INDONESIAN JOURNAL OF AGRICULTURAL SCIENCE

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.