E-Book
13,99 €

Vegetables Pests Organic Control E-Book

Rudolphe Lemmens

0,0

13,99 €

Sammeln Sie Punkte in unserem Gutscheinprogramm und kaufen Sie E-Books und Hörbücher mit bis zu 100% Rabatt.
Mehr erfahren.

Herausgeber: Books on Demand
Kategorie: Wissenschaft und neue Technologien
Sprache: Englisch

Beschreibung

Vegetables Pests Organic Control is the complete guide on how to assist gardeners in growing organic vegetables. In the first section the common vegetables grown in your garden are described with the candidate pests to disturb them. A simple list of symptoms, on the plant parts, assist you in identifying the pests who can be insects, fungi, bacteria, nematodes or viruses. In the second section you shall find more detailed information on the pests and how to control them organically. Finally in the third section organic remedies are provided with detailed precision on how to use and eventually how to brew them at home.

Details

Das E-Book können Sie in Legimi-Apps oder einer beliebigen App lesen, die das folgende Format unterstützen:

EPUB

MOBI

Seitenzahl: 725

Veröffentlichungsjahr: 2020

Bewertungen

0,0

Rezensionen(0 Rezensionen)

Leseprobe

Table of content

Introduction

Legumes

Artichoke

Asparagus

Beetroot. Beet

Broad-bean

Broccoli

Brussels Sprout

Cabbage

Carrot

Cauliflower

Celeriac

Celery

Chard

Courgette

Cucumber

Eggplant

Fennel

Garlic

Green Bean. Common Bean

Kohlrabi

Lamb's Lettuce

Leek

Lettuce

Melon

Napa. Chinese Cabbage

Onion

Parsnip

Peas

Pepper. Bell Pepper

Potato

Pumpkin

Radish

Romanesco Broccoli

Rutabaga

Spinach

Sweet Corn

Tomato

Turnip

Pests

American Serpentine Leaf Miner

Anthracnose

Anthracnose of Cucurbits

Artichoke Moth

Artichoke Pear-shaped Weevil

Artichoke Root Aphid

Ascochyta Foot-rot

Ascochyta Rot

Asparagus Aphid

Asparagus Beetle

Asparagus Fly

Asparagus Fly, Asparagus Maggot

Asparagus Moth

Bacterial Blight of Garlic

Bacterial Blight of Pea

Bacterial Brown Spot

Bacterial Canker of Tomato

Bacterial Spot

Basal Rot

Bean Aphids

Bean Beetle

Bean Yellow Mosaic Virus

Beet Armyworm

Beet Curly Top Virus

Beet Fly

Beet Moth

Black Leg

Black Rot of Cabbage

Black Scurf

Boron Deficiency

Botrytis Rot

Brachyserus of Garlic

Bright-line Brown-eyes Moth

Cabbage Cyst Nematode

Cabbage Aphid

Cabbage Bug

Cabbage Club Root

Cabbage Fly

Cabbage Stem Flea Beetle

Cabbageworm

Carrot Fly

Carrot Root Nematode

Celery Fly

Celery Late Blight

Celery Miner Fly

Celery Root Rot

Cercosporosa Leaf Spot

Chlorosis

Cladosporium Leaf Spot

Click Beetle

Colorado Potato Beetle

Common Swift Moth

Cotton Aphid

Cotton Whitefly

Cotton Worm

Cucumber Mosaic Virus

Damping Off

Dark Sword-grass Moth

Diamond-back Moth

Downy Mildew of Alliums

Downy Mildew of Crucifers

Downy mildew of Cucurbits

Downy mildew of Spinach

Early Blight of Potato/Tomato

European Corn Borer

Eyespot of maize

Frosted Orange Moth

Fusarium Root Rot

Fusarium Wilt

Garden Dart Moth

Glasshouse Potato Foxglove Aphid

Glasshouse Whitefly

Grain Aphid

Gray Mold

Green Artichoke Aphid

Green Tortoise Beetle

Hawthorn Aphids

Itersonilia Canker

June Beetles

Late Blight

Leaf Blight of Maize

Leaf Mould

Leek Moth. Onion Moth

Lettuce Bacterial Rot

Lettuce Drop

Lettuce Mosaic Virus

Lettuce Root Aphid

Maize Smut. Corn Smut

March Crane Fly

Molybdenum Deficiency

Mosaic Virus on Pepper

Oignon Smut

Onion and Leek Rust

Onion Fly, Onion Maggot

Onion Thrips

Pea Aphid

Pea Downy Mildew

Pea Midge

Pea Moth

Pea Root Nematode

Pea Seed-borne Mosaic Virus

Pea Thrips

Pea Weevil

Penicillium Decay

Phoma

Potato Aphid

Potato Leaf Roll Virus

