2012 Annual Report
1a.Objectives (from AD-416):
1) Evaluate P. penetrans population dynamics and fruit yield in existing fields of raspberry varieties ‘Meeker’, ‘Chemainus’, ‘Saanich’ and ‘Cascade Bounty’.
2) Evaluate plant growth, nematode population densities, and yield in plots within fumigated and non-fumigated sections of newly planted fields.
3) Extend knowledge developed above to the raspberry growing community through field days, commission newsletters, and extension publications.
1b.Approach (from AD-416):
In established red raspberry fields, a post-plant nematicide will be applied to replicated plots to suppress P. penetrans. We will determine soil physical and chemical properties, including percentage clay, loam, organic matter and sand, and soil pH. We will sample roots and soil in treated and non-treated plots twice per year to document P. penetrans population dynamics (in soil and roots), and we will evaluate plant growth (cane height and pruning weights) and plant yield (three or four harvests per summer) in the same plots.
In addition, P. penetrans-infested fields scheduled for fumigation and replanting will be identified. Fumigated and non-fumigated areas within these fields will be established and raspberries will be planted within each area in which to monitor nematode population dynamics and plant parameters on different varieities. In another field, we will establish replicated small plots of ‘Meeker’, ‘Chemainus’, ‘Saanich’ and ‘Cascade Bounty’ in the fumigated area, and similar replicated plots in the non-fumigated area. We will evaluate P. penetrans in roots and soil, plant growth and plant yield as described above.
All findings will presented to growers through field days, publications, and workshops. Upon conclusion of this project an IMP recommendation fact sheet will be prepared.
The plant-parasitic root lesion nematode Pratylenchus penetrans, has been identified by the Washington red raspberry commission as a major production constraint to their industry. The red raspberry industry is at increased economic risk from P. penetrans because new federal regulations will soon make pre-plant soil fumigation prohibitively difficult and expensive for many growers, and few post-plant nematode management options exist. Field trials were established to determine whether raspberry varieties differ in their susceptibility to P. penetrans,and identify the conditions under which P. penetrans must be managed. One set of trials were established in existing raspberry fields; plots are being protected from nematodes with a post-plant nematicide and nematode population dynamics and raspberry yield of these plots compared to nontreated plots. A second set of trials were established in grower fields prior to planting by treating part of the field with a fumigant and leaving another part nontreated; raspberry establishment, nematode population dynamics, and yield will be evaluated over time. Both sets of trials will be monitored over a 3 to 4 year period. This research was conducted in support of objective 308 1A: Development of New Technologies for Alternatives and Integration into Commercial Crop Production Systems Currently Dependent upon Methyl Bromide Soil Fumigation.