Floating culture system (FCS) is the only feasible way for crop cultivation during high and prolonged flooding period at riparian wetlands. Objective of this research was to evaluate growth and yield of chili pepper cultivated using three different FCS during high flooding period at tropical riparian wetland. Floating rafts were constructed using used plastic bottles. Dimension of the raft was 2m x 1m with load capacity of 60 kg m-2 ; therefore each raft can carry 120 kg dead weight of growing media and chili pepper grown on it. Chili pepper used was CK9856 variety. Three FCS treatments applied were: P 1 , with gunny sack layer placed at interface between water surface and growing media; P 2 , without gunny sack at the interface; and P 3 , bottom part of growing media was immersed in water at 2-3 cm depth. These treatments were compared to P 0 , conventionally cultivated chili pepper as control. Result of this study revealed that chili pepper cultivated using FCS (P 1 , P 2 , and P 3) significantly outperformed those of conventionally cultivated (P 0) as indicated by higher growth and yield. Among FCS treatments, P 2 produced the highest marketable yield (248.9 g plant-1). Therefore, the P 2 is recommended for cultivation of chili pepper by smallholder farmers at riparian wetlands during high and prolonged flooding period.

Rice growing season at riparian wetlands in Indonesia is started at the end of rainy season before floodwater completely subsides. However, available materials for nursery substrate are limited during flooding period of the wetlands. This study aimed to evaluate three available and affordable substrates for producing high quality rice seedlings. The three substrates evaluated were decaying biomass of Utricularia vulgaris (DBUv); mixed of soil and U. vulgaris biomass plus biochar (SUv+B); and soil amended with biochar (S+B). Rice seedling preparation was done using modified floating seedbeds, adjusted specifically for light weight load of the evaluated substrates. Results of this study indicated that seedlings sown on DBUv substrate were significantly taller than those on S+B or DBUv substrate at 21 DAS. Roots of seedlings sown on DBUv substrate exhibited minimum broken root tips, when they were pulled off the substrate, while more broken root tips were observed in those sown on SUv+B and S+B substrates, causing significantly more shorter intact roots. Broken root tip was closely related to substrate porosity. DBUv substrate had significantly higher porosity than SUv+B and S+B substrates. There were no significant differences in number of leaves and chlorophyll concentration index (CCI) among seedlings grown on all substrates. Better performance of seedlings grown on DBUv substrate was more pronounced on 21-day-old seedlings; therefore, it is recommended to farmers to use DBUv substrate and do transplanting of rice seedlings to paddy field at age of 21-day-old.

This research has been conducted on January until February 2015 at Agrostologi laboratory, industrial feed and soil science laboratory, in State Islamic University Sultan Syarif Kasim Riau. The purposed of the research was to determine the effect of bunch ash, boiler ash, and palm oil sludge with different doses of the red-yellow podsolic fertility. The research used random sampling method that consist of (1). Red-yellow podzolic soil with a bunch ash as much as 5 ton/ha (25 g), 10 ton/ha (50 g), 15 ton/ha (75 g). (2). Red-yellow podzolic soil with boiler ash as much as 5 ton/ha (25 g), 10 ton/ha (75 g), 15 ton/ha (75 g). (3). Red-yellow podzolic soil with sludge as much as 5 ton/ha (25 g), 10 ton/ha (50 g), 15 ton/ha (75 g). Total of treatment were 20 pollybag. Parameters observation consist of value pH H2O, N, P, K. The results showed that bunch ash doses of 15 ton/ha was the best material to improvement of soil chemical properties red-yellow podzolic (pH H2O, P and K), subsequently followed by boiler ash, but a decline N of giving bunch ash and boiler ash while sludge doses 15 ton/ha is the best material to improvement of soil chemical properties N.