Potato Virus Y

Potato Scab

Potato Tuber Nematode

Potato Tuberworm

Potato Virus A

Potato Virus X

Powdery Mildew

Ramularia Leaf and Bract Spot

Ring Spot on Lettuce

Rust

Scab of Cucurbits

Seedcorn Maggot

Silver-Y Moth

Skin Blotch of Garlic

Slug and Snail

Soft rot

South American Miner Fly

Southern Green Stink Bug

Stem Nematode

Thistle Aphid

Tobacco Mosaic Virus

Tomato Chlorosis Crinivirus

Tomato Corky Root

Tomato Fruitworm

Tomato Leaf Miner

Tomato Russet Mite

Turnip Flea Beetle

Turnip Gall Weevil

Turnip Maggot

Verticillium Wilt

Violet Root Rot

White Rot

Xanthomonas Disease of Artichoke

Remedies

Amblyseius californicus Spider Mite

Aphelinus Predatory Wasp

Aphidius colemani Predatory Wasp

Aphidius matricariae Predatory wasp

Association with another crop or culture

Azadirachta Insecticide

Bacillus amyloliquefaciens bacterium

Bacillus subtilis

Bacillus thuringiensis

Bait based on bran and pyrethrum

Beauveria bassiana

Beauveria brongniartii Fungus

Bicarbonate of Potasium or Sodium

Black Soap

Bordeaux Mixture

Canola oil

Cabbage Collars

Certified Seed or Plants

Chamomile

Charcoal Dust

Chromatic Trap

Click Beetle Wireworms Traps

Comfrey

Common Rue

Compost Tea

Coniothyrium minitans Fungus

Dandelion

Diatomaceous Earth

Diglyphus isaea. Parasitic Wasp

Diluted Milk

Early Seeding

Elder

Eliminate the infected plants

Encarsia formosa Parasitic Wasp

Feltiella Predatory Midge

Fern

Freeze Seeds

Garlic

Hansfordia pulvinata

Heterorhabditis Nematode

Hirsutella thompsonii

Horsetail

Hot Water Treatment of Seeds

Insect-proof Net

Install Insect Hotels

Iron Phosphate Granules

Kaolin Clay Spray

Lacewings Predators

Ladybird Predatory Beetle

Lavender

Light Trap

Lithothamnium Algae

Crop Rotation

Macrolophus Predatory Bug

Micronised Sulphur

Milky Spore

Nesidiocoris Predatory Bug

Nettle

Orius Pirate Bug

Pachycrepoideus Parasitic Wasp

Phasmarhabditis Nematode

Pheromone Traps

Phytoseiulus Predatory Mite

Pyrethrum Insecticide

Pyrethrum Plant

Ramial Chipped Wood

Raise Soil pH

Remove Ants

Remove Aphids

Remove Fallen Leaves and Dead Material

Remove Infested Plants Parts

Remove Manually Pests

Remove White Fly

Repellent Plants

Review Irrigation

Reynoutria Extract

Rhubarb

Soil Solarization

Spinosad

Steinernema Nematodes

Streptomyces lydicus

Tansy

Tomato

Trap Cropping

Trichoderma Fungus

Trichogramma Predatory Wasp

Resistant Varieties

Verticillium Fungus

Watering At The Root

Wettable Sulphur

Whitefly Traps

Wood Ash

Wormwood

Index

Introduction

Introduction to organic gardening principles

Organic gardening is a holistic system that sustain the health of soils, environment and humans. It depends on ecological processes, biodiversity, and life-cycles rather than the use of chemical inputs. It combines tradition, innovation, science, feeling to benefit the environment and promote fair relationship and good quality of life. The whole garden is considered as an organism with closed nutrient and energy cycle system. It relies on farming practises preserving the long term sustainability of the soil and its habitants and reducing nonrenewable resources.

Organic gardeners use the fundamental components and natural processes of ecosystems, such as soil organism activities, nutrient cycling, and species distribution and competition, directly and indirectly as garden management tools to prevent pests from reaching damage levels. Soil fertility and and crop nutrients are managed through tillage and cultivation practices, crop rotations, cover, and companion crops and supplemented with manure, composts, crop waste material, and others.

