insecticide formulations reduced the intensity of CPB infestation by 48.9–55.3% and the degree of seed damage by 52.3–58.2% compared with control. The efficacy of the test botanical insecticide formulations in controlling CPB was relatively the same when compared to each other, with a range of efficacy of 64.2–71.0%, but was lower than that of the synthetic insecticide formulation (92.8% efficacy). The implication of this research is that botanical insecticide formulations have the prospect of being continuously developed and have the potential to reduce the used of synthetic insecticides.

Effectiveness of several media for propagation biological agent Trichoderma sp.. This study aims to investigate at the effectiveness of some media to propagation of Trichoderma sp. and to determine the effectiveness of the media that has the best propagation of Trichoderma sp. This research consists seven treatment propagation medium; media dregs sago, dregs of the cashew nut shell, sawdust, maize, bran, rice, and husk. The results showed that the medium used for propagation Trichoderma sp. have varying effectiveness. The most effective media for propogation Trichoderma sp. was media bran, with growth capability Trichoderma sp on 4 days after incubation (100%), the difference in weight of the media before and after incubation Trichoderma sp. was 2,04 g and the number of conidia was 104,125.10 3 /g media.

Sclerotium rolfsii is an important plant pathogen and causes disease in some cultivated plants especially in Southeast Sulawesi. S. rolfsii is mainly controlled by using synthetic fungicides which are hazardous to human, livestock and environment. In the present study, eleven species of Trichoderma, indigenous to Southeast Sulawesi, were tested for their in vitro efficacy against S. rolfsii to replace deleterious fungicides. The analysis of variance showed significant results of the indigenous Trichoderma spp. against S. rolfsii. in in vitro test. All the Trichoderma isolates inhibited the growth of the test fungus differently. After three days of inoculation, ST1 treatment showed the highest inhibitory ability by 55.56% but was not significantly different from the inhibitory abilities of ST2, ST3, ST5, ST6, ST7, ST9, ST10, and ST11 treatments. The treatment ST4 and ST8 gave inhibitory abilities by 25.22% and 26.11% respectively. Furthermore, the data after 4, 5, 6 and 7 days after inoculation were also significant. The ST1 (DKT isolate) treatment gave the maximum inhibition of the test fungus after all the time intervals of seven days. On the other hand, ST8 (LKP isolate) treatment gave the lowest inhibitory ability. DKT isolate of indigenous Trichoderma had the highest inhibitory ability reaching to 55.56% on third days of observation while LKP isolate had the lowest inhibitory ability of 16.67% and then decreased subsequently. the antagonistic mechanisms of Trichoderma isolates were space and nutrition competition, antibiosis, and mycoparasitism. These results showed that Trichoderma indigenous to Southeast Sulawesi had better in vitro inhibitory ability to control S. rolfsii by the above-mentioned mechanisms.