Growth of asparagus in a commercial peat mix containing vesicular-arbuscular mycorrhizal (VAM) fungi and the effects of applied phosphorus

Abstract

Commercially prepared, peat-based mycorrhizal inocula were studied for growth effects on asparagus grown under greenhouse and field (fumigated) conditions. The fungi tested were Glomus clarum (GC), G. intraradix (GI), G. monosporum (GM), G. versifomre (GVR) and G. vesiculiferum (GVS). GI significantly increased plant dry weight in the greenhouse and the field. Survival of mycorrhizal tissue-cultured transplants after 14 months in the field was increased by twofold over the control. In a second experiment asparagus was grown from seed in the greenhouse in peat inoculated with a G.fasciculatum-like fungus (GF), GI and GVR with applied P levels of 0, 50, 100 and 150 ppm and harvested after 13 and 17 weeks. Total dry weights of GI and GVR plants were significantly increased over those of the control and GF. Dry weight in this second experiment was positively correlated with root colonization. Root colonization at week 13 was slightly reduced with increasing levels of applied P, but not at week 17. The data suggest that the increased growth of mycorrhizal plants was not related to an increase in tissue P concentration, since there was no growth response to applied P and tissue P concentration in the mycorrhizal plants was lower than in the non-mycorrhizal plants.

Production of Prenuclear Minitubers of Potato with Peat‐Based Arbuscular Mycorrhizal Fungal Inoculum

“…In contrast, the AM beds in this study showed significantly increased yields without an associated increase in plant P concentration. Similar growth increases in the absence of P concentration effects were reported in sweetgum (Liquidambar styraciflua L.) (Schultz et al, 1979), and in asparagus using the same AM inoculum as we have used here (Pedersen et al, 1991). In a 1994 report, Volpin et al showed an AM-induced increase in isoflavonoid production in alfalfa (Medicago sativa L.) under very low levels of hyphal colonization in the root tissue.…”

“…The effects of peat-based AM inoculum have been investigated in soilless substrates commonly used in the production of many horticultural crops (Ponton et a!., 1990;Pedersen eta!., 1991). Mycori-Mix (Premier Peat Moss, Riviere-du Loup, Quebec, Canada), a commercial peat-based AM inoculum, has been tested on asparagus (Asparagus officina/is L.) (Pedersen et a!., 1991) and leek (Allium porrum; syn. A. ampeloprasum L. Porrum group) (Caron and Parent, 1988), and shown to enhance AM colonization and increase yield.…”

Influence of Formononetin and NaCl on Mycorrhizal Colonization and Fusarium Crown and Root Rot of Asparagus

“…All plots were treated with N (as NH 4 NO 3 ) at 56 kg/ha and K (as K 2 SO 4 ) at 50 kg/ha at planting and in spring of 2000 and 2001. Phosphorus was not applied because soil tests revealed sufficient P and because high P conditions inhibit VAM colonization (30). Weeds were removed by hand in 1999.…”

Strategies for Mycorrhizal Inoculation of Six Annual Bedding Plant Species

“…The benefit from mycorrhizal colonization may be related to the amount of colonization established early in the seedling stage of plant growth (Boswell et al, 1998;Pedersen et al, 1991). However, some attempts to colonize roots growing in soilless media have resulted in low levels of colonization (Biermann and Linderman, 1983a;Johnson and Hummel, 1986;Nemec, 1987;Pedersen et al, 1991). There are, therefore, few documented examples of the successful use of VAM fungi in horticultural production, particularly in floriculture (Chang, 1994;Miller et al, 1986).…”