Peluang Mendapatkan Sumber Ketahanan untuk Hama Penting pada Tanaman Kedelai

Di daerah tropis seperti di Indonesia, tanaman kedelai sangat rentan terhadap berbagai jenis hama. Ragam serangga hama yang menyerang tanaman kedelai sangat banyak dipandang dari spesies maupun familinya. Serangan berat dapat menyebabkan kehilangan hasil 80% bahkan sampai ”puso”. Serangan dapat terjadi sejak tanaman tumbuh sampai menjelang panen, baik secara sendiri maupun secara bersamaan. Salah satu komponen pengendalian hama kedelai adalah penggunaan varietas tahan. Komponen penting dalam rangka membentuk varietas tahan hama adalah tenaga peneliti yang profesional, pengetahuan biologi serangga, tingkat populasi hama, sumber ketahanan (sumber gen tahan), dan metode atau teknik skrining yang tepat. Selain itu perlu penelitian yang lebih mendalam mengenai tingkat ketahanan yang ditemukan pada inang, status hama sasaran (key, occasional, incidental atau potential pest), adanya biotipe dan faktor penentu ketahanan. Berdasarkan beberapa evaluasi yang telah dilakukan di Balitkabi Malang sebelumnya, telah ditemukan sumber-sumber ketahanan terhadap hama pengisap polong, hama ulat grayak dan hama penggerek polong. Galur-galur tersebut adalah IAC-100 dan IAC-80-596-2 yang diketahui mempunyai ketahanan terhadap hama pengisap polong, hama penggerek polong, dan hama ulat grayak. Pada tahun 2003 telah dilepas kedelai varietas Ijen, yaitu galur B4F3WH-177-382-109 yang diperoleh dari persilangan antara varietas Wilis dengan Himeshirazu. Pada tahun 2004 telah ditemukan bahwa galur W/80-2-4-20 (hasil persilangan antara Wilis dengan IAC-80-596-2) mempunyai sifat ketahanan terhadap hama ulat grayak

Peranan Varietas Tahan Hama dalam Pengendalian Hama Terpadu pada Tanaman Kedelai

Di Indonesia, kedelai mempunyai peranan yang penting dalam USAhatani tanaman pangan setelah padi .kedelai bukan komoditas strategis ,tetapi sangat dibutuhkan oleh sebagian besar penduduk untuk menu sehari-hari , pendapatan tunai bagi petani ,dan bahan baku industri .sejumlah serangga hama yang menyerang kedelai mulai saat tumbuh sampai menjelang panen adalah risiko produksi kedelai.Keberhasilan swasembada beras tahun 1984, merupakan salah satu contoh dan faktor yang mendorong penerapan pengendalian hama terpadu (PHT) pada tanaman padi di Indonesia, tetapi pada tanaman kedelai sebagai sistem pengendalian Organisme Pengganggu Tanaman (OPT), program PHT baru dimulai pada tahun 1990-an. Untuk mempercepat penerapan PHT,dilakukan melalui berbagai Latihan Sekolah Lapangan Pengendalian Hama Terpadu (SLPHT) kedelai dan pendidikan lanjutan bagi para PHP di beberapa perguruan tinggi. Program pemuliaan kedelai saat itu, masih ditekankan pada potensi hasil Program pemuliaan tahan terhadap hama belum mendapatkan perhatian karena sistem dan program penelitian masih bersifat fragmentasi dan tujuan jangka pendek. Dengan PHT diharapkan bahwa populasi hama dapat dipertahankan di bawah ambang ekonomi. Penurunan populasi hama dengan pestisida kimia lebih menekankan laju kematian,sedangkan penurunan populasi dengan penggunaan varietas tahan adalah menurunkan laju perkembangan hama (penurunan kesuburan,kepribadian serangga,dan memperlambat pertumbuhan serangga). Varietas tahan dapat dikombinasikan dengan cara atau komponen pengendalian yang lain,sehingga varietas kedelai tahan hama akan meningkatkan stabilitas PHT. Untuk membentuk varietas tahan hama diperlukan kerjasama lintas disiplin,keterpaduan program dan priorita

Evaluasi Galur Kedelai Transgenik Toleran Aluminium Pada Fasilitas Uji Terbatas

Some acid soil is potential for the agricultural development. Constraints for soybean production in the acid soils are Aluminum toxicity and macro nutrient deficiencies. Breeding for soybean varieties tolerant to acid soil is needed. This could be made through genetic engineering, by inserting acid tolerance genes into a soybean genome. Thirty one soybean lines (T0) had been obtained by insertion of Al tolerance genes (MaMt2) through an Agrobacterium mediated transformation, which nine of them contained MaMt2 gene based on PCR test. Further evaluation of those lines was carried out in the Biosafety Containment, where four T1 soybean lines were carrying MaMt2 gene, namely line GM2, GM5, GM10 and GM14. The study was aimed to evaluate the degree of tolerance of T2 generation of GM2, GM5, GM10 and GM14 lines to Al toxicity. Results showed that T2 line were able to grow in hygromicin media, indicating that those T2 lines were containing hygromicin resistant gene (hptII). Phenotypic analysis of T2 lines in four acid soil media treatments indicated that all lines could survive and grow on acid soil without liming and adding compost. GM2 line grew best on the acid medium than did other lines

Expression Of Resistance Of Soybean To The Pod Sucking Bug Riptortus Linearis F. (Hemiptera: Coreidae)

