New Grape Cultivar ‘Grosz Krone’

Abstract

‘Grosz Krone’ is a tetraploid table grape cultivar with purplish black skin, resulted from a cross of ‘Fujiminori’ and ‘Aki Queen’ made in 1998. The original vine of ‘Grosz Krone’ was initially selected in 2002 in a vineyard at Akitsu, and was tested as selection Budou Akitsu 30 under the 13th Grape Selection National Trial initiated in 2010. It was released as ‘Grosz Krone’ in 2017, then registered as No. 28086 under The Plant Variety and Seedling Act of Japan in 2020. The vine vigor is strong. Sprouting and flowering times are 1 day and 2 days later than ‘Kyoho’ in the national trial. Time taken to trim flower clusters was the same as ‘Kyoho’, but that to trim berries is shorter than ‘Kyoho’. Harvest time of seedless fruit is the same as ‘Kyoho’ but 4 days earlier than ‘Pione’. Berry weight averages 19 g, larger than ‘Kyoho’ and ‘Pione’ in seedless fruit production. Soluble solids concentration averages around 18.4 %, similar to those of ‘Kyoho’ and ‘Pione’. Titratable acidity averages 0.46 g/100 ml, significantly lower than that of ‘Kyoho’. Flavor is foxy. Berry skin cracking sometimes occurs depending on years and locations. Seedless berries can be produced by GA treatment, but streptomycin treatment before anthesis is needed for complete convert to seedless berries. Berry skin color is attractive purplish black. Berry skin shows good coloration compared to ‘Kyoho’ and ‘Pione’ even in warm region of south west districts in Japan. Therefore, ‘Grosz Krone’ is expected to be a suitable cultivar for adapting to warmer climate. Summary