Morphological Characteristics of Paddy Earthworm in Heirloom Rice Farms in Upper Kalinga Province
DOI:
https://doi.org/10.65141/jeraff.v6i1.n8Keywords:
Paddy earthworm, Sparganophilus species, morphometric analysis, heirloom rice farms, taxonomyAbstract
This comparative observational study examined the morphological characteristics of paddy earthworms collected from heirloom rice farms in Tanudan, Tinglayan, and Balbalan in Kalinga Province, Philippines. A total of 90 specimens were collected and analyzed. Each station was treated as a replicate, and the average values per station were used for the statistical analysis. The traits measured were the body length, the body diameter, and the number of annuli. Other features like the setal arrangement, body shape, coloration, and prostomium type were also observed using microscopes. The results showed that the body length ranged from 75.03 mm to 81.59 mm, while the body diameter ranged from 1.13 mm to 1.18 mm. There was no significant difference in the body length (p = 0.0565) and body diameter (p = 0.6211) among the three locations. However, the number of annuli showed a significant difference (p = 0.0068), with Study Site 2 having the highest values. All specimens have four pairs of closely paired setae per segment (eight setae per segment) and a zygolobous prostomium, which supports their identification under the genus Sparganophilus. These traits were consistent across all sites. The presence of paddy earthworms suggests their role in soil processes such as decomposition and soil mixing in rice fields. However, their actual impact on rice plants was not directly measured in this study, which could be studied further. Thus, this study provides baseline information about paddy earthworms in Kalinga heirloom rice farms. It also suggests the need for future studies about the inclusion of molecular analysis and soil testing to better understand these organisms and their environment.
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