The rules of organic agriculture allow the use of unregistered products such as decoctions, infusions and macerations of plants, which can be prepared on the farm or shared among farmers.

Plant protection products authorised for use in organic farming differ among countries depending on the differences in crops, pests, and cropping systems, as well as regulations and standards adopted by these countries. Check with your certification organism if you are a registered organic farmer before any doubt in using a product.

Introduction to the book

Identification of crop pests is important but sometimes very difficult in the garden, luckily to overcome this, damage by pests and symptoms of plant diseases are mostly specific to a vegetable and therefor more easily be distinguished in the garden. The regular (daily) inspection of the garden for pests, to determine their presence, their abundance and damage serves as information for decision making regarding control methods. Pests can be detected by visual observation, or also pheromone and trapping techniques.

Vegetables

Vegetables, the most common vegetables grown in a family garden are selected and described. Symptoms and damage to the plant parts as leaves, stems, flowers and roots are linked to the pests attacking the specific vegetable. E.g. Yellow leaves on tomato indicate early blight. Yellow leaves on beetroot indicate boron deficiency.

Pests

Pests, are selected for their commonness on the cultivated vegetables. They are short described and attention is paid to the damage and symptoms to identify them. Control methods are proposed in two remedies systems: Immediate action or proactive action.

Remedies

All the remedies proposed are described in detail, how to use, on what to use and eventually how to prepare them yourself.

Some definitions

Proactive management of pests starts with crop rotation, selection of crop plant varieties, timing of planting and harvesting, irrigation management, crop rotation, and use of trap crops and companion plants.

Cultural control methods also include such methods as handpicking insects, mowing, hoeing, flaming, soil solarisation, tilling, washing, row covers, protective nets, sticky paper collars, water pressure sprays, insect vacuums and many others.

Biological methods are the use of beneficial organisms that can be introduced or attracted to the garden to reduce insect pest populations. It exist of introducing pest's natural enemies to the garden or glasshouse where they do not occur naturally, or even smarter boosting the naturally occurring natural enemies population by providing a favourable environment to them.

Biopesticides are characterised by having minimal or no risk to the environment, natural enemies, and non target organisms due to their mode of action, rapid degradation, and the small amounts applied to control pests. They are slow acting, have a relatively critical application times, and suppress rather than eliminate a pest population

How to use the book

Checking vegetables allow you to discover symptoms or damages on leaves, stems, fruits or roots on a specific crop. In the book you consult the pages of the specific vegetables and then you look for the symptoms on leaves or other parts of the plant. E.g. You grow lettuce and find out the leaves have irregular holes. The book propose one or more pests who are provoking this damage.

Then you consult the pest section of the book, to confirm your firsts diagnoses. In this section the pest are described in more detail and if the characteristics of the pest are not covering what you have seen in the garden you shall have to search for other candidates. It is also possible that the same symptoms on the plant are provoked by more than one pest. Once the pest identified a list of remedies are proposed.

Following the gravity of pest infection or damage caused, in between the remedies you can select immediate action or proactive actions. Some remedies can be bought in garden centres others can be home made. Follow carefully the recipes provided. Allows handle products with care even home made sprays.

Legumes

Artichoke

Botanical name:Cyanara cardunculus var. scolymus

Family: Asteraceae

English name:Globe artichoke, French artichoke, Green artichoke.

Names in other languages: Artichaut (FR), Artischocke (DE), Artisjok (NL), Articiococo (IT), Alcachofra (PO), Alcachofa (SP).

Related plants: Cardoon (Cyanara cardunculus var. Altilis) selected for edible leaf stems.

Description: The globe artichoke also known by the names French artichoke and green artichoke in the U.S., is a variety of a species of thistle cultivated as a food. The edible portion of the plant consists of the flower buds before the flowers come into bloom. The budding artichoke flower-head is a cluster of many budding small flowers (an inflorescence), together with many bracts, on an edible base. Once the buds bloom, the structure changes to a coarse, barely edible form. Another variety of the same species is the cardoon, a perennial plant native to the Mediterranean region. Both wild forms and cultivated varieties (cultivars) exist.

Pests:

Symptoms on Leaves:

Brown lesions

see Ascochyta Rot or Black Rot or Leaf spot. Ascochyta rot or black rot is caused by a fungus

(Ascochyta hortorum).

