INDONESIAN JOURNAL OF AGRICULTURAL SCIENCE

47-54

Authors: A. Wihardjaka, S. Djalal Tandjung, B. Hendro Sunarminto, Eko Sugiharto

Rice cultivation is one of the antropogenic sources of nitrous oxide (N2O) emission that is produced by microbiological nitrification-denitrification processes. Incorporating soil amendment in rainfed rice soil attempted to increase soil productivity, while nematicide application aimed to maintain root growth system. Incorporating soil amendment and nematicide application are predicted to suppress N2O production in lowland rice. The objective of this research was to study the interaction of soil organic amendment and nematicide on N2O emission and nitrogen uptake from rainfed lowland rice soils. A field experiment was conducted in rainfed lowland rice soils during 2010/2011 wet season (direct seeded rice) and 2011 dry season (transplanted rice). The 3 x 3 factorial trial was arranged in a randomized completely block design with three replications. The first factor was soil amendment consisted of without rice straw, fresh rice straw and composted rice straw. The second factor was nematicide application consisted of without nematicide, neemcake and carbofuran. Variables measured were N2O flux, rice grain yield and nitrogen uptake. Incorporation of fresh and composted rice straws reduced N2O flux about 49.2% and 59.9% in transplanted rice, and 32.9% and 28.2% in direct seeded rice, respectively. The neemcake application reduced N2O emission about 44-50%, while carbofuran application decreased N2O emission by 23-35%. Neemcake has a good potential as nitrification inhibitor of N2O emission, so the neem trees have a prospect to be cultivated intensively. The reduction of N2O emission was effective in direct seeded rice system with the application of neemcake and fresh rice straw, however, in transplanted rice system it was effective with neemcake and composted rice straw applications.

63-70

Authors: Budi Tangendjaja

Dried distillers grains with solubles (DDGS) is a co-product of ethanol industry made from grains through fermentation process and it can be used for animal feeding especially for dairy cows. A feeding trial on US corn DDGS was conducted at commercial dairy farm in Vietnam during hot condition in 2010. One hundred and fifty six dairy cows in a later stage of milk production were allotted randomly in three groups of 52 cows with similar milk production. Three dietary treatments offered comprised control diet, diet with 7.5% DDGS and diet with 15% DDGS. The diets were formulated to contain similar nutrient profiles and comprised forages (corn, elephant grass and alfalfa hay), brewery waste, soybean curd waste, corn, soybean meal, molasses and commercial dairy supplement. The diet was manufactured locally in total mixed ration system and delivered two times per day. Milk production, feed consump-tion and milk quality were measured for 5 days before the trial and 45 days after the trial. The result demonstrated that feeding DDGS could support higher milk production without affecting feed consumption. Feeding DDGS at 7.5% and 15% resulted in higher milk production of 2 and 4 kg per day respectively compared to cows fed control diet. Feed intake remained unaffected at around 35 kg per day. Milk quality as measured by total solid and fat content was similar in cows fed the control diet and DDGS at 7.5%. Feeding DDGS at 15% tended to have slightly better total solid and fat content. Feeding DDGS was able to reduce cost of the diets; diet cost for control, DDGS 7.5% and DDGS 15% were VND 2537, 2460 and 2399 per kg, respectively. It is concluded that DDGS can be economically used for feeding dairy cows in hot climate condition and improving milk production.

79-86

Authors: Meynarti Sari Dewi Ibrahim, Rr. Sri Hartati, Rubiyo, Agus Purwito, Sudarsono

Propagation of Coffea arabica L. through direct and indirect somatic embryogenesis technique is promising for producing large number of coffee seedlings. The objectives of the research were to evaluate methods for direct and indirect somatic embryo-genesis induction of C. arabica var. Kartika. The explants were the youngest fully expanded leaves of arabica coffee. The evalu-ated medium was modified Murashige and Skoog (MS) medium supplemented with a combination of 2.26 µM 2,4-D + 4.54 or 9.08 µM thidiazuron; 4.52 µM 2,4-D + 4.54 or 9.08 µM thidiazuron; or 9.04 µM 2,4-D + 9.08 µM thidiazuron. Both calli (100 mg) and pre-embryos developed from the edge of leaf explants were subcultured into regeneration medium (half strength MS with modified vitamin, supplemented with kinetine 9.30 µM and adenine sulfate 40 mg L-1). The results showed coffee leaf explant cultured on medium containing 2.26 µM 2,4-D + 4.54 or 9.08 µM thidiazuron to induce direct somatic embriogenesis from explant, while that of 4.52 or 9.04 µM 2,4-D + 9.08 µM thidiazuron to induced indirect somatic embrio-genesis. The medium for calli induction from coffee by explants was medium supplemented with 4.52 or 9.04 µM 2,4-D in combination with 9.08 µM thidiazuron. On the other hand, the best medium for activation of induction of somatic embryos was MS medium supplemented with 9.04 µM 2,4-D + 9.08 µM thidiazuron. Based on this results, the first step for developing micropropagation for coffee has been resolved. The subsequent studies will be directed to evaluate agronomic performance of the derived planting materials.

