Effect of leaf spotting diseases on grain yield and seed traits of wheat in southern Saskatchewan

Abstract

. 2002. Effect of leaf spotting diseases on grain yield and seed traits of wheat in southern Saskatchewan. Can. J. Plant Sci. 82: 507-512. Although leaf spotting diseases have been reported to have a negative effect on grain yield and seed characteristics of wheat (Triticum spp.), the magnitude of such effects on wheat grown on dryland in southern Saskatchewan is not known. A fungicide experiment was conducted at Swift Current (Brown soil) and Indian Head (Black soil) from 1997 to 1999 to determine the effect of leaf spotting diseases on yield and seed traits of wheat. Two fungicides, Folicur 3.6F and Bravo 500, were applied at different growth stages on three common wheat (Triticum aestivum L.) and three durum wheat (T. turgidum L. var durum) genotypes. Fungicide treatments generally did not affect yield, kernel weight, test weight or grain protein concentration, and these effects were relatively consistent among genotypes. Folicur applied at head emergence in 1997 and at flag leaf emergence and/or head emergence in 1998 increased yield at Indian Head (P < 0.05). Fungicides applied at and before flag leaf emergence tended to increase kernel weight. Grain protein concentration increased only in treatments of Bravo applications at Indian Head in 1998. These results suggested that under the dryland environment and management in southern Saskatchewan leaf spotting diseases generally have a small effect on yield, kernel weight, test weight and protein concentration.

Assessing Effects of Climatic Change, Region and Agronomic Practices on Leaf Spotting of Bread and Durum Wheat in the Western Canadian Prairies, from 2001 to 2012

“…The PLS analysis was performed using the PROC PLS procedure of SAS (SAS Institute, 2013;Tobias, 1995). Predictors with the greatest influence in explaining LS severity and percentage isolation were selected based on the criterion of variable importance in the projection (VIP) > 0.8 (Wold, 1995) and the size of the standardized PLS regression coefficient (coefficients near to or greater than or about 0.07 or less than or about -0.07). Important predictors were considered for further analysis (i.e., analysis of variance).…”

“…In most cases, differences among locations and years were reported, in addition to impacts of agronomic practices, including cultivar, not only on disease levels but also on the relative prevalence of the pathogens. Replicated plot studies on LS of wheat were done in the 1980s and 1990s in southern Saskatchewan at Indian Head in the Black soil zone (Bailey et al, 1992(Bailey et al, , 2000(Bailey et al, , 2001, Swift Current in the Brown soil zone (Fernandez et al, 1998b(Fernandez et al, , 1999, and both these locations (Wang et al, 2002). These studies reported some significant, and sometimes conflicting, effects of agronomic practices on the LS complex.…”

Impacts of agronomic practices on the leaf spotting complex of common wheat in eastern Saskatchewan

“…Impacts of LS on grain productivity can vary greatly among years and locations and may be less limiting to grain yield and quality than abiotic stresses (Wang et al 2002). Eyal (1972), Bockus et al (1997) and Bhathal et al (2003) showed that infection of wheat by Ptr and the septoria leaf blotch fungi caused significant yield losses in Israel, northern Great Plains, USA, and, western Australia respectively.…”

Quantification of effects of leaf spotting diseases on grain yield and market quality of durum wheat using near-isogenic lines

“…Further, some fungicide effects have been reported as not being directly related to the control of leaf diseases in winter and spring hexaploid and durum wheat (Fehrmann et al, 1978;Wang et al, 2002). Interactions with environmental conditions and plant development make fungicides an unreliable tool to assess the effect of LS on crop performance by potentially having effects on plant growth and yield not directly related to disease control.…”