It develops first on the tips of the outermost bracts of the flowerbuds. In wet conditions the bud may be affected by a dark rot. Brown lesions also occurs on stems and leaves.

Galleries

see Artichoke Pear-shaped weevi. The artichoke pear-shaped weevil

(Apion carduorum)

is a small shiny blackish bleu coleoptera. The larva are white and curved, they dig longitudinal galleries in the petioles and the large veins of the leaves of artichoke. The leaves develop pale spots, then yellow and decompose, the flowerhead develop badly.l

Leaf surface eaten

see Green Leaf Beetle or Green Tortoise Beetle. The green leaf beetles

(Cassida deflorata)

are found on artichoke and cardoon. The adults and larvae eat the leaf surface leaving a pale or brown translucent membrane.

Leaves brown and dry up

see Ramularia and Bract Spot. Ramularia leaf and bract spot

(Ramularia cynarae)

leaf symptoms consist of small in pale green to yellow-green circular spots that develops on the older foliage. Most of the leaf can turn brown and dry up.

Leaves curled and shrivelled

see Thistle Aphid, Bean Aphids. Balck Dolphin Aphids. The thistle aphid

(Brachycaudus cardui)

is brownish-yellow, pale green or brwon with a large black spot situated dorsally on the abdomen. Leaves of artichoke undergo severe curling and dense colonies occur at the base of the flower heads and on the leaves. The black aphids

(Aphis fabae)

can seriously damage the broad kidney or runner bean crop, if unattended, in a few days. It cover the plants with numerous black aphids, produce a film of honeydew who is on its turn infested by black fungus fumagine.

Leaves discolouring bronzed or silvery

see Red Spider Mite or Two-spotted Mite. The red spider mite

(Tetranychus urticae)

include red spider mite and two-spotted spider mite, species of plant-feeding mite generally considered to be a pest. Plants infested show pale mottling on the upper surface of the leaves, the underside have many tiny yellowish green mites and white cast skins and egg shells. The leaves may dry up and fall off. On the plants you may see fine silk webbing.

Leaves skeletonised

see Cotton Worm or African Cotton Leafworm. The cotton worm

(Spodoptera littoralis)

damage arises from extensive feeding by larvae, leading to complete stripping of the plants.

Leaves turn yellow

see Cucumber Mosaic Virus or CMV. Cucumber mosaic virus (CMV) causes white or yellow mottled areas on leaves. Leaf margins roll downward. Plants are stunted, with shortened stems between leaves.

Leaves turn yellow and wilt

see Artichoke Pear-shaped Weevil. The artichoke pear-shaped weevil

(Apion carduorum)

Leaves turn yellow than brown

see Verticillium Wilt. Verticillium wilt is caused by fungus (Verticillium species). Plants may be infected for a while before symptoms become visible. Initial symptoms include wilting either the entire plant may wilt or only parts of the plant may wilt. The leaves soon begin to yellow then turn brown and die.

Pale green to yellow spots

see Ramularia Leaf and Bract Spot. Ramularia leaf and bract spot

(Ramularia cynarae)

leaf symptoms consist of small in pale green to yellow-green circular spots that develops on the older foliage. Most of the leaf can turn brown and dry up.

Presence of aphids

see Green Artichoke Aphid, Bean Aphids, Black Dolphin Aphids, Thistle Aphids. The green artichoke aphid

(Capitophorus horni)

occurs only on the underside of leaves and junctions of veins but neither causes distortion nor settles on the main stems or heads. The presence of more than 200 aphids causes the plant to become weakened, leading to a reduction in size and a loss of value of the harvested head.

Presence of bugs

see Green Leaf Beetle, Green Tortoise Beetle. The green leaf beetles

(Cassida deflorata)

are found on artichoke and cardoon. The adults and larvae eat the leaf surface leaving a pale or brown translucent membrane.

Presence of caterpillars

see Cotton Worm, African Cotton Worm. The cotton worm

(Spodoptera littoralis)

damage arises from extensive feeding by larvae, leading to complete stripping of the plants.

Raised blister like areas

see Powdery Mildew. Powdery mildew is caused by a variety of closely related fungal species

(Peronospora, Bremia, Pseudoperonospora, Phytophthora).

Low soil moisture combined with high humidity levels at the plant surface favors this disease. Powdery mildew starts on young leaves as raised blister-like areas that cause leaves to curl, exposing the lower leaf surface. Infected leaves become covered with a white to gray powdery growth, usually on the upper surface. Leaves of severely infected plants turn brown and drop.

