The effect of ryegrass (Lolium italicum L.) stand densities on its competitive interaction with cleavers (Galium aparine L.)

Authors : Sava VRBNICANIN, Mirjana KRESOVIC, Dragana BOZIC, Aleksandar SIMIC, Radojka MALETIC, Ahmet ULUDAĞ

Pages : 121-131

Doi:10.3906/sag-1207-67

View : 19 | Download : 10

Publication Date : 2012-02-01

Article Type : Research Paper

Abstract :Italian ryegrass insert ignore into journalissuearticles values(Lolium italicum L. cv. Tetraflorum); seed production is an important industrial activity in Serbia. Cleavers insert ignore into journalissuearticles values(Galium aparine L.); interferes in Italian ryegrass seed production as well as in many other crops. The effect of stand density of Italian ryegrass on its competitive interaction with cleavers was investigated in western Serbia in the 2005-2006 and 2006-2007 cropping seasons. The established density treatments of Italian ryegrass were 5 kg ha-1 seeding rate with 60 cm row spacing insert ignore into journalissuearticles values(SD1);, 5 kg ha-1 with 20 cm insert ignore into journalissuearticles values(SD2);, 20 kg ha-1 with 60 cm insert ignore into journalissuearticles values(SD3);, and 20 kg ha-1 with 20 cm insert ignore into journalissuearticles values(SD4);. The interaction between Italian ryegrass and cleavers was evaluated by SPAD reading, relative nitrogen content insert ignore into journalissuearticles values(RNC); in the leaf, total nitrogen content insert ignore into journalissuearticles values(TNC); in the leaf, and seed yield. The rank order of the competitive ability of Italian ryegrass was SD4 > SD3 > SD2 > SD1 under optimal weather conditions for crop development. Under climatic stress conditions, however, neither effect of ryegrass densities nor cleavers was pronounced on competitive ability of ryegrass with different stands.
Keywords : Key words Relative nitrogen content RNC, in the leaf, SPAD reading, total nitrogen content TNC,