Pathogenicity of Beauveria bassiana Vuill in compost media for Oryctes rhinoceros L. oil palm pest control

The Oryctes rhinoceros pest is an important pest of palm oil plant. Pest problems occur because Oil Palm Empty Fruit Bunches (OPEFB) is added for soil fertility to create a breeding site for larvae O. rhinoceros. Generally, OPEFB will receive the plants more quickly when composted, and pest control is carried out in the compost. Biological control is more recommended because it is environmentally friendly, Therefore compost is added with biological control agent O. rhinoceros namely B. bassiana. This study is aimed to obtain the best conidia density of Beauveria bassiana in compost in controlling larvae O. rhinoceros. The research was carried out at the Plant Pest Laboratory and Experimental Garden, Faculty of Agriculture, Riau of University. The study was carried out from February to November 2020. The experiment on the conidia density of B. bassiana fungi in compost media against larvae O. rhinoceros, using a Completely Randomized Design (CRD), with 6 treatments 4 replications obtained 24 experimental units, while the treatments were 0 g.l-1, 15 g.l-1, 30 g.l-1, 45 g.l-1, 60 g.l-1 and 75 g.l-1. The results of the research revealed that OPEFB compost + sawdust containing the fungus B. bassiana 75 g.l-1 (83,2 x108 kon/ml) had the best ability to control larvae O. rhinoceros with a total larvae mortality of 87% which caused early death of 54 hours after application, LT50 of 213 hours after application, and LC50 of 3,3% or the equivalent of 33 g.l-1 at 14 days after application.

The Effects of Various Doses of Azadirachta indica A. Juss. Seed Cake against Aphis gossypii (Glover) and Growth Characters of Red Chili Plants (Capsicum annuum L.)

Neem plant is used as plant-based insecticide because all parts of the plant have insecticides activities. The utilization of neem plants as plant-based insecticides is generally only in the seed parts, but the extraction of neem seed extract has not been used because it is considered as waste. The utilization of neem seed cake as a natural insectiside is one way to recycle neem seed cake which is known to contain active ingredients of neem seed oil. Apart from its use as an insecticide, neem seed cake can also be used as an organic fertilizer. This study aimed to determine the effect of application of various doses of neem seed cake to A. gossypii on chili plants. The experiment used a randomized block design with 7 treatments and 4 replications. The treatments included control, neem seed cake doses of 25 gr, 50 gr, 75 gr, 100 gr, 125 gr, and a comparative treatment of carbofuran active ingredients. A. gossypii imago were introduced in 20 red chili plants per plant. The results showed the application of a dose of 50 gr of neem seed cake per polybag effectively suppressed A. gossypii populations and gave the best effect on some chili plant growth characters such as leaf chlorophyll content, plant height, leaf hardness of chili plant and levels of N element absorbed.

Role of Cocoa Clones and Endophyte Fungi in controlling VSD Disease in the Field

The fungus Ceratobasidium theobromae is the cause of vascular streak dieback (VSD) in cocoa. VSD disease can cause death in susceptible clones by more than 59%. The use of resistant cocoa clones and endophytic fungi can be an alternative for VSD disease control. The research objective was to evaluate cocoa clones and endophytic fungi to control VSD in the field. The experimental design used was a randomized block design with a factorial pattern. The first factor was cocoa clones, which consisted of clones 45 (K1) and 25 (K2), and the second factor was several types of endophytic fungi. The results showed an interaction between cacao clones and endophytic fungi isolates on the height and number of cocoa leaves. The two cacao clones tested could be naturally infected by C. theobromae without endophytic fungi, with disease incidence of VSD 5, 21% in K1, and 5.75% in K2. The two cocoa clones treated with endophytic fungi, i.e., Paecilomyces sp. EP1, Paecilomyces sp. EP2 and Paecilomyces sp. EP1 + Trichoderma sp.) did not show symptoms of VSD until 20 weeks after planting.

Insecticidal activity of the extracts of Piper retrofractum fruit and Tephrosia vogelii leaf and their mixtures against Crocidolomia pavonana

This laboratory work was carried out to evaluate the insecticidal activity of the extracts of Piper retrofractum (Piperaceae) fruit and Tephrosia vogelii (Fabaceae) leaf and their mixtures against the cabbage head caterpillar, Crocidolomia pavonana. Ground plant materials of the two plant species were extracted separately with n-hexane and methanol. The results of leaf-residue feeding bioassays showed that P. retrofractum (Pr) and T. vogelii (Tv) hexane extracts had strong insecticidal activity against C. pavonana larvae (LC95 < 0.5%) and were more active than their respective methanol extracts. Pr and Tv hexane extract had a moderate and a rather weak contact effect on C. pavonana larvae, respectively. In feeding tests, Pr + Tv (1:1) hexane and methanol extract mixtures indicated synergistic joint effect both at LC50 and LC95 level, whereas in the contact test, the mixture of Pr + Tv (1:1) hexane extract was synergistic at the LC50 level but antagonistic at the LC95 level. In choice tests, antifeedant effects of Pr and Tv hexane extracts at LC25 to LC70 levels on C. pavonana larvae followed a concentration-dependent fashion. Thus, separate or mixed P. retrofractum and T. vogelii extracts are potential alternatives for the control of C. pavonana.

Effect of Anredera cordifolia (Ten) Steenis Leaves Ethanol Extract in suppressing Brown PlantHopper (Nilaparvata lugens Stal.) Populations on Rice Plant

The Brown Planthopper (Nilaparvata lugens Stal.) is one of the pests that often causes rice crop failure in rice. One way to control N. lugens pests is to use of botanical insecticide. The purpose of this experiment is to study the effect of A. cordifolia leaves ethanol in suppressing N. lugens populations. The experiment used a Randomized Block Design (RDB) with 8 treatments and 4 replications. The A. cordifolia leaves ethanol extract concentration tested in this experiment consisted of 0,5%; 0,75%; 1%; 1,5%; and 2%. The results of the experiment showed that the ethanol extract of binahong leaves with a concentration of 1%, 1.5% and 2% cause mortality of N. lugens by 52.50%, 56.25%, and 61.25% on the 14th day after application. Based on the results of this experiment, the ethanol extract of A.cordifolia leaves was not effective against N. lugen.