Autumn Fruiting Raspberries: keeping up with the Joans
Derek Jennings, the well known raspberry breeder responsible for all the Glen varieties which were named after the Scottish Glens that Derek had walked, describes his more recent successes produced during his 'retirement' in Kent.
After years of breeding summer-fruiting raspberries in Scotland it was difficult for me to give up the job when I `retired`. So I formed a partnership with a leading Kent fruit grower and, since I needed a change, took up the breeding of the autumn-fruiting kind. At this time autumn-fruiting, i.e.primocane-fruiting, raspberries; were only just beginning to become popular. Autumn Bliss, launched by East Malling in 1983, was a big advance in earliness and fruit size, but to many growers autumn-fruiting still meant old varieties like Heritage, Zeva or September Red, which either crop late or have poor fruit qualities. A broadening of the gene base was needed and the obvious way to achieve it was to transfer genes from the summer-fruiting kinds. This approach tends to lead to late cropping, and so breeders worldwide were making much use of Autumn Bliss. My Australian collaborator, for example, had success with the cross Autumn Bliss x Glen Moy. Varieties like Glen Moy and several of my best summer-fruiting selections produce a very late autumn crop as well and I began crossing the best of them with the earliest available autumn-croppers.
Another change was that I could name my varieties after the ladies in the family rather than after Scottish Glens. My first success was Joan Squire. It can be described as a second early and its fruit suited most but not all market outlets. It came from a cross between my Australian collaborator`s selection and the unnamed summer-fruiting selection mentioned. It became a leading variety whose use peaked in 2002 and is now declining in the face of competition from newer varieties. Growers in Chile who export raspberries over long distances to North America reported that it was not quite good enough for this purpose, so I sent them my selection 941/3 from a cross between Joan Squire and Autumn Bliss, just for them to test how it traveled over long distances. The selection has many faults and I asked them not to report them because I know them all!
To my great surprise they think 941/3 is perfect and last year reported a production of 338 tons of it. I cannot visualise what 338 tons of raspberries look like. Maybe a small mountain? The person who promoted it in Chile is Marcela Zuniga so I named it Marcela in appreciation. It is so early that under the warm growing conditions of Chile and Mexico it gives two primocane crops a year. But we are still too concerned about its short comings to launch it in the UK.
A selection that came from my own cross between Autumn Bliss and Glen Moy is Terri-Louise. It has exceptional fruit size but poor shelf-life and was more useful as a parent than for commercial use. Crossing it with Joan Squire gave me Joan J. Joan J. clearly illustrates the different priorities of the supermarkets and the consumers. Its very excellent size and flavour make it a clear favourite with consumers as shown by big sales of plants to amateur gardeners and to non-supermarket suppliers. Thus recent annual sales have been 76,000 plants in the UK and 67,000in the USA. But the supermarkets feel that its slight tendency to darken when very ripe and a slightly weak skin strength reduce its shelf-life and they have all refused to accept it.
In parallel with Joan J. we have Joan Irene (the same Joan using her middle name). This came from a progeny of Joan J. and has been less successful, though it surprised us by attaining popularity in Chile for its early summer crop. No doubt it is a mistake not to assess autumn fruiters for their summer crops as well or, more importantly, for `double` cropping, i.e.an autumn crop at the tips of the first years` canes followed by a summer crop from the basal parts of the overwintered canes.Joan Squire responds well to this, giving an annual yield almost double that of its autumn crop alone. Unfortunately, the fruit size of the summer crop tends to be one third less than that of the autumn crop and can be unacceptably small. Joan Irene, with larger autumn fruits, is better equipped for the practice.
More recently, the cross Joan Irene x Marcela gave the selection 13/10, which last year shared first place at the National Fruit Show with one of Peter Vinson`s selections. Watch this space!
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