Competition Effects of Fat-hen (Chenopodium album L.) and Groundsel (Senesio vulgaris L.) on cabbage and lettuce.
2003
Qasem, J. | Hill, T (London Univ., London (UK))
Competition effects of fat-hen (Chenopodium album L.) and groundsel (Senecio vulgaris L.) on cabbage (Brassica oleracea L. var. Capitata) and lettuce (Lactuca sativa L.) were investigated under glasshouse conditions. Weed competition significantly reduced growth of both crops and lowered their accumulation from nitrogen, potassium, phosphorus, calcium and magnesium. Crops were different in their accumulation of different mineral elements. . while cabbage had greater calcium concentration in shoots, lettuce showed higher tissue concentration of potassium. Considering potassium accumulation, cabbage showed higher competition index and relative competitive ability index with weeds than lettuce but differences between crops were lower based on tissue accumulation of calcium. On the other hand, concentrations of all minerals in shoots of both weeds were significantly reduced in competition compared with their concentrations in pure stands. More reduction was obtained in competition with cabbage than with lettuce. C.album showed higher concentrations of potassium and magnesium than S.vulgaris. Competition index and relative competitive ability index indicate that C. album competes better than S.vulgaris at high potassium and S.vulgaris is better at high level of calcium in the growing medium.
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