MSc.

The present investigation on “Standardization of techniques for cultivation of Tricholoma giganteum (Massee) in Kerala” was conducted at the Department of Plant Pathology, College of Agriculture, Vellayani, during 2012-2013. The aim of the study was to explore the possibility of cultivation of Tricholoma giganteum (Massee) on readily available cheap substrates and to develop a package for commercial cultivation in Kerala.

Mushrooms were collected from different parts of Trivandrum districts before and after the South West and North East monsoons. Preliminary trials laid out showed that isolate 1 was the best out of 4 isolates which was sent to DMR. This isolate with accession number DMRO- 462 was used for further studies.

Tricholoma has a convex pileus, off white to creamy white in colour, fleshy in texture and with a stout hairy stipe.

Cultural studies conducted showed that the isolate attained full growth in petridish in 14 days on oat meal agar and least growth was found in carrot agar medium. Out of six carbon sources dextrose was found to be best for the radial growth of Tricholoma, least growth was found in galactose. Among the seven nitrogen sources used to study the radial growth of Tricholoma in petridish beef extract was found to best and least in ammonium nitrate. Temperature of 35 ⁰C, fluorescent light conditions and pH8 were found to be the best for the growth of Tricholoma giganteum.

Evaluation of six different spawn substrates showed that paddy grains was best spawn substrate since complete spawn run was attained in two weeks. Regarding yield studies beds laid out with wheat grain spawn gave highest yield of 833.33 g / bed. Saw dust took maximum time for spawn run and lowest yield was also recorded in it.
Six different locally available cheap substrates viz., paddy straw, sugarcane bagasse, saw dust, coir pith compost, spent mushroom substrates and coir pith + paddy straw were used for the cultivation of Tricholoma giganteum. Highest yield (694.50 g) was found to be in beds prepared from paddy straw and lowest yield (199.50 g) was observed in beds laid out with coir pith + paddy straw as substrate.

Out of the casing materials tried vermi compost was found to be the best. Lowest yield was found be in beds cased with red soil + sand.

Analysis of nutrient composition of Tricholoma giganteum indicated that, the moisture content, protein, fat, carbohydrate, ash and fibre content was found to 87.46 %, 23.20 %, 2.60 %, 10.10 %, 11.46 % and 19.01 % respectively.

The shelf life of fresh mushroom was high (7 days) when stored in polypropylene cover without perforation in refrigerated condition. For mushroom dried in hot air oven the shelf life was found to be 60 days.

Pests like sciarid flies and staphylinid beetle were prevalent after the second harvest only. Coprinus, cob web (Cladobotryum dendroides) and Trichoderma causing decay of the fruiting body was observed in Tricholoma giganteum beds when temperature and relative humidity was high.

Results of organoleptic studies revealed that Tricholoma has high cooking quality and overall consumer acceptability was good. Cutlets were found to be the best when consumed by the panel of judges followed by payasam. The overall acceptability of soup made out of dried mushroom powder was comparatively poor.

Based on the results obtained during the investigation it can be concluded that Tricholoma is a new summer edible mushroom most suited for the Kerala conditions. The technology of cultivation of Tricholoma on paddy straw substrate using wheat or paddy spawn and vermi compost as casing material can be recommended as a suitable domestication package which will be transferred to the farmers along with the release of this mushroom variety.