ISHS Acta Horticulturae 823: XI International Symposium on the Processing Tomato
EVALUATION OF SOIL AND FOLIAR TREATMENTS TO IDENTIFY FACTORS LEADING TO VINE DECLINE DURING FRUIT RIPENING STAGE OF PROCESSING TOMATOES IN THE SACRAMENTO VALLEY |
| Authors: | G. Miyao, R.M. Davis |
| Keywords: | Solanum lycopersicum, yield, California |
| Abstract:
Sacramento Valley processing tomato growers have come to accept declining health of tomato vines during the early fruit ripening period as natural senescence. Many obvious pest problems can contribute to unhealthy plants including the diseases Fusarium wilt or late blight, pressure from aphids or russet mites, and plant nutrient deficiencies such as low nitrogen or potassium. However, we have not attributed a specific causal agent to the widespread and subtler loss of vigor and canopy cover that occurs near the onset of fruit ripening. Beginning in 2005, applied field research in Yolo and Solano counties attempted to identify factors leading to early vine decline disorder by investigating exploratory applications of foliar fungicides, supplemental nitrogen and a soil biocide. High rates of N, P or K have not been successful in managing vine decline. General fungicides, which included strobilurins, have not been effective beyond the obvious target of reducing specific fruit rots or suppressing powdery mildew when severe. Verticillium wilt is the most common factor contributing to poorer plant health, although metham sodium fumigant applications have not always been successful in reducing vine decline. The evaluation is on going with plans to include plant defense elicitors such as Actigard® in combination with general fungicide programs. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
