Performing Department
(N/A)
Non Technical Summary
This ARDP Research-led, multi-institutional, and state collaborative project addresses CPPM focus area, plant protection tools, and tactics. In the Delmarva, cucurbit production is often interrupted by the damage inflicted by herbivores such as the squash bug, squash vine borer, and striped and spotted cucumber beetle. The long-term goal of this project is to expand cucurbit production in Delmarva and ensure that it remains profitable for farmers of all socioeconomic status. Specifically, we propose to develop effective trap cropping to lure pests away from the main cash crop and companion planting schemes to reduce and repel pest colonization of the cash crop and enhance the efficacy of their biocontrol agents. We hope these management tactics will be useful to diverse groups of producers. We also anticipate that findings from the various objectives will result in developing a future push-pull strategy as another IPM tool. Specific objectives of this project include: 1) determining the host plant preference of cucumber beetles, squash bugs, and vine borers, 2) identifying headspace volatiles of select squash varieties (from obj. 1) and accessing their behavioral impact on squash bugs and cucumber beetles, 3) evaluating companion plants for their ability to reduce insect pests and augment and enhance the efficacy of natural enemies, and 4) establishing research/demonstration plots in farmers' and university fields to showcase some of the best treatments determined from objectives 1-3. We anticipate finding trap and companion crops that can be used to reduce cucumber beetle, squash bug and vine borer damage to the main crops, and efficient trap and companion crop schemes that can be used to reduce pesticide use in cucurbit production and consequently minimize adverse environmental effects and reduce nontarget impacts on biodiversity, biocontrol agents and pollinators.
Animal Health Component
60%
Research Effort Categories
Basic
30%
Applied
60%
Developmental
10%
Goals / Objectives
The long-term goal of this project is to expand cucurbit production in Delmarva and ensure that it remains profitable for farmers of all socioeconomic statuses. Specifically, we propose to develop effective trap cropping to lure pest away from the main cash crop and companion planting schemes to reduce and repel pest colonization of the cash crop and enhance the efficacy of their biocontrol agents. It is our hope that these management tactics will be useful to diverse groups of producers (e.g., small, beginner, socially disadvantaged, minority, conventional, organic, and large-scale). We also anticipate that findings from the various objectives will result in the development of a future push-pull strategy as another IPM tool.Objectives: Determine the host plant preference of cucumber beetles, squash bugs and vine borers. (Drs. Zebelo and Tolosa, and graduate students)Identify headspace volatiles of select squash varieties (from obj. 1) and access their behavioral impact on squash bugs and cucumber beetles. (Drs. Zebelo, Tolosa and graduate students)Evaluate companion plants for their ability to reduce insect pests and augment and enhance the efficacy of natural enemies. (Dr. Hooks and graduate student)Establish research/demonstration plots in farmers' and university fields to showcase some of the best treatments determine from objectives 1-3. (Drs. Burton, Zebelo, Tolosa, Hooks and graduate students)
Project Methods
Objective 1 (Research). Determine the host plant preference of squash bugs and vine borersMultiple-choice experiments: Three greenhouses will be equipped with a screen cage (3×4 m) considered a replicate. In multiple-choice experiments, the potted host plants will be arranged equidistantly in a rectangular fashion around the center of the cage so that each host plant type occupy one-fourth of the rectangle to simulate most squash farms. Two separate host preferences experiments will be conducted to evaluate seven squash cultivars, including butternut, Hubbard, Yellow straight-neck, Crooked-neck, Desert, Yellowfin, and Tempest. Fifty mated female squash bugs per replicate will be released at the center of the screen house, and their oviposition preference will be evaluated. The number of egg masses per plant will be recorded at 24-hour intervals for 10 days, and eggs will be removed from test plants. Striped and spotted cucumber beetles will not be a part of this choice experiment. Striped cucumber beetles lay their eggs in the soil at the base of the host plant and spotted cucumber beetle also oviposits its eggs into the soil. The average number of egg masses per plant will be compared using repeated measures ANOVA followed by Tukey-Kramer HSD test (P < 