Effects of the weed density on grass yield of Alfalfa (<i>Medicago sativa</i> L.) in different row spacing applications

Abstract

This study, in which the effects of different row spacing applications on weed density and on grass yield of Medicago sativa L. were investigated, was carried out in Van-Turkey from 2006 - 2008. Randomized blocks design was adopted with three replications. Row spacing applications of 20, 30, 40, 50, 60 and 70 cm were tested. The alfalfa plant height, yield of green herbage yield, dry matter yield, crude protein rate and crude protein yield were investigated. In addition, the weed densities at different row spacing distances were determined. The highest plant heights were obtained in 40 cm row spacing application in the first year and in 20 cm row spacing application in the second year. The highest dry matter and crude protein yields were obtained in 20, 30 and 40 cm row spacings in the first year and in 20 cm row spacing applications in the second year. The most intense weed was Alopecurus myosuroides Huds in 2007 and Amaranthus retroflexus L. in 2008. The least weed density was found in 20 cm row spacing during all three before cutting periods in the first year of study and this was found in 30 cm row spacing application in first before cutting period and in 20 cm row spacing application in the second and third before cutting periods in the second year.

Key words: Alfalfa, weed, row distance, yield.