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A pot experiment was carried out to investigate the tolerance of cucumber plants (Cucumis sativus L.) to root-knot nematode after inoculation with Glomus intraradices. Plants were inoculated with G. intraradices for four weeks and then transplanted in soil treated with Meloidogyne incognita for a further five weeks. The low phosphorus (P) loamy soil was amended with 50 and 100 mg P kg-1 soil. Mycorrhizal colonization increased shoot dry weight, shoot length, leaf numbers, root fresh weight and shoot P concentration, whereas nematode penetration and reproduction were significantly decreased. Similarly, P fertilization usually increased shoot growth and significantly decreased the number of galls and the number of egg masses and eggs per g root. Our results indicate that inoculation with G. intraradices and P fertilizer confer tolerance of cucumber plants to M. incognita by enhancing plant growth and by suppressing reproduction and/or galling of nematodes during the early stages of plant growth. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted out to investigate the yield and pungency of spring onion ( Allium fistulosum L.) as affected by inoculation with arbuscular mycorrhizal (AM) fungi and addition of nitrogen (N) and sulfur (S) fertilizers. Plants were inoculated with either Glomus mosseae or Glomus intraradices or grown as uninoculated controls. Two levels of N and S were applied to the soil in factorial combinations of 50 and 250 mg N kg -1 soil and 0 and 60 mg S kg -1 soil. Plants were grown in a greenhouse for 25 weeks and then harvested. Mycorrhizal colonization resulted in increased shoot dry weight, shoot-to-root ratio, shoot length, sheath diameter, and phosphorus (P) concentrations. Shoot dry-matter yield was significantly affected by added N, but not by S. Shoot dry weight increased with increasing N supply (except for non-mycorrhizal controls without additional S fertilizer). Shoot total S concentration (TSC), enzyme-produced pyruvate (EPY), and organic sulfur concentration (OSC) in plants inoculated with Glomus mosseae were significantly lower than those of non-mycorrhizal controls, while these parameters in plants inoculated with Glomus intraradices were comparable to or higher than in the controls. Neither N nor S supply affected shoot EPY or OSC, whereas shoot TSC (except in plants inoculated with Glomus mosseae ) and SO 4 2- concentrations were usually significantly increased by S supply. In soil of high S and low P availability, mycorrhizal colonization had a profound influence on both the yield and the pungency of spring onion. [ABSTRACT FROM AUTHOR]

A glasshouse pot experiment was conducted to investigate the impact of inoculation of cucumber at the germination stage with Glomus etunicatum BEG168 on plant yield and incidence of Fusarium oxysporum f.sp. cucumerinum inoculated 28 days after the start of the experiment. Inoculation with the AM fungus decreased both disease incidence and disease index. Mycorrhizal inoculation also increased P concentrations in the cucumber seedlings. The mycorrhizal seedlings had higher concentrations of proline and polyphenol oxidase activity but lower malondialdehyde than non-mycorrhizal seedlings, indicating that AM inoculation may have protected membrane permeability and reduced the extent of the damage caused by F. oxysporum . The results indicate that the mycorrhizal fungus may influence plant secondary metabolites and increase resistance to wilt disease in cucumber seedlings and may therefore have some potential as a biological control agent. [ABSTRACT FROM AUTHOR]