Practical findings from Horticultural Development Council trial, plus summaries of academic research and scientific trials, compiled by Dr Ken Cockshull.
Daffodil rust is a physiological disorder that results in loss of stem and leaf quality through rust-like lesions, making some cut flowers unmarketable. Industry surveys have indicated the extent of the problem and the most susceptible varieties.
Southern green shieldbug, Nezara viridula, is widely distributed across tropical and subtropical regions of the world where it is a serious pest of many important food crops.
"Identifying chemical growth regulators will provide growers with another option to control the growth of vigorous plant species and so meet required height specifications," says J&A Growers' Jamie Dewhurst.
The wood pigeon Columba palumbus is a major agricultural pest in the UK, feeding on a range of arable crops including peas, brassicas and leafy salads. HDC project FV 426 reviewed the evidence for damage levels, the efficacy and cost-effectiveness of deterrents and other management techniques and emerging controls.
The apple fruit rhynchites has increased in apple and pear orchards and if not controlled can give rise to corky scars on fruit. It can be controlled but requires treatment during or after blossom, which is undesirable. A sensitive monitoring trap is needed to direct insecticide treatments.
Mushroom yield, flushing pattern and quality are determined by nutrition.
Impatiens downy mildew, which is caused by Plasmopara obducens, is a foliar disease that is specific to impatiens.
Root diseases pose a serious threat to tomato production, with an increased risk where irrigation run-off is recycled. HDC project PC 281 used the molecular diagnostic method T-RLFP to begin to understand the diversity of microorganisms on tomato roots.
Codling moth is still the most important apple pest found in the UK and its control poses a major challenge for all growers.
HDC Project FV 364 investigated how cabbage root fly larvae (Delia radicum) locate brassica plants and tested potential treatments not involving conventional insecticides.
The production of quality container-grown hardy nursery plants requires accurate management of plant nutrition throughout the whole life of the crop.
Low light levels induce the growth of longer, weaker stems and petioles in plants, a condition known as etiolation. Such plants show reduced shelf life and may fail to meet buyer specifications and customer expectations. Etiolation can be an issue in pot herb production, so the HDC commissioned project PE 015 to investigate practical solutions.
Reports that earwigs are declining in some apple and pear orchards have raised concern for pest control and is it thought that this problem could be linked to the use of certain crop-protection products.
Infection of compost by Trichoderma aggressivum can result in up to 100 per cent crop loss in mushrooms.
Each season, strawberry growers expect to contend with certain flower and leaf pests, but they can never be quite sure when the pests will strike.
Gardeners + Garden Labourers
UK Mission Enterprise England, Surrey, Chertsey
Sahara Forest Project London (Central), London (Greater), Cambridge
Plantarea Manager - J122
Group Plant Buyer
Squires Garden Centre Farnham, Surrey
Lotus Landscapes Ltd. Laleham, Staines