0.05). Similarly we will do a lso two-choice experiments . Host preference study for squash vine borer: Squash varieties used for the squash vine borer host preference study will be planted in pots in the greenhouse and transplanted into the field in late May or early June at the UMES agricultural experiment station. Methods will be similar to Howe and Rhodes [16]. For each plot, 20 squash plants will be planted per row and each row will contain one of the seven cucurbit varieties. Thus, there will be seven rows and a total 140 plants per plot. Each plot will be replicated a minimum of four time. Squash vine borer larval injury ratings will be recorded at weekly intervals initiating two weeks after transplanting. Numerical damage ratings will be made on a scale of 0 to 5 as followed: 0 = no injury, 1 = petiole boring only, 2 = active larval boring in stem with light injury (with green sawdust), 3= part of the plant started wilting, 4 = increasing levels of stem injury by normal larvae, and 5= main stem completely severed by boring larva. The lack of plant injury will imply low preference for oviposition and larval acceptability. However, borer oviposition and evidence of tunneling by larvae in other plants will be considered "prima facie" evidence of host acceptability. Petiole injury without larval establishment will be interpreted as oviposition on an unsatisfactory host plant. The percentage of plants damaged by squash vine borer larvae per row will be averaged and compared relative to butternut squash damage. Damage ratings will be recorded and analyzed to identify the most attractive host.Objective 2 (Research). Identify headspace volatiles of select squash varieties (from obj. 1) and access their behavioral impact on squash bugs and cucumber beetles.Volatile collections from host plants: Headspace volatiles will be collected from the above-selected whole plants using standard protocols (e.g., Zebelo et al., 2017).Objective 3 (Research). Evaluate companion plants for their ability to reduce insect pests and augment and enhance the efficacy of natural enemies. Companion plant evaluation: Field studies will be conducted at the Central Maryland Research and Education Center in Upper Marlboro, MD during two growing seasons. Individual plots will be ~ 12.2 m ×10.1 m with buffer areas of at least 9.1 m between plots. Treatments will be arranged in a randomized complete block design with four replicates and include summer squash: 1) interplanted with nasturtiums (Tropaeolum sp), 2) interplanted with marigold (Tagetes erectaL), 3) grown in monoculture with insecticide sprays; and 4) grown in monoculture with no insecticide (control). The companion plant plots will be arranged such that each squash plant within the interior rows is near two companion plants. The nasturtium, marigold and squash will be seeded in the greenhouse and transplanted in the treatment plots. The systemic insecticide (Admire Pro) will be applied at transplanting and the foliar insecticide carbaryl during the later crop cycle if the cucumber beetle or squash bug reach their economic threshold in the insecticide control. Note: the insecticide product and treatment plan may change depending on pest populations encountered during trials. It is worth noting that insecticides are generally not effective in controlling squash vine borers.Objective 4 (Research/Extension). Establish demonstration/research plots in different farmer fields and at the UMES Research Education & Extension Farm to evaluate and showcase the best trap crop treatment as determined from objectives 1,2 and 3. On-farm trap crop research demonstration: Research/demonstrations of the most promising trap crop system will be established on three commercial and one university farm and evaluated for their potential to reduce cucumber beetle, squash bug and vine borer damage. The three commercial farm sites will include one site in southern DE, MD Eastern Shore and VA Eastern Shore. Each of the four farm sites will serve as a replicate and consist of a trap crop and a non-trap crop control treatment plot. Plot sizes will be ~ 15 m x 15 m with a 0.9 m intra- and 1.5 m interrow spacing, surrounded by one row of the trap crop. The trap and control plot treatments will be separated by a fallow area of at least 18 m to maintain treatment integrity. The trap crop will be treated with a systemic insecticide such as Imidacloprid or thiamethoxam at planting to prevent its destruction and movement of pests into the main crop. Further, treating the trap crop with systemic insecticides can increase its efficacy against cucumber beetles and squash bugs [17] and systemic insecticides provide traps crops better protection from decimation by beetles than foliar insecticides [65].