Multienvironment testing is an important phase to study the interaction of G × E and to select stable hybrids for a broad environment or for a specific environment. To study the interaction of G × E and the stability of earliness and yield of Indonesian new sweet corn hybrids under different locations and seasons in West Java, Indonesia, eighteen hybrids were evaluated in six environments in West Java, Indonesia, and were analysed using parametric and nonparametric stability models, additive main effects and multiplicative interaction (AMMI), and GGE biplots. Results showed that the most promising sweet corn hybrids including hybrids G5 (SR 24 x SR 17) and G11 (SR 31 x SR 17) were identified. The parametric and nonparametric stability parameters and ASV were complement to the AMMI and GGE biplots in selecting stable and adaptable hybrids in terms of earliness and yield. G5 was selected as a high-response hybrid for grain yield to Jatinangor (E1, E2), Lembang (E3, E4), and Wanayasa (E5, E6), as well as earliness to Jatinangor (E2), Lembang (E3, E4), and Wanayasa (E5, E6). G5 sweet corn hybrid, therefore, is suggested to be extensively evaluated on farm and produced for smallholder farmers in West Java, Indonesia.

Hybrids that are stable or adaptable in a specific location for the western region of Indonesia are required to increase production of maize in Indonesia. The objectives of the study were (i) to select maize hybrids which are stable or adaptable in the western region of Indonesia and (ii) to determine the discriminant location for evaluating superior hybrids in the western region. Therefore, twelve maize hybrids were planted in different locations and seasons in the western region. Hybrids were selected based on GGE biplot analysis. The results showed that G9 and G10 were stable maize hybrids. G6 was the selected hybrid for the first megaenvironment; whereas, G3 was selected as the hybrid for the second megaenvironment. The L8 and L17 were the discriminant environment for evaluating hybrids in the western region of Indonesia. The high-yielding hybrids selected in this study should be broadly evaluated on-farm in order to disseminate for small holder farmers in Sumatera and Java islands.

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The diazotroph bacteria as ecofriendly biofertilizers play an important role in improving the N status and availability of paddy soil. Laboratory experiment to study nitrogenase activity and IAA production of diazotroph from rice rhizosphere and to assess its effect on the growth of rice seedling has been conducted from September to October 2014 in Agronomy and Horticulture Laboratory Faculty of Agriculture Jenderal Soedirman University, Purwokerto. The experiment was arranged as a completely randomized design and consisted of seven treatments and provided with 4 replications. The treatments were the isolates of indegenous diazotroph (T1 = A11003, T2 = A230041, T3 = A24001, T4 = A230022, T5 = A230021, T6 = A230042 and T7 = without inoculation). The nitrogenase activity measured by acetylene reduction assay method and IAA production was measured by HPLC method. Plant height, leaf greeness, leaf area, total dry weight and total root length were determined on 21 days after sowing. The experimental results showed that the isolat A230021 was identified as Rhizobium sp. LM-5 and have the highest nitrogenase activity at 0.07 µM C2H4 ml -1 h -1 and IAA production reached 19.01 ppm. Inoculation with strains of diazotroph enhanced chlorophyl content, total root length, and biomass production.

