Nutrient availability effects on vesicular‐arbuscular mycorrhizal bell pepper (Capsicum annuum) seedlings and transplants

Abstract

SUMMARYPepper (Capsicum annuum) seeds were sown in nutrient‐poor sand or nutrient‐rich peat/vermiculite amended or not amended with Glomus macrocarpum. The vesicular‐arbuscular mycorrhizal (VAM) seedlings were irrigated with three levels of nutrient solution, and transplanted into four levels of P‐amended soil, each of which was irrigated with two levels of nutrient solution minus P. Mycorrhizal seedlings in sand were responsive to increasing nutrient levels; in nutrient‐rich peat the seedlings did not respond to additional fertilisation. The greatest seedling development accompanied by good fungus colonisation was in nutrient‐poor medium irrigated with the highest nutrient solution tested (18 mM N, 1.2 mM P, and 7 mM K). Non‐VAM plants almost ceased growing between the weeks 4 and 5, whereas VAM plants increased in weight by 41–188%. After transplanting, sand‐grown seedlings benefited from VAM when 300 mg P/kg or more was added to the soil but peat‐grown plants did not. Fruit development was delayed in all non‐VAM plants compared with VAM ones.