FUNGI FOR BIOLOGICAL CONTROL OF WEEDY CYPERACEAE, WITH EMPHASIS ON PURPLE AND YELLOW NUTSEDGES (CYPERUS ROTUNDUS AND C ESCULENTUS)

摘要

Purple and yellow nutsedges (Cyperus rotundas and C. esculentus) are widely distributed weeds in many tropical and subtropical regions of the world. Nutsedge management is difficult partly because of their ability to produce numerous tubers that sprout readily and produce more tuber a few weeks after sprouting, thus perpetuating the weed. These weeds are generally considered among the worst weeds (Doll, 2000; Holm et al., 1991), particularly in vegetable crops, for which the availability of selectivechemical herbicides is very limited or completely lacking. Purple nutsedge is more commonly found in irrigated, warm regions, whereas yellow nutsedge is predominant in wet and/or cool environments. However, both species may coexist in subtropical regions such as northern Mexico and the southern USA.