Study on the effects of organic fertilizer solution and shading level on the growth of Azolla microphylla

Abstract

In the trend of sustainable agriculture, the use of agricultural by-products to replace chemical fertilizers is increasingly focused. Azolla sp. is a green manure source which is rich of protein, minerals and able to fix symbiotic nitrogen that contributes to cost reduction and soil’s quality improvement. This study evaluated the effect of organic solutions derived from fish’s by-products, cow dung and Azolla, combining effect of different shaded ranges on the growth of Azolla microphylla. The experiment were arranged in a completely random block design (RCBD) using styrofoam boxes (32 × 45 × 20) cm with 10 cm depth of water, adding with 5 g of Azolla microphylla each box. Results showed that the 50-fold diluted organic solution derived from fish’s by-products promoted the best growth of Azolla microphylla. 40 % of shade was confirmed suitable for Azolla microphylla growth after 7 days, leaves’ horizontal length reached 12.3 mm, fresh biomass per box reached 68.55 g, dry biomass per box reached 5.81 g, and dry matter reached 8.48 %. The research proved the potential applying of fish’s by-products in production of other crops, thereby promoting the circular economy in agriculture.