Toxicity and larvicidal activity on Aedes aegypti of citronella essential oil submitted to enzymatic esterification

The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.

OPTIMALISASI BUDIDAYA TOGA DENGAN PEMBUATAN PESTISIDA ALAMI DAN PEMANFAATAN TANAMAN REFUGIA

ABSTRAKKelompok tani dan masyarakat pedesaan berperan dalam kemandirian kesehatan melalui pengembangan TOGA (Tanaman Obat Keluarga). Namun ada beberapa kendala dalam budidaya TOGA, salah satunya adalah hama tanaman sehingga perlunya dilakukan penanganan hama dengan tepat dan aman dengan pembuatan pestisida alami dan pemanfaatan tanaman refugia. Kegiatan ini bertujuan untuk meningkatkan pengetahuan masyarakat Desa Laban, Mojolaban, Sukoharjo dalam pembuatan pestisida alami dari daun pepaya dan pemanfaatan tanaman refugia dalam rangka optimalisasi budidaya toga. Metode yang digunakan adalah ceramah dan diskusi. Penyuluhan dilaksanakan melalui whatsapp group. Evaluasi keberhasilan dilaksanakan dengan pemberian pretest dan postest sebelum dan sesudah penyampaian materi serta survei kepuasan mengenai tema dan kegiatan pengabdian melalui pengisian kuesioner. Hasil pengabdian menunjukkan adanya peningkatan pengetahuan masyarakat tentang optimalisasi budidaya TOGA dengan cara pembuatan pestisida alami serta penanaman tanaman refugia sebagai pengendali hama, hal tersebut dapat dilihat dari nilai rata-rata pretest dan posttest yang semula 53,71 menjadi 84,00. Hasil evaluasi kepuasan peserta terhadap tema dan kegiatan pengabdian menunjukkan bahwa dari 35 peserta, 42,9% peserta menyatakan sangat puas, 48,6% peserta menyatakan puas, dan 8,6% peserta menyatakan cukup puas dengan kegiatan dan tema pengabdian masyarakat ini. Kata kunci: budidaya; toga; pestisida; refugia. ABSTRACTFarmer groups and rural communities have a role in health independence through the development of medicinal plants. However, there are several detrimental factors in medicinal plants cultivation, such as plant pests, so we need an proper pest management by making natural pesticides and using refugia plants. This community service program aims to increase the knowledge of the people of Laban Village in context of manufacture of natural pesticides from papaya leaves and the use of refugia plants in order to optimize the cultivation of medicinal plants. The methods used are counceling and discussions via whatsapp group. Evaluation of program was carried out by giving a pretest and posttest and survey of satisfaction through filling out questionnaires. The results of the programs show that there is an increase in participants knowledge about optimizing medicinal plants cultivation by making natural pesticides and planting refugia plants as pest control, as indicated by an increase value of the pretest and posttest from 53.71 to 84.00. The results of the evaluation of participants satisfaction with program showed that 42.9% of the participants said it was very good, 48.6% of the participants said good, and 8.6% of the participants said it was good enough. Keywords: cultivation; medicinal plants; pesticides; refuge.

Transcriptional Responses and GCMS Analysis for the Biosynthesis of Pyrethrins and Volatile Terpenes in Tanacetum coccineum

Natural pyrethrins have been widely used as natural pesticides due to their low mammalian toxicity and environmental friendliness. Previous studies have mainly focused on Tanacetum cinerariifolium, which contains high levels of pyrethrins and volatile terpenes that play significant roles in plant defense and pollination. However, there is little information on T. coccineum due to its lower pyrethrin content and low commercial value. In this study, we measured the transcriptome and metabolites of the leaves (L), flower buds (S1), and fully blossomed flowers (S4) of T. coccineum. The results show that the expression of pyrethrins and precursor terpene backbone genes was low in the leaves, and then rapidly increased in the S1 stage before decreasing again in the S4 stage. The results also show that pyrethrins primarily accumulated at the S4 stage. However, the content of volatile terpenes was consistently low. This perhaps suggests that, despite T. coccineum and T. cinerariifolium having similar gene expression patterns and accumulation of pyrethrins, T. coccineum attracts pollinators via its large and colorful flowers rather than via inefficient and metabolically expensive volatile terpenes, as in T. cinerariifolium. This is the first instance of de novo transcriptome sequencing reported for T. coccineum. The present results could provide insights into pyrethrin biosynthetic pathways and will be helpful for further understanding how plants balance the cost–benefit relationship between plant defense and pollination.

