Influence of Date of Planting on the Growth of Yellow Nutsedge (Cyperus esculentus)

Abstract

Plants produced by yellow nutsedge (Cyperus esculentusL. # CYPES) tubers planted in a field at the U.S. Cotton Research Station, Shafter, CA, at monthly intervals were harvested 2, 4, or 8 weeks after planting or at the end of a full season that varied from 12 to 37 weeks. In the 2 yr of the study, 1982 and 1983, tubers were slow to sprout in March and April, taking up to 8 weeks. From June through October about 60% of the plants emerged within 2 weeks of the planting date. Parent plants produced daughter plants by the 4-week harvest except for March, April, and October 1982, and March 1983 planting periods. All planting periods had daughter plants by the 8-week harvest. In 1982, plants of the June full-season planting had significantly more daughter plants than plants of other full-season treatments even though the June full season was 12 weeks shorter than the March full season. In 1983, the number of daughter plants produced by plants for the full-season harvest was equal for all monthly plantings regardless of the length of the full season. In 1982, for the May through September plantings, more tubers were produced by plants at the 8-week harvest than the number of tubers originally planted. In 1983, only plants of the June and August plantings produced more tubers by the 8-week harvest than had been planted. In both years, plants that grew for a full season produced more tubers than the number planted, up to 200-fold more.