Abstract. Supartha IW, Susila IW, Sumiartha IK, Rauf A, Cruz LBDC, Yudha IKW, Utama IWEK, Wiradana PA. 2021. Preference, population development, and molecular characteristics of Spodoptera exigua (Lepidoptera: Noctuidae) on shallot cultivars: A field trial scale. Biodiversitas 23: 783-792. The beet armyworm, Spodoptera exigua Hubner (Lepidoptera: Noctuidae), is a polyphagous insect that is the main pest and is responsible for the decline in shallot production in Indonesia. This study aims to (i) analyze preferences; (ii) colonization time; (iii) population development; (iv) attack of armyworms according to plant phenology in the shallot cultivars; and (v) identification species of armyworms. The research was conducted in Bangli Village, Tabanan Regency, Bali Province, Indonesia. The research design used was a randomized block design with the treatment of five shallot cultivars and five replications. Molecular analysis of armyworm larvae was carried out using the Polymerase Chain Reaction (PCR) method using forward Lep_F1 and reverse Lep_R1 primers at the Cytochrome Oxidase Subunit I (COI) gene. Our results indicate that the period of adult pest infestation has been seen since the emergence of plants, namely 7 days after planting (dap). The colonization period begins at 21 (dap), when plants and larvae begin to grow. The development of the egg and larva population was seen when the plants totaled 21 (dap) (for eggs) and 28 dap (for larvae). The most preferred shallot cultivars are "Bali Karet" and "Bima Brebes". Armyworm larvae, including S. exigua, were identified as related to the same group as isolate larvae from China, India, Pakistan, Thailand, and Japan. These findings indicated that S. exigua preferred the two cultivars of shallots in the fields and emerged at 21 dap. This shows that insect management activities must be carried out systematically both when the shallots plants are young, pre- and post-harvest. Control with natural enemies can also be done for further research.

The aim of this study is to assess the extent of attack and the potential for decreased production of maize types in the field caused to Spodoptera frugiperda. This study was carried out on a large scale, with four treatments and six replications (10 systematic sample replications). Parameters observed include population development, attack rate, the potential for production decline. The results show that this pest attack began to be found in maize 2 weeks after planting (wap) with an average population of 5.37 individu on sweet corn and 6.53 individu on glutinous corn. Furthermore, the population continued to increase up to 5 wap and lowering again to 8 wap. The regression analysis revealed a positive relationship between the larval population and the S. frugiperda attack rate. Sweet corn production decreased by 28.08 percent and glutinous corn output decreased by 25.04 percent, respectively. Overall, our results showed that S. frugiperda attacks continued to increase in both maize varieties (glutinous and sweet), which was indicated by an increase in population and a decrease in production on a field trial scale.

The Growth and Development of the Prabu Bestari Grape Seedling on Various Compositions and Water Content of Growing Media. The growth and development of the grape seedling influenced by the presence of solar and ground water energy.  Prabu Bestari is a originally variety introduced by Balitjestro from Australia after being assembled with the selection process. The need for this variety of agroclimates is in accordance with the North Bali region as a production center.  The bud break in grape plant can be affected by condition of plant media during the seedling procession. Shoot failure in grapes can be caused by the condition of the planting medium in the nursery process. This study aims to determine the growth of grape seedlings that are treated with the use of planting media (soil, soil, chaff, soil + cocopeat, and soil compost) 1: 1 (v / v) mixture ratio. The planting media treatment will be combined with different water content (100%, 75%, and 50% of the field capacity conditions). The study was conducted in a green house at the Experimental Station of Faculty of Agriculture Udayana University from May to August 2018. The research used factorial method (4 x 3) which was designed randomly in groups with three replications. The results showed no interaction on all parameters observed. Increasing length of tendrils (148.16 cm) and number of leaves (26.58 strands) looks better with increasing groundwater content up to 100% of field capacity, whereas the resistant mixture + compost gave the highest increase in tendril length (131.91 cm) and the number of leaves (26.56 pieces). The highest chlorophyll content of the leaves reached 28.68 SPAD unit in a mixture of soil + compost treatment and the lowest was in land use + cocopeat with 18.99 SPAD unit. While the highest leaf chlorophyll content due to water content treatment was shown in 100% of field capacity treatment of 27.84 SPAD unit.

Laporan Baru tentang Distribusi Jamur Entomopatogenik Aschersonia sp. yang Menginfeksi Kutu Putih di Bali. Penelitian tentang distribusi jamur entomopatogenik Aschersonia sp. dilakukan untuk mengetahui persebaran Aschersonia yang menginfeksi kutu putih di seluruh Bali. Penelitian tersebut dilakukan di Kabupaten Gianyar, Bangli dan Buleleng pada centra perkebunan jeruk dimulai tahun 2014 sampai tahun 2018. Aschersonia pertama kali ditemukan pada tahun 2014 di Desa Sekaan Kintamani Bangli dan Desa Kerta Payangan Kabupaten Gianyar, dan pada tahun 2018 ditemukan di Desa Gobleg Sukasada Kabupaten Buleleng. Distribusi jamur tersebut ditemukan di dataran tinggi dan tidak ditemukan di dataran rendah. Hal ini sangat terkait dengan keadaan iklim terutama kelembaban dan suhu. Jamur Aschersonia sangat baik tumbuh pada suhu 20°C yang berada pada dataran tinggi.

Chili is a type of plant that can grow in various types of area, in lowland and highland areas and also can adapt well at a temperature of 24-27 ˚C. The purpose of this research in order to know the influence and effectiveness of the packages technology of Trichoderma sp. mixed with compost, rain shelter and pesticides to control the development of pests in cayenne chili plants and long chili in the highland area. This research was conducted from September 2017 to February 2018, in Pancasari Village, Buleleng Regency, Bali. The study used a Factorial Randomized Block Design with two factors and four times replications. The first factor was  chili type (cayenne chili and long chilli), and the second factor was the use of technologies, compost plus Trichoderma sp., rain shelter, and pesticide. The variable was observed in this research were population of aphis, percentage of fruit fly and yields. The results showed that all treatment technologies effectively suppressed pests development when compared with control. The result show that the damage population of the highest aphis pest was found in control about 194 of Aphids, and population of aphids on pesticide treatment were not found. The result show that damage percentage of the highest fruit fly pest was found in control treatment with the percentage of 76,55% while the lowest percentage was found in pecticide treatment. The rain shelter treatment showed the highest yields were reached 405,87 gr and the control treatment showed the lowest yields were reached 12,03 gr.