Record ID No. |
1317 |
Author(s) |
Mortimer P. E., Archer E., Valentine A. J. , 2005 |
Affiliation |
Botany Department, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa. |
Title |
Mycorrhizal C costs and nutritional benefits in developing grapevines |
Source. Vol.(no):Page |
Mycorrhiza. 15(3): 159-165p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Soil plant relations |
Sub-subjects |
Nutrition |
Host |
Vitis vinifera |
Organism |
Glomus etunicatum |
Country |
South Africa, Africa |
Abstracts |
Arbuscular mycorrhizal (AM) C-costs in grapevines were investigated. Dormant vines rely on stored C for initial growth. Therefore AM colonisation costs would compete with plant growth for available C reserves. One-year-old grapevines, colonised with Glomus etunicatum (Becker and Gerdemann), were cultivated under glasshouse conditions. The C-economy and P utilisation of the symbiosis were sequentially analysed. AM colonisation, during the 0-67 day growth period, used more stem C relative to root C, which resulted in lower shoot growth. The decline in AM colonisation during the period of 67-119 days coincided with stem C replenishment and higher shoot growth. Construction costs of AM plants and root C allocation increased with root P uptake. The efficiency of P utilisation was lower in AM roots. The reliance of AM colonisation on stem C declined with a decrease in colonisation, providing more C for the refilling of stem carbohydrate reserves and shoot growth. Once established, the AM symbiosis increased P uptake at the expense of refilling of root C reserves. Although higher root C allocation increased plant construction costs, AM roots were more efficient at P utilisation.. |