Cabbage Integrated Pest Management : An Ecological Guide.

Major Agronomic PracticesOpen pollinated variety: seed produced from natural pollination so that the resulting plants are oftenvaried: they may have characteristics from the mother plant, from the father plant or from a combinationof the two. Seed from OP varieties can often be multiplied by farmers but requires a bit of selection: onlyseed of the best fruits and plants should be used. Depending on the breeding process and the crop,commercial OPs can be very homogenous.3.2.2 Resistant varietiesAnother important aspect to consider when selecting a variety, is if the variety is tolerant or resistantagainst certain insect pests or diseases. Growing a resistant variety is one of the best and mostenvironmental safe methods of crop protection! Unfortunately, resistant varieties are not always available.Also, resistant varieties are usually not resistant to all pests and diseases that may occur.Resistant variety: an insect pest or disease cannotlive on the plant. This can be due to long or stickyhairs on a plant that hinder an insect to walk andfeed on a plant, or the excretion of toxic chemicalsby the plant, or the chemical constitution of the plantsap that make it less attractive to insects or diseases.Tolerant variety: an insect pest or disease can infect the plant butsymptoms will not be severe and the effect on yield will be none orminimal. However, infected plants may become a source of infectionfor other fields.Susceptible variety: insects or diseases can attack the plant and thismay result in yield and quality loss.Test cabbages in a varietal trialMany seed companies are willing to support demonstration plots of different varieties. For the seedcompany, the demonstration plot may be a promotion and they will often provide the seed for free.For farmer groups it may be worth the effort contacting a few companies and testing a number ofvarieties under local conditions. Some varieties may be interesting with regard to suitability to aspecific climate/season, resistance/tolerance to insect pests and diseases, yield or other factors.Make sure to include the locally used varieties for comparison.Cabbage Ecological Guide - 200012