Combining Ability of Several Introduced and Local Chilli Pepper (Capsicum Annuum L.) Genotypes and Heterosis of the Offsprings

The objective of the study was to identify the combining ability of several introduced and local chilli genotypes and heterosis effects of their offsprings, as a result of the hybridisation process. This information will be used for production of hybrid varieties. The study was conducted from November 2006 to May 2007 at Tajur experimental station, Bogor, West Java, Indonesia. The fi ve parents with their ten F1 hybrids were evaluated in a randomized complete block design (RCBD) with three replications. The results showed that hybrid IPB C15 x IPB C19 had the highest fruit weight per plant, and hybrid IPB C8 x IPB C19 had the highest heterosis for this character. Hybrid IPB C8 x IPB C15 has highest number of fruits per plant and showed heterosis effects. Crosses among introduced and local genotypes resulted a high heterosis values. Additive variance of weight and number of fruits per plant were greater than the dominant variance. IPB C19 had the best general combining ability for fruit weight per plant character

Analisis Stabilitas Hasil Gabah Galur-galur Padi Melalui Pendekatan Parametrik Dan Nonparametrik

The failure of a genotype to perform relatively the same in different environments is defined as the interaction Genotype x Environment (G x E interaction). The existence of G x E is often causing breeders facing difficulty to select superior genotypes to be tested further. Efforts to quantify the interaction between the average yields of genotype with environment can be done by parametric and nonparametric approaches. Experiments were conducted at 16 sites in dry season of 2008 and 2009. A total of 14 rice genotypes were tested using randomized complete block design. Combined analyses of variances of 16 sites showed highly significant effects of locations, genotypes, and genotypes x locations. Parametric stability analysis using the coefficient of variability (CVi) showed 6 lines (BP1808-1F-25, BP1352-1G-KN, IR76510-24-3, BP1178-2F-26, OM 5240, OM 1490) were stable. Based on parametric analysis of variance stability (Sv), however only 3 lines namely BP1808-1F-25, S4616-PN-7-3, and IR76510-24-3 were stable. Cultivar superiority method of parametric stability showed that BP1808-1F-25, OM 5240 and OM 1490 were stable, while OM4495 was stable based on Nassar and Huehn nonparametric methods. Results of Spearman's correlation analysis showed that between CVi and Sv, and CVi and Pi were significantly correlated with r = 0.556, and r = 0.560, respectively. It indicated that those three stability parameters had equal strength for determining the stability of the lines or cultivars tested. Based on the three stability approaches BP1808-1F-25 was considered as stable line, while check cultivar Dodokan was unstable. Parametric stability was found more accurate than nonparametric ones, when assumption of the data distribution was fulfilled

Interaksi Genotipe X Lingkungan Untuk Hasil Gabah Padi Sawah

Grain yield of rice is determined by genotype (G), environment (E), and interaction between genotype x environment (G x E). Variety can achieve its maximum yield potential if it is grown in suitable environments. This study was aimed to determine the adaptability and the yield stability of rice genotypes grown in different environments. Sixteen rice genotypes were tested using RBD in 16 sites during the wet season of 2010/2011, and dry season of 2011. The tested rice lines were developed for resistance to pest and diseases. The experiment unit was 4 m x 5 m of plot, plants were fertilized with urea, SP36, and KCl at rates of 250 kg/ha, 100 kg/ha, and 100 kg/ha, respectively. Variable observed was grain yield per plot. Combined analyses of variance showed that there was no lines yielded higher than did check variety Conde. The AMMI analysis showed that the largest variation was contributed by the environment factors (76.49%), genotype x environment interactions (17.55%), and the smallest was contributed by the genotypes (5.97%). Data exploration using boxplot method indicated that the low contribution of the genotype x environment interaction variance in this study was due to the high degree of similarity of yield potentials among the genotypes, and due to high similarity of environmental conditions of the sites.Based on the analysis of AMMI 2, lines B12743 - MR-18-2-3-8, IPB107-F-82-2-1, and Conde was each classified as widely adapted genotypes, while G8, IPB107-F-27-6-1, and BIO111-2-BC-PIR-3714, each was considered as genotype having a specific adaptation