The goal of our research and outreach project was to enhance sustainability of muskmelon disease, weed, and insect pest management while reducing pesticide inputs. Muskmelon, a key high value crop, relies heavily on costly synthetic pesticides and fertilizers that endanger grower and consumer health, kill non-target organisms, and pollute the environment.
Our research clearly demonstrated the effectiveness of row covers in reducing insecticide use, decreasing the incidence of bacterial wilt, and increasing muskmelon yields. This outcome provides muskmelon growers with a practical alternative for control of bacterial wilt that is likely to improve profitability and reduce insecticide use compared to conventional management practices. In addition, cooperating commercial muskmelon growers successfully utilized row covers in their own operations. These results are published in a peer-reviewed journal and in extension and trade-journal publications. We also presented these results to growers at field days and workshops.
Using the Melcast warning system with input weather data from either on-site weather sensors or commercially available site-specific estimates reduced fungicide sprays compared to conventional, calendar-based spray program and provided equivalent control of anthracnose, caused by Colletotrichum orbiculare. These findings benefit growers by providing a convenient, reliable alternative to using on-site weather sensors in implementing a disease-warning system. Weather sensors and dataloggers are expensive, require regular maintenance, and demand time to download weather data. Growers can obtain site-specific weather estimates far more easily, via e-mail or the Web, than making on-farm measurements; our work shows that these data will reduce fungicide sprays while providing good disease control.
Our weather modeling work showed the feasibility of using near-field weather sensors as another alternative to within-field sensors that are subject to damage from tillage and other agronomic activities. The near-field sensors provide another option for growers to make implementation of disease-warning systems more convenient and practical. Three publications in peer-reviewed research journals resulted from this effort.
We experienced problems with current strategies to use trap crops to reduce the incidence of bacterial wilt in muskmelons by reducing cucumber beetle feeding. We found that trap crops commonly used may not be the most effective species and cultivars, so we devised a Year 3 trial to determine which species and cultivars might work better. Our results point to several cucurbit varieties that have good potential to serve as effective, season-long trap crops. Future trials should deploy these trap crops to test their ability to reduce bacterial wilt.
Our experiments with using a hairy vetch-rye cover crop to control weeds in muskmelon gave inconsistent results, with weeds sometimes becoming a major problem in these trials. An unanticipated disadvantage of this strategy in Iowa is that muskmelons cannot be planted into the cover crop until the vetch flowers; this occurs in mid-June in Iowa, which means that melons will be harvested from these plots too late (e.g., late August) to fetch adequately profitable prices at local markets or supermarkets. We concluded that the hairy vetch/rye strategy may be better suited to warmer climates than Iowa, and that further experimentation is needed to develop an optimal method for pushing the cover crop down to soil level before transplanting melons.
OBJECTIVE 1: Suppress bacterial wilt and cucumber beetle feeding injury on muskmelons as effectively as conventional insecticide-based method by integrating mass trapping, trap crops, row covers, neem, and kaolin clay.
OBJECTIVE 2: Alternative strategies against the fungal disease complex of anthracnose, gummy stem blight, and Alternaria leaf blight.
OBJECTIVE 3: Evaluate the ability of a hairy vetch-rye cover crop to suppress weeds, reduce applications of conventional herbicides, and add nitrogen to soils.
OBJECTIVE 4: Combine the most promising component strategies from Objectives 1-3 into systems-level strategies that integrate weed, insect, and disease management.
OBJECTIVE 5: Document economic costs and benefits of these new management tactics in comparison to conventional practices.
OBJECTIVE 6: Transfer the project’s findings to muskmelon growers through on-farm demonstration trials, a WWW site, quarterly newsletter articles, presentations at regional grower meetings, annual field days, press releases, and an extension bulletin.