"VVA-1 most beneficial for moderately productive plum varieties" (EFM, Gerard Poldervaart + Frank Maas)

"Plum producers are awaiting trees on VVA-1 rootstocks. It will take until 2006 before these are available in abundance. Nevertheless, their patience will be rewarded, assures JACQUES Botden, General Manager of fruit tree nuseries Botden & van Willegen, the organization that holds the exclusive production and sales rights in EUROPE."
"The wait for VVA-1 is compensated for in production" "Fruitteelt" 27, July 2004, Volume 94

"Up until 2003, trees on VVA-1 would show the weakest growth, the richest flowering and yielded the highest production and the largest fruits."
"Research into VVA-1 Caroline van Assche" "Fruitteelt" 4, January 23, 2004

"At PPO, the plum trees fuse well on the VVA-1 rootstock. Production starts much earlier compared with the standard St Julien A rootstock or the Ferlenain and Pixy rootstocks. In the past years, the VVA-1 already yielded the highest production rates of these four, and the same is true for this year. As the trees on this rootstock grow at a calmer pace, they can also be planted much closer to one another." "restraining the growth of plum trees" Monthly magazine "NFO Circle Noord Hollland", November 2003

"The addition of the Russian rootstock by the name of "VVA-1" seems a great asset. So far, test results have proven highly positive. "VVA-1" produces a small tree, with early production and a good fruit size. "VVA-1" is described as hardy, with a weak growth, and compatible with plum, peach and apricot. This rootstock has good anchoring, few root suckers and is not sensitive to wet soil conditions."
"VVA-1 restrains the growth of plum trees" "De Boomkwekerij" 31/32, Augustus 3, 2003

"With respect to plum rootstocks, the Randwijk research really confirms what was known already: of all of the weak rootstocks that have so far been tested, VVA-1 clearly stands out as a winner. Its growth is evidently much weaker than that of St Julien A. Its production starts earlier and is higher, and the fruit size is not inferior to St Julien A. Moreover, trees on VVA-1 have a slightly different growth habit. The plum growers present assessed the trees on VVA-1 as "nicer, more open and easier to work with"."
"Search for stone fruit rootstocks continues" "Fruitteelt" 31, Augustus 1, 2003

"The test included the VVA-1 rootstock. This rootstock, with its weak vigour, allows for more intensive planting and a higher yield, partly because of the trees' earlier fruit-bearing."
"Growers' association Reine Victoria projects a high-profile image" "Fruitteelt" 27, July 4, 2003

"The VVA-1 rootstock probably offers more possibilities in this area. An old test by PPO, conducted at the site of the Hamelink company, also included VVA-1. Unfortunately most of the then four-year old trees did not make it in 1998, having had to deal with the flooding in September. However, in the remaining trees, the growth restraining effect is clearly visible. They are almost half the size and, moreover, yield very good productions."
"I specialize in plums - no one else will do it" 'Fruitteelt' 23, June 6, 2003

"VVA-1 yields a smaller and by all appearances more open tree compared to St Julien A. This rootstock, which has been the subject of empirical testing for seven years in Wilhelminadorp, shows no dying off or incompatibility."
"Search for rootstocks and production varieties for plums continues" "Fruitteelt" 31, August 3, 2001

"In conclusion one can say that VVA-1 seems a suitable rootstock for Dutch plum production. This weak rootstock deserves recommendation for use in practice on a limited scale. As is true for all weak rootstocks, VVA-1 requires more care in production and more attention to fertilization and watering than strong rootstocks."
"Good fusion of Opal on VVA-1 instils confidence" "Fruitteelt" 27, July 6, 2001

"The first order of Russian new, weak VVA-1 rootstocks will arrive from Russia in September through a Dutch nursery. The first results of Dutch research were favourable, and De Ruiter has reached a stage where something new is certainly welcome."
"Nothing is peculiar in plum production" "Fruitteelt" 34/35, August 1999

The wait for VVA-1 is compensated for in production.

It will take as long as until 2006 before they are available in abundance. Nevertheless, the wait will be rewarded, assures JACQUES Botden, General Manager of fruit tree nurseries Botden & van Willegen, the organization that holds the exclusive production and sales rights in EUROPE. The trees on VVA-1 that will be planted in 2006 will bear fruit earlier than those on St Julien A that will be planted this coming season, according to Botden.

