Indonesian Journal of Agricultural Science
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CONTRIBUTION TO THE PHYLOGENY OF THE PANGASIIDAE BASED ON MITOCHONDRIAL 12S RDNA
Get PDFCatfishes are generally one of the economically important groups of fresh and brackish water fishes in the world. In many countries, they form a significant part of inland fisheries, and several species have been introduced in fish culture. Judging from literature, the main constraint to cultivate wild species and to optimise the production of pangasiid catfishes is due to the poorly documented systematics of this family. In the present contribution, the phylogenetic relationships within Pangasiidae are studied to contribute to a better insight in their taxonomy and evolution. The genetic relatedness is inferred using mitochondrial 12S rDNA gene sequences. To resolve the phylogenetic position of Laides in this group of catfish, five genera of Asian and African Schilbeidae are also considered. The results showed that a species group (complex) could be clearly seen in the genetic tree. Pangasius is more derive than the other genera. By using approximate molecular clock/evolutionary calibration from mitochondrial gene, a new episode of speciation for the family marked explosive radiation about 5- 8 million years ago (mya). This adaptive radiation extended until the Late Pleistocene. Regarding the relationships between the Pangasiidae and Schilbeidae, two families show an allopatric distribution with slight overlap. The Pangasiidae occur mainly in Southeast Asia, while the Schilbeidae are seen mainly on the Indian subcontinent (including Myanmar) and Africa. It confirms the separation between Schilbeidae and Pangasiidae occurred in the Early Miocene
SOYBEAN SEEDLING ROOT GROWTH PROMOTION BY 1-AMINOCYCLOPROPANE-1-CARBOXYLATE DEAMINASE-PRODUCING PSEUDOMONADS
Get PDFPseudomonad producing 1-aminocyclopropane-1-carboxylate (ACC) deaminase (E.C.4.1.99.4) has been known to promote plant growth by lowering ethylene biosynthesis in higher plants, which can be induced by indole-3-acetic acid (IAA) production. The objective of this study was to examine the ability of IAAproducing Pseudomonas isolated from local soil environment (rhizosphere of soybean grown in Plumbon's agricultural areain Cirebon, West Java, Indonesia) to promote soybean root growth in relation to their ACC deaminase activities. The experiments were conducted in growth room and Laboratory of Soil Biology Research, Indonesian Soil Research Institute, Bogor, from January to August 2008. Soybean seeds were inoculated by immersing the seeds for 1 hour in bacterial cell suspension containing approximately 108-109 cells ml-1. The seeds were then germinatedfor 2 days before planting in growth pouches containing sterilized distilled water. All treated and untreated seeds were grown for 7 days in growth room at 24°C with 1300 lux of light intensity for 12-hour followed by a 12-hour dark period at 22°C. ACC deaminase activity of the isolates was assayed based on their ability to grow in Dworkin-Foster’s salt minimal medium containing ammonium sulfate or ACC as a source of nitrogen. Thirteen out of 81 isolates tested significantly increased soybean root length and weight, up to 50% from untreated plants. Of 13 isolates, 11 demonstrated ACC deaminase activities. Two isolates that did not show ACC deaminase activities had lower capacity to produce IAA. The results suggest that the effectiveness of IAA producing Pseudomonas in promoting the growth of the soybean seedlings is associated with their ACC deaminase activities or they produce IAA at low levels
PROPERTIES AND MANAGEMENT IMPLICATIONS OF SOILS FORMED FROM VOLCANIC MATERIALS IN LEMBANG AREA, WEST JAVA
Get PDFSoils formed from volcanic materials have a high potential for agricultural development, especially for horticultural crops, tea, and pine trees. Data on the characteristics of these soils are important for the management planning. Six representative soil profiles developed on andesitic volcanic ash and tuff in Lembang area, West Java were studied to determine the soil physical, chemical, and mineralogical properties, to study the relationship between the soil properties, and to classify the soils according to the Soil Taxonomy. The results indicated that all the soils had very deep (>150 cm) solum. In general, the volcanic ash soils were darker colored, more granular, more friable, less sticky and less plastic than the volcanic tuff soils. Physically, the ash soils had lower bulk density (0.44-0.73 mg m-3) and higher available water content (13-33%) than the tuff soils. Bulk density decreased with increasing allophane. Chemically, the ash soils had higher pHNaF (mostly > 10), higher organic carbon (4.3-6.8% in upper horizons), higher CEC (20- 44 cmolc kg-1), and higher P retention (> 85%) than the tuff soils. P retention logarithmically increased with increasing oxalate extractable Al and allophane. The sand fractions of the ash soils were dominated by hornblende, while the tuff soils were predominantly composed of opaque minerals. In the clay fractions, the ash soils were dominated by allophane, whereas the tuff soils showed high contents of gibbsite and metahalloysite. Soils developed on volcanic ash were classified as Thaptic Hapludands and Typic Melanudands, while soils formed from volcanic tuff were classified as Andic Dystrudepts. The low bulk density and friable consistency of the soils contributed to favorable soil tilth. However, high P retention and Al saturation in most soils are limiting factors for plant growth. Application of P fertilizers and liming coupled with efficient placement can be recommended to enhance P availability and reduce Al toxicity. Organic matter can be used to reduce Al toxicity. Soil conservation needs to be considered, especially in the steep slope areas
