b'global breeding lead, Syngenta. Probably the type with more market segments and variation for plant adaptability is the Beit Alpha type, and therefore, the number of prototypes that we have to create is higher. Different from other crops, the spec-ificity of fruit quality is so high that there are few chances to share breeding programs, so that there is one specific program for every type.In our cucumber breeding programmes, we mainly focus on long cucumber and mini-cucumber. We develop new vari-eties with combinations of important traits, adapted to local circumstances with added value to our customers: both for the grower, industry and consumer, says Eric Bal, breeding man-ager cucumber, Rijk Zwaan. Since its establishment in 1991, Moravo Seed has expanded its product range to include more than 435 varieties of vegeta-bles, says Radek Aust, executive manager, Moravo Seed. In the actual assortment there are 23 varieties of gherkins cucumber, 10 varieties of greenhouse cucumbers with different fruit lengths and five American slicer-type cucumbers. We have a growing share of parthenocarpic types with multifruit effect of gherkins. Greenhouse cucumbers are rep-resented from the smallest size of fruits with 10 cm up to 40 cm. The largest proportion of breeding work therefore falls on gherkins and greenhouse cucumbers, he adds. FOCUS ON CUCUMBER TYPEWe currently have breeding programs for Dutch, Beit Alpha pickling and slicing typologies. We also have a program for spe-cial types such as mini or snack, says Gonzlez-Cabezuelo. Bal indicates this his company is actively breeding for all types.Aust states that given the wide portfolio of customers, theyre focusing on all basic types of cucumbers and have the potential to include new innovations in existing types and mar-ginally also in exotic Asian types of cucumbers.Peter Kraan, R&D coordinator cucumbers BASF Vegetable Seeds, shares that the companys focus is on the markets where cucumbers are produced indoors, and also on pickling cucum-bers. The focus is defined by the market size and expectedBeit Alpha cucumber. Source: Meridiem Seedsprofitability of the different markets. Consumers will become more demanding with regards to production conditions but alsoTypically, these are temperature fluctuations in the late May towards health and taste. In our breeding we anticipate theseperiod that fall below 10 C. This results in undesirable changes market developments, he says.in flowering type. In our gene sources we have materials that show high stability and are the basis for breeding new varieties.SEX EXPRESSION Bal says 95 per cent of their breeding material is dedicated There is a lot of variation in the cucumbers sex expression andto female, parthenocarpic material and shares that for seed pro-there are plants with only female flowers (gynoecious) andduction an active silver component (Ag) is used to change plants that have both female and male flowers (monoecious).sex-expression from female to male.Suelmann indicates that all of their varieties for protectedDefinitively, when dealing with greenhouse high yield cultivation are gynoecious. Growing cucumbers indoormaterial we go to gynoecious (GY) parthenocarpic material. requires gynoecious and parthenocarpic varieties. Within ourMonoecious is still interesting when we work in environmentally programs we are mainly working on 100 per cent gynoeciouschallenging conditions where we need to spend initial energy types. Fortunately, cucumber is a crop where you can alteron growing a powerful plant and producing male flowers in the the sex expression easily. This makes breeding for gynoeciousbeginning is having less energy cost, says Abad. types and seed production of genetically gynoecious varietiesThere are challenges to come on the use of GY where we possible, he says. need to apply silver thiosulfate (STS) for pollinations. We need Sexual expression is one of the most important factors into continue working together as an industry to show that certain breeding, in addition to resistance and tolerance to pathogensformulations of STS can be used with no/low risk for environment.in cucumbers, says Aust.Gonzlez-Cabezuelo shares that practically all the varieties We observe that some older cucumber genotypes are moreobtained by Meridiem Seeds are parthenocarpic, whose sexual sensitive to changing the growing and climatic conditions.expression is gynoecic. He says the main obstacle with this type Especially in the European production areas of gherkins, we areof character is getting male flowers to reproduce both lines and increasingly encountering extreme weather fluctuations duringhybrids safely. The use of hormonal regulators very controlled the growing season, he adds.by our geneticist is fundamental to solving this difficulty.EUROPEAN-SEED.COMIEUROPEAN SEED I 7'