Agrobiodiversity of using refugia plants towards several plant gardens at Tulung Rejo, East Java

A study and identificiation on agrobiodiversity of refugia plant as alternative solution by farmers towards their several plant gardens to repel pest was conducted at Tulung Rejo, East Java, Indonesia in March 2021. Refugia plants are biodiversity plants that grow around cultivated plants, which have the potential as a place of protection and a source of food for natural enemy insects (both predators and parasitoids). The principle of refugia pants is that these plants can attract and become a place of life and a source of life for insects, natural enemies of pests. the reseach was using a survey method with interview with farmers who have a land and using refugia plant as a natural pesticides to repel pests of their plants. besides, this research was also using a physical indentification of several refugia plants. Among several locations in Tulung Rejo, the results show that on average farmers use refugia plants of the type of kenikir flower Cosmos caudatus. This has evident because from 20 garden locations, 18 of them use Cosmos caudatus. The needs of farmers in Tulung Rejo, East Java to repel pests naturally.

THE POTENTIAL USE OF ANTI-NUTRITIONAL COMPOUNDS OF GADUNG TUBERS AS BIOPESTICIDES

The use of gadung (Discorea hispida dennst.) tubers as food source is not seen as an attractive option due to dioscorine and cyanide anti-nutritional compounds contained therein. The presence of dioscorine and cyanide compounds makes gadung tubers known as poisonous food. Although the community has known its poisonous nature, the use of gadung tubers as natural pesticides (biopesticides) is not commonly known by the community. Using gadung tubers as biopesticides provides solution to unanswered problems caused by chemical pesticides. This article seeks to describe the potential use of anti-nutritional compounds of gadung tubers as biopesticides based on literature reviews. Various literature related to anti-nutritional compounds contained in gadung tubers and their use as biopesticides have been analyzed in depth. The literature review results show that dioscorine and cyanide anti-nutritional compounds are toxic and can be used as biopesticides. The effectiveness of gadung tubers on various agricultural pests depends entirely on the concentration of gadung tubers used. The use of gadung tubers as biopesticides is needed to increase and maintain the productivity of agricultural land in addition to preserving natural resources.

Strategies for sustainable corn production: a case of South Lampung District, Lampung Province, Indonesia

Demand for corn has been increasing from time to time. However, efforts to increase its production face multidimensional challenges and problems. This study aims to assess sustainability status, analyze leverage and prospective factors, and formulate follow-up strategies for sustainable corn production. Data used primarily were data collected through online focus group discussions and interviews with various related agencies and key informants at provincial and district levels. This study was conducted between May and October 2020 in South Lampung District. Multidimensional Scaling (MDS) and Matrix of Cross Impact Multiplications Applied to Classification (MICMAC) were used to assess the sustainability status and analyze leverage and prospective factors. Then, the Multicriteria Policy (MULTIPOL) was used to formulate the follow-up strategies. The results show that the corn production in South Lampung District is classified as less sustainable, with a sustainability index of 49.30. The sustainability of corn production is influenced by ten leverage attributes, four of which are prospective factors, namely corn prices at the farmer level, the number of water pumps, the use of natural pesticides and fertilizers, and the number of corn shellers. The strategies for sustainable corn production could be carried out by by applying reference purchase prices effectively, strengthening farmer partnerships with the feed industry, supporting environmentally friendly corn farming, and optimization and effective use of pre-harvest and post-harvest machinery. It is necessary to evaluate the effectiveness of various assistance and policies implemented at this time to improve the implementation of programs/policies in the future.

Pengaruh Pestisida Alami Untuk Membasmi Hama Pada Tanaman Cabai di Rumah Petani Karangjati