In 1996, Jacques Botden, General Manager of fruit tree nurseries Botden & van Willegen, first learned of the new plum rootstock VVA-1.
Researcher Bob Wertheim had included the rootstock in a test with Opal in 1994, at the former Research Station for Fruit Production in Wilhelminadorp. In the annual report of 1996, he first reported that Opal showed weaker growth on VVA-1 compared to the other rootstocks. A few years later, he concluded that trees on the VVA-1 rootstock were smaller and more productive than trees on the St Julien A rootstock. VVA-1 originates from the fruit production research institute Krymsk in Russia. Professor Eremin of the same institute was responsible for the rootstock breeding.
"In the nineties, however, no one showed any interest in weak-growing plum rootstocks,' remembers Botden. 'Plum planting was hardly engaged in at the time. Stone fruit growers concentrated all of their efforts on cherry production with the new Gisela 5 rootstock."
This tree grower, however, did see possibilities for the weak-growing plum rootstock and departed for Russia to close test contracts with the licensee. And it worked. He was granted an opportunity to create a limited number of trees for practical testing.

Test results
The trees in Wilhelminadorp had to be uprooted after seven years due to the fact that the test garden was closed down. During those seven years, none of the trees had died as a result of incompatibility. Following the testing in Wilhelminadorp, VVA-1 has also been tested since 1997 in the test garden of PPO-fruit in Randwijk, using different varieties: Excalibur and Avalon. The results are similar to those obtained in Wilhelminadorp. Every time, VVA-1 produced the smallest trees with the highest production rates and a good fruit size.
However, production on VVA-1 does require extra attention to fertilization as the magnesium and manganese contents are lower than in St Julien A.
Later on, more tests were conducted using Victoria. Again, these tests yielded only positive results: up until 2003, VVA-1 showed the weakest growth, with the richest flowering, yielding the highest production rates and the biggest fruits. The weak rootstock does not, however, seem to be able to prevent the formation of gum, to which Victoria is prone.

Growing takes time
As the word spread on the favourable test results with VVA-1, more and more fruit growers wanted to have plum trees on this rootstock. Preferably without delay. 'But it does not work that fast,' explains Botden. 'The Russian professor had protected the rights world-wide. Under the testing contract, we were not allowed to produce trees on a large scale. Since last year, we have been able to secure the exclusive production and sales rights for Europe. This means that we are the first and only fruit tree nursery in EUROPE who is allowed to create trees on VVA-1,' Botden informs us with pride. 'Growing takes time. Last year we created a few hundred trees. They struck root beautifully. The production with trees on VVA-1 is not harder than on St Julien A,' observes the tree grower.
'As with St Julien A, chip budding works best. The first trees were delivered this past season to two growers who stuck out their necks a few years ago and participated in the practical tests,' recounts Botden.
This year, the station accommodates a few thousand trees, which will become available in the coming autumn. 'We deliver according to the order of receipt of orders. Next year, we will be able to create as many trees as are ordered, so for the autumn of 2006 we will probably have sufficient trees available to meet the demand. At this point in time, we cannot create more trees, simply because we do not have a matching supply of rootstocks,' explains Botden. 'We have planted mother trees, but we need to wait for them to reach their productive stage. Eight years ago, no one had yet heard of VVA-1. It is quite an achievement in itself that we are already able to grow trees on this rootstock,' says Botden. The price of the trees on VVA-1 will be approximately 25% higher than the price of trees on St Julien A.

Virus testing
VVA-1 is not yet certified as being virus-free. This does not mean, however, that the trees we are making now contain any viral disease, as Botden explains. Naktuinbouw (the Netherlands Inspection Service for Horticulture) is currently busy testing the new rootstock for viruses. The rootstock has already passed the first test for the most important viruses successfully. These harmful viruses were not detected. The testing will continue for a number of years. If the findings of Naktuinbouw remain positive, the rootstock will be certified as virus-free in three to five years' time.

At this point in time, Botden does not yet receive many applications for trees on the VVA-1 rootstock from abroad. Outside the Netherlands, this rootstock is not very well known yet. 'Apart from this, we have not yet engaged in extensive promotion campaigns. After all, we cannot yet deliver them.' Nevertheless, Botden expects the demand to grow in time, especially from an important plum production country like Germany. 'And in the future, we plan to grant sublicences, so that more tree growers will be able to create trees on VVA-1.'

Caroline van Assche