PhD

he present study entitled “Characterization and exploitation of jelly
mushrooms (Auricularia spp./ Tremella spp.)” was carried out in College of
Agriculture, Vellayani during 2014-2017, with the objective of standardization of
techniques for production of jelly mushrooms (Auricularia spp./ Tremella spp.) in
agricultural wastes and to study their morphological, physiological and cultural
characteristics as well as nutritional and organoleptic qualities.
Survey was conducted in ten different locations of Thiruvananthapuram and
Kollam districts of Kerala during 2014-2016. Sporocarps of Auricularia spp. and
Tremella spp. were collected from tree stumps, predominantly Mango, Coconut,
Drumstick, Teak wood and Rubber. All the mushrooms collected from all the
locations were gregarious in nature and lignicolous in habitat. Morphological
studies of jelly mushrooms showed that the sporocarps were light brown to dark
brown in colour with incurved margin, ear shaped, soft and velvety in texture and
devoid of stipe.
The internal stratification of hyphae showed eight different
zonations. Basidiospores were hyaline, oval and sub cylindrical to cylindrical
shaped.
Two fast growing isolates selected based on the time taken for complete
mycelial growth and nature of mycelial growth, designated as A1 and A2 were
sent to Directorate of Mushroom Research, Solan for identification. These were
identified as Auricularia polytricha (Mont.) Sacc. (Accession number of A1 was
DMRO-825 and A2, DMRO-826).
The maximum mycelial growth was recorded on malt extract agar medium
and a temperature of 250C, pH 7 and light conditions were found favourable for
mycelial growth. Evaluation of different substrates for spawn production revealed
that paddy grain was the best substrate followed by sorghum. Rubber sawdust
spawn recorded maximum keeping quality. Malt extract broth was found to be
the best for submerged culture production of both A1 and A2.
Evaluation of different substrates for mushroom production revealed that
rubber sawdust was the best substrate for cultivation which recorded maximum
Biological Efficiency (BE) of 14.8% for A1 and 12.2% for A2. The minimum
time for spawn run was taken by paddy straw and the maximum was taken by
neopeat. Major insect pests observed were Megaselia sp., Seira sp. and
Staphylinus sp. The competitor moulds observed were Coprinus sp, Aspergillus
spp., Penicillium sp. and Trichoderma sp. Among the different amendments,
wheat bran (2.0 and 4.0 %) and groundnut cake (2.0%) were found to be the best
for enhancing the growth parameters whereas, rice bran (2.0% and 4.0%) was the
best for increasing yield parameters.
Analysis for the proximate constituents in A. polytricha (A1 and A2)
revealed that it contained appreciable amount of carbohydrate (47.1 and 48.8%),
protein (18.06 and 20.75%), polyphenols (9.53 and μg), fibre (17.69 and 15.49%),
total anti oxidants (116 and 74μg), β carotene (0.178 and 0.150 μg) and the
energy value was 251.49 and 264 respectively. Sensory evaluation of mushroom
products made from A. polytricha (A1 and A2) indicated that mushroom tomato
sauce scored maximum for overall acceptability. Under refrigeration (40C) in
perforated poly propylene covers mushrooms could be kept fresh for three days.
Indoor cultivation of both A1 and A2 showed significant results for growth
parameters as well as yield parameters compared to outdoor cultivation.
Comparative performance of A. polytricha with two ruling mushrooms of Kerala
namely oyster mushroom (Pleurotus florida (Mont.) Singer.) and milky
mushroom (Calocybe gambosa (Fr.) Donk.) indicated that oyster mushroom took
minimum days for spawn run, pinhead formation and first flush compared to
milky mushroom and A. polytricha. Milky mushroom recorded highest BE
(66.1%) compared to others.
Studies on medicinal activities of A. polytricha indicated that it possessed
anticancerous activities for cervical, colon and liver cancer cell lines and higher
activity was recorded in 100 μg/ml concentration.
Based on the results of present investigation, A. polytricha can be cultivated
successfully in tropical areas on locally available materials. Paddy grain was the
most suitable substrate for spawn production and Rubber sawdust amended with
2% rice bran, the most suitable growing medium. Mushrooms possessed
significant nutritional and medicinal activities. The findings of the above
investigations recommend the adoption of a suitable cultivation package for jelly
mushrooms (A. polytricha), a highly prized mushroom.