1-6

Authors: Nesti F. Sianipar, Wilmar Maarisit, Alice Valencia

Rodent tuber (Typhonium flagelliforme Lodd.) is a medicinal plant particularly found in Java. The plant is used as an ingredient for conventional cancer treatment. The aim of this study was to determine the toxic activities of crude extracts and column chromatography fractions of rodent tuber on Artemia salina larvae. Rodent tuber plant was obtained from the Indonesian Spice and Medicinal Crops Research Institute in Bogor, West Java. The experiment was conducted in the Biology Laboratory of Universitas Pelita Harapan, Tangerang, Banten. Leaves and petioles of the plant were macerated with acetone and the filtrates were evaporated (40°C) to obtain crude extracts. The crude extracts were partitioned with ethyl acetate, followed with hexane, chloroform and butanol. Toxicity test of the extracts was performed using the Brine Shrimp Lethality Test (BSLT) method on A. salina larvae. Extract showing the most toxic was fractioned using column chromatography and then tested on the larvae. The experiment was designed in a completely randomized factorial, four replicates for crude extracts and two replicates for the fractions. Treatments were different types of extracts (hexane, chloroform and butanol) at various concentrations (500, 1,000 and 1,500 μg ml-1 of 5% Tween solution). Fractions of the column chromatography used were taken from the column number 1, 3 and 10, and tested their toxicities at 200, 400, 600, 800 and 1,000 μg ml-1 of 5% Tween solution. Parameters observed were the death of A. salina expressed as LC50. The study showed that hexane extract of the petioles had the most toxic to A. salina (LC50 = 762.08 μg ml-1). Fraction number 10 showed the highest toxic (LC50 = 381.07 μg ml-1), whereas the lowest was fraction number 3 (LC50 = 653.13 μg ml-1). The study indicates that rodent tuber plant from Bogor is toxic to A. salina and further test for its cytotoxic activity is justified.

15-26

Authors: Yudhistira Nugraha, Georgiana V. Vergara, David J. Mackill, Abdel Bagi Ismail

Two types of floods can be happen in rice crops, i.e. flash floods and stagnant floods. Flash floods cause complete submergence for up to 2 weeks, while stagnant floods (SF) could partially submerge part of rice plant. To overcome yield loss due to the floods, introgression of SUB1 gene, known as a gene suppressing cell elongation and carbohydrate metabolism, to rice genotype can increase plant tolerance to complete submergence for 10 days or more. The study aimed to evaluate the response of 18 rice genotypes, including the recently developed sixth pair SUB1 near isogenic lines (NILs) of mega-rice varieties (Swarna, Sambha Mahsuri, IR64, TDK1, BR11, and CR1009), to various flooding conditions. The rice genotypes were planted at field ponds at Los Banos, Philippines, in the wet season (WS) of 2009. The treatments were 15 days submergence, SF, SF follows submergence and normal conditions. Each treatment was arranged in completely randomized block design with three replications. The results showed that the SUB1 introgression rice lines had higher survival compared to the non-SUB1 and did not much elongate their shoots during submergence. Nevertheless, under SF the rice genotypes should elongates their shoots to allow restoring contact with the air. SF and SF follows submergence decreased the panicle number, grain number per panicle and panicle fertility. Consequently, the yield declined. It suggests that sensitive genotypes are mostly sourcelimited during grain filling. The SUB1 introgression lines had higher chlorophyll concentration and less depletion in soluble sugar and starch after submergence. Under SF, soluble sugar and starch contents between the SUB1 NILs and non-SUB1 lines were not significantly different. Introgression of the SUB1 into high-yielding varieties improved submergence tolerance without affecting yield potential. The study indicates that introgression of the SUB1 into taller type rice varieties should be done to compensate the effect of suppressed elongation.

36-43

Authors: U.D. Chavan, R. Amarowicz, F. Shahidi

Beach pea is mostly grown on seashores and it contains higher amount of protein than other legumes. However, the pea has several undesirable attributes, such as long cooking time and hard to germinate (imbibitions) that limited its use as food. The present investigation aimed to study the physico-chemical properties, cooking characteristics and hull crude fibre structure of beach pea as compare to other similar legumes. Standard methods of processing pulses were used for present study. Beach pea seeds contained very low grain weight, density, hydration capacity, hydration index, swelling capacity and swelling index than the green pea and field pea. Beach pea had higher amount of crude protein, ash, crude fibre and polyphenols, but lower in starch content than the green pea and field pea. Without any treatment to beach pea seeds the water uptake capacity was very low. Mechanical treatment to beach pea seeds increased the water uptake percentage. The recovery of hull was 3 to 6 times higher in beach pea than that of green pea and field pea. The crude protein content in beach pea hull was 2-5% higher than others. The beach pea hull, dhal and whole seeds were good source of macro- and micro- minerals than that of the other two peas. The electron microscopic structure of beach pea hull crude fibre showed a very close and compact structure than green pea and field pea hull crude fibre structure. Lowering the hardness of beach pea seeds with mechanical or chemical treatments will give more scope for their utilization in the human nutrition.