Grey Wall in Tomatoes
Source: www.semena.org/agro/diseases/gray-wall-e.htm
Grey wall or blotchy ripening is a name that is indicative of the disorder where fruit do not ripen properly or ripen unevenly. Symptoms develop whilst the fruit is still green. This condition is only found on the fruit and not on the plant.
Symptoms
Affected green fruit, have large, greyish or yellowish hard blotches on the fruit. Only when the fruit is over-ripe do these areas ripen – if they ripen at all. Ripe fruit have brown or green areas on the inside of the fruit walls. The outer walls of the fruit tend to be the most affected, which is obvious once the fruit are cut.
Symptoms often develop in the midst of plants which are dense and have lots of foliage and also on plants which are growing in compacted soils. Stressed and unhealthy plants also add to the problem.
A higher incidence of this condition is found in cool, wet, cloudy conditions. Because of these conditions, the fruit do not ripen properly and “veins” develop on the inside walls of the fruit. It is these areas that always remain dark green and seldom ripen. Some people also believe that the incidence is affected by the nitrogen : potassium ratio of the fertilizer program, however this is not yet substantiated.
Control
Good growing conditions will help to prevent the problem. Ensure that plants receive adequate fertilizer and regular/even watering; and check that the soil is not compacted around the roots. Tomatoes should be grown where they receive full sun and are not heavily shaded.
Annette Welsford has a partial degree in Horticulture and a Post Graduate Certificate in marketing. Having lived in the cold, temperate and hot parts of Australia and the UK, she has gained experience over the years with gardening in a variety of climates. Annette also worked for a fertilizer company where she was responsible for developing, editing and publishing a range of technical manuals on nutrition and fungal diseases for a wide range of horticultural crops including tomatoes. Annette is Managing Director of Commonsense Marketing Pty Ltd, a publishing and marketing company, responsible for the editing, design and worldwide marketing of the How to Grow books, and other products. Commonsense Marketing also provides expert offline and online marketing consulting and design services to a variety of small to medium sized businesses.
Tags: tomato diseases, tomato gray wall, tomato grey wall, uneven ripening of tomato