Water-soaked lesions

see Xanthomonas Disease of Artichoke. The Xanthomonas disease is provoked by a bacterium

(Xanthomonas cynarae)

it invades the bract within a few days entering through a wound. The symptoms occur in spring, on the flower head, which shows little water-soaked lesions exudating a yellowish mucus. The lesions on the flower bracts become dark brown.

Wilting of leaves

see White Rot. White Mold. Sclerotinia Wilt. White rot is a fungus

(Sclerotinia sclerotiorum)

it provoke wilting of the leaves. Rot on the collar who can extend into the roots. A thick white mycelium covers the surface of the affected parts and large black sclerotia can be seen in the decaying tissues.

Symptoms on flower buds:

Brown lesions

see Ascochyta Rot or Black Rot or Leaf spot. Ascochyta rot or black rot is caused by a fungus

(Ascochyta hortorum).

It develops first on the tips of the outermost bracts of the flowerbuds. In wet conditions the bud may be affected by a dark rot. Brown lesions also occurs on stems and leaves.

Coating of grey fungus spores

see Gray Mold. Grey Mould. Botrytis Blight. Gray mold

(Botrytis cinerea)

is a fungal disease found on a wide range of plants. Symptoms appear as grayish colored soft, mushy spots on leaves, stems, flowers and on produce. Spots may become covered with a coating of gray fungus spores, especially if humidity is high.

Galleries

see Artichoke Moth. Artichoke Plume Moth. Frosted Orange Moth. The artichoke moth

(Gortyna xanthenes/Platyptilia carduidactyla)

is a nocturnal moth, with 50 to 60 mm wingspan and greyish yellow for wings. The young caterpillar climbs along the plant and nibles the upper epidermis of the leaves, it then penetrates the veins, perforating them to expels frass, it eats through the centre of the stem to reach the head, where it forms large galleries.

Grayish colored, mushy spots

see Gray Mold. Grey Mould. Botrytis Blight. Gray mold

(Botrytis cinerea)

Water-soaked lesions

see Xanthomonas Disease of Artichoke. The Xanthomonas disease is provoked by a bacterium

(Xanthomonas cynarae)

Symptoms on stems:

Stems decay

see Collar Rot. The symptoms are the same as those caused by

Sclerotinia sclerotiorum.

A clear mould, like a fine spider's web, appears on infected areas. It is initially grayish-white, and later reddish-brown and spotted with globular pseudo-sclerotia, 0.5mm in diameter. May be confused with collar rot due to

Sclerotinia sclerotiorum

and

Sclerotium rolfsii,

which often coexist.

Galleries

see Artichoke Moth. Artichoke Plume Moth. The artichoke moth

(Gortyna xanthenes/Platyptilia carduidactyla)

is a nocturnal moth, with 50 to 60 mm wingspan and greyish yellow for wings. The young caterpillar climbs along the plant and nibles the upper epidermis of the leaves, it then penetrates the veins, perforating them to expell frass, it eats trhough the centre of the stem to reach the head, where it forms large galeries.

Sawdust a base of stems

see Frosted Orange Moth. Artichoke Moth. The larvae of the frosted orange moth

(Gortyna flavago)

and the artichoke moth

(Gortyna xanthenes)

are a pest on artichokes. Early instars feed on the upper epidermis of the leaves. Later, they penetrate the veins and finally eat through the center of the stem and reach the head where they form large galleries.

Symptoms on roots:

Presence of aphids

see Lettuce Root Aphid. The lettuce root aphid

(Pemphigus bursarius)

primary host is poplar. The body of the adults is greyish-green covered with wax. The roots of lettuce become covered with a waxy secretion, it has difficulty forming heads, the leaves become yellow and the plant may wilt and die.

Roots covered with sooty mould

see Lettuce Root Aphid.

Symptoms on whole plants:

Wilted or stunted plants

see Lettuce Root Aphid. Verticillium Wilt. The artichoke root aphid

(Protrama radicis)

is probably rather common, but is seldom seen because it lives underground feeding on the roots of plants. Sucking so much sap this causing leaves to turn yellow and plants stunted. Finding them is facilitated by the frequent presence of ants around the stem collar of an affected plant. Verticillium wilt is caused by fungus (Verticillium species). Plants may be infected for a while before symtoms become visible. Initial symptoms include wilting either the entire plant may wilt or only parts of the plant may wilt. The leaves soon begin to yellow then turn brown and die.

