Controlled studies further the development of practical guidelines to manage dodder (Cuscuta gronovii) in cranberry production with short-term flooding

Abstract

Flooding is an inexpensive cultural practice used for pest management in Massachusetts cranberry (Vaccinium macrocarpon Ait.) production. This project examined the use of short-term floods ( < 72 h) for dodder (Cuscuta gronovii Willd.) management under controlled conditions. Using incubators, seed was submerged in water for 0, 24 and 48 h at 10, 15 and 20 C (simulating spring water temperatures) and 0, 12, 24, 36 and 48 h at 15, 20 and 25 C (simulating summer water temperatures). Two 1-year controlled studies (field and greenhouse) evaluated three flood durations (0, 24 and 48 h) and four flood initiations (1, 2, 3 and 4 weeks after early seedling emergence (AEE)). Treated seeds were planted to cranberry vines and to Petri dishes; percent germination, degree of dodder attachment and dodder biomass data were collected. Treatments had limited effect on seed germination. Flooding 4 weeks AEE resulted in the lowest mean attachment ratings and dodder stem biomass on cranberry. This preliminary work provides evidence that flooding may retard dodder stem growth rather than reducing seed germination and that floods initiated after some time has elapsed after early emergence may be more effective than those initiated closer to the time of seedling emergence. More information is needed to thoroughly understand the processes involved; however, small projects such as this can provide interim guidelines that growers can immediately consider when deciding on a dodder management program.

Damage and Recovery of Cranberry Vines from Exposure to Handheld Flame Cultivators

“…Cuttings for 'Stevens' and 'Howes' were taken from established cranberry farms located in Wareham, MA. Cranberry plants were cut and rooted according to previously published protocols (O'Connell et al, 2011). During establishment (May through September), plants were fertilized once per week with 15N-7.0P-14.1K (833 mg • L -1 ) by drenching the soil with the fertilizer solution.…”

Mechanical Scarification of Dodder Seeds with a Handheld Rotary Tool

“…Glass covers were placed over dishes and sealed with Parafilm (Parafilm M, Pechiney Plastic Packaging, Menasha, WI 54952) strips to reduce evaporative water loss. Dishes were incubated (Fisher Low Temperature Incubator Model 307, Fisher Scientific) in the dark at 23 C and were checked periodically for 3 wk after scarification to evaluate seed germination (Benvenuti et al 2005;O'Connell et al 2011). Germinated seeds were removed from the dishes and counted, and the percentage of germination was calculated.…”

Weed Management in Cranberries: A Historical Perspective and a Look to the Future

“…Field studies indicated that 24-48 h floods in mid-May may offer a sustainable option that could be integrated into the overall management plan for dodder [15]. Subsequent work indicated that the floods may retard dodder stem growth rather than reduce seed germination [79].…”