NEMATODE COMMUNITY ASSOCIATED WITH RECENTLY PLANTED BREADFRUIT, ARTOCARPUS ALTILIS, RHIZOSPHERE ON KAUA`I, HAWAI`I
Keywords: bacterivores, Cephalobus, fungivores, Helicotylenchus, herbivores, omnivores, predaceous, Rhabditidae
AbstractAlthough, breadfruit, Artocarpus altilis (Parkinson) Fosberg, is a traditional staple food crop in the Pacific Islands, the nematode community associated with a recently planted breadfruit rhizosphere is not well documented. A field at the Kaua`i Community College was therefore prepared and divided into 4 equal blocks, and 64 breadfruit saplings were planted in December 2014. Soil samples were taken from four blocks before breadfruit transplanting (year 0) and the rhizospheres of half of the plants of each block at 1, 2, and 3 years after breadfruit tree planting. Nematodes were extracted from the soil using the Baermann funnel technique and identified to genus. Frequency of occurrence (%) of each genus was determined. Each genus was grouped into a respective trophic group. Compared to year 0, 1, and 2, the greatest herbivores numbers were found in year 3 (P˂ 0.01). Pooled data of years 1, 2, and 3, nematode genera were observed including bacterivores, fungivores, omnivores, and predators (beneficial nematodes), and herbivores (40.0%, 17.77%, 15.55%, 15.55%, and 11.11%, respectively). Beneficial nematodes constituted 40 genera. The most frequent genus was Cephalobus (95.83% ± 02.76%) followed by other Rhabditidae (82.29% ± 04.54%). Helicotylenchus, Paratylenchus, Axonchium, Pratylenchus, and Xiphinema were observed in 71.88% ± 08.27%, 29.17% ±12.01%, 14.58% ± 06.34%, 05.21% ± 01.04% and 01.04% ± 01.04% soil samples, respectively. A positive relationship existed between the total herbivores number in breadfruit rhizosphere and year after breadfruit planting. Current findings may serve as a reference for future researchers, extension workers, and farmers.