Asparagus

Botanical name:Asparagus officinalis

Family: Liliaceae/Asparagaceae

English name: Asparagus, Garden asparagus, White asparagus, Green asparagus

Names in other languages: Asperge (FR), Tuin Asperge (NL), Gemüse-Spargel (DE), Asparago comune (IT), Espargos (PO), Espárrago verano (SP).

Description: Asparagus (Asparagus officinalis) is an herbaceous perennial plant in the family Asparagaceae which is grown for its young shoots, or spears, which are eaten as a vegetable. The asparagus plant is tall with scale like leaves emerging from the underground stem (rhizome) and has stout stems and feathery foliage. The flowers are bell shaped and occur alone or in pairs. They are green-white to yellow in color. After flowering, a round red berry is formed with 1 to 6 black seeds. Asparagus can live for 20 or more years and can attain a height between 100–150 cm (39.4–59.1 in).

Pests:

Symptoms on Leaves:

Leaf spots with brown-reddish margins

see Cercospora leaf spot (Cercospora and Mycosphaerella) symptoms begin as small, circular to angular, brown to dark green spots with a reddish brown margin form on older leaves.

Leaves with irregular holes

see the beet army worm

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.

Plants defoliated

see two beetles feed on asparagus plants, Asparagus beetle

(Crioceris asparagi)

and the spotted asparagus beetle

(Crioceris duodecimpunctata).

Adults and larvae chew spears in spring. In summer they feed on the fronds, if present in high numbers they may defoliate the plants.

Presence of caterpillars

see the bright-line brown-eyes moth

(Mamestra oleracea)

caterpillar feeds at night, rarely during the day: it moves along and eats across the leaves. If disturbed, it drops at the end of a silk thread and remains still. During the day, it hides. see also the beet army worm

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.

Presence of honey dew on leaves

see the asparagus aphid

(Brachycorynella asparagi)

damage is primarily from a toxin that the aphids inject into the plant when feeding. The toxin causes shortened internodes on subsequent growth, resulting in a tufted appearance. Heavy populations also produce massive amounts of honeydew that may lead to considerable ant activity.

Red

stripes on roots, shoots and leaves and black spots on leaves

see Phoma. Phoma is a seed-borne disease caused by a fungus

(Phoma valerianellae).

Some seedlings wiil die shortly after germination, red stripes develop on roots, shoots and leaves, followed by the appearance of brown or black spots on the leaves.

Reddish-orange spots on leaves

see Common rust. Rust

(Phragmidium

spp.) is a fungal disease it causes white, slightly raised spots on the undersides of leaves and on the stems. These spots become covered with reddish-orange spore masses. Later, leaf pustules may turn yellow-green and eventually black.

Stunted leaves

see the greenhouse white fly

(Trialeurodes vaporariorum).

The white fly are miniscule insects coated with pure white waxy bloom. They are very polyphagous and are living in huge colonies on the under surface of the leaves.

White, slightly raised spots on leaves

see Common rust

(Phragmidium spp.).

Yellow-green to black pustules on leaves

see Common rust

(Phragmidium spp.).

Symptoms on stems:

Deformed turions

see The asparagus fly

(Platyparea poeciloptera).

The fly larvae make tunnels or galleries in the asparagus turions. The galleries prevent the sap from circulating, resulting in deficient nutrition and a gradual weakening of the crown.

Necrotic stems

see Fusarium wilt, who is a soil-borne pathogen. The fungi

(Fusarium oxysporum)

enter through the roots and interfere with the water conducting vessels of the plant. As the infection spreads up into the stems and leaves it restricts water flow causing the foliage to wilt and turn yellow.

Purple to light-brown stems

see Violet root rot

(Rhizoctonia violacea, Helicobasidium brebissonii. Helicobasidium purpureum).

Root rot is a soil-borne fungus that attacks a range of root crops, in addition to asparagus crowns, which will manifest a purple to light-brown 'fuzz' and die.

Symptoms on roots:

Galleries in roots

see The click beetle

(Agriotes lineatus).

The click beetle larvae are called "wireworm". They are extremely polyphagous and feeds on roots of numerous plant species.

Rotting of roots

see Fusarium root rot

(Fusarium solani

and

Fusarium oxysporum).

Root rot provoke rotting of the roots, turning black or brown. Root rot can cause foliar symptoms such as yellowing, stunting, and defoliation.

