SUSCEPTIBILITY OF ‘OTTAWA’ AND ‘MUSKOKA’ RASPBERRIES TO CANE MIDGE (RESSELIELLA THEOBALDI)

The susceptibility of ‘Ottawa’ and ‘Muskoka’, which are the most widely cultivated red raspberry varieties in Finland, to cane midge (Resseliella theobaldi (Barnes)) and midge blight was examined in 1980–82. In autumn, the first-year canes of ‘Ottawa’ were more infested by midge larvae than the canes of ‘Muskoka’. In June and July the fruiting canes of ‘Ottawa’ were also infested.
There was a positive correlation between the numbers of larvae and fungal lesions on the first-year canes of ‘Ottawa’, but not between those on ‘Muskoka’.

Before harvesting the fruiting canes of ‘Ottawa’ were killed more frequently by midge blight than those of ‘Muskoka’. The yield of ‘Muskoka’ was twice that of ‘Ottawa’

Natural splits in the first-year canes of both varieties were first observed at the same time at the end of June, but ‘Ottawa’ split more.
The canes of ‘Ottawa’ were thicker than those of ‘Muskoka’ in September.
There was a positive correlation between cane diameter and the number of larvae but not between cane diameter and the number of fungal lesions.

IV International Rubus and Ribes Symposium

P. Dalman

https://doi.org/10.17660/ActaHortic.1986.183.16