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.

Zingiber barbatum Wall. (family Zingiberaceae), is an underutilized medicinal plant and commonly known as 'Meik tha-lin' in Myanmar where it is used in the indigenous system of medicine. In the present study, 19 accessions of Z. barbatum from five provinces in Myanmar have been utilized to characterize and assess genetic diversity. Twenty-nine morphological characters were noted, including growth habit, leaf, pseudo-stem and rhizome characters. Fifteen primer sets of P450-based analogue (PBA) markers were used to reveal molecular characteristics. Of the 29 morphological characters, 22 showed a high degree of variation within wild ginger accessions, whereas 20 of these characters contributed significantly to morphological variation. Eleven amplified primer sets gave a total of 175 bands and exhibited 92.15% polymorphism across Z. barbatum accessions. Based on morphological characters and PBA markers, 19 accessions can be divided into two morphotype groups with comparatively higher genetic diversity. This information can be applied in future crop improvement, proper conservation and better use of this underutilized medicinal species.

Determination of grain yields of stable and high-yielding maize hybrids in a wide environment requires high accuracy. Many stability measurement methods have been used in multi-environment experiments. However, the relationships among the different methods are still difficult to understand. The objectives of this study were to 1. Identify the effect of growing season and location (Environments = E), hybrids (Genotypes = G), and their interactions (GEIs) on grain yields; 2. Select high-yielding and stable maize hybrids in a wide range of environments; 3. Determine the relationship between each stability estimation; and 4. Determine the mega-environment of maize hybrid and identify the best locations for testing. Field experiments were conducted at ten locations in Java Island, Indonesia, for two growing seasons using a randomized completed block design with three replications. The experimental results showed that the main effects of the growing season, location, hybrid, and GEIs, significantly affected maize hybrid yields. Stability estimations of TOP, S(3), S(6), NP(2), NP(3), KR, NP(4), CVi, and bi, belong to the concept of dynamic stability that can be used to select maize hybrids in favorable environments, while other estimations were classified as in the static stability. Three maize hybrids were successfully selected, with high and stable yields based on numerical and visual stability estimations, namely SC2, SC7, and SC9. The three hybrids can be used as candidates for sustainable maize development programs. The dry season, the rainy season, and the combination of two growing seasons produced three mega-environments. GJRS and KARS were the most discriminative environments. Both environments can be used as favorable environments for selecting the ideal maize hybrid.

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Bambara groundnut (Vigna subteranea L.) is one of underutliized crops in Indonesia. Bambara groundnut is potential to be developed and can be utilized as an alternative food source in Indonesia. Bambara groundnut greatly varies and has a very wide area of adaptation. The experiment was conducted at the experimental field station at Ciparanje in Padjadjaran University. Starting on September 2014 until March 2015 with Randomized Block Design (RBD) and repeated two times. The research used 30 accessions originally from various locations in West Java (Bandung, Tasikmalaya, Garut, Sumedang, Bogor, Majalengka) and East Java (Lamongan, Madura). Genetic variability of Bambara groundnut landrace  in some West Java showed broad criteria on the characters fresh pod weight, dry pod weight, weight of 100 seeds, and weight per plot. Genotypes which had many similarities in some characters based on euclidian distance coefficient had close relationship.

Improvement of high yield maize cultivars possessing high quality of seed as showed by high lysine and tryptophan content must be fulfilled with resistance against downy mildew pathogen in any maize breeding program. A set of experiment to study genetic variability and to estimate both heritability and heterosis of important characters of grain yield on DMR and QPM lines has been conducted. Four downy mildew resistance (DMR) lines, i.e. Nei 9008, P 345, Ki 3, and MR 10; three quality protein maize (QPM) lines, including CML 161, CML 163, and CML 172; and their single cross hybrids formed based on line × tester mating design were used in the experiment. The following characters: height of the first ear, seeds number per row, seed weight per ear, and grain yield per plot showed broad genetic variability. Narrow sense heritability (hns) of grain yield and its components ranged from 0.01 to 0.71. Broad sense heritability (hbs), on the other hand, ranged from 0.20 to 0.74. It was found that hybrid derived from crossing between parental inbred lines possessing broad genetic background would express high heterosis.

Heritabilitas, variabilitas, dan kekerabatan dari suatu populasi sangat penting dalam pera-kitan kultivar unggul pisang. Parameter genetik tersebut merupakan langkah awal dalam suatu kegiatan seleksi pada populasi pisang ambon ini. Tujuan dari penelitian ini adalah mengestimasi nilai hertitabilitas, variabilitas, dan hubungan kekerabatan 15 genotip pisang ambon. Adapun metode penelitian yang digunakan merupakan metode eksperimen dengan tata ruang Rancangan Acak Kelompok (RAK) dengan ulangan dua kali. Penelitian ini dilakukan di Kebun Percobaan Ciparanje, Unpad Jatinangor, dengan ketinggian 753 m di atas permukaan laut (dpl). Waktu penelitian dilaksanakan pada bulan Mei 2013 sampai dengan bulan Februari 2014. Hasil penelitian menunjukkan bahwa nilai heritabilitas pada semua karakter 15 genotip pisang ambon memiliki nilai yang rendah yang artinya bahwa lingkungan berpengaruh besar terhadap pertum-buhan dan perkembangan tanaman pisang, sedangkan pengaruh genetiknya kecil. Variabilitas genetik yang luas terlihat pada karakter lebar helai daun dan rhizoma (anakan). Sedangkan variabilitas genetik yang sempit terdapat pada karakter panjang petiole. Karakter lebar helai daun dan rhizoma (anakan) dapat mempermudah efektifnya program seleksi. Kemudian pada analisis kekerabatan genetik dari ke-15 genotip pisang ambon asal Jawa Barat, hanya genotip AB13 yang memiliki kekerabatan genetik yang jauh dari genotip lain, berdasarkan jarak koefisien Euclidian dalam karakter kualitatif.Kata kunci: Analisis kekerabatan genetik ∙ Heritabilitas ∙ Jawa Barat ∙ Pisang ambon ∙ variabilitas