Symptoms on whole plants:

Plant slowly desiccates see the asparagus moth

(Parahypopta caestrum).

The moth larva feeds on the buds and hollows out the roots. This leads to the disappearance of plants which dry up in the course of the summer.

Plants stunted

see Fusarium root rot

(Fusarium solani

and

Fusarium oxysporum).

Root rot provoke rotting of the roots, turning black or brown. Root rot can cause foliar symptoms such as yellowing, stunting, and defoliation.

Yellow leaves on plants

see Common rust

(Phragmidium spp.).

Beetroot. Beet

Botanical name:Beta vulgaris

Family: Chenopodiaceae - Amaranthaceae

English name: Beetroot. Red beet.

Names in other languages: Betterave potagère. Betterave rouge (FR), Rode biet (NL), Rote Bete. Rote Rübe (DE), Barbabietola rossa (IT), Beterraba (PO), Remolacha (SP).

Description: Beets (Beta vulgaris) are herbacious biennial root vegetables in the family Chenopodiaceae grown for their edible root. The plant is usually erect with a long main root and a rosette of leaves growing on stems. The leaves are oval in shape, arranged alternately on the stem and grow 20–40 cm (7.9–15.7 in) in length. The roots are usually red in color. The plant produces sessile green flowers and can reach 1–2 m (3.3–6.6 ft) in height when in flower.

Pests:

Symptoms onLeaves:

Brown lesions on leaves

see the beet fly. The beet fly

(Pegomyia beta)

is pale grey with rusty legs and yellow with black body. The beet fly lays its white eggs on the under sides of the leaves. Maggots are hatched, which eat through the epidermis, and devour the soft inner tissues. Two or more generations may appear in a year.

Leaf spots with brown-reddish margins

see Cercospora leaf spot. Cercospora leaf spot

(Cercospora and Mycosphaerella)

symptoms begin as small, circular to angular, brown to dark green spots with a reddish brown margin form on older leaves.

Leaves curled or shrivelled

see aphids. The black aphids

(Aphis fabae)

Leaves discoulouring yellowish

see the june beetles. Adults of june beetles

(Phytophaga sp. Melolontha melolontha)

feed on leaves. Larvae (grubs) are most dangerous they feed on roots. If damage is important leaves are discolouring yellowish and plants die off.

Leaves turn yellow and wilt

see Fusarium. Fusarium wilt is a soil-borne pathogen the fungi

(Fusarium oxysporum)

Leaves turn yellow and wilt

see Beet curly top virus. Beet curly top virus (BCTV) is caused by a virus. The leaves are dwarfed and crinkled and curl upwards. Leaves turn yellow, wilt and die.

Leaves with galleries

see beet fly. The beet fly

(Pegomyia beta)

Leaves with irregular holes

see beet army worm. The beet army worm

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.

Leaves with perforations

see grass moth or slug and snails. The Dark sword-grass moth (Agrotis ipsilon) has brown forewings with a clearer area on the apical quarter. The caterpillars can attack a very wide range of cultivated plants: Potato, cereals, maize, beet, asparagus, lettuce, onion, chicory. tomato, etc. The caterpillar feeds at night, it nibbles the leaves, the petioles and the plant collar, during the day it hides. Slug and snail are most active at night, they feed on a variety of living plants as well as on decaying plant material. It chew large holes in foliage and may cause extensive damage to seedlings, tender, low-growing, leafy vegetables and ripening fruit, depositing trash.

Perforated leaves

see stem flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala)

are small coleptera with a metallic sheen. The young adults nibbles the leaves of cultivated brassicas. The larvae penetrates the plant, it gnaws within the pith, passes into the stem and may reach the terminal bud. This plants becomes bushy and stunted.

Presence of

aphids

see potato aphid. The potato aphid

(Macrosiphum euphorbiae)

is rather large sized for an aphid, from greyish-green to pink. It is very polyphagous and it infest potato, beet, cabbage. lettuce, pepper, aubergine and many others. It transmit phytopathogenic viruses as the potato virus and the beet yellow virus.

Presence of caterpillars

see brown eyes moth or army worm. The bright-line brown-eyes moth

(Mamestra oleracea)

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.

Presence of colonies of aphids

see black aphids. The black aphids

(Aphis fabae)

Raised blister-like areas on leaves

see powdery mildew. Powdery mildew is caused by a variety of closely related fungal species

(Peronospora, Bremia, Pseudoperonospora, Phytophthora).

