Judul: Perkembangan Populasi Tiga Hama Utama pada Tanaman Jagung (Zea mays L.)
Abstrak: Corn is an important cereal crops as a carbohydrate source for millions people in the world. That also a biggest part of people menu in developing countries. The main pests of the often problem in the cultivation corn are Rhopalosiphum maidis Fitch (Hemiptera: Aphididae), Ostrinia furnacalis Guenee (Lepidoptera: Pyralidae) and Helicoverpa armigera Hubner (Lepidoptera: Noctuidae). The aims of this study is to determine population growth and attack of aphids R. maidis, O. furnacalis, H. armigera on corn plantation. Observation of three types pests implemented on 10 plots of planting corn, each plot measuring 4 m x 5 m. Observations were made on vegetative and generative plant of maize. The observations result indicate that the population density of aphids R. maidis peaked at the age of 49 days after planting, while the natural enemies of the family Coccinellidae reach peak population at the age of plants 65 days after planting. Larvae O. furnacalis and H. armigera start found on corn cobs at age 59 days after planting. The both of pest attack symptoms can be distinguished, O. furnacalis make holes on the ends of cob and elongate, while H. armigera borer on tip of the corn cob and eat the kernel on the ends of the corn cob. The intensity of damage result by O. furnacalis and H. armigera on corn cobs is low and didn't give real effect to production. Production of corn, from the stem were attacked by O. furnacalis is not significantly different with the production of healthy stems.
Keyword: Rhopalosiphum maidis, Ostrinia furnacalis, Helicoverpa armigera, corn, cob

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: Penentuan energi aktivasi ion untuk melewati membran teflon pada berbagai larutan elektrolit
Abstrak: Kaseno (1999) menyatakan bahwa dalam teknologi pemisahan, membran adalah bahan yang dapat memisahkan dua komponen dengan cara yang spesifik yaitu menahan atau melewatkan salah satu komponen lebih cepat dari komponen lainnya. Kemampuan pemisahan yang dimiliki oleh membran untuk melewatkan suatu senyawa kimia atau molekul diakibatkan oleh adanya perbedaan sifat fisika atau kimia antara membran dengan senyawa kimia.
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