File Name: common pest and diseases of vegetable crops .zip
Although there are many insect pests and diseases of brassicas aka crucifers , most can be prevented from damaging the crops by adhering to a few basic guidelines. In general, a preventative management approach involves a combination of the following practices:. Other methods can also be employed, but the above four are fundamental to management of the most common problems listed below.
This page provides an overview of the bacterial diseases in vegetable crops. The related tools listed at the end of the page provided detailed information about the identification, symptoms, and management of bacterial diseases. It is important to have a plant diagnostics laboratory confirm the pathogen causing any diseases in a crop so that the disease can be appropriately managed.
Pathogenic bacteria cause many serious diseases of vegetables. They do not penetrate directly into plant tissue but need to enter through wounds or natural plant openings.
Wounds can result from damage by insects, other pathogens, and tools during operations such as pruning and picking. Bacteria only become active and cause problems when factors are conducive for them to multiply. They are able to multiply quickly. Some factors conducive to infection include: high humidity; crowding; poor air circulation; plant stress caused by over-watering, under-watering, or irregular watering; poor soil health; and deficient or excess nutrients.
Bacterial organisms can survive in the soil and crop debris, and in seeds and other plant parts. Weeds can act as reservoirs for bacterial diseases.
Bacteria spread in infected seed, propagating material and crop residues, through water splash and wind-driven rain, and on contaminated equipment and workers' hands. Overhead irrigation favours the spread of bacterial diseases. Warm, wet weather favours the development of some bacterial diseases, while others are favoured by cool, wet conditions.
Development is often arrested by hot, dry conditions, but may exacerbate symptoms once the plant is already infected e. Bacterial wilt caused by Ralstonia solanacearum. Sometimes bacterial ooze may be seen on diseased plant tissue.
However, symptoms of bacterial diseases may be confused with those caused by fungal diseases. It is important to have diseased tissue examined in a plant diagnostics laboratory to confirm the type of pathogen causing the disease. Different strains pathovars — pv. For example: Xanthomonas campestris pv. Bacterial diseases in vegetable crops. Bacterial diseases - an overview Common bacterial diseases and crops affected Management Source of information and related tools. Some examples of common bacterial diseases of vegetable crops are provided in the table below with some typical symptoms.
Light-brown to yellow V-shaped lesions on the leaf, which become brittle and dry with age. Vein blackening with the necrotic area.
Bacterial canker Clavibacter michiganensis pv. Tomato; capsicum; chilli Seedlings may die and older plants may wilt and die eventually. Older plants have leaves that turn yellow and wilt only on one side. Cankers on stems and fruit. Tissue inside stems becomes discoloured. Bacterial soft rot Pseudomonas spp. Warm, wet conditions.
Wide range of vegetables, including lettuce; brassicas; cucurbits; tomato; capsicum; potato; sweetpotato; carrots;herbs. Wet, slimy, soft rot that affects any part of vegetable crops including heads, curds, edible roots, stems and leaves. May have a disagreeable odour. Range of vegetables including lettuce; cucurbits; tomato; capsicum. Lettuce — Large brown to black circular areas that start as small translucent spots; usually on outer leaves.
Tomatoes and capsicums — Greasy spots on leaves and stems that go from tan to black; fruit may have circular spots with central scab. Bacterial wilt Ralstonia solanacearum High temperatures, high soil moisture and poor drainage. Once infection has occurred, severity of symptoms is increased with hot and dry conditions, which facilitate wilting. Potato; tomato; capsicum; eggplant. Wilting, yellowing and stunting of plants but they may wilt rapidly and die without any spotting or yellowing; vascular tissue appears brown and water-soaked; a white ooze appears when pressure is applied to affected tubers or stems.
Beet; spring onions; leeks; rocket; coriander. Beet — irregular, round leaf spots with a grey centre surrounded by a purple margin. Leeks — brown streaking on the shank. Bacterial blight Pseudomonas syringae pv.
Water-soaked spots on leaves and stipules which become dark-brown and papery in warm weather or black in cool weather. Water-soaked spots on pods that become sunken and dark-brown.
Bacterial speck Pseudomonas syringae pv. Small dark spots surrounded by a yellow halo on leaves; dark raised specks on fruit. Bacterial brown spot Pseudomonas syringae pv. Tan to reddish-brown spots on leaves. Water-soaked spots on pods which enlarge and become sunken and tan with distinctive reddish-brown margins. Peppery leaf spot — Pseudomonas syringae pv. The key means of bacterial disease management include:.
Exclusion or eradication of the pathogen quarantine and use of pathogen-tested seeds and propagated materials Use of clean transplants Monitor crops regularly and use predictive models Reduce the pathogen levels by crop rotation Remove weeds and incorporate crop residues that can host the disease Protect the host plant by using resistant plant varieties Minimise mechanical damage to crops and damage by insect pests Avoid working in crops when they are wet Spray with a registered bactericide when weather conditions favour disease development to prevent infection Understand chemical resistance and rotation of chemical groups If the plants are already infected, isolate and destroy them and prune infected leaves, but avoid excessive handling of diseased plants; if the disease is systemic and has spread throughout the plant, the plant cannot recover and should be destroyed burning or burying Use correct temperatures and packing conditions during transport and storage.
Seedlings may die and older plants may wilt and die eventually. High temperatures, high soil moisture and poor drainage.
Content Content 1. Diseases - Bacterial. Pests - Insects. See questions about Cauliflower. Cauliflower plant. Close-up of cauliflower florets.
Pathogens: biological agents that cause disease. • Symptoms: visible reaction of plant to infection by disease-causing pathogen. • Inoculum: part of a pathogen.
Flea beetle Seedcorn maggot. Western flower thrips Whitefly. General nutrient deficiencies and toxicities Herbicide injury. Together, the two websites contain 1, fact sheets which provide up-to-date, research-based information on problem insects, diseases, and weeds and their management. The websites have been upgraded and the new versions are now available online.
This page provides an overview of the bacterial diseases in vegetable crops.
Phytophthora blight is perhaps the most serious disease of cucurbits in Indiana. The plastic-covered structure blocks rain, snow and strong wind that crops are exposed to when growing in the open field. Free Download Boxwood Blight Product Code: BPW This publication provides information about boxwood blight a fungal disease that affects boxwood plants ; images of the symptoms and signs of this fungal disease and management options. This publication examines how fungicides are classified and recommends management practices particular to pome fruit that can prevent fungi from developing resistance to these products. Free Download Disease Management Strategies for Horticultural Crops: Fungicide Rotations for Nursery, Greenhouse, and Landscape Professionals Product Code: BPW This publication examines how fungicides are classified and recommends management practices to prevent fungi from developing resistance to these products.
This page provides an overview of the fungal diseases in vegetable crops. The related tools listed at the end of the page provided detailed information about identification, symptoms, and management of fungal diseases. It is important to have a plant diagnostics laboratory confirm the pathogen causing any diseases in a crop so that the disease can be appropriately managed. Fungi constitute the largest number of plant pathogens and are responsible for a range of serious plant diseases. Most vegetable diseases are caused by fungi.
In Texas, the greatest challenge to vegetable producers is in the area of pest control. The mild climate prevalent in most of the state is extremely favorable for all forms of crop pest to flourish weeds, insects and diseases. Limited tools to combat these problems is one of the major contributing factors to the high risk associated with vegetable production in general. Successful production of organically grown vegetables requires an even higher level of management for profitability to occur because even fewer control tools are available to producers using this production system. Organic producers have to rely heavily upon them minor details of vegetable culture in order to avoid problems. Pest control is often a result of the cumulative effects of many production practices. Emphasis is placed on prevention rather than control.