This research was conducted to evaluate the effectiveness of crab shell powder and chitosan to control Fusarium wilt disease on bananas and to analyze the involved control mechanisms. The effectiveness of crab shell powder and chitosan to F. oxysporum f.sp. cubense was examined in a laboratory (in vitro) and greenhouse (in planta). In vitro evaluation showed that chitosan has an antifungal effect while crab shell powder did not. Application of crab shell powder and chitosan suppressed the disease in green house test. The concentrations of crab shell powder and chitosan that most effective to control Fusarium wilt incidences were 0.25% and 0.10% with an efficacy rate of 66.7% and 83.3%, respectively. The highest disease severity reduction was showed by crab shell powder 0.25% and chitosan 0.50% with an efficacy rate of 56.8% and 59.4%, respectively. Suppression of the disease might be due to the fungicidal effect of chitosan and the increase of the total population of bacteria and chitinolytic bacteria in the rhizosphere when banana seedling roots were treated with crab shell powder or chitosan. Experiment results using the split roots technique exhibited the role of crab shell powder and chitosan potentially to induce the resistance of banana to Fusarium wilt.

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Shallot (Allium ascalonicum var. aggregatum) is one of the most important vegetables which has high economic value with high demand. The increasing of demand must be followed by the increasing of supply with shallot central production optimization at out of Java Island like North Sulawesi. Using the suitable variety with the local agro-ecosystem is the way to optimize shallot production. Lansuna is the new variety which obtained from mass selection of local shallots in North Sulawesi. The objective of this research is to identified the performance of Lansuna as the new variety compared with national commercial variety, Bima Brebes. The research is done through observation method in four village in West Tompaso subdistrict, Minahasa District, North Sulawesi Province. Results of this research showed that Lansuna obviously has better performance compared with Bima Brebes. Lansuna tuber weight per plant is 127.26 g higher than Bima Brebes 76.95 g. Lansuna has a round shape tuber with outer diameter at the center, color of dry tuber skin is N57B (vivid purplish red) and Bima Brebes has oval shape tuber with outer diameter at the bottom, color of dry tuber skin is 61D (deep purplish pink). The agroecosystem condition in North Sulawesi which is at medium until high altitude (600 -1100 above sea level) allegedly very suitable for Lansuna compared with Bima Brebes which usually planted in low altitude (< 500 above sea level). ABSTRAK Bawang Merah (Allium ascalonicum var. aggregatum) merupakan salah satu sayuran penting yang memiliki nilai ekonomi tinggi dengan permintaan yang terus meningkat. Permintaan yang terus meningkat harus diimbangi dengan peningkatan produksi yang dapat dilakukan dengan mengoptimasi sentra produksi yang berada di luar pulau jawa seperti di Sulawesi Utara. Penggunaan varietas yang sesuai dengan agroekosistem setempat merupakan salah satu langkah untuk optimasi produksi bawang merah di Sulawesi Utara. Bawang Merah Varietas Lansuna merupakan varietas baru yang diperoleh melalui seleksi massa dari bawang merah yang ditanam di Sulawesi Utara. Tujuan penelitian ini adalah mengidentifikasi keragaan Bawang Merah Varietas Lansuna sebagai varietas baru dibandingkan dengan varietas komersial nasional yaitu Varietas Bima Brebes. Penelitian dilakukan melalui metode observasi di empat desa di Kecamatan Tompaso Barat, Kabupaten Minahasa, Provinsi Sulawesi Utara. Hasil pengujian menunjukkan bahwa Lansuna memiliki keragaan yang secara nyata lebih baik dibandingkan dengan Bima Brebes. Bobot umbi per tanaman Lansuna lebih besar yaitu 127.26 g dibandingkan dengan Bima Brebes 76.95 g. Bawang Merah Varietas Lansuna memiliki bentuk umbi bulat dengan diameter terluar berada di pertengahan, warna kulit umbi kering adalah N57B (merah keunguan) sedangkan Bima Brebes memiliki bentuk umbi lonjong dengan diameter terluar berada di dekat perakaran dan warna kulit umbi kering 61D (merah muda). Kondisi agroekosistem daerah Sulawesi Utara yang berada di daerah dataran menengah sampai tinggi (600 -1100 mdpl) diduga sangat sesuai un...

