Use of hydrogel as a sticking agent and carrier for vesicular-arbuscular mycorrhizal fungi

Abstract

Natrosol®, a non-ionic, water-soluble polymer, was used as a sticking agent for direct inoculation of spores of Glomus etunicatum Becker & Gerdemann on roots of bahiagrass ( Paspalum notatum Flugge). After 16 wk in aeroponic culture, roots were 67, 68, 55, 54, and 41% colonized with the VAM fungus at distances 0–6, 6–9, 9–12, 12–15, and 15–18 cm below the crown, respectively. Natrosol was also tested as an inoculum carrier for VAM fungi in soil. Colonized roots or spores of up to four VAM fungi were mixed with Natrosol and injected next to sweet potato ( Ipomoea batata (L.) Lam. cv. White Star) shoot cuttings. Natrosol increased the number of penetration points at 4 wk when the inocula were spores, but had no effect when the inocula were colonized roots. Natrosol had no effect on spore germination nor on root colonization at 14 wk, but increased both the proportion of root length with root hairs and total root length.