The purposes of this study were (1) to assess the effectiveness of drought tolerance indices for selection of drought tolerance in upland rice, and (2) to identify the most suitable drought tolerance indices to select for drought tolerant, high yielding upland rice genotypes. This study employed a Split Plot design consisting of irrigation levels as the main plots, and rice genotype as the sub-plot treatments. There were three main plots: 100% field capacity (FC); 75% FC; and 50% FC level. The subplot treatments consisted of 40 upland rice genotypes. Grain yields under no-stress and stressed conditions were used to calculate drought tolerance indices. There were significant variations in grain yields and drought tolerance indices between different rice genotype treatments. The indices from the literature found to be most suitable for the selection of drought tolerant upland rice cultivars were STI, GMP, MRP, HARM, REI, ATI, YI, SNPI. Ten genotypes from among the 40 tested-namely HK-07, ADN-04, PMK-01, ADN-05, NGR-022, ALR-02, HK-06, and KMD-01-were selected as combining drought tolerance with high yield potential.

Abstract. Firawati I, Murwantoko, Setyobudi E. 2017. Morphological and molecular characterization of hairtail (Trichiurus spp.) from Indian Ocean, southern coast of East Java,. The objective of this study was to identify species of hairtails (Trichiurus spp.) which caught from the southern coast of East Java, based on morphology and molecular characters. Three hundred and forty-nine fish samples were collected from two fishing port i.e. Muncar and Prigi. Twenty-two morphometric and four meristic characters were measured from each sample. The result showed that the hairtail samples consisted of two species, T. lepturus and T. brevis based on morphology characters. Based on Principal Component Analysis (PCA) and Discriminant Function Analysis (DFA), these species can be distinguished by the head and caudal character, which the length of an upper jaw and caudal peduncle characters were the main distinguish. Analysis of fragment (~600 bp) of the mitochondrial DNA encoding 16S rRNA gene showed that T. lepturus samples were 100% genetically identical with T. lepturus while T. brevis samples were 100% identical with T. brevis. Phylogenetic analysis showed that T. lepturus and T. brevis were distinct species while T. lepturus both which caught from Prigi and Muncar were closely related species. The molecular identification can be used to verify the result of morphological identification.

Blood disease in bananas caused by Ralstonia syzygii subsp. celebesensis is a bacterial wilt causing significant crop losses in Indonesia and Malaysia. Disease symptoms include wilting of the plant and red brown vascular staining, internal rot, and discoloration of green banana fruit. There is no known varietal resistance to this disease in the Musa genus, although variation in susceptibility has been observed, with the popular Indonesian cooking banana variety Kepok being highly susceptible. This study established the current geographic distribution of Blood disease in Indonesia and confirmed the pathogenicity of isolates by Koch's Postulates. The long-distance distribution of the disease followed an arbitrary pattern indicative of human-assisted movement of infected banana materials. In contrast, local or short distance spread radiated from a single infection source, indicative of dispersal by insects and possibly contaminated tools, water or soil. The rapid expansion of its geographical range makes Blood disease an emerging threat to banana production in Southeast Asia and beyond.

No abstract

Abstract. Mau YS, Ndiwa ASS, Markus JER, Arsa IGBA. 2019. Agronomic performance and drought tolerance level of sweet potato hybrids grown in Kupang, East Nusa Tenggara, Indonesia. Biodiversitas 20: 2187-2196. This study was conducted to evaluate agronomic performance and to assess drought tolerance level of purple and orange-fleshed F1 sweet potato hybrids in dryland during dry season in Kupang, East Nusa Tenggara. The study was carried out in Integrated Archipelagic Dryland Field Laboratory of Universitas Nusa Cendana, Kupang, from May to October 2018. Two sets of experiment were conducted, the first was for evaluation of agronomic performance, and the second was for evaluation of drought tolerance of the sweet potato genotypes. The first experiment assessed the agronomic performance of 20 sweet potato genotypes in a Randomized Block Design. The second experiment employed a Split Plot Design consisted of irrigation level as the main plot and sweet potato genotypes as subplot treatments. The main plot consisted of no stress (normal) and water-stressed conditions while the sub-plot comprised of 20 genotypes of the sweet potato. The observed agronomic performance variables included growth and yield parameters. Tuber yields in no stress and water-stressed conditions were observed and used for assessment of drought tolerance. The results showed that, in the agronomic performance experiment, the sweet potato genotypes differed significantly in all the observed agronomic performance variables including growth, yield contributing, and yield variables. UNC2016.Cil/JPV.01 and UNC2016.Cil/JPV.05 were short maturing genotypes with only about 90 days to harvesting while the rest of the genotypes were harvested in 120 to 150 days. The genotypes were also significantly varied in tuber yield; the highest was observed in UNC2016.JPV/KDL.11 (43.38 t ha-1). In the drought tolerance evaluation experiment, tuber yields in no stress and stressed condition were, respectively, 23.42 t ha-1 and 7.08 t ha-1. Six F1 hybrids were classified and selected as drought-tolerant genotypes with high yielding performance in both no stress and water-stressed conditions.