New varieties are the lifeblood of strawberry production. Yet while there has never been such a wide range and number of good varieties on the market, it is still dominated by the Dutch-bred Elsanta, launched over 20 years ago.
Since it became established as the market leader, breeders throughout northern Europe have been trying to produce a variety to supersede it, but so far have not succeeded. However, Dr David Simpson – who runs East Malling Research’s (EMR’s) strawberry breeding programme – reckons he has hit the jackpot with Elegance (coded E1276), which is being evaluated in farm trials before its launch this autumn.
Simpson took over the programme in 1983 when it was transferred to East Malling from Long Ashton Research Station, where it was initiated in the mid-1970s by Don Wilson. Since then, he has produced more than 20 commercial varieties. The first was Pandora, introduced in 1988. Although it had very good fruit characteristics and yield potential, it had the disadvantage of being male-sterile and so required a pollinator.
A series of very good June-bearers (and everbearers) followed, notably Pegasus in 1992, Eros in 1994 and Florence in 1997. Florence was arguably the best because, apart from producing good yields of large, firm, sweet berries, it had the advantage of resistance to powdery mildew, Verticillium wilt and crown rot, and tolerance to vine weevil.
The trouble is that its flesh is deep red, which is perceived by supermarkets and consumers as a sign of over-ripeness and so it was never very popular in the UK. But that has not been the case in northern Europe, where it has been widely grown.
In 2005, four EMR varieties were launched including two very good everbearers, Malling Pearl and Malling Opal, and this year there have been three more – Sasha, Lucy and Fenella, all June-bearers – with Elegance to come. Judging by the high standard of the front-runners in the trials pipeline at EMR – viewed by growers at an open day held on 9 June – there will more coming over the next few years.
Change in funding
The future of the breeding programme was assured on 1 April 2008 (for the next five years, at least) when its funding underwent a big change. Its aims and modus operandi remain the same, though. Previously, Meiosis funded variety development and the Horticultural Development Company (HDC) funded all stages of variety trialling, with Defra paying for basic research. While Defra’s role remains unchanged, the main part of the programme is now funded by the Strawberry Breeding Club.
The club’s members pay an annual subscription that more or less equals Defra’s contribution. The membership includes EMR, the HDC, Meiosis, marketing groups KG Growers, Mack Multiples and Chingford Fruit, a number of UK propagators (associated with Meiosis) and nine Continental propagators operating as the European Strawberry Nurseries Association. This list is by no means final, though, because the club is seeking new members.
One aim of the Defra-funded work is investigation of the genetic characteristics contributing to good 60-day performance. That is one of the main advantages of Elsanta, so any replacement would need to be significantly better in that respect.
“In the past quite a lot of varieties from our programme and others in northern Europe have not always performed well as 60-day plants,” admits Simpson. “So we decided to look into why in some detail so that we can breed for better 60-day performance more successfully.
“It’s clearly important to produce better varieties to compete more effectively against Elsanta and also do well under a range of different cropping systems such as tabletops,” he adds. “We are making good progress and the Defra funding will allow this to continue.”
Simpson explains that this funding is also enabling his team to look closely at the thermodormancy of everbearer variety flowers (it can significantly reduce yield after hot weather) and whether greater knowledge of the problem can lead to the development of breeding lines with greater resistance to it. Seedlings from the first crosses arising from this work have now been produced.
The basic objective of the main part of the breeding programme remains unchanged: to produce varieties that have advantages over existing ones. They must be well-adapted, productive, high-quality types covering a range of seasons and have good resistance to pests and diseases so that growers’ reliance on pesticides is reduced.
The fruit of new varieties must also be well displayed and of good size so that it is easily and quickly picked, which means relatively low picking costs, to counter increasing labour wage rates.
Desirable traits
Most of the crosses used in the programme are between different numbered lines, some of which are supplied by other European breeders. Some specific varieties are also involved including a number from an Italian programme. Although these may not perform well under UK conditions they have a number of desirable traits that can improve the performance and acceptability of new varieties.
“There’s no single variety that’s outstanding for crossing purposes,” says Simpson. “But Sonata is a good parent and we’ve also used Florence and Eros. Elsanta was never a good parent, though. We did use it quite a lot at one stage but it didn’t pass on its good characteristics.”
Abi Johnson, who together with Adam Whitehouse works with Simpson, says that only one or two of the 13,000 or so seedlings they produce each year prove to be of any value “so it’s a numbers game, really”. This season they have 8,000 to 9,000 June-bearer seedlings in preliminary on-site trials and 4,000 to 5,000 everbearers. The latter tend to be easier to assess because they fruit over a much longer season. During fruiting, June-bearer plants have to be looked at much more often – every week.
Johnson is surprised that Elsanta has lasted so long in view of the very good alternatives available but it has done so because of its good suitability for 60-day production and a wide range of growing systems, so it will be hard to replace, she predicted.
Although some of the EMR varieties promised to be Elsanta beaters, they fell down mainly on 60-day yield, says Simpson. But that is not the case with Elegance, a cross between two numbered seedlings. He says it is the first EMR variety to have really good 60-day potential, outyielding Elsanta by as much as 40 per cent in early trials.
The variety has very good all-round fruit quality, producing very attractive, uniform, firm berries of good colour and skin strength. It also has a consistently high Class 1 gradeout, “usually in the low 90s (percentage) compared with 75 to 85 per cent for Elsanta”. And thanks to its large berry size it has a high picking rate.
The picking season for Elegance is slightly later than Elsanta’s but its plant habit is taller, more vigorous and erect. It is moderately resistant to Verticillium wilt but susceptible to powdery mildew and crown rot. For growers wanting to try the variety next season, plants will be available from Berryplants, Hargreaves Plants, RW Walpole & Partners and Welsh Fruit Stocks.
Whether or not Elegance lives up to its early promise will be established this season in more or less countrywide farm trials. About 50,000 runners have been planted – enough for around 1.5ha – under a range of different systems. The plants were available through Meiosis, which held an open day to promote the variety. Growers attending the event who were willing to carry out small-scale trials were allocated plants. The fruit will be test-marketed this summer.
At the breeding club’s open day, growers saw the first selections produced with club funding, together with some from the previous regime. The plants were grown from misted tips and planted in August last year. Picking of the earlier cropping selections began in late May and fruit from the more promising ones was taste-tested by the visitors against Elsanta. They recorded their scores for each of these for eating quality traits such as berry firmness, flavour and sweetness and the results will be used to help decide which selections will be trialled on farms next year.
“Only club members will be offered plants for trialling (off site),” explains Simpson. “They decide what selections they want and what trials they want to do, and they fund the trials themselves. The main advantage of club membership is that they get early sight (and experience) of potential winners.”
