Powdery mildew
Powdery mildew background Powdery mildew (Leveillula taurica) is most prevalent in warm, dry atmosphere. The optimum germinating temperature is approximately 25°C with humidity ranging between...
Category Archives: Crop protection
Crop protection is crucial to long term profitability of a commercial hydroponic farm. You need to know which chemicals to apply at the right time to ensure a high percentage of grade a product.
Early blight (Alternaria solani) common fungus on tomatoes
Early blight (Alternaria solani) is one of the most common funguses found on tomatoes. The fungus infects mainly the leaves, but stem and fruit infection...
Late blight – Phytophthora infestans
Late blight background Late blight (Phytophthora infestans) is very destructive under conditions of excessive moisture and low temperatures. Starts as small water soaked lesions which...
Botrytis rot or grey mould fungus – symptoms and control
Botrytis rot (Botrytis cinerea) Botrytis rot (Botrytis cinerea), also known as grey mould, is caused by the fungus Botrytis cinerea, and has become on the...
Bacterial speck
Bacterial speck, also known as Xanthomonas campestris pv. vesicatoria, Pseudomonas syringae pv. Tomato. Bacterial speck and spot are very difficult to distinguish from each other. However...
Cucumber pest and disease control
Never use chemical that are not registered by your local Department of Agriculture. A range of chemicals that can be used on cucumbers are provided...
Growth cracks in greenhouse vegetable fruit
Growth cracks symptoms There are two types of cracking found on tomato fruit. Concentric cracking are cracks that vary in depth and size found in...
Cat-face tomato fruit – genetic physiological disorder
Cat-face tomato fruit Symptoms Fruits have a long scar at the blossom end that extends inwards and renders the fruit unmarketable and disfigured (abnormal). There are...
Hollow fruit disorder in hydroponic greenhouse systems
Hollow fruit description Hollow fruit, also called puffy fruit or boxy fruit are angular in shape instead of round, however one should be careful since some...
Zippering – Physiological disorder of tomato and pepper fruit
Zippering symptoms Zippering are thin scars running from the top of the shoulder of the fruit down the length to the blossom end. These longitudinal...
Blossom drop – A sure sign of stress in hydroponic greenhouses
Blossom drop Symptoms Blossom drop (flower buds abscise) occurs prior to anthesis under stress conditions. The early indications of blossom drop are the yellowing of the...
Blossom-end-rot – most common physiological disorder in vegetable fruit
Blossom-end-rot (BER) Symptoms This physiological disorder looks like a typical fruit disease. The symptoms generally occur at the blossom-end of the fruit and begins with...
Sunscald or sun burn on vegetable fruit – sun damage that can be prevented
Sunscald or sunburn causes Sunscald may appear on foliage and fruits. The disorder is caused when the temperature of the fruit exceeds 40°C. An imbalance...
Thin spindly sick pale plants – it’s causes and solutions
At some stage a grower will see thin spindly pale plants growing somewhere in the greenhouse. Although not a physiological disorder of fruit, it is...
Small fruit in crops grown in greenhouses is a sign of stress
Getting small fruit (peppers or tomatoes) is better than getting no fruit at all. However it can be frustrating when growing to achieve 140 g...
