Contribution of pre-anthesis assimilates to grain yield and nitrogen content in spring barley

Abstract

Growing kernel of barley (Hordeum vulgare L.) can be supplied with carbohydrate and nitrogen (N) from current assimilation or from translocation of pre-anthesis accumulated reserves, which are stored in the vegetative plant parts. This study was conducted to assess the contribution of pre-anthesis accumulated dry matter and N to grain yield and N content in spring barley. Eight spring barley cultivars, originated from semiarid (Pek, Jelcn, Schooner, Cantala) or moderately humid conditions of growing (KM 184, Orbit, Triumph, Gimpel) were grown on a non-calcareous chernozem soil in three growing seasons (1995-1997) at Novi Sad (45 degrees 20' N, 15 degrees 51' E, 86 m asl) at two N levels. Pre-anthesis dry matter contributed to total dry matter at anthesis 44, 33, and 31% in 1995, 1996, and 1997, respectively, Dry matter translocation occurred only in favorable growing conditions. The cultivars did not differ in vegetative dry matter at anthesis and maturity and yield. N accumulated at pre-anthesis represented 92, 68, and 51% at the low N level and 138, 76, and 54% of total N at maturity at the high N level in 1995, 1996, and 1997, respectively. Depending on the year and N level, translocated N across cultivars represented 34-171% of grain N. Nitrogen losses occurred when anthesis N exceeded 150 kg.ha(-1). Selection of genotypes with a higher ability of pre-anthesis reserve utilization or genotypes with efficient post-anthesis dry matter and N accumulation may be two possible solutions in spring barley breeding for semiarid growing conditions.