IMPACT OF THE ROTTING PROCESS OF BIODEGRA DABLE MATERIAL OF HOUSEHOLDGARBAGE ON THE SURVIVAL OF PHYTOPATHOGENIC ORGANISMS AND OF TOMATO SEEDS

The sanitary impact of the rotting process of biodegradable material o f household garbage (kitchen and yard waste) on some phytopathogenic o rganisms and on tomato seeds was investigated in triangular-shaped win drows (outdoor composting, regular turning). The survey was carried ou t during the winter season 1990/91 and the summer period 1991. Tempera ture, associated with an adequate moisture content, was the major leth al constraint for sclerotia of Sclerotinia sclerotiorum, egg sacks of Meloidogyne incognita, tobacco mosaic virus and for tomato seeds (Lyco persicon lycopersicum). In the central zones of the windrow, temperatu re met in both seasons the required minimum temperatures of 55 to 65-d egrees-C prevailing 12-21 days to ensure elimination of pathogens. In each of four conducted long-term trials, the measured temperatures rev ealed ideal rotting conditions. Differences from optimum were caused i n winter by low outside temperatures (down to -16-degrees-C), in summe r by periodically limited precipitation. Within the inner zones of the windrow, none of the tested organisms, which had been directly expose d to the influence of the decomposition conditions, survived the study period. The final results gained in the outer zone varied according t o the tested organism. Thus, sclerotia of S. sclerotiorum were complet ely killed. With regard to M. incognita, neither the test for survivin g larvae applied in winter showed positive results, nor did the test f or plant infection ability used in summer. Tobacco mosaic virus lost i ts infectiosity excepting a single positive result in winter. To the c ontrary, tomato seeds retained their emergence ability in both seasons with a single exception in winter. The heat resistance of the test or ganisms omitting the tabacco mosaic virus was examined in supplementar y laboratory tests up to 91 days.