Judul: Distribution and Genetic Variation of Pest Fall Army Worm Spodoptera frugiperda in Bogor
Abstrak: Spodoptera frugiperda merupakan hama invasif asal benua Amerika yang menyerang tanaman jagung (Zea mays) dan menginvasi Afrika hingga Asia. Dua faktor utama yang mendukung migrasi dan distribusi populasi dari spesies ini adalah kesesuaian habitat dan aktivitas manusia. Keragaman genetik S. frugiperda berdasarkan host strain terdiri atas strain jagung (CS) dan strain padi (RS) yang keduanya dapat di temukan di pertanaman jagung. Di Indonesia, strain tersebut telah ditemukan di Lampung (CS) dan Banten (RS). Gen penanda yang paling akurat untuk mendeteksi strain ini adalah COI dan Tpi, yang terletak di mitokondria (COI) dan kromosom-Z (Tpi). Penelitian ini bertujuan untuk mempelajari variasi gen dari S. frugiperda dan sebarannya di berbagai lanskap di Bogor. Penelitian dilaksanakan pada bulan Juli 2020 hingga Desember 2021 di Kabupaten Bogor, Jawa Barat. Pengambilan sampel dilakukan dengan mengoleksi larva S. frugiperda dari tanaman jagung di berbagai tempat yang berbeda di area Bogor. Sampel larva kemudian dikoleksi dan diawetkan menggunakan alkohol 96% dan kemudian dilakukan ekstraksi DNA. Data distribusi dianalisis menggunakan QGIS dan Google Earth Pro dengan SPSS 20 dan RStudio versi 1.3.1093 untuk analisis statistik dan pembuatan boxplot. Data sekuen DNA disunting menggunakan GeneStudio, aligning menggunakan ClustalW di BioEdit, dan rekosntruksi pohon filogeni menggunakan metode neighbour-joining (bootstrap 1000x) menggunakan MEGA X. Sekuen yang didapat kemudian dibandingkan dengan sekuen autentik dari database GenBank®. Hasil penelitian ini menunjukan kehadiran dari dua strain S. frugiperda di Bogor, yaitu Tpi-C COI-CSh4 dan Tpi-C COI-RS. Penelitian ini juga menemukan bahwa struktur lanskap tidak memiliki efek terhadap variasi gen dari Spodoptera frugiperda., Spodoptera frugiperda is an invasive pest from the American continent that attacks corn (Zea mays) and rapidly invaded Africa to Asia. Two main factors that support migration and population distribution of this species are suitable habitats and human activities. The genetic variation of S. frugiperda based on host strains consists of corn strain (CS) and rice strains (RS), which can be found in corn. In Indonesia, these strains had been found in Lampung (CS) and Banten (RS). The most accurate gene markers to detect these strains are COI and Tpi, located in mitochondria (COI) and chromosome-Z (Tpi). This research aims to study the existing gene variations of S. frugiperda and their distribution in various landscapes in Bogor Regency. The research was conducted from July 2020 to December 2021 in Bogor, West Java. It was carried out by sampling S. frugiperda from corn plants in a different parts of Bogor areas. Larvae samples from each plot were collected and preserved using 96% ethanol, then DNA extraction, DNA amplification, electrophoresis, and DNA sequencing. Distribution data were analyzed by using QGIS and Google Earth Pro programs with SPSS 20 and RStudio version 1.3.1093 for statistical analysis and boxplot construction. Sequence data were edited using GeneStudio, aligned using ClustalW in BioEdit, and the phylogeny tree was reconstructed using the neighbor-joining method (bootstrap 1000x) using MEGA X. The sequence obtained was compared with authentic sequences from the GenBank® database. The results showed the presence of two distinct strains of S. frugiperda in Bogor, Tpi-C COI-CSh4 and Tpi-C COI-RS. The study also found there is no effect of landscape structure
Keyword: COI, invasive species, landscape, Tpi

Judul: Field Survey of Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) on Corn Plants at Regency of Bogor, Sukabumi, Cianjur, and Tangerang
Abstrak: Jagung (Zea mays L.) merupakan salah satu komoditas penting setelah beras sebagai sumber karbohidrat dan pakan ternak. Kendala dalam budidaya tanaman jagung salah satunya diakibatkan oleh serangan hama. Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae) merupakan salah satu hama penting pada pertanaman jagung. Sejak tahun 2019 serangga ini adalah spesies invasif di pertanaman jagung Indonesia. Penelitian ini bertujuan untuk mengetahui persebaran hama Spodoptera frugiperda di Kabupaten Bogor, Sukabumi, Cianjur, dan Tangerang. Survei dilakukan di beberapa lokasi pertanaman jagung dengan jumlah yang berbeda di setiap kabupatennya. Survei meliputi pengamatan dan wawancara kepada petani jagung secara langsung. Beberapa larva dari tanaman yang terserang diambil dan diamati sampai fase pupa untuk mengetahui keberadaan patogen atau parasitoid yang berpotensi sebagai musuh alami di lapang. Serangan hama S. frugiperda terjadi pada tanaman jagung di beberapa lokasi di Kabupaten Bogor yang meyerang tanaman jagung, seperti Desa Cibeber dengan luas serangan mencapai 14.5% dan 17.3% di Desa Cisalada. Luas serangan di Desa Cimapak, Kabupaten Sukabumi 16.6% dan 14.3% di Desa Mekarsari, Kabupaten Tangerang. Serangan S. frugiperda tidak dilaporkan terjadi di Kabupaten Cianjur. Tanaman jagung yang diserang adalah pada bagian titik tumbuh (pucuk tanaman), bunga jagung, daun jagung, dan juga menyerang tongkol jagung. Ditemukan beberapa patogen yang belum diidentifikasi yang berasosiasi dengan S. frugiperda yang dipelihara. Kata kunci: Hama baru, persebaran hama, survei, tanaman jagung., Corn (Zea mays L.) is one of the important commodities after rice as a source of carbohydrate and animal feed. The one of obstacles in the corn cultivation is insect pests. One of the importants insect pests of corn is fall armyworm, Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae). The insect is invasive species on corn plantations in Indonesia since 2019. The aim of this research was to determine distribution of fall armyworm in corn plantation at area of Bogor, Sukabumi, Cianjur, and Tangerang. Survey was conducted in several locations of the corn plantations with different number of location site for each area. The survey includes direct observations of the insect damage and interviews with several corn farmers. Some larvae from the infested plants were collected and it was reared until pupa stage to determine presence of its natural enemies including pathogens or parasitoids that have a potential as natural enemies in the field. The survey result showed that demage of fall armyworm occurred in several corn field locations at Bogor Regency, such as in Cibeber Village with attack area of 14.5% and 17.3% in Cisalada Village; 14.7% of corn field in Cimapak Village, Sukabumi Regency, and 14.3% in Mekarsari Village, Tangerang Regency are reported damaged by this insect. However, there were no evidence that fall armyworm demage occurred at Cianjur Regency during the survey. The part of corn plants that were attacked by fall armyworm were at the growing point (palan shoots), corn flowers, corn leaves, and also attacked the corn cobs. There were unidentified natural enemies associated with the reared insects. Keywords: Corn plantation, new pest, pest attack, pest distribution, survey.
Keyword: Hama baru, Persebaran hama, Survei, Tanaman jagung

Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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