Soaking the contaminated blade in either full strength or 1:5 dilution of household bleach, Lysol™ Disinfectant or Pine-Sol™ will destroy the fire blight organism. Make cuts well below any visible signs of infection (40 cm) and dip tools in a disinfectant between each cut. They are most visible on bright, sunny days.Ĭurrent season infections should be cut out and burned, with oozing cankers always being removed first. A separate operation to prune out cankers is recommended. Make cuts 15-30 cm below the canker margin. Removal of cankers is a critical step in preventing and controlling fire blight. Cultural Controlįire blight overwinters in old dormant cankers in the trees. Double Nickel can be safely combined with Cueva (copper octanoate) for improved effectiveness. For best results, apply during early bloom at the beginning of a warming trend, and follow with Streptomycin or Kasumin 2 - 3 days later if warm temperatures continue to favour blossom infection.īiological fungicides are often sensitive to fungicides. These biopesticides should be used as part of an integrated fire blight management program, which includes using a risk assessment model, as well as cultural controls and antibiotic sprays when necessary. Most of these products consist of live, beneficial bacteria or yeasts which colonize blossoms and help to prevent fire blight bacteria from getting established. These products are blossom protectants, used during bloom to reduce the incidence of blossom blight. There are several biopesticides registered for suppression of fire blight on apple and pear (see table below). Once trees are large, it will be difficult for many home gardeners to get good spray coverage with a bactericide, so the other management approaches – including planting resistant varieties and avoiding overfertilizing – are especially important in home orchards.General Description Management Biological Control Make sure any bactericide or other pesticide you plan to use is labeled for the purpose for which you intend to use it, and read and follow label instructions. It is not useful to spray for fire blight at this time. I want to emphasize that once blighted shoot tips are seen, as they are now, the time for making a bactericide application has passed. Make sure not to use any product containing an insecticide during bloom, to avoid killing bees. Be aware that copper can cause russeting on apples of some varieties. Repeated applications are likely to be needed. This is another option, if a streptomycin product isn’t available. Some copper fungicides are also labeled for use during bloom on pears and apples. Ferti-lome Fire Blight Spray is a streptomycin product for home orchards. If suitable spray equipment is available, applications of a product containing the antibiotic streptomycin sulfate can be made to pear and apple trees during bloom, to protect flowers from infection. Continue to monitor the tree during the growing season to see if more blighted shoots appear.ĭuring the dormant season, before new growth begins, cut out any remaining blighted shoots and cankers. Avoid overfertilizing.īlighted shoots can be pruned out during the growing season, with cuts made 8 to 12 inches below where symptoms are seen. However, resistant does not mean immune, and in years when conditions are favorable, disease may still occur.īecause the bacteria can infect through young shoots, trees that produce a lot of new growth – such as those that have been pruned severely during the winter or received a great deal of fertilizer – are more likely to have more shoot infections. Some mayhaw varieties are more fire blight resistant than others, as well. Pear and apple varieties recommended for Louisiana have some resistance. One of the first lines of defense against fire blight is planting varieties that are resistant to the disease. Dead shoot terminals often have a “shepherd’s crook” appearance.īecause bacteria can move from place to place on a tree in water, fire blight is more likely to be a problem during rainy years like this one. Bacteria can also infect leaves at the tips of young shoots. They can then move into wood below those flowers. The bacteria spread from around cankers (dead areas on branches or trunks) to open flowers during bloom, via insects or in water. Fire blight is a common problem of pears and apples and is sometimes seen on mayhaws, loquats, and other plants in the rose family, too.įire blight is a bacterial disease. Some people have observed the tips of branches on their pear trees dying.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |