Insecticidal Triterpenes in Meliaceae: Plant Species, Molecules and Activities: Part Ⅰ (Aphanamixis-Chukrasia)

Plant-originated triterpenes are important insecticidal molecules. The research on insecticidal activity of molecules from Meliaceae plants has always received attention due to the molecules from this family showing a variety of insecticidal activities with diverse mechanisms of action. In this paper, we discuss 102 triterpenoid molecules with insecticidal activity of plants of eight genera (Aglaia, Aphanamixis, Azadirachta, Cabralea, Carapa, Cedrela, Chisocheton, and Chukrasia) in Meliaceae. In total, 19 insecticidal plant species are presented. Among these species, Azadirachta indica A. Juss is the most well-known insecticidal plant and azadirachtin is the active molecule most widely recognized and highly effective botanical insecticide. However, it is noteworthy that six species from Cedrela were reported to show insecticidal activity and deserve future study. In this paper, a total of 102 insecticidal molecules are summarized, including 96 nortriterpenes, 4 tetracyclic triterpenes, and 2 pentacyclic triterpenes. Results showed antifeedant activity, growth inhibition activity, poisonous activity, or other activities. Among them, 43 molecules from 15 plant species showed antifeedant activity against 16 insect species, 49 molecules from 14 plant species exhibited poisonous activity on 10 insect species, and 19 molecules from 11 plant species possessed growth regulatory activity on 12 insect species. Among these molecules, azadirachtins were found to be the most successful botanical insecticides. Still, other molecules possessed more than one type of obvious activity, including 7-deacetylgedunin, salannin, gedunin, azadirone, salannol, azadiradione, and methyl angolensate. Most of these molecules are only in the primary stage of study activity; their mechanism of action and structure–activity relationship warrant further study.

Prospects of neem and citronella oil against Pseudococcus longispinus (hemiptera: Pseudococcidae) on Phalaenopsis

Synthetic insecticides are still widely used in gardens and greenhouses of ornamental crops to reduce populations of insect pests and preserve flower quality. The improper and unwise use of synthetic insecticides has caused various negative impacts on humans, insect pests, and the environment. Therefore, the quest for unharmed insecticides and environmentally friendly is being sought. The purpose of this study was to examine the effectiveness of botanical insecticide formulation of neem and citronella oil to control long-tailed mealybug Pseudococcus longispinus. Four insecticide concentrations of neem, citronella oil and its mixtures (0.5, 1, 1.5, 2 per cent) were tested for their effectiveness by adding each with Latron at 0.5% as an emulsifier. Bioassays were performed in the laboratory by spraying insecticides on Phalaenopsis leaves infested with P. longispinus groups of one size class, mostly represented by the third instar nymphs. The results revealed that all insecticides tested caused mortality after 24 hours. The combination of neem and citronella in 1.5% provided adequate protection by reducing P. longispinus populations by up to 86%. Thus, botanical insecticides can be recommended as a viable alternative to synthetic insecticides against P. longispinus which infested orchids.

UJI BEBERAPA KONSENTRASI EKSTRAK DAUN MIMBA (Azadirachta indica A. Juss) UNTUK MENGENDALIKAN LARVA Lamprosema indicata F. PADA TANAMAN KEDELAI (Glycine max L. Merill)

The Lamprosema indicata Fabricius larvae is one of the main pests in soybean plantations, which cause up to 80% damage. The alternative control is the use of neem Leafs (Azadirachta indica A. Juss) which have the potential as a botanical insecticide. This research aims to find out the effective concentration of neem Leafs extract to control Lamprosema indicata F. larvae on soybean (Glycine max L. Merill). The research was conducted at the Laboratory Plant Pest and Experimental Farm in the Faculty of Agriculture, University of Riau from May to October 2018. The research was carried out by using a completely randomized design (CRD) with 6 treatments and 4 replications to obtain 24 experimental units. Treatment consist of several concentrations of neem leafs extract 0 g.l-1 water, 20 g.l-1 water, 40 g.l-1 water, 60 g.l-1 water, 80 g.l-1 water and 100 g.l-1 water. The results showed that the concentration of 80 g.l-1 water was effective to control the L. indicata larvae with an initial death time of 5.50 hours and total mortality was 87.50%.