APPLICATION OF FRUIT BAGGING, SANITATION, AND YELLOW STICKY TRAP TO CONTROL THRIPS ON MANGOSTEEN
Get PDFScars on mangosteen fruits caused by thrips are the most prominent constraint in Indonesian export of mangosteen. Most of the exported mangosteen are rejected due to scar appearance. This research aimed to study the effects of fruit bagging, sanitation, and sticky trap application on the scar intensity on mangosteen. The research was conducted at a farmer's polycultured mangosteen orchard in Lima Puluh Kota, West Sumatra, Indonesia from September 2006 to February 2007. The mangosteen trees were cultured with cacao and coconut. To study the effects of bagging on the number of scars, the fruits were individually bagged at different time points starting from the time of calyx falling down (0) followed at 2, 4, 6, 8, 10, 12, and 14 weeks later. Each treatment was replicated six times. The experiment of sanitation (SNT) and yellow fluorescent sticky trap (YST) application was designed in a completely randomized design with six replications, except for the control which was replicated only three times. Four treatments studied were SNT, YST, combination of SNT+YST, and control. The sanitation was applied by removing all weeds under the canopy of mangosteen trees followed with soil tillage and fogging. The sticky trap was nailed on woody sticks and placed on 3 m above the ground at four different positions around the tree canopy. Parameters observed were the percentage and intensityof scars and number of thrips caught on the sticky traps. The results showed that application of early bagging, SNT, YST, and SNT+YST were effective to reduce intensity and percentage of scars. However, combination of SNT+YST demonstrated the best results in reducing the intensity and percentage of scars by 32.14% and 42.82%, respectively. Combination of SNT+YST also drastically decreased thrips population as indicated by thelow number of thrips catched after five biweekly observations. Since the fifth observation, the thrips population was low (less than 5 thrips catched per sticky trap) and far below the economic threshold. The present study implies the importance of early fruit bagging, sanitation, and sticky trap application in protecting mangosteen fruits from scars
ESTIMATING SOYBEAN PRODUCTION EFFICIENCY IN IRRIGATED AREA OF BRANTAS RIVER BASIN
Get PDFSoybean has an important role in Indonesian diet, especially as source of protein, fat, mineral, and vitamin. Given the relatively stagnant technology, efficiency improvement at farm level would probably be an appropriate way to increase soybean production in the near future. The objective of this paper was to estimate the technical efficiency of soybean production in irrigated area of Brantas river basin and analyze factors affecting technical inefficiency level. The results indicated that the technical efficiency of soybean production in the sites was around 83%. The analysis, however, failed to identify the determinants of technical inefficiency because none of the parameters in the analysis was significant. Further study is required to identify the determinants such that the target groups of extension can be specifically determined. Since K2O fertilizer significantly affected soybean production while P2O5 and N fertilizers did not, the first step to improve the technical efficiency of soybean production was to provide soybean farmers with recommendation regarding balanced amount of fertilizers. The recommendation, however, should be derived from local verification trial in each site
THE INHERITANCE OF YIELD AND YIELD COMPONENTS OF FIVE WHEAT HYBRID POPULATIONS UNDER DROUGHT CONDITIONS
Get PDFThe magnitude of genetic inheritance and expected genetic advance are important for the prediction of response to selection in diverse environments and provide the basis for planning and evaluating breeding programs. This work investigated the inheritance of traits related to drought in wheat under natural drought conditions. Cross combinations were made to produce F1 and F2 hybrid populations, which were evaluated in a randomized completed block design with three replications at University of Agriculture, Faisalabad, Pakistan. Six wheat varieties/lines and six derived F2 hybrids were studied to ascertain heritability and genetic advance for plant height, days taken to maturity, number of tillers per plant, spike length, number of grains per spike, 1000-grain weight, and grain yield per plant. Data were collected and subjected to statistical genetic analyses. Heritability estimates and expected genetic advance for plant height, days taken to maturity, number of tillers per plant, 1000-grain weight and grain yield per plant were high for the entire cross combinations while the estimates for spike length and number of grains per spike were relatively low. Our results suggest that improvement for these characters should be faster because of higher heritabilities and greater phenotypic variation. Prospects of genetic improvement for all the characters studied are evident. The most promising cross combinations were WL60 × LU26S and WL61 × LU26S. These traits, therefore, deserve better attention in future breeding programs for evolving better wheat for stress environments.
