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We examined a new method to detect the biodiversity hotspots in terms of complex patch mosaics at a regional scale in East Java, Indonesia, in order to develop the safeguard against further expansion of monocultures by REDD+. A land-cover map consisting of five major land-cover types (forest, agricultural land, bare land, water, and residential) was generated with a 30 m x 30 m resolution by the unsupervised classification of a Landsat8-OLI image. Shannon’s diversity index ( H’ ) was calculated for each of 10.98 ha (11 x 11 pixels) landscape throughout the study area based on the dominance of the land-cover types by five calculation methods with different combinations of land-cover types. Then, the landscapes of upper 5 % in H’ was selected as the potential hotspots in terms of highly complex patch mosaics. Among the five potential hotspots, the calculation of H’ with four land-cover types (forest, agriculture, water, and bare land) was thought to be most suitable to set conservation targets at a regional scale, because the potential hotspots by this method showed aggregated distribution patterns, and was less sensitive to the small residential patches. While, no clear distribution trend was observed along the environmental gradients.

Recently, a new bacterial disease of maize (Zea mays) was observed in Kediri, East Java, Indonesia. Infected plants showed wilt symptoms occasionally accompanied by leaf blight. This study aims to characterize the causal agent of bacterial wilt and leaf blight of maize observed in Kediri. Gram-negative, facultative anaerobic bacteria were isolated from the diseased tissues. All bacterial strains (KD1A, KB2A, KD1, KD4, KB1) gave positive result both in the hypersensitive response and pathogen-nicity assays. However, only KD1 and KB1 strains could be re-isolated from the diseased tissues. Based on several physiological and biochemical assays, the bacteria resembled Pantoea agglomerans. Moreover, the strains showed negative result on PCR amplification using HRP1d and HRP3r, a primer pair specific for detection of P. stewartii subsp. stewartii. Analysis of 16S rRNA gene sequence of KD1 and KB1 showed highest homology at 88% and 90%, respectively to P. agglomerans strain DSM 3493 (NR 0419781). The homology values were too low to conclude that the bacteria were similar to P. agglomerans. These results suggest that bacterial pathogens isolated from maize in Kediri were strains of Pantoea sp.

The main objective of this research was to study the diversity of maize inbred lines based on phenotypic characters and SSR markers. The research, which was conducted from February to June 2011, was divided into field and laboratory research for molecular analysis. The molecular analysis was conducted at the Biotechnology Laboratory, Faculty of Agriculture, Brawijaya University Malang. The field trial was done in Kandat, Junrejo, Batu. Materials of the research were 35 genotypes of maize. Steps for molecular analysis included: (1) DNA isolation, (2) DNA-quality test, (3) PCR SSR, and (4) Visualization of the amplification result. The field trial was done by planting genotypes using a RCBD with 2 replications. Result of the dendogram analysis showed that 35 genotypes of maize were divided into 2 main clusters, A and B, that having 35% similarity level. Result for the analysis of variance showed significant difference among genotypes of maize on the entire of the observed phenotype characters. Heritability (H) ranged from 61.8% to 98.1%. Coefficient of variance ranged from 0.71 to 7.20%. Analysis on the genotypic correlation ranged from 0.06 to 1.0. Numbers of rows per ear showed significant correlation, in which Jaccard’s similarity coefficient (rs) = +0.43.

Low productivity of shallot in Indonesia can be improved through development of high yielding variety. The availability of genetic information related to the character being improved is inevitable for effective breeding program. In this study, seven shallot genotypes were evaluated for their combining ability for yield improvement using half diallel cross. Heterosis effect and heritability estimate was also investigated for yield-related characters. The results showed that there were significant differences in general combining ability (GCA) and specific combining ability (SCA) among the evaluated genotypes. Tiron and Timor had the greatest GCA. The greatest SCA and heterosis value was found in crosses of Kuning/Tiron, Timor/Bima Juna, Tiron/Timor and Kuning/Sibolangit. Heterosis effect varied from low to high. Broad sense heritability estimate for all characters was high, but narrow sense heritability was low for most charaters. The dominant gene action observed on all yield-related characters suggests that the evaluated genotypes are potential to be used in breeding for high yielding hybrid varieties. Keywords: GCA, SCA, heterosis, heritability, shallot