Upgrading of strawberry varieties
Vissers Aardbeiplanten BV has been spending time and energy for quite some years now on an upgrading programme, attempting to find new varieties, which are interesting for professional nurserymen. However, the upgrading of strawberry varieties is a time-consuming activity. First the father and mother should be determined on the basis of a profile. This profile depends on a list of wishes, which one should like to come back in the new variety.The items that are considered here include picking time, fruit characteristics, sensitivity to diseases, etc. A cross-fertilization is made and the pollinatedplants are planted separately from other ones, whereas any pollination by strange varieties should be avoided. The seed of the pollinated fruit will be sowed and each separate plant will represent a new variety. These seedlings should be bedded out and subsequently selected intensively. The real art is to distinguish the good ones from the bad ones. Subsequently, the selected seedlings will be increased and assessed again. In this way only the good plants will remain. It often occurs that none of the seedlings can stand thetest of criticism. The whole research path will take at least 10 years and yet it happens that a selected variety is not so good as it was expected to be. Throughout the years it is a question of coming and going of different varieties. In the listing of varieties some of the strains introduced by Vissers Aardbeiplanten BV are described. There are continuously new strains, which fit in with the profile of the variety in question and which are graded, partly in our company itself and partly by growers.
The most important properties for which a new variety is selected first of all, include:
- Appearance and taste of the fruit;
- Sensitivity to mould diseases;
- Deviating plant properties, like short flower stems, poor growth, etc.
- Yield potential;
- Firmness of the fruit and shelf life.
Subsequently the varieties selected are tested for their possibilities in different cultivation systems, for example very early cultivation in a glasshouse and sixty day crop with waiting bed plants, reckoning with the different climates in Europe.
Our range of strawberry varieties offers a wide selection for almost every commercial grower. We have varieties for late as well as early crops, for optimal flavor, optimal yield, or even both.
Our strawberry varieties have also been included in a maturity time overview, where you can easily compare times of maturity.
For a number of years now, Vissers Aardbeiplanten BV has invested time and energy in a breeding programme in an attempt to find new varieties that are interesting for the commercial grower.
The best strawberry plants will not achieve their full potential without a good cultivation system.
Strawberry plants are susceptible to threat from various pests and diseases. A number of precautionary and protective measures are required in order to achieve maximum production.
Strawberry plants are classified as follows:
- Pre-basic material (PBM) - This plant is registered at the Netherlands Inspection Service for Horticulture (NAKT) and has been tested for the absence of viruses. The propagating material obtained from candidate plants is classified as BM.
- Basic material (BM 1, 2 or 3) - These plants are propagated in an aphid-proof greenhouse. The first generation of propagating material is BM1. As long as these plants are raised in an aphid-proof greenhouse, the stock they produce will be classified as BM2. The stock produce by BM2 will be classified as BM3 ans is propagated in an aphid-proof greenhouse. If the generation of BM1 or BM2 or BM3 is raised outdoors, in these circumstances BM5-plants are produced.
- BM4 - The generation BM1 or BM2 or BM3, which are propagated in greenhouses, are suitable for propagation.
- BM5 - The generation BM1, 2, 3 or 4 suitable for propagation
- Certified material (CM) - Propagating material, obtained from BM certified mother plants.
CAC - Non-certified production plants, therefore not suitable for propagation purposes. The reasons for certification not being granted may be the foreign origin of mother plants, proximity of production fields or a too high percentage of plants with deviating traits.
The text above is derived from the guidelines set up by the NAKT in the Netherlands.Outside the Netherlands apply the same classification less stringent growth conditions.
Apart from its own breeding program Vissers Aardbeiplanten is also an initiator and participant in "Hansabred GmbH & Co KG", and share holder of the East Malling Breeding Club in England. Hansabred is a new breeding program me in Dresden, Germany, where Dr. Klaus Olbricht and his team breeds varieties of strawberries. EMBC at East Malling is breeding strawberries for many years and have been able to produce varieties like Elegance and Malling Centenary. Breeder is Dr. Adem Whitehouse and his team.