J. Robinson et M. Jalli, GRAIN-YIELD, NET BLOTCH AND SCALD OF BARLEY IN FINNISH OFFICIAL VARIETY TRIALS, Agricultural and food science in Finland, 6(5-6), 1997, pp. 399-408
Data on grain yield, and terminal severity of net blotch (Pyrenophora
teres f. teres) and scald (Rhynchosporium secalis) from Finnish offici
al barley (Hordeum vulgare) variety trials were analysed to indicate t
he pattern of disease incidence over six years and five sites for nine
teen barley genotypes, and the effect of the diseases on yield and the
genotype by environment interaction for yield. The effect of climatic
factors on net blotch severity were also investigated. The genotype b
y site interaction for net blotch severity was not statistically signi
ficant, but that for yield was. Net blotch severity differed between y
ears, but was similar across sites and there were statistically signif
icant first order interactions between year, site and genotype. 'Saana
' and 'Thule' had relatively low mean terminal net blotch scores and t
heir reaction to the disease was less sensitive to the environment tha
n was that of 'Tyra' for example. Analysis of yield data adjusted for
net blotch severity indicated that the magnitude of the genotype by en
vironment interaction terms were not accounted for to any significant
degree by differences in relative net blotch resistances among the bar
ley genotypes. Overall, mean scores for scald severity were lower than
those for net blotch. Terminal net blotch severity was correlated wit
h May rainfall and growing degree days.