The issue of an imbalance in demand and supply of red chili and fluctuating red chili prices have initiated the Ministry of Economy, especially the Deputy for Food and Agribusiness Coordination, to implement a pilot of closed loop partnership model. The partnership is a form of cooperation that is beneficial for parties who have agreed, usually, partnerships are formed and carried out between parties who have agreed and have been bound by an agreement, SOP, or contract. The purpose of this study is there is an impact on the income and farm efficiency of chili farmers in partnership with non-partner farmers in Garut and Sukabumi Regency?. The data analysis carried out includes qualitative data analysis methods that are described descriptively in the analysis of farm performance. The quantitative analysis method used farm income analysis, income and cost comparison analysis (R/C Ratio), and different test analyses to determine the level of efficiency of chili farming commodities by partner and non-partner farmers in Garut and Sukabumi Regency. The results of this study indicate that the profit of closed loop chili farming is more profitable (IDR89.889.654/ha/season with R/C=2,06). Although the productivity and quality of chili produced by closed loop farmers (8,691 tons/ha) is relatively similar to non-closed loop farmers (8,491 tons/ha), it can be seen that the price received by closed loop farmers is higher (IDR15.457/kg) compared to the price received by non-closed loop farmers (IDR11.998/kg). The closed loop partnership model can be considered to have a positive impact on the income and efficiency of chili farming.

High infestation of viruses on shallot's bulb has been reported, although little is known on the effect of virus infection on shallot productivity. The use of virus-free bulbs is assumed to be the key factor to improve productivity. Hot water treatment of bulbs before planting is one of methodologies to eliminate virus from shallot bulbs. Therefore, research was conducted to study the effectiveness of hot water treatment methods of shallots bulbs to reduce virus infections in the field. Field experiment was conducted using split plot randomized block design with two factors. The first factor was the use of netting, i.e. growing shallot in netting house and in open field. The second factor was hot water treatment of shallot bulb at 45 0 C for 15, 30, and 45 min and without treatment. Observations were conducted on the incidence of virus infections, plant growth (number of tillers and plant height) and shallots productivity. Virus infection was confirmed using specific antibodies. Observation of disease symptom indicated that the use of netting house did not significantly suppress the incidence of virus diseases, while hot water treatment significantly reduced the incidence of virus diseases. Hot water treatment for 15, 30 and 45 minutes at 45 0 C was able to suppress virus incidence in the field up to 54.98%, 56.77% and 64.35%, respectively. ABSTRAKInfestasi virus pada umbi bawang merah dilaporkan sangat tinggi, meskipun efek infeksi virus terhadap produktivitas bawang merah masih sedikit diketahui. Penggunaan umbi bebas virus diasumsikan menjadi salah satu faktor utama untuk meningkatkan produktivitas. Perlakuan air panas pada umbi sebelum tanam merupakan metode pilihan untuk mengeliminasi virus. Penelitian dilakukan dengan tujuan mempelajari keefektifan metode perlakuan air panas pada umbi bibit bawang merah terhadap infeksi virus di lapangan. Penelitian disusun menggunakan rancangan acak lengkap petak terbagi dengan dua faktor. Faktor pertama adalah perlakuan rumah kasa dengan dua taraf, yaitu penanaman dalam rumah kasa dan penanaman di lahan terbuka. Faktor kedua adalah perlakuan air panas suhu 45 0 C dengan 4 taraf waktu perendaman, yaitu 15 menit, 30 menit, 45 menit dan kontrol (tanpa perlakuan). Pengamatan dilakukan terhadap insidensi penyakit, parameter pertumbuhan tanaman (jumlah anakan dan tinggi tanaman), dan produktivitas tanaman. Insidensi virus dikonfirmasi dengan deteksi menggunakan antibodi spesifik. Hasil pengamatan gejala menunjukkan bahwa perlakuan rumah kasa tidak berpengaruh nyata terhadap penekanan insidensi penyakit, sementara perlakuan pemanasan berpengaruh nyata terhadap penekanan insidensi penyakit. Waktu perendaman umbi selama 15, 30 dan 45 menit pada suhu 45 0 C dapat menekan insidensi penyakit virus dilapangan berturut-turut sebesar 54.98%, 56.77% dan 64.35%.Kata kunci: eliminasi virus, insidensi penyakit, rumah kasa, waktu perendaman