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Determining the physiological and genetic mechanisms of initiation to control mushroom population densities - HH1334SMU

Achieving the correct number of initials on the casing layer is critical in obtaining the maximum yield of quality mushrooms. The mechanism by which the casing layer promotes initiation is not established. A tentative hypothesis regarding the function of the casing layer is that initiation is controlled by the production of self-inhibitory compounds by the Agaricus mushroom mycelium. Lowering the level of this (these) compound(s) to below a threshold level is probably necessary for initiation to occur. The threshold level may be achieved through the metabolism of these compounds by the casing microflora (Pseudomonas putida isolates), or by adsorption on specific casing materials.
This project will establish whether the tentative hypothesis is a correct interpretation of the mechanism of initiation, and thereby identify several pathways by which the population of initials on the casing layer can be manipulated. The proposed work is fully consistent with the MAFF policy objectives in HH13 'Environments for protected cropping'. In particular, the project will improve the ability of growers to optimise efficiency of production in the use of picking labour and substrates, to manipulate cropping patterns, and to improve crop quality and uniformity.
To improve mushroom production, quality and ease of picking by identifying the physiological and genetic mechanisms which control initiation and mushroom population densities.
0.1 Isolate specific compounds from mushroom casing through chemical analysis.
0.2 Test whether the compounds identified are inhibitory, stimulatory or neutral towards initiation.
0.3 Quantify differences between Pseudomonas putida isolates with respect to metabolism of inhibitory or stimulatory compounds and Agaricus initiation.
0.4 Compare plasmid profiles of stimulatory and non-stimulatory bacteria.
0.5 Quantify inhibitory compounds in A. bisporus isolates exhibiting different initiation behaviours (B430 and mass and minimal initiation isolates).
0.6 Technology transfer: Prepare scientific papers, industry publications and presentations (at least two of each) and formalise commercial channels for on-farm trials and exploitation of products.
Project Documents
• Final Report : Determining the physiological and genetic mechanisms of initiation to control mushroom population densities   (620k)
Time-Scale and Cost
From: 2001

To: 2004

Cost: £242,564
Contractor / Funded Organisations
Horticulture Research International
Organic Farming              
Fields of Study