FIELD PERFORMANCE OF THE CAPILLARY WICK IRRIGATION (CAPILLARIGATION) SYSTEM FOR RICE-BASED CROPS

The Philippines is suffering from the devastating effect of climate change. During extreme drought periods when it is already too risky to plant rice, farmers are advised to plant vegetables and other short duration crops so as to maximize the use of limited water supply and have an alternate source of income. This study evaluated the field performance of a locally developed irrigation system designed to be as efficient as possible so as to maximize the use of the limited supply of water during such conditions and as low cost as possible so that smallholder farmers could afford to use it. The resulting prototype is a do-it-yourself type irrigation system which is almost similar in layout as that of the drip irrigation system, except that, among other things, it makes use of capillary wicks as drippers (hence called as capillarigation system) and maximizes the use of local and recycled materials. Results of field tests consistently showed that the capillarigation system outperformed the existing farmers’ irrigation practices (drip and hose) in terms of water productivity. In a field planted with green pepper (Capsicum annuum L.), the system yielded higher water productivity of 36.6 g/L as compared to the drip irrigation system (9.9 g/L). The same trend was observed when tested in another field planted with eggplants (Solanum melongena esculentum). Being able to work with unfiltered water, with very low operating pressure (15-20cm) and discharge rate (20-30mL/h), the capillarigation system offers advantages when compared with other existing irrigation methods. It however still needs more field tests so as to further evaluate its performance under various crop, field, soil, and water conditions.