APLIKASI INSEKTISIDA NABATI BERBAHAN TANAMAN RAWA UNTUK MENGENDALIKAN HAMA KEDELAI ULAT GRAYAK (Spodoptera litura) DI LAHAN RAWA PASANG SURUT

One type of pest that often attacks soybean plant leaves in tidal swamplands is the armyworm pest. The intensity of leaf damage due to armyworm attack in tidal swamps ranges from 30-95%, and can even lead to crop failure. In controlling pests in soybean plants in general, always rely on chemical insecticides. The use of these chemical insecticides has a negative impact on the environment. To overcome this, the control is directed towards environmentally friendly pest control by utilizing swamp plants as a botanical insecticide. The study used a randomized block design (RBD) with 3 treatments of swamp plant extracts (galam, kirinyuh, kepayang) and 3 controls, namely without control, botanical insecticide made from neem, chemical insecticide with the active ingredient kloraniliprol. The aim of this study was to obtain a swamp plant extract that could be used in controlling armyworm pests (Spodoptera litura). The results showed that the three types of swamp plants could be used as botanical insecticides in controlling armyworm pests, and has an effectiveness value above 70%. The highest effectiveness of botanical insecticides was obtained at the age of 75 DAP, namely Galam (78.29%), Kirinyuh (78.86%) and Kepayang (78.85%).

Synergistic Interaction between the Entomopathogenic Fungus Akanthomyces attenuatus (Zare & Gams) and the Botanical Insecticide Matrine against Megalurothrips usitatus (Bagrall)

The excessive use of synthetic chemicals for Megalurothrips usitatus (Bagrall) management has resulted in the development of insecticide resistance as well as adverse effects to the natural ecosystem. This has driven the need to develop alternative pest control strategies. This study reports a synergistic interaction between the entomopathogenic fungus Akanthomyces attenuatus (Zare & Gams) and the botanical insecticide matrine against M. usitatus. The results revealed that the germination rate and colony growth of A. attenuatus were inhibited by higher matrine concentrations. Percentage mortalities of M. usitatus following application of A. attenuatus and matrine showed a dose mortality effect. After five days of treatment, all concentrations of matrine combined with different concentrations of A. attenuatus, except one combination (matrine 0.25 mg/mL + 1 × 107 conidia/mL), showed synergistic effect. The activities of acetylcholinesterase and antioxidant enzymes (superoxide dismutase, catalase and peroxidase) in M. usitatus, in response to individual or combined application of A. attenuatus and matrine at the end of the experimental period, were significantly lower than controls. The findings confirm the synergistic action of A. attenuatus and matrine against M. usitatus along with the biochemical phenomenon possibly regulating the synergistic effect.

APLIKASI INSEKTISIDA NABATI BERBAHAN TANAMAN RAWA DALAM MENGENDALIKAN HAMA SAWI DI LAHAN RAWA PASANG SURUT

Vegetables are also needed by the community as a intake of fresh and healthy food to maintain a healthy body, of the many horticultural plants, green mustard/caisin/mustard (Brassica juncea L.) is one of the horticultural crops of vegetables that use their leaves. who is still young. One of the obstacles in the cultivation of mustard is pests and diseases, as for several types of mustard vegetable pests including: small grasshopper pests, Armyworm (Spodoptera litura, plutella (Plutella xylostella), and (Crocidolomia pavonana) With the level of damage to these plants quite varied between 10-25%, some even cause crop failure.From the results of this study it can be concluded that the kepayang, galam and chirinyuh plants can be used as vegetable pesticides in controlling pests of mustard plants in swamps tides, especially for chirinyuh plants, this chirinyuh plant extracts in addition to functioning as a plant-based pesticide also functions as liquid leaf fertilizer, because the mustard plants show larger and greener plants compared to other plant extracts. Keywords: Application, Botanical Insecticide, Mustard Pest.