Influence of sowing depth paraquat herbicide and solarization on seed germination of some winter and summer weeds

ABSTRACT

Two experiments were conducted in pots in 1998 and 1999 seasons to determinethe influence of seed depth on seedling emergence of wild oat, burcloverand pig weed with and without paraquat; seed depth and soil solarization onseed germination of purslane, field sandbur and jimson weed. Results of thefirst experiment showed that increasing sowing depth from 1 to 12 cm reducedgermination rate percentage after 6 weeks from sowing by 54.0 and 48.3 forwild, 51.5 and 59.0 for burclover, and 65 and 58.5 for pigweed in 1998 and1999 seasons, respectively. The germination rate of wild oat and burcloverwas higher than pigweed. Increasing depth from 1 to 12 cm plus paraquat[0.200 kg a.i./fed.] application significantly decreased germinationpercentage as compared with control. The highest reduction was clear inpigweed after three weeks from sowing. Results of 2nd experiment indicated thatgermination rate of purslane was higher than field sandbur and jimson weedafter three weeks of sowing at 1 cm depth. Purslane field sandbur and jimson seeddid not germinate at 1 and 3 cm depth + solarized treatments after three and sixweeks from sowing in both seasons