Effects of sowing time on pink snow mould, leaf rust and winter damage in winter rye varieties in Finland

Abstract

Disease infection in relation to sowing time of winter rye (Secale cereale) was studied in southern Finland in order to compare overwintering capacity of modern rye varieties and to give recommendations for rye cultivation. This was done by using three sowing times and four rye varieties in field trials conducted at three locations in 1999-2001. The early sown rye (beginning of August) was severely affected by diseases caused by Puccinia recondita and Microdochium nivale, whereas postponing sowing for two weeks after the recommended sowing time resulted in considerably less infection. The infection levels of diseases differed among rye varieties. Finnish rye varieties Anna and Bor 7068 were more resistant to snow mould and more winter hardy than the Polish variety Amilo, or the German hybrid varieties Picasso and Esprit. However, Amilo was the most resistant to leaf rust. In the first year snow mould appeared to be the primary cause of winter damage, but in the second year the winter damage was positively correlated with leaf rust. No significant correlation between frit fly infestation and winter damage or disease incidence of snow mould or leaf rust was established. The late sowing of rye (in the beginning of September) is recommended in Finland, particularly with hybrid varieties, to minimize the need for chemical plant protection in autumn.

Climate change and prolongation of growing season: changes in regional potential for field crop production in Finland

“…Winters in the south-westernmost parts of Finland would be similar to those in Denmark. Although numerous factors affect success of overwintering capacity of field crops (Hömmö and Pulli 1993, Lindén et al 1999, Hofgaard et al 2003, Serenius et al 2005, Velicka et al 2006, considering mildness of winters only as a reduction in numbers of frost days, we can estimate the potential time-frame for introduction of currently grown autumn sown crops over a larger extent and introduction of novel overwintering crop species. For example, cultivation of winter wheat, currently grown only in restricted areas of southern Finland where there are about 130 frost days at most, can be extended to the Oulu region by end of this century in the A2 scenario (Fig.…”

Pests and diseases in a changing climate a major challenge for Finnish crop production

“…This could result in reduced resistance against pathogens and weakened growth early in the season, when reserve carbohydrates are required for growth and maintenance of the photosynthesising leaves (Hakala and Pahkala 2003). Long and warm autumns could also lead to reduced cold hardening (Bélanger et al 2002) and too dense canopies that favour pathogens (Serenius et al 2005).…”

“…Also rusts, especially brown rust (Puccinia recondita Dietel & Holw), could become an increasing problem. Winter cereals can be attacked already in autumn, which can have detrimental effects for overwintering of crops (Serenius et al 2005). Climate warming can also have indirect effects by changing rust and powdery mildew resistance gene expression.…”

Sowing time affects the abundance of pests and weeds in winter rye

“…Furthermore, the study attempted to assess effects of sowing time on early crop development of four different rye varieties. The occurrence of leaf rust and the importance of snow mould as causal agents of winter damage were also investigated but the results has been reported separately (Serenius et al 2005).…”