This article summarizes the findings of scientific research on biological reduction of the mineralization of collector-arid water of the Bukhara region in the conditions of water deficit. Here, the Lemna minor mineralization can reduce the drainage capacity of 3-5 g/l by 22% on dry matter and 28% in chlorine ion. Dehydration by direct water with direct water the Bukhara-6 cotton harvest yielded an additional 4,2 ts/ha of cropland in the irrigated field, which was biologically degraded.