G.A. Abubakar, B.O. Ocheni, A.I. Gabasawa 1Department of Soil Science and Land Resources Management, Faculty of Agriculture, Usmanu Danfodiyo University, Sokoto, Nigeria 2Department of Soil Science, Institute for Agricultural Research, Faculty of Agriculture, Ahmadu Bello University,

S. Masheva, N. Valchev, V. Yankova Abstract. The experiment was conducted in 2007 and 2008 with leek variety Starozagorski 72. Single treatment with biostimulator Aveikan® was performed (2,5 L/ha) in phase 6-7 leaf of the crop and threefold in seedlings phase, one week after transplan