Abstract:
Azolla is a nitrogen-fixing freshwater fern used as a bio-fertilizer and livestock feed.
Traditional cultivation with cow dung and topsoil at the pond bottom increases cow
dung mixing with the azolla harvest, reducing its animal feed quality. Hence, this
study explored alternative methods to enhance azolla quality, yield, and nutrients
while reducing cow dung mixing with the harvest. The research was conducted in a
randomized complete block design (RCBD) with three treatments, each replicated
three times. In treatment 1 (control), a mixture of topsoil and cow dung was placed
directly on the pond bottom at the recommended rate. Treatment 2 used compost to
replace half of the topsoil in the recommended mixture and applied directly to the
bottom, while Treatment 3 used the traditional, topsoil-cow dung mixture enclosed in
gunny bags placed at the pond bottom. Azolla growth, biomass yield, and protein
content were measured and analyzed using ANOVA at a 95% probability level. At
each harvest, samples were collected from half of the pond area (0.75 m²) for
measurement. Results indicated significant differences (p<0.05) in fresh and dry
biomass yields among the treatments. After seven harvests, the cumulative yields for
Treatment 1 were 4.28±0.59 kg (fresh weight) and 0.16±0.03 kg (dry weight), while
Treatment 3 yielded 4.68±0.18 kg (fresh weight) and 0.16±0.003 kg (dry weight).
Both treatments demonstrated higher biomass production compared to Treatment 2,
which exhibited significantly lower yields of 1.93±0.33 kg (fresh weight) and
0.08±0.01 kg (dry weight). There were no significant differences (p>0.05) across
treatments regarding leaf length (11.92±1.92 mm), branching (4.47±0.69), and
protein content (26.53±2.98%), suggesting that these attributes are unaffected by the
cultivation method. This study concludes that enclosing the topsoil-cow dung mixture
in gunny bags at the pond bottom improves azolla cultivation for quality animal feed.
