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.

Indonesia is known as a country with high biodiversity in the world. Plenty of beneficial-rich plants grow in Indonesia as a country that has tropical climate, one of the plant is tarum (Indigofera tinctoria Linn.). Tarum is a natural dye-producing plant whose presence is not widely known. The development of human needs, especially in meeting the needs of natural dyes, is considered to be the main reason for reintroducing tarum as a suitable plant to grow in Indonesia. The use of natural dyes in addition to being safe for humans is also safe for the environment, considering the substances produced by the tarum plant are widely used as textile dyes. Good enough environmental compatibility makes this plant actually spread in many parts of Indonesia, especially in Java. It is necessary to possess a knowledge about the right cultivation techniques for tarum plants in an effort to increase the color-producing substances in plants. The attempts to obtain information about cultivation techniques are an opportunity to re-raise these plants to be better known and developed as potential plants.

Pemanfaatan beberapa jenis urin ternak sebagai pupuk organik cair dengan konsentrasi yang berbeda pada tanaman kelapa sawit (Elaeis guineensis Jacq.) di pembibitan utama Utilization of livestocks urine as a liquid organic fertilizer with different concentrations on oil palm (Elaeis guineensis Jacq.) in main nursery Abstract. Seedling is an initial stage in the cultivation of oil palm, seed quality will affect the results that will be obtained later. Factor affecting the growth of seedlings of which the availability of nutrients which can be obtained from inorganic and organic fertilizer. Application of inorganic fertilizer without an organic fertilizer balanced can be damage the nature of the soil, necessitating organic fertilizer the urine of livestocks as organic liquid, adding organic liquid fertilizer to the soil, can help the plants to growth because organic liquid fertilizer of livestocks urine contain growth hormone for plants and easily absorbed to the plants. The research was conducted in Experimental Station of Ciparanje, Faculty of Agriculture, Padjadjaran University, Sumedang, from September 2017 to February 2018. Ordo of the soil used is Inceptisol. Precipitation type according to Schmidt and Ferguson's classification of type C with ± 780 meters above sea level altitude. Experiment was using a randomized block design (RBD) with 11 treatments with 3 replications and the number of plants in each plot of 2 plants. The treatment consists the urine of cows, goats and rabbits with some concentration of 40 mL/L of water, 120 mL/L of water and 200 mL/L of water as well as a comparison treatment, control (untreated) and the provision of urea fertilizer 3,3 g/plant. The results showed that the utilization some kinds of cattle urine provides a good effect on plant growth, which is reflected from the dry weight of the plant. Treatment goat's urine concentration 40 mL/L of water and 120 mL/L of water tends to affect on the dry weight shoot, dry weight root, and shoot root ratio on seedling oil palm.

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.

Asbur, Y. dan M. Ariyanti: Peran konservasi tanah terhadap cadangan karbon tanah, bahan organik, dan pertumbuhan kelapa sawit (Elaeis guineensis jacq.) Asbur, Y. • M. AriyantiPeran konservasi tanah terhadap cadangan karbon tanah, bahan organik, dan pertumbuhan kelapa sawit (Elaeis guineensis jacq.)The role of soil conservation to soil carbon stocks, organic matter, and oil palm (Elaeis guineensis jacq.) Growth Abstract Two methods for Soil conservation in oil palm plantations are by vegetatively and mechanically. Vegetatively method is generally using plants that grow at oil palm plantation such as Asystasia gangetica and Nephrolepis biserrata as cover crop, while mechanically is develop the ridge terrace by cutting the slope. This research aims to determine the role of soil conservation on soil carbon stock, organic matter, and oil palm growth. The research was conducted in mature oil palm plantation (planted year 2005), PTPN VII, South Lampung from August, 2014 until Aprl, 2015.The research used nested design with 6 repetitions nested in each treatment. The treatment consists of a ridge terrace (without and with ridge terrace), and cover crop (without and with cover crop N.biserrata, andA.gangetica). The results showed that the soil conservation application using cover crop and ridge terrace increased carbon stock and soil organic matter compared without soil conservation, respectively of 4.44 t/ha and 0.69% (N.biserrata without ridge terrace); 5.28 t/ha and 0.83% (A.gangetica without ridge terrace); 7.04 t/ha and 1.10% (ridge terrace without cover crop); 10.45 t/ha and 1.64% (N.biserrata with ridge terrace); 11.33 t/ha and 1.78% (A.gangetica without ridge terrace). Soil conservation application also affects the growth of oil palm, especially the average of rachis length and the number of broken leaves.

