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Pot experiment was conducted to observe the effect of frass (insect feces) from Black Soldier Fly larvae (BSFL) as soil amendments at different application rates in comparation with other organic fertilizers on Pakchoi (Brassica rapa L). The experimental design was completely random with seven treatments, namely compost, compost+LOB (liquid organic biofertilizer), 5%, 10%, and 15% BSF frass, chemical fertilizer (NPK, equivalent to 10 kg/ha), and soil as a control. After 35 days planting, the result showed that Pakchoi cultivated with compost+LOB, compost, and BSF frass produced the highest biomass compared to control and NPK treatment significantly. The highest total plant weight was achieved in the treatment of Compost+LOB (24.4 gr), followed by 10% BSF frass (23.3 gr), compost (21.8 gr), 15% BSF frass (20.7 gr), 5% BSF frass (19,8 gr), NPK (1.3 gr ) and control soil (0.9 gr). While the chlorophyll content was not significantly different between all treatments, the application of BSF frass tended to be higher but with curly leaf symptoms than other treatments. The population of P solubilizing bacteria and the activity of PME-ase enzyme in soil were also higher in the treatment of compost, compost+LOB, and BSF frass compared to control and NPK treatment.

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We investigated demographic, morphological and histological aspects of Distylaphis foliorum, a gall-forming nipponaphidine aphid from Java, Indonesia, whose first instar nymphs had been reported to have enlarged forelegs and attack other insects. The gall inhabitants of D. foliorum consisted of two discrete populations; one developing normally and the other remaining at the first instar. Morphometric analysis identified two types of first instar nymphs; nymphs with relatively long forelegs and slender abdomen, and nymphs with relatively short forelegs and fat abdomen. The former nymphs were found from both young galls and mature galls, while the latter nymphs were from young galls only. Histological analysis strongly suggested a reproductive division in the first instar. In the former nymphs from mature galls, ovaries and mycetomes were degenerate and replaced by well-developed fat body cells. These results indicated that D. foliorum has a morphologically differentiated sterile soldier caste in the first instar. This study is the first report of a soldier caste with morphological and reproductive division in the aphid tribe Nipponaphidini, and suggests that highly specialized soldier castes have evolved at least four times in aphids.

Cacao (Theobrama cacao) is one of the main plantation commodities in Indonesia which has an important role for the national economy. The low productivity of cacao plants in Indonesia is due to the condition of old plants, pests and diseases attacks which affect the quality of the fruit and decrease the plant’s productivity. The objective of this study was to isolate and identify of endophytic bacteria from stem, flower, leaf and fruit of T. cacao by using 16S rRNA gene as genetic marker. Twenty seven endophytic bacterial isolates were collected from local plantation in Yogyakarta area.  From this study, 8 endophytic bacterial strains exhibited the higher PGP traits. The isolates produced Indole Acetic Acid level by 0.3 to 5.21 ppm/hour. All of isolates had nitrogen fixation activity but have not phosphate solubilization activity. Among them, isolates CSDT 4 and CGKBH 4 showed promising potential as PGP bacteria. Based on the 16S rRNA gene sequences, those bacterial strains were identified as Brevibacillus brevis (CSDT 4) and Pantoea sp. (CGKBH 4). We propose that the B. brevis and Pantoea sp. which is reported for the first time for their PGP potential in cacao, exerts its beneficial effects on cacao crop through combined of activities. The potential PGP bacteria from the Cacao plant was used to make a specific bio-fertilizer formula for the Cacao plant, because of the different needs and condition that every plant requires.

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In fi eld experiments during dry season 2010, the effects of biofertilization on growth of fruit yield Semangka (Citrullus lanatus) and of biochemical properties of soil were investigated. The experimental design was Randomly Block Design (RBD) with four treatments and fi ve replications. The treatments were biofertilizer only; chemical fertilizer only; biofertilizer plus a half dose of chemical fertilizer, and control. The application of biofertilizer which was a mixture of Pseudomonas sp., Bacillus sp. and Streptomyces sp and chemical fertilizers (only 50% of the recommended dosage of NPK) increased vegetative growth (plant height, number of branches) compared to chemical fertilizer treatments only. An addition of biofertilizer with the chemical fertilizer also increased the biochemical properties as well as the yield of C. lanatus compared to other treatments. The possible role of biofertilizer on improving soil enzymatic activities, vegetative growths and yield will be discussed more detail in the paper.