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Cashew is an important cash crop in India but the incidence of diseases incur considerable losses in cashew plantations leading to reduction both in terms of quality and quantity. The present investigation was to study the fungi associated with cashew plant in Odisha in view of the warm and humid climate. Isolation, identification, pathogenicity test and nutritional study of the test fungi as well as the control was undertaken in vitro. The result of the study revealed that seven species of fungi namely Pestalotiopsis palmarum, Phyllosticta sp., Colletotrichum gloeosporioides, Botryodiplodia theobromae, Fusarium oxysporum, Rhizoctonia solani and Chaetomium brassiliense were responsible for various diseases. Pestalotiopsis palmarum and Phyllosticta sp.were found to cause leaf spots; Colletotrichum gloeosporioides causing leaf spot, die back and gummosis of stem; Botryodiplodia theobromae causing inflorescence blight, die-back of twigs and stem gummosis; Fusarium oxysporum and Rhizoctonia solani causing seedling blight and root rot and Chaetomium brassiliense being responsible for causing storage rots in cashew nuts. Pathogenicity test revealed that all the test fungi were pathogenic to their respective host parts except stem gummosis. The results of the nutritional study on different solid media indicated that Malt Extract Agar medium supported the maximum mycelial growth of all the test fungi except Chaetomium brassiliense and Phyllosticta sp. In-vitro antifungal activity of some selected fungicides indicated that Bavistin could control all the pathogenic fungi by 100 %. Further studies can recommend suitable control measures for the farmers and commercial growers.

A survey of fungi associated with post-harvest deterioration of Colocasia esculenta L. tubers was conducted in Bhubaneswar city, Odisha, India, in 2014-15. Rotten Colocasia esculenta L. tubers collected from five different markets: Unit-I market, Sahid Nagar, V.S.S. Nagar, Palasuni and Rasulgarh market located in Bhubaneswar city. The following fungi; Aspergillus niger, Aspergillus flavus, Geotrichum candidum, Rhizopus oryzae were isolated from rotten tubers. Of these, Rhizopus oryzae and Geotrichum candidum has highest percentage frequency of occurrence followed by Aspergillus niger while Aspergillus flavus has the least percentage frequency. Pathogenicity tests revealed that all the isolated fungi were pathogenic on Colocasia esculenta L. tubers; however Rhizopus oryzae and Aspergillus flavus were most pathogenic leading to rapid disintegration of the infected tubers within 20 days of inoculation. While Aspegillus niger was the least pathogenic. The use of improved Colocasia esculenta L. varieties, good storage facilities and adequate control measures need to be encouraged in order to reduce storage rot of Colocasia esculenta L. tubers.

Hyptis suaveolens (L.) Poit. is an invasive alien weed commonly known as "Bana tulsi" in Odisha belonging to the family Lamiaceae and widely distributed in different parts of India. The leaves of the plant have been reported to be used as stimulant, carminative, sudorific and also as a cure for parasitic cutaneous diseases besides the crude leaf extract is reported to be used against colic and stomach-ache. The leaves are the source of different alkaloids, terpenes and volatile oils having allelopathic effect. In view of this the present work was carried out with an aim to investigate the allelopathic effect upon germination of rice (Oryza sativa L.). The result indicated that the higher concentration of the leaf leachate could decrease the percentage of germination besides identified as a potential bio-herbicide.

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