Temperature-induced synchronisation of sporophore production in the mushroom Agaricus bisporus

Abstract

Mushrooms were grown at 24° C from the time of casing until sporophore initials had reached 2 mm in diameter. Thereafter, they were either subjected to periods of 2–7 days at 16° C before being returned to 24° C or kept at 16° C continuously. Reducing the length of the period of exposure to 16° C for mushrooms grown in small plastic containers for one flush resulted in an earlier start to picking. However, there were fewer sporophores harvested, but the mean weight per sporophore was increased and crop weight was either not affected or increased. Delaying the time of transfer from 24° C to 16° C until 2 days after the 2-mm stage had little effect except to delay the start of picking. Reducing exposure to 16° C following transfer from 24° C prior to the production of successive flushes on mushrooms grown in wooden trays, 0.5 m 2, gave similar results. However, the total weight of the crop harvested over 6 weeks was reduced. Compared with maintaining a temperature of 16° C continuously from 10 days after casing until the end of 6 weeks cropping, alternating periods at 24 and 16° C resulted in improved synchrony of flushing on replicate trays and the sporophores of each flush were ready to harvest within 2 days. On trays otherwise kept at 24° C, the best synchronisation of flushing resulted from exposure to 16° C for a period of about 6 days prior to the production of each flush.