SEASONAL-CHANGES OF ARBUSCULAR MYCORRHIZAL FUNGI AS AFFECTED BY TILLAGE PRACTICES AND FERTILIZATION - HYPHAL DENSITY AND MYCORRHIZAL ROOT COLONIZATION

Citation
Z. Kabir et al., SEASONAL-CHANGES OF ARBUSCULAR MYCORRHIZAL FUNGI AS AFFECTED BY TILLAGE PRACTICES AND FERTILIZATION - HYPHAL DENSITY AND MYCORRHIZAL ROOT COLONIZATION, Plant and soil, 192(2), 1997, pp. 285-293
Citations number
53
Categorie Soggetti
Agriculture Soil Science","Plant Sciences",Agriculture
Journal title
ISSN journal
0032079X
Volume
192
Issue
2
Year of publication
1997
Pages
285 - 293
Database
ISI
SICI code
0032-079X(1997)192:2<285:SOAMFA>2.0.ZU;2-4
Abstract
The influence of tillage practices on native arbuscular mycorrhizal fu ngi (AMF) was studied in two, consecutive years in eastern Canada, in two 11 year-old long-term tillage-fertilizer experimental field soils, a sandy loam and a clay, growing corn in monoculture. The three tilla ge practices were: 1)conventional tillage (CT; fall plowing plus sprin g disking), reduced tillage (RT; spring disking) and no-till (NT). The corn crop received either inorganic (N and K) or organic (liquid dair y manure) fertilizers. Mycorrhizal hyphal density was estimated from s oil samples obtained in early spring (before disking), at the 12-14 le af stage, at silking, and at harvest. The percentage of corn root colo nization by AMF at the 12-14 leaf stage, at silking and at harvest was also determined. The sandy loam was sampled over two consecutive seas ons and the clay soil over one season. Densities of total and metaboli cally active soil hyphae, and mycorrhizal root colonization were signi ficantly lower in CT soil than in RT and NT soil. Lowest soil hyphal d ensities were observed in early spring. The levels of intra-and extrar adical fungal colonization always increased from spring to silking and decreased thereafter. Spring disking had only a small and transient n egative effect on hyphal abundance in soil. Fertilization did not infl uence mycorrhizal colonization of corn or abundance of soil hyphae in the sandy loam soil, but in the clay soil metabolically active hyphae were more abundant with manure application than with mineral fertiliza tion. In 1992, in both soils different tillage systems had same grain yield, however, in 1993, corn yield was higher in NT compared to CT sy stem.