Populasi Thrips parvispinus Karny (Thysanoptera: Thripidae) pada bunga tanaman cabai besar di Bali

Serangga hama Thrips parvispinus Karny (Thysanoptera: Thripidae) ditemukan paling dominan menyerang tanaman cabai besar. Serangga ini dapat ditemukan pada semua bagian tanaman cabai, terutama pada bunga dan daun. Serangan berat T. parvispinus pada tanaman cabai besar dapat menyebabkan daun mengalami bercak keperakan hingga kecoklatan dan mengeriting ke arah atas sedangkan bunga yang terserang akan layu dan akhirnya gugur. Tujuan penelitian ini untuk mengetahui populasi nimfa dan imago yang menyerang bunga tanaman cabai besar di Desa Sedang Banjar Belang Kecamatan Abiansemal Kabupaten Badung Bali. Analisis dilakukan di Laboratorium Pengelolaan hama dan Penyakit Fakultas Pertanian Universitas Udayana. Metode yang digunakan adalah survei lapangan dan mengambil sampel tanaman secara diagonal. Hasil penelitian menunjukkan bahwa rerata jumlah populasi imago T. parvispinus selalu paling tinggi pada setiap hari pengamatan dibandingkan dengan populasi nimfa pada bunga tanaman cabai besar. Rerata penurunan populasi imago T. parvispinus mulai terjadi pada pengamatan hari ke-5 hingga hari ke-7. Puncak populasi imago tertinggi terjadi pada hari ke-1 (112,5 ekor) dan populasi terendah terjadi pada pengamatan hari ke-7 (60,75 ekor)

Dinamika Populasi Diaphorina citri Kuwayama (Homoptera: Psyllidae) dan Deteksi CVPD dengan Teknik PCR

The research was conducted in the field of Taro village (600 m above the sea) Gianyar regency and Katung village (1200 m above the sea) Bangli regency and at the Laboratory of Biotechnology Faculty of Agricultural Udayana University in April to October 2009. The purpose of the research were to investigate population dynamic of Diaphorina citri Kuwayama and other insects that were assosiated with citrus cv. siam; and molecular detection of CVPD patogen in its vector, other phytophagous insects on citrus cv.siam and kemuning [Murraya paniculata (L.) Jack.] The result of this study showed that in six month period there was one peak of D. citri population which was associated with the flushing period of citrus at Taro as well Katung villages. The peak of D. citri population of Taro village was higher than that of Katung village. Two species of parasitoids and four spesies of predators were found in the field and may contribute in the suppression of D. citri population. The parasitoids identified were Tamarixia radiata Wat. and Diaphorencyrtus alligharensi Shaffe, whereas the predators were Curinus coeruleus Mulsant, Phiddipus sp., Menochilus sexmaculatus Fabricius and Oxyopes javanus Thorell. T. radiata has been proven to be an effective nymph parasitoid that could suppress the population development of D. citri in citrus orchads. The research revealed that kemuning could serve as a source of infection because it is also a host of CVPD disease as well as of D. citri. Toxoptera citricidus Kirkaldy and Maleuterpes dentipes Hell. were not proven to contain CVPD disease. KEY WORDS: Population dynamic, Diaphorina citri, CVPD, PCR

First Report of Cladosporium dominicanum Zalar, de Hoog & Gunde-Cim. Infecting Whitefly on Ornamental Plants in Bali, Indonesia

As natural enemies, entomopathogenic fungi are essential for controlling certain plant pests, such as whitefly. Many types of entomopathogenic fungi can infect whiteflies, including those from the genera Aschersonia, Metarhizium, Beauveria, and Cladosporium. Currently, there is great interest in using entomopathogenic fungi as an environmentally friendly pest control in organic and sustainable agricultural systems. This study aimed to identify entomopathogenic fungus associated with whiteflies. Identification of entomopathogenic fungus was performed morphologically and molecularly using DNA barcoding with ITS-1 and ITS-4 as primers, in addition to sequencing and phylogenetic tree analysis. Whiteflies infected with entomopathogenic fungus were discovered on ornamental plants (Premna serratifolia, Ficus religiosa, and Ficus rumphii) in Denpasar, Bali, Indonesia from January to March 2023. We found that samples from the field had mycelium that was unbranched or sparingly branched with solitary conidiophores arising terminally from ascending hyphae or laterally from plagiotropous hyphae. Samples from PDA media had ramoconidia with darkened septa, straight and conidia in long branched chains, branching in all directions, conidia were obovoid, ovoid to limoniform. The fungal colonies had the characteristics of being grey-olivaceous, olivaceous-black, and the margins were grey-livaceous to white, gray olivaceous in colony center due to abundant sporulation. In addition, based on the BLAST nucleotide sequence from NCBI GenBank, the insect pathogen phylogenetic tree found in Denpasar, Bali, is in the same clade as Cladosporium dominicanum strain SCAU014, accession number KY827344.1. Based on morphological and molecular analysis the fungus that infects whiteflies on ornamental plants is C. dominicanum

