Using Biosynthesized Zinc Oxide Nanoparticles to Alleviate the Toxicity on Banana Parasitic-Nematode

Abstract We appraised the use of zinc oxide nanoparticles, (ZnO-NPs) and zinc oxide bulk (ZnO-bulk) or zinc acetate, as a natural nematocide, alone or in combination with oxamyl in vitro and in vivo trials in order to improve systems for root-knot nematode (RKNs) control in banana plants. Especially, ZnO-NPs were biosynthesized from the alga, Ulva fasciata. In general, all applications of ZnO-NPs were more effective to control RKNs than ZnO-bulk as well oxamyl alone (chemical control). In in vitro conditions, ZnO-NPs with oxamyl showed 98.91% second stage juveniles2 (J2s) mortality of Meloidogyne incognita after 72 hrs, while 72.86% mortality was observed at the same NPs treatment without oxamyl at the same exposure time. The same treatment was the most effective in diminution of J2s community (82.77%) in soil and galls number (81.87%) in roots under in vivo conditions. In contrast, the highest weight and height of the shoot was observed in Zn-bulk treatment in combination with oxamyl as well oxamyl only (nematocides check). Scanning electron microscopy (SEM) reports displayed the distributions and accumulations of ZnO-NPs on the nematode (J2s) body under direct exposure, which might be the reason of NP-mediated toxicity and disruption for M. incognita.