VARIABILITY AND CORRELATION OF AGRONOMIC CHARACTERS OF MUNGBEAN GERMPLASM AND THEIR UTILIZATION FOR VARIETY IMPROVEMENT PROGRAM Lukman Hakim
Get PDFInformation on the variability and correlation between agronomic characters of mungbean accessions with their yield are important for supporting breeding program of the plant. A total of 350 mungbean accessions were evaluated at Muara Experimental Farm, Indonesian Center for Food Crops Research and Development, Bogor, during the dry season of 2005. The experiment was conducted in a completely randomized block design with three replications. Each accession was planted in two rows of 5 m long. Plant spacing was 40 cm x 20 cm, two plants per hill. Correlation and path coefficient analyses were used to quantifythe magnitude of the relationship between yield components and grain yield. The variability among the accessions was significant for most of the characters studied, especially for days to maturity, plant height, pods per plant, and seed size. Among the yield components, the number of pods per plant and plant height positively correlated with the grain yield, but theseed size negatively correlated with grain yield. The direct effects of the number of pods per plant and plant height on seed yield as indicated by path coefficient were the highest, while other causal effects were small or negative. Yield variation (1- R2) attributable to the nine yield component variables was slightly high (61.23%), which means that mungbean accessions with high grain yield should have sufficient plant height and high number of pods per plant. Therefore, these parameters (number of pods per plant and plant height) can be used as the selection criteria in mungbean breeding program. These criteria can be visualized during bulk selection on the early generation stage of F2 to F4, and subsequently on line development of individual plant (pedigree) of F5
EVALUATION OF NATURAL ENEMIES IN CONTROLLING OF THE BANANA WEEVIL BORER Cosmopolites sordidus Germar IN WEST SUMATRA
Get PDFThe banana weevil, Cosmopolites sordidus Germar, is an important pest of highland banana and plantain in Africa, but it exists in low densities in presumed area of origin in Southeast Asia such as in Indonesia. This suggests a possible existence of effective co-evolved natural enemies in the origin area of Indonesia, especially West Sumatra. The objectives of this study were: (1) to evaluate banana weevil pest status at selected sites in West Sumatra, (2) to survey parasitoids and predators, and (3) to determine the control potential of the most important natural enemies. Surveys were undertaken in March 2002-August 2003 in five locations in West Sumatra, i.e., Bukittinggi, Sitiung, Pariaman, Pasaman, and Batusangkar. Five farms per site were selected randomly among all farms that contained banana stands of > 0.5 ha. Sampling for banana weevil adults and damage, and for predators was done throughout small banana stands and within a 20 m x 40 m (0.08 ha) subplot on larger farms. Field-collected larvae were taken to the laboratory and reared on corm pieces (3 cm x 3 cm x 3 cm) until pupation. Larvae were collected from pseudostem as well as corm residues. To estimate the abundance of non-social predators, i.e., those other than ants, 10 residues each on each farm were examined from plants that had been harvested 1-4 weeks, 5-8 weeks or 9 or more weeks before our visit to the site. Samples of the different morphospecies were saved in alcohol for later identification. The result showed that the banana weevil incidence was found to be low, 0.6-1.7 adults per trap. Plant damage indices were below 2.2%. We collected and reared 24,360 eggs and 3118 larvae, but no parasitism was detected. Phorids (Megaselia sp.) and drosophilids were recovered from larval rearings, but most likely were scavengers. A complex of predators was detected, the most important of which was the histerid beetles, Plaesius javanus Erichson. In laboratory tests, adults