Market pathology of Faizabad Part 1 - Virulence of pink bitter core rot of Kamarakh Averrhoa carambola L

Extensive survey of Faizabd (U.P.) vegetable and fruit market, during August-November 1972, showed the virulence of this disease. Almost all the fruits were infected and become unfil for consumption. The first apperance of the disease was recorded in August 1972 when the magnitude of infection was low. In September the infection was severe and it was recorded on more than 80 per cent fruits in all lots. In the succeeding months, however, the severity of infection exhibited a decreasing tendency and during November in all the lots it was below 30 per cent (Table). 

In most of the cases, the lesions consumed one-third to three-fourth part of the fruit rendering them useless. The disease starts from any point of injury on the surface of the fruits. The first symptom is a brown lesion, which radiates from the point of infection with invasion of tissue and instead of gradually spreading over the epidermis goes deep into the fruit and decomposes nearly the entire flesh, simultaneously producing a soft watery light brown fluid (Fig.)Thereafter, a massive production of pink coloured conidia of T. roseum becomes visible on the surface of the fruits. In the advanced stage, a discoid sporulation of light pink conidia appears. The pink colouration and powdering extreme with age.

Sugar nad organic acids, viz., citric and tartaric acids, are the main constituents of the fruit that are readily utilized by Trichothecium roseum. The present survey shows that the extent of damage to fruit depends upon the duration of the storage and environmental condition, particularly the tempereture prevailing during marketing and this is tyhe probable reason for high disease index during the September 1972 and comparatively lesser in succeeding months (Table). 

In fruits infected with T. roseum, secondary organisms become quickly established producing light brown fluid. This secondary organism is supposed to be the bacterium that appeared on the tissues killed by the advanced of the fungus towards the interior of the fruits emitting foul odour.  

Cite this as: Kanaujia R.S. and C.S. Singh (1974): Market pathology of Faizabad Part 1 - Virulence of pink bitter core rot of Kamarakh Averrhoa carambola L. TECHNOLOGY. 11 (2&3): 305-306.