AbstrakTanaman cabai merupakan tanaman yang banyak dijumpai di Indonesia. Petani melakukan budidaya tanaman cabai karena minat dari masyarakat akan cabai sangat tinggi. Namun petani selalu dihadapkan dengan permasalahan hama yang sering menyerang tanaman cabainya. Kebanyakan petani menggunakan pestisida kimia untuk memberantas hama pada tanamannya. Memang cepat dalam memberantas hamanya, namun kurang baik dalam segi lingkungan dan kesehatan manusia. Untuk itu, penulis akan memberikan alternatif untuk memberantas hama yang ada ditanaman tanpa adanya efek samping baik tanaman itu sendiri maupun ekosistem disekitarnya. Metode yang digunakan dalam kegiatan pengabdian masyarakat ini yaitu observasi dan wawancara. Pembuatan pestisida alami ini menjadi salah satu alternatif karena ramah lingkungan dan aman untuk kesehatan manusia. Pestisida alami ini terbuat dari kotoran kambing, dan rempah-rempah yang sering digunakan ibu dalam memasak. Pestisida ini disosialisasikan kepada masyarakat khususnya yang bergerak di bidang pertanian. Untuk mengetahui efektif tidaknya penggunaan pestisida alami dalam memberantas hama dilakukan dengan pengamatan setelah penyemprotan pestisida alami secara rutin untuk tanaman cabai yang terserang hama. Sehingga dari pengamatan ini didapati penggunaan pestisida dari kegiatan pembuatan pestisida alami, penyemprotan pestisidanya ke tanaman yang terdapat hama, penyemprotan dilakukan sehingga didapati dari hasil pengamatannya pestisida ini cukup efektif dalam memberantas hama yang terdapat di tanaman cabai. Dari hasil pengamatan didapati penyemprotan pestisida alami secara rutin dapat meminimalisir penyebaran hama ditanaman. Kata Kunci: Pestisida Alami, Hama, Tanaman Cabai. AbstractChili plants are plants that are often found in Indonesia. Farmers cultivate chili plants because the public’s interest in chili is very high. However, farmers are always faced with the problem of pests that often attack their chili plants. Most farmers use chemical pesticides to eradicate pests on their crops. It is fast in eradicating the pests, but it is not good in terms of the environment and human health. For this reason, the author will provide an alternative to eradicate pests that exist in plants without any side effects, both the plant itself and the surrounding ecosystem. The method used in this community service activity is observation and interviews. Making natural pesticides is an alternative because it is environmentally friendly and safe for human health. This natural pesticide is made from goat dung, and spices that mothers often use in cooking. These pesticides are socialized to the public, especially those engaged in agriculture. To find out whether the use of natural pesticides is effective in eradicating pests is carried out by observing after spraying natural pesticides on a regular basis for chili plants that are attacked by pests. So from this observation it was found that the use of pesticides from the activities of making natural pesticides, spraying was carried out so that it was found from the observations that these pesticides were quite effective in eradicating pests found in chili plants. From the observations, it was found that regular natural pesticide spraying can minimize the spread of pests on plants.Key Word: Natural pesticides, pests, chili plants.

Changes in "Natural Antibiotic" Metabolite Composition During Tetraploid Wheat Domestication

Plants defend themselves by producing toxins and deterrent metabolites. However, it is unclear how the composition and abundance of these natural pesticides have changed over the course of crop-plant domestication. To address this uncertainty, we characterized differences in secondary metabolites, particularly Benzoxazinoids and its derivates, among four lines of tetraploid wheat: wild emmer wheat (WEW), the direct progenitor of modern wheat; non-fragile domesticated emmer wheat (DEW), which was first domesticated about 11,000 years ago; the subsequently developed non-fragile and free-threshing durum landraces (LD); and modern durum (MD) varieties. Mass spectrometry analyses showed that the metabolome of the embryo of the mature kernel was more complex than that of the endosperm. Clear differences were observed among the metabolic profiles of WEW, DEW, and durum (LD + MD); the metabolic profiles of the two durum lines (LD and MD) were similar. Our results indicated that underappreciated classes of metabolites involved in plant defense mechanisms became significantly more abundant during wheat domestication, while other defensive metabolites decreased or were lost. It may be that the use of industrial pesticides has led to the loss of these endogenous defense metabolites. The re-expression of such “lost” metabolites in modern wheat might help to improve crop resistance, while reducing dependence on harmful industrial pesticides. In addition, we detected alterations in antioxidant composition among wheat lines, as well as increases in levels of plant hormones and antibiotic substances in the more modern lines as compared to the more primitive lines. Here, we show how DIMBOA and its derivates change during wheat domestication, and how this change may effect on the domestication of three taxonomic subspecies of tetraploid wheat (Triticum turgidum).

Antimicrobial activity of methanolic extracts of Vernonia cinerea against Xanthomonas oryzae and identification of their compounds using in silico techniques

Bacterial Leaf Blight (BLB) disease is an extremely ruinous disease in rice, caused by Xanthomonas oryzae pv. oryzae (Xoo). Although various chemicals are available to manage BLB, they are toxic to the environment as well as humans. Hence there is a need to develop new pesticides as alternatives to hazardous chemicals. Therefore, a study was carried out to discover new potent natural pesticides against Xoo from different solvent extracts of Vernonia cinerea. Among all the fractions, the methanolic extract showed the highest inhibition zone. Further, to gain mechanistic insight of inhibitory action, 40 molecules of methanolic extracts were subjected for in silico study against two enzymes D-alanine—D-alanine ligase (Ddl) and Peptide deformylase (PDF). In silico study showed Rutin and Methanone, [1,4-dimethyl-7-(1- methylethyl)-2- azulenyl]phenyl have a good binding affinity with Ddl while Phenol, 2,4-bis(1-phenylethyl)- and 1,2-Benzenedicarboxylic acid, diisooctyl ester showed an excellent binding affinity to PDF. Finally, the system biology approach was applied to understand the agrochemical’s effect in the cell system of bacteria against both the enzymes. Conclusively, these four-hit compounds may have strong potential against Xoo and can be used as biopesticides in the future.