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523 Prayoga, M.K. dkk: Preferensi petani terhadap keragaan padi (Oryza sativa) unggul untuk lahan sawah di wilayah Pangandaran dan Cilacap Abstract The object that conducted in this study is farmer's preferences of rice plant characteristics. This study was taken in 3 villages which are village Ciganjeng, village Pamotan, and village Rawaapu. The method used in this study was quantitative design with descriptive analysis. The respondents were 64 rice plant farmers. Measuring instrument used was questionnaire and interview. The result of this study showed that farmers has its own preference for the character of rice plants. Conclution of this study is farmers preferred rice plants which has an average height of plants, wide leaves, leave's surface, leave's angle, and rice straw's type; rice straw that has many branches; strong braches; has a lot rice grains; maturity of rice plants; lenght and wide grains size; non-aromatic; and tender texture. The farmers thought that leave's surface isn't an important character of a rice plants; high of plants, leave's lenght and wide, leave's angle, rice straw's type, grain's lenght and wide, and rice's scent are quite important characteristics; branch's strenght, grain's quantity, and plant's maturity are an important characteristics; resistance to pests, disease resistance, drought resistance, resistance to inundation, salinity resistance, productivity, and rice texture are the most important characteristics. Sari Objek yang dikaji dalam penilitian ini adalah preferensi petani terhadap karakter tanaman padi. Tempat penelitian dilaksanakan di 3 desa yaitu Desa Ciganjeng, Desa Pamotan dan Desa Rawaapu. Desain penelitian menggunakan desain kuantitatif dengan pendekatan analisis data secara deskriptif. Metode yang digunakan adalah survey untuk mengumpulkan data dengan mengedarkan kuisioner dan melakukan wawancara. Jumlah petani yang diwawancarai yaitu 64 orang. Hasil dari penelitian ini adalah petani memiliki preferensi tersendiri terhadap karakter tanaman padi. Kesimpulan dari penelitian ini adalah petani lebih menyukai tanaman padi yang memiliki tinggi tanaman, panjang daun, lebar daun, permukaan daun, sudut daun dan tipe malai yang sedang, cabang malai sekunder yang banyak, ketegaran batang yang kuat, jumlah anakan yang banyak, umur yang genjah, ukuran gabah yang panjang dan lebar, aroma yang tidak wangi, serta tekstur nasi yang pulen. Petani beranggapan bahwa karakter permukaan daun merupakan karakter yang tidak penting; karakter tinggi tanaman, panjang daun, lebar

Respon pertumbuhan dan hasil cabai keriting (Capsicum annuum L.) Ck5 akibat perlakuan pupuk NPK dan pupuk hayatiResponse of growth and yield of curly red pepper (Capsicum annuum L.) Ck5 due to NPK fertilizer and biofertilizer Abstract. This study aims to find out response of growth and yield of curly red chili plant cv. CK5 as a result of NPK and organic fertilizer . The experiment was conducted in Sindanglaya Village, District Sukamantri, Ciamis Regency West Java Province, from August 2017 until January 2018. The experiment design used was Split Plot Design with 4 replications. The main plot was the dosage of NPK fertilizer consisting of two levels : 50% and 100% NPK, and the sub plot was concentration organic fertilizer consisting of three levels : 0%; 0.5%; and 1%. The results showed that : the effect of NPK dosage interaction with concentration of biological fertilizer occurs only at plant height of 28 day after planting, the best treatment was 100% NPK dosage with 0.5% biofertilizer concentration. NPK fertilizer and concentration of biological fertilizers independently affected the amount and weight of fruit. The best dosage of NPK in producing the amount and weight of fruit was 100% NPK, and the best concentration of biofertilizer was 0,5%.

Selection of high yielding and stable maize hybrid requires effective method of evaluation. Multienvironment evaluation is a critical step in plant breeding programs that is aimed at selecting the ideal genotype in a wide range of environments. A method of evaluation that combines a variety parameter of stability could provide more accurate information to select the ideal genotype. The aims of the study were (i) to identify the effect of genotype, environment, and genotype × environment interactions (GEIs) on maize hybrid yields and (ii) to select and to compare maize hybrids that have high and stable yields in diverse environments in Sumatra Island based on combined analysis, selection index, and GGE biplot. The study was conducted in five different environments in Sumatra Island, Indonesia, using a randomized complete block design repeated three times. Data were estimated using combined variance analysis, parametric and nonparametric stability, sustainability index, and GGE biplot. The results showed that the genotype had a significant effect on maize hybrid yields with a contribution of 41.797%. The environment contributed to 24.314%, and GEIs contributed 33.889% of the total variation. E1 (Karo, South Sumatra; dry season) and E3 (Tanjung Bintang, Lampung; dry season) were identified as the most ideal environments (representative) for testing the hybrids for wider adaptability. The maize hybrid with high and stable yields can be selected based on combined stability analysis and sustainability index as well as GGE biplot. These three methods are effectively selected high yielding and stable genotypes when they are used together. The three maize hybrids, namely, MH2, MH8, and MH9, are recommended as high yielding and stable genotype candidates.