The impact of Pineapple mealybug wilt-associated virus-1 and reduced irrigation on pineapple yield

The impacts of Pineapple mealybug wilt-associated virus-1 (PMWaV-1) and red uced irrigation on pineapple fruit yield in plant and ratoon crops were eva luated in a field experiment in Hawaii. In the plant crop, PMWaV-1 infectio n and reduced irrigation had no significant effects on fruit weight. In the ratoon crop, plants infected with PMWaV-1 produced smaller fruit than dise ase-free plants and plants that received reduced irrigation also produced s maller fruit than plants that received regular irrigation. Additive effects of PMWaV-1 infection and reduced irrigation were detected; plots of infect ed plants that received reduced irrigation produced the fewest fruit. Frequ ency distributions for fruit size in the ratoon cycle showed shifts to smal ler sized fruit classes when PMWaV-1 or reduced irrigation were present. Es timated yield from combined plant and ratoon crops for infected plants was 6.7% less than disease-free plants when plants received regular irrigation. Reduced irrigation correlated with a 4.2% reduction in estimated yield of disease-free plants, and both infection and irrigation reduction together r educed yield 13.4%. These results show that PMWaV-1 and reduced irrigation can have a negative and additive impact on pineapple fruit production in th e first ratoon.