Factors involved in the mechanism of resistance of soybean to pod sucking bug R. linearis were identified using resistant soybean genotypes, IAC-100, and IAC-80-596-2 and the susceptible variety, Wilis as a check. The role of trichomes in resistance was assayed removing trihomes from the pod shell, and seed coat and the resistance was determined based on the number of stylet punctures made by the bug. Seed of IAC-100 and IAC-596-2 that had longer, denser trichomes, higher crude fiber content and suffered fewer stylet punctures than Wilis. This suggested that denser and longer trichomes interfered with stylet piercing of the pod shell. When the trichomes of IAC-100 and IAC-596-2 were removed these genotypes were more susceptible to insect feeding. In further studies, replacement of IAC-100 and IAC-596-2 seed with seed of Wilis in the pods of resistant genotypes resulted less stylet punctures on the Wilis seed. It was concluded that denser and longer trichomes on pods along with harder pod shells acts as a physical barrier in antixenosis resistance of soybean to the pod sucking bug. Therefore, IAC-100, and IAC-596-2 genotypes have good potential for used as resistant parents in a soybean breeding program

Ulat Grayak Spodoptera Litura Fabricius (Lepidoptera: Noctuidae) pada Tanaman Kedelai dan Pengendaliannya

Di Indonesia ulat grayak, S. litura, dapat menyerang berbagai jenis tanaman kacang-kacangan. Bioekologi hama ini telah banyak diketahui termasuk arti ekonomi, dan upaya pengendaliannya. Pemahaman bioekologi ulat grayak perlu diketahui untuk dipakai sebagai salah satu pertimbangan guna menentukan strategi pengendalian ulat grayak yang efektif. Penggunaan insektisida untuk mengendalikan ulat grayak pada tanaman kedelai yang intensif telah banyak dilakukan, namun belum sepenuhnya dapat menekan populasi ulat grayak. Atas pertimbangan biaya, keamanan lingkungan, dan strategi pengendalian hama terpadu maka upaya mencari pengendalian alternatif antara lain: penggunaan musuh alami, dan varietas tahan telah dilakukan. Virus penyebab penyakit Nuclear Polyhedrosis Virus (NPV), pada ulat grayak merupakan entomopathogenic virus yang banyak ditemukan di lapangan dan berpeluang untuk dapat dikembangkan, karena relatif mudah cara penanganannya dibanding dengan penggunaan parasitoid dan predator

Molecular and Phenotypic Analyses of Inpari HDB/K15 F2 Lines Containing sd1 Mutant Gene Resulted from Genome Editing Method

Inpari HDB variety is resistant to bacterial leaf blight (BLB) disease, but due to its tall stature, the variety is susceptible to lodging. Inpari HDB with semidwarf stature, therefore, is of high interest for lodging resistant performance. sd1 gene encoding GA20ox-2 enzyme is one of the genes responsible for imparting semidwarf stature of rice. In previous study, sd1 mutant rice cv. Kitaake (K15) was developed by using CRISPR/Cas9 technology. The objective of this study was to analyze molecularly and phenotypically F2 lines containing sd1 mutant gene resulted from a cross between Inpari HDB and K15 to develop semidwarfInpari HDB rice variety. Thirty F2 Inpari HDB/K15 lines were analyzed at molecular level using DNA sequencing method together with phenotypic assessment of the lines to verify the integration of sd1 mutant gene. DNA sequencing analysis showed that 9 out of the 30 F2 Inpari HDB/K15 lines were sd1 mutants. The remaining F2 lines contained 17 heterozygotes and 4 nonmutants. All the nine mutant lines demonstrated shorter plant stature and showed more tiller number per plant compared to the nonmutant lines. The sd1 mutant gene in the F2 lines showed pleiotropic effects on panicle number andshowed no effects on other traits, such as flowering time, panicle length, filled and unfilled grain percentages. This study showed the introduction of sd1 mutant gene generated semidwarf Inpari HDB lines. The semidwarf Inpari HDB lines obtained from this research should be further evaluated to confirm their lodging resistant performances

Integration of Botanical Pesticide and Entomopathogenic Fungi to Control the Brown Stink Bug Riptortus Linearis F. (Hemiptera: Alydidae) in Soybean

Integration of botanical pesticide and entomopathogenic fungi to control the brown stink bug Riptortus linearis F. (Hemiptera: Alydidae) in soybean. The efficacy of botanical pesticides i.e. Annona squamosa seed powder (ASP) or Jatropha curcas seed powder (JSP) integrated with entomopathogenic fungi, Lecanicillium lecanii to control brown stink bug, Riptortus linearis F. was studied at Muneng Research Station, the Indonesian Legume and Tuber Crops Research Institute (ILETRI) in June up to September 2011. The purpose of the research was to determine the efficacy of integration the natural pesticides i.e, A. squamosa seed powder (ASP) and Jatropha curcas seed powder (JSP) and entomopathogenic fungi L. lecanii to control brown stink bug. The treatments were application of (1) ASP 50 g/l, (2) JSP 50 g/l, (3) ASP 50 g/l + L. lecanii 107/ml, (4) JSP 50 g/l + L. lecanii 107/ml, (5) L. lecanii 107/ml, (6) deltametrin and (7) control (untreated). Application of ASP and JSP combined with L. lecanii decreased the hatched eggs by 84% and 82%, respectively. However, reduction of hactched egg from a single application of ASP and JSP were 56-61% . ASP and JSP combined with L. lecanii reduced both nymphs and adult stink bug population built up and damage (empty pod). Application of ASP and JSP in combination with L. lecanii did not affects the survival of generalist predators such as Paederus sp., Oxyopes sp. and Coccinella sp. as opposed to chemical insecticide that did. The integration of ASP or JSP with entomopthogenic fungi L. lecanii was able to increase the efficacy of brown stink bug control