MSc

Fungi play an inevitable role in the biodegradion of leaf litter. The present investigation was carried out to assess the role of mycoflora in the degradation of jack and mango in the identified homestead. Many litter decomposing fungi were isolated from both jack and mango leaf litter. The period of study was during September 1993 to March 1995.
Nine genera of fungi were frequently isolated from mango leaf litter of which eight belonged to Deuteromycotina, and one to Zygomycotina.
Thirteen genera of fungi were frequently isolated from jack leaf litter at different stages of decomposition, of which twelve belonged to Deuteromycotina and one to Zygomycotina.
The common primary colonizers isolated were Aspergillus niger, A. flavus, Penicillium citrinum, P. oxalicum, P. islandicum, Pestalotia palmarum, Colletotrichum gloeosporioides, Trichoderma viride and T. harzianum. The common fungi isolated from decomposing leaf litter of both trees were Mucor hiemalis. Members of Basidiomycotina were also isolated from decomposing leaf litter.
At higher temperature the fungal counts were lower in the fresh litter but higher in decomposed leaf litter of both trees. At higher rainfall the fungal count was more in surface litter but the same was lower in decomposed leaf litter.
Identification and description of 30 fungal species were carried out following slide culture technique.
The weight loss was more at 450C, when compared with weight loss at 350C and 250C of both mango and jack leaf litter. The weight loss was more pronounced in the field condition as against laboratory conditions. Higher temperature and higher rainfall led to an increased rate of litter decomposition.
The decay process was faster in jack indicating the higher efficiency of decomposition in the case of jack litter as compared with mango. The decomposition constant (K) for jack was 1.52 as against a lower K value of 1.03 for mango. This indicates the faster decomposition of jack leaf liter when compared with mango litter.
Trichoderma viride, Trichoderma harzianum, Chaetomium globosum, Verticillium theobromae, aspergillis niger, A. ochraceous, A. tamari, Penicillium oxalicum were found to be efficient in utilizing cellulose as their sole carbon source.
There was an increase in nitrogen and ash content in the decomposing leaf litter when compared with fresh litter. The carbohydrate content was more in fresh litter and the same decreased with the progress of decomposition.
Inoculation studies with common plant pathogens isolated from jack and mango leaf litter were done and Colletotrichum gloeosporioides was found to infect mango and jack leaf litter producing characteristic symptoms on mango and jack.