and larvae of P. javanus attacked 75-88% and 38-53% of banana weevil larvae and pupae, respectively. Predatory ants, including species of Myrmicinae, Ponerinae, Formicinae, and Dolichoderinae, were found to be associated with banana plants and residues. Adults of Myopopone castanea Smith (Ponerinae) were directly observed attacking banana weevil larvae in crop residues. The adult banana weevil mortalities caused by the entomopathogen fungi of Beauveria bassiana from Baso, Sungaitarab, Sei Sariek, and Sikabau at highest density (3.2 x 108 spores ml-1) after two weeks were 96.67%, 90.00%, 60.00% and 83.33%, respectively. The high diversity of habitat conditions in which crop-pest-natural enemies systems exist, support the idea that banana weevil population and damage intensity in the study area is low due to active role of natural enemies
EVALUATION OF GENETIC DIVERSITY IN CACAO COLLECTED FROM KOLAKA, SOUTHEAST SULAWESI, USING SSR MARKERS
Get PDFKolaka, which is located in Southeast Sulawesi, has long been known as one of cacao production centers in Indonesia. Therefore, many different cacao germplasms can be found in this region. The study aimed to evaluate genetic diversity and relationships of 12 cacao genotypes collected from Kolaka. Genomic DNA was extracted by using a modified CTAB method. Meanwhile, genetic diversity was analyzed based on 16 SSR markers, which then separated by 6% non-denaturing polyacryl-amide gel electrophoresis. The result showed that all of those markers, 14 markers exhibited polymorphism and subsequently used for data analysis using NTSYS and PowerMarker program. About 70 different alleles were generated from 12 cacao genotypes analyzed with an average of 5 alleles per locus. Average value of polymorphism information content (PIC) resulted in this study was 0.59. The cluster analysis using UPGMA method based on the genetic similarity coefficient revealed that all cacao genotypes were separated into three major groups. The first group consisted of five cacao genotypes, the second one held four cacao genotypes, whereas the third group contained three genotypes. This result indicates that three genotypes that clustered separately from the others could be used as a good clonal candidate for cacao breeding program. The information resulted from this present study would be useful for future cacao breeding program, especially in efforts to release a new variety
THE TECHNICAL AND ECONOMICAL PERFORMANCE OF THE “ABC” TYPE PADDY DRYER
Get PDFFarmers in the villages always face the same problem of how to reduce the moisture content of paddy harvest during harvest and postharvest time, especially in wet season. At the farm level, the grain quality is poor and alternative drying using kerosene fuel is very costly. The objective of this research was to design and evaluate the technical and economical performance of drying paddy using an equipment known as "ABC" dryer. The dryer uses paddy husk as fuel. The research was conducted at Research Institute for Rice over three years (1993/94-1995/96). The result showed that the "ABC" type dryer could reduce the moisture content of 5 tons wet paddy from 22.25% to 15.03% in 9 hours or an average drying rate of 1.05% moisture content per hour, with drying cost of Rp 18kg-1. Reducing the moisture content further to 11.83% needed 16 hours or average drying rate 0.82% hour-1, with drying cost almost doubled (Rp 32 kg-1). These costs are far below that of kerosene drying, i.e., Rp 30 kg-1 and Rp 60 kg-1 to reach moisture content of 15.03% and 11.83%, respectively. Budget analysis showed that the B/C ratio were 1.57 and 1.84 and the IRR are above 41.26% and 47.42% to reach moisture contentsof 15.03% and 11.83%, respectively. The break even points of "ABC" dryer were 130 and 60 tons, respectively. The milling test showed that the milling rice from the "ABC" dryer had better recovery (milling rendement) and rice quality (head rice) was higher than that of from sun-drying