Banana production irrigated with treated effluent in the Canary Islands.

The Giant Cavendish variety of bananas was grown for two years under four different microirrigation (drip) water quality treatments. The treatments consisted of fresh groundwater (FW), fresh groundwater (70%) mixed with secondary effluent (30%) (FW+SE), desalinized secondary effluent (70%) mixed with secondary effluent (30%) (DSE+SE), and desalinized secondary effluent (DSE). The experimental design was a Randomized Complete Block (RCB) design with three replications and four treatments. The production was under greenhouse conditions, typical for the Gran Canaria, Canary Islands. Plants were grown following typical water and fertilizer application used by the best growers on the Island. Productivity of banana plants, estimated as mean bunch weight, was significantly affected by water quality. Plants irrigated exclusively with desalinated secondary effluent showed significantly lower yield than those irrigated using fresh water. Desalinized secondary effluent had most of the salts removed; however, this treatment had the highest levels of SAR. There was no significant difference in yield in the two higher salinity treatments and the 30% addition of secondary effluent did not negatively impact plant growth or banana yield as compared with the FW treatment.