The existence of oil palm plantations as a possible cause of drought in the surrounding areas in Indonesia is a critical issue. Therefore, information related to the effects of oil palm plantations on the surrounding environment in terms of soil water content (SWC) availability is needed. Soil and water conservation techniques in the form  of ridge terracing and cover crops,  such as Nephrolepis biserrata,  can be  expected to potentially improve soil water  reserves, especially in the dry-season, by accumulating water  in the rainy season.  This study aimed to study the effects of N. biserrata as cover crop, together with the potential effects of ridge terraces, on the water balance in mature oil palm plantations.  The research was conducted in mature oil palm plantations, Afdeling III block 375 (planted in 1996) and block 415 (planted in 2005), Rejosari Unit, PT Perkebunan Nusantara (PTPN) VII in Natar District, South Lampung Regency, Indonesia, from August 2014 to January 2015. The research was based on of setting up 15 m x 20 m experimental plots with the following treatments:  (i) without ridge terraces and without N. biserrata (G0T0); (ii) without ridge terraces but with N. biserrata (G0T1); (iii) with ridge terraces but without N. biserrata (G1T0); (iv) with ridge terraces and with N. biserrata (G1T1).   Hydrology parameter data were collected for each treatment plot; water balance was calculated using a water balance equation. The results showed that the use of the cover crop N. biserrata in combination with ridge terraces helped improving SWC reserves by approximately 71% and 12%, respectively.  The use of N. biserrata as a cover crop reduced the rate of water loss by percolation and run-off, by approximately 36% and 80%, respectively, in an area where the annual rainfall is above 2,400 mm per year.  The presence of N. biserrata shortened the period of SWC deficit by extending the period of a water surplus by 70 days when compared with ridge terracing alone (which reduced the period of SWC by 50 days).

The growth response of oil palm (Elaeis Guineensis Jacq.) seedling toward the application of organic fertilizer from palm fronds and NPK compound fertilizerThe research was aimed to study the influence between organic fertilizers from palm fronds and NPK compound fertilizer to reduce NPK compound fertilizer in main nursery. The experiment was conducted from January to April 2017 at the Experiment Station Ciparanje, Faculty of Agriculture, Universitas Padjadjaran. The experimental design used was Randomized Block Design that arranged in factorial patterns with two factors and three replications. The fisrt factor was dosage of organic fertilizers from palm fronds consisted of three levels of 0 g/polybag, 800 g/polybag, and 1600 g/polybag and the second factor was dosage of NPK compound fertilizer consisted of four levels of 0 g/polybag, 20 g/polybag, 40 g/polybag, and 60 g/polybag. The result of the experiment showed that there was interaction effect between organic fertilizers from palm fronds and NPK compound fertilizer on height of seedling and dry weight of the shoot. The dosage of 1600 g/polybag organic fertilizers from palm fronds with the dosage of 20 g/polybag NPK compound fertilizer showed the best result in dry weight of the shoot.Keywords: Oil palm seedling, Main nursery, Organic fertilizer, Palm frond, NPK compound fertilizerABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh interaksi antara pupuk organik asal pelepah kelapa sawit dengan pupuk majemuk NPK yang baik untuk mengurangi penggunaan pupuk majemuk NPK di pembibitan utama kelapa sawit. Percobaan dilaksanakan dari bulan Januari sampai dengan April 2017 di Kebun Percobaan Ciparanje, Fakultas , Universitas Padjadjaran. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok dengan pola faktorial yang diulang sebanyak tiga kali. Faktor pertama meliputi dosis pupuk organik asal pelepah kelapa sawit terdiri dari tiga taraf yaitu 0 g/polybag, 800 g/polybag, dan 1600 g/polybag dan faktor kedua dosis pupuk majemuk NPK yang terdiri empat taraf yaitu 0 g/polybag, 20 g/polybag, 40 g/polybag, dan 60 g/polybag. Hasil percobaan menunjukkan bahwa terdapat pengaruh interaksi pupuk organik asal pelepah kelapa sawit dengan pupuk majemuk NPK terhadap tinggi tanaman dan bobot kering tajuk. Perlakuan pupuk organik asal pelepah kelapa sawit 1600 g/bibit dengan pupuk majemuk NPK 20 g/bibit menghasilkan bobot kering tajuk bibit kelapa sawit terbaik.Kata Kunci: Bibit kelapa sawit, Pembibitan utama, Pupuk organik, Pelepah kelapa sawit, NPK