Effects of mulching with vineyard and winery waste on soil fungi and botrytis bunch rot in Marlborough vineyards

Abstract

Field trials were established in four vineyards in January 1999 to evaluate the effects of four mulch mixtures containing vineyard and winery wastes on different soil and plant parameters The effect of mulch treatment on numbers of colony forming units of soil fungi was assessed using soil dilution plating During 3 years (19992002) the numbers of soil fungi tended to be higher in soil sampled from under mulchtreated plots than in soil from nonmulched plots The effect of mulches on incidence and severity of botrytis bunch rot (caused by Botrytis cinerea) was also investigated Incidence of the disease was not increased by the mulch treatments and in some instances bunch rot incidence was less on grapes from mulched plots than unmulched plots