Occurrence of Cassava Lace Bug Vatiga illudens (Drake, 1922) (Hemiptera: Heteroptera: Tingidae) in Bali, Indonesia

Cassava Lace Bugs (CLB) are native pest of cassava (Manihot esculenta Crantz, Euphorbiaceae) to the Neotropical Region, mainly in Brazil. On the other hand, East Java was the first region in Indonesia to record the presence of CLB in 2021, however, it has not been reported in other regions in Indonesia. Therefore, the very importance to recognise the occurrence of CLB in other regions in Indonesia. Based on this, the research has been carried out starting with a field survey, observing behaviour of insect in the field and identify morphologically in the laboratory. The survey results show that the infestation of CLB has been found in lowland, medium, and highland areas in Bali. Symptoms of infestation on the upper leaf surface are small yellow spots with brownish variations. Based on the identification key, CLB from Bali Indonesia, shows a characteristic of a head with a pair of frontal spines. Based on this evidence, the CLB insect can be identified as Vatiga illudens (Hemiptera: Heteroptera: Tingidae). It is the first report of novel distribution areas for V. illudens in Bali, Indonesia. The results of this research are important because V. illudens is one of the main pests of cassava.

Evaluation of the sustainability of groundwater irrigation development in Tejakula and Kubu Districts

The Sustainable Agricultural Irrigation Development Project in Buleleng and Karangasem (SDIABKA) is project activities aim to increase community access to irrigation infrastructure and facilities needed to support increased agricultural productivity and food subregional security in north-east Bali. Institutional developmentof tubwell users group (TUG) have been carried out which in turn will be able to support the management of efficient and sustainable groundwater irrigation facilities both economically and environmentally.It is very important to be known the sustainability of the project such as: Financial independence of the irrigation system, irrigation water supply, and the sustainability status. This valuable experience of developing groundwater irrigation is useful for lesson learned. The target population in this study is 24 SDIABKA TUGs. The TUGs located is in 9 villages in Tejakula and 3 villages in Kubu District

Dinamika Populasi Diaphorina citri Kuwayama (Homoptera: Psyllidae) dan Deteksi CVPD dengan Teknik PCR

The research was conducted in the field of Taro village Gianyar regency and Katung village Bangli regency and at the Laboratory of Biotechnology Faculty of Agricultural Udayana University. The purpose of the research were to investigate population dynamic of Diaphorina citri Kuwayama and other insects that were assosiated with citrus cv. siam; and molecular detection of CVPD patogen in its vector, other phytophagous insects on citrus cv.siam and kemuning [Murraya paniculata (L.) Jack.] The result of this study showed that in six month period there was one peak of D. citri population which was associated with the flushing period of citrus at Taro as well Katung villages. The peak of D. citri population of Taro village was higher than that of Katung village. Two species of parasitoids and four spesies of predators were found in the field and may contribute in the suppression of D. citri population. The parasitoids identified were Tamarixia radiata Wat. and Diaphorencyrtus alligharensi Shaffe, whereas the predators were Curinus coeruleus Mulsant, Phiddipus sp., Menochilus sexmaculatus Fabricius and Oxyopes javanus Thorell. T. radiata has been proven to be an effective nymph parasitoid that could suppress the population development of D. citri in citrus orchads. The research revealed that kemuning could serve as a source of infection because it is also a host of CVPD disease as well as of D. citri. Toxoptera citricidus Kirkaldy and Maleuterpes dentipes Hell. were not proven to contain CVPD disease

The response of sycanus aurantiacus ishikawa et okajima (hemiptera: reduviidae) to color polymorphisms larvae of spodoptera exigua (hubner) (lepidoptera: noctuidae)

his study aims to evaluate the predatory behavior, preference and functional response of S. aurantiacus in color polymorphism larvae of S. exigua. The predatory behavior and preference test of S. aurantiacus  using green and dark brown color larvae  of S. exigua. Functional response test was carried out with 5 treatments of larvae population density with 10 replications. The results showed that S. aurantiacus prefers to dark brown larvae of S. exigua than green. The time taken by predators to find the first and subsequent prey was faster in dark brown larvae than in green, both on low or high larval density. The search time for the first prey on dark brown larvae was 22.7 minutes (at high density) and 39.3 minutes (at low density) while those on green larvae were 26.5 minutes and 42.7 minutes. S. aurantiacus showed type-II functional response to the density rate of S. exigua larvae both dark brown and green with the line equation respectively Y = 1,284x / 1 + 0,056x; R2: 0.96; a: 0,107; Th: 0.52 (dark brown larvae) Y = 1.32x / 1 + 0.063x; R²: 0.952; a: 0,109; Th: 0.58 (green larvae).&nbsp