[Competitiveness of hard wheat (Triticum durum Desf.) varieties against ripgut brome (Bromus rigidus Roth)]

Varieties with an excellent competitiveness against ripgut brome (Bromus rigidus Roth.) would be very important to reinforce others methods to control ripgut brome weed. This study was carried out in 1999-2000 season in a greenhouse experiment to test the aggressiveness degree of six varieties of hard wheat (Oum Rabia, Isly, Marzak, Karim, Sebou, and Massa) combined with ripgut brome. Plant density was fixed at 16 plants of wheat or Bromus for pure crop and 8 plants for wheat and 8 for Bromus mixture. The results showed that the numbers of kernels/spikes were higher in the mixture for on pure composition. For the kernel weight, the result was opposite except for Isly and Marzak varieties. Karim and Isly varieties obtained the highest grain yield and were more competitive in mixture composition but Sebou and Massa varieties were less competitive against ripgut brome. Results of ripgut brome productivity and water use efficiency were similar and were used to determine the aggressiveness coefficient of hard wheat varieties against ripgut brome. The reduction of the shoot dry matter of brome was 22 to 56% at flowering. The grain yield of brome was reduced from 57 to 81%.