Viability of Cyperus esculentus Seeds and Tubers After Ensiling, Digestion by Cattle, and Manure Storage

Cyperus esculentus is an invasive sedge causing high losses in many crops. Prevention is key in minimizing further spread and damage. Propagules (tubers or seeds) may spread via cattle manure. This study examined the effect of ensiling, digestion, and storage in manure on the viability of C. esculentus propagules. Propagules were subjected to five durations (0–16 weeks) in silage maize, seven durations (0–48 h) of ruminal digestion, and five durations of storage (0–16 weeks) in manure (slurry or farmyard), or combinations of previous processes. Afterwards, the viabilities were determined by a germination and tetrazolium test. After 6 weeks in a maize silo, the viability of the propagules was reduced by at least 96%. Incubation for 36 h in the rumen, followed by post-ruminal digestion in vitro, reduced seed viability by 30%. However, for the tubers, no effect was observed. The viability of seeds and tubers was reduced by 90% after 11.5 and 13.7 weeks of incubation in slurry, respectively. Compared with seeds, tubers were less tolerant to 12–24 h of animal digestion, followed by 8 weeks of storage in slurry. Keeping a maize silo closed for at least 6 weeks and maintaining slurry storage for at least 16 weeks are excellent measures to eliminate C. esculentus. For farmers, these preventive measures are relatively easy and cheap to implement compared to the requirements of curative control methods.