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The appropriate method of P fertilizer application is very important for the efficiency of P uptake and yield improvement. This research aimed to assess the growth response, seed product, and P uptake efficiency of soybean to the application of fast dissolved phosphorus fertilizer. Two consecutive potted experiments under greenhouse condition were conducted using Alfisols from Jumantono Karanganyar as planting media. The soybeans were planted and treated with six doses of P fertilizer. The treatments were designed in a completely randomized experiment with 5 replications. In the first experiment, the plants were harvested at the maximum vegetative growth for measurement of plant growth components and P uptake. In the second experiment, the plants were harvested at optimum grain maturity for seed yield and P efficiency measurements. The results showed that the application of fast dissolved-P fertilizer improved plant growth, seed yield and P uptake efficiency. Fast dissolved-P fertilizer was optimum at a dose of 100 kg/ha which was applied in a split application method at 0, 15, and 30 days after planting. However further field research is necessary to confirm the results. [ABSTRACT FROM AUTHOR]

Pruning is one of the techniques to improve plant growth and production. The aim of this research was to determine the effect of pruning on vegetative and generative growth, and fruit quality of 'Crystal' guava. The experiment was conducted from September 2016 to April 2017 at Cikabayan Research Station of Bogor Agricultural University, Dramaga, Bogor, Indonesia (-6.550780, 106.714531). The experiment used completely randomized design with six replications. There were three treatments i.e. a) pruning by leaving 4 pairs of leaves, b) pruning by leaving 8 pairs of leaves, and c) control (without pruning). Pruning was applied after shoot leaves grew fully. The result showed that pruning significantly increased the total number of shoots and generative shoots. Pruned plants produced more flower and fruit than un-pruned ones. Pruning by leaving 4 pairs of leaves tended to produce higher number of flower and fruit than those by leaving 8 pairs of leaves. Fruit weight and internal fruit quality were not affected by pruning. [ABSTRACT FROM AUTHOR]

Indonesia has number of accessions and cultivars of pummelo which are prospective to be developed. Pummelo contains higher antioxidants thus beneficial for health. This research aimed to get information of physical and chemical quality differences, antioxidant capacity, and explain the relationship between fruit quality and antioxidant capacity of selected seeded pummelo cultivars. Fruit was harvested in Banyuwangi and Magetan while fruit quality assesment was conducted in Laboratory of Agronomy and Horticulture Department, IPB. The results showed that physical qualities of fruit (weight loss, peel softness and peel color) and chemical qualities (total soluble solids and total titratable acidity) were changed during storage. Adas Nambangan and Banyuwangi cultivars have better physical and chemical qualities than other cultivars during storage until 10 weeks after harvest because of good visual appearance, the lowest decreased in weight loss and the good ratio of TSS:TTA. Seeded pummelo cultivars with dark red to reddish white fruit pulp had significant higher total phenolic, carotenoid, anthocyanin and antioxidant capacity than white fruit pulp. There were negative correlations between antioxidant capacity with colored pulp and total phenolic content. Banyuwangi had the highest antioxidant capacity in the pulp, followed by Bali Merah, Adas Nambangan, Pamelo Magetan, Srinyonya, Bali Putih cultivars. [ABSTRACT FROM AUTHOR]

The functional roles of Arbuscular Mycorrhiza (AM) in soils with P limitations are well documented. However, the protocol to produce effective AM inocula was still limited. This research aims at obtaining the effective AM culture in handling P constraints for maize growth on Andisols. The first experiment of pot culture I was to propagate and examine the effectiveness of AM isolates by using a factorial completely randomized design with two factors, A=media (A0: zeolite; A1: representative media=Andisol Tengaran; A2: typical media=a mixture of Andisol Tengaran+Tawangmangu; A3: typical media+Bio-RP nutrition; A4: Inceptisol) and I = AM inoculum source (I0: no inoculum; I1: AM from Andisol Tengaran; I2: AM from Andisol Tengaran + Tawangmangu; I3: AM from 8 soil types), with six replications. The second experiment investigated the consistency of mycorrhizal effectiveness by reculturing AM cultures generation I to pot cultures generation II with the same composition of the respective media. The combination treatments of A1I3, A2I2, A0I3, and A4I3 (AM cultures generation I), continued by A1I32, A2I22, A0I32, and A4I32 (AM cultures generation II) showed consistently the highest AM infectivity and effectiveness on maize growth and P uptake on Andisol-based media, and on the comparison media of zeolite and Inceptisol media, respectively. [ABSTRACT FROM AUTHOR]

Protoplast fusion is a useful technique for citrus genetic improvement. Establishment of protoplast technology could produce triploid seedles citrus and new citrus genetic combination. The aim of this research was to establish protoplast isolation, protoplast fusion between pummelo 'Nambangan' (Citrus maxima) and keprok 'Garut' (C. reticulata), and its protoplast culture. Protoplasts were isolated from leaves of in vitro seedlings of pummelo 'Nambangan' and embryogenic callus of keprok 'Garut' with two different compositions of enzymes. The results showed that optimum enzymes compositions for cells mesophyl wall degradation were consisted of 0.5 % Onozuka cellulase RS10, 0.5 % Macerozyme R10 and 0.1 % Pectolyase Y23. Optimum enzymes composition for callus embryogenic cells wall degradation were 0.5 % Onozuka cellulase RS10 added with 0.5 % Macerozyme R10. Protoplast fusion was conducted with PEG-mediated. Protoplast mixture were incubated in 40 % PEG for 8-10 min and after that could be observed 40.6 % of unfused protoplasts, 4.6 % of homofused mesophyl protoplasts, 28.2 % of homofused callus protoplasts, 7.8 % of heterofused and 9.6 % of multifused protoplasts from mesophyl and callus. Cells divided at the first week and began to form cell colonies afterwards in liquid culture. [ABSTRACT FROM AUTHOR]

The growth of entomopathogenic fungi Lecanicillium lecanii is strongly related to the media in increasing the fungi sporulation, enhancing its effectiveness in infecting target pests. This study aims to obtain L. lecanii propagation media with the highest conidia production, and the increased virulence on Cylas formicarius. The first stage of alternative media selection consists of: Potato Dextrose Agar; maize, rice; bran. The second stage of infectivity of the best alternative media consists of 5 treatments in 5 replications: synthetic insecticide (C+); distilled water (C-); 107 conidia/ml; 108 conidia/ml; 109 conidia/ml. The results show that the best colony growth rate is (1.15 mm) on Maize media, and the highest conidia density is (4.2 x 108 conidia/ml) on Maize media is not significantly different from PDA (1.3 x 108 conidia/ml). The best germination rate is (74.31%) on Maize media, and the highest media weight (1.10 g) on Rice media is not significantly different from maize (1.45 g). The infectivity of L.lecanii affect the mortality of C. formicarius (74%) substantially at a concentration of 109 conidia/ml. The LC50 value obtained is 2.6 x 107 conidia/ml. Thus, maize media can be an alternative medium for mass propagation of L. lecanii. [ABSTRACT FROM AUTHOR]