Soft watery rot on lower leaves

see white rot. White rot is a fungus

(Sclerotinia sclerotiorum)

White to gray powder coverage on leaves

see powdery mildew. Powdery mildew is caused by a variety of closely related fungal species (Peronospora, Bremia, Pseudoperonospora, Phytophthora). Low soil moisture combined with high humidity levels at the plant surface favors this disease. Powdery mildew starts on young leaves as raised blister-like areas that cause leaves to curl, exposing the lower leaf surface. Infected leaves become covered with a white to gray powdery growth, usually on the upper surface. Leaves of severely infected plants turn brown and drop.

Yellow leaves on plants

see boron deficiency. Symptoms vary between crop species, but generally occur in the growing points or flower and fruiting parts of the plant. Young leaves will often show a general chlorosis. The upper leaves may show a reddish color.

Symptoms on stems:

Damaged stems

see sword-grass moth. The Dark sword-grass moth

(Agrotis ipsilon)

has brown forewings with a clearer area on the apical quarter. The caterpillars can attack a very wide range of cultivated plants: Potato, cereals, maize, beet, asparagus, lettuce, onion, chicory. tomato, etc. The caterpillar feeds at night, it nibbles the leaves, the petioles and the plant collar, during the day it hides.

Necrotic stems

see fusarium. Fusarium wilt is a soil-borne pathogen the fungi

(Fusarium oxysporum)

Stems stunted

see beet moth. The beet moth

(Scrobipalpa ocellatella)

mines can be detected in the leaves and leaf stems, causing a distortion in the growing shoot. With leaves spun tightly together, distorted and embossed also the veins are eaten and the petiole perforated. The larva can be find within.

Symptoms on roots:

Galleries in roots

see click beetle. The click beetle

(Agriotes lineatus)

larvae are called "wireworm". They are extremely polyphagous and feeds on roots of numerous plant species. Beet seedlings are destroyed. Potato tubers are attacked at maturity, revealing narrow, shallow galleries. The underground parts of carrot, tomato, onion, leek, chicory, lettuce, broad been can be seriously attacked.

Grubs present in the soil

see june beetles. Adults of june beetles

(Phytophaga sp. Melolontha melolontha)

feed on leaves. Larvae (grubs) are most dangerous they feed on roots. If damage is importent leaves are discolouring yellowish and plants die off.

Purplish coloration of roots

see root rot. The violet root rot

(Helicobasidium brebissonii. Rhizoctonia violaceae. R. crocorum)

causes a thick mycelial weft and spores cover the root and appear as a purplish coloration and usually decay.

Symptoms on whole plants:

Stunted plants

see stem flea beetle. The Cabbage stem flea beetle (Psylliodes chrysocephala) are small coleptera with a metallic sheen. The young adults nibbles the leaves of cultivated brassicas. The larvae penetrates the plant, it gnaws within the pith, passes into the stem and may reach the terminal bud. This plants becomes bushy and stunted.

Broad-bean

Botanical name:Vicia faba

Family: Fabaceae

English name: Broad-bean, Broadbean

Names in other languages: Fève (FR), Tuinboon (NL), Ackerbohne (DE), Fava (IT), Fava (PO), Haba (SP).

Description: Broad bean (Vicia faba) is a leguminous plant in the family Fabaceae primarily grown for its edible beans. Broad bean is a an annual vetch reaching between 0.5–1.8 m (1.6–6 ft) tall. There are often multiple stems originating from the base of the plant and the compound leaves are often broad, oval shaped, and come groups of 6 leaflets to a stem. The flowers are white with purple markings. Between 1 and 4 pods develop from each flower cluster.

Pests:

Symptoms on Leaves:

Leaf edges eaten

see pea weevil. The pea weevil

(Sitona lineatus)

belong to the coleoptera, is a small, grey-brown weevil. The adults provoke notches on the leaves of many bean and pea species. The larvae feed on root nodules and roots.

Leaves curled or shrivelled

see black aphids or pea thrips. The black aphids

(Aphis fabae)

(Frankliniella robusta)

feeds on young parts of peas, field beans, broad beans, and beans, by sucking the nymphs weaken the shoots and the flowers shrivel or remain sterile. The pods stay small and may dry up and drop off. Late sowings and late varieties of peas are particularly vulnerable.

Leaves turn yellow and die

see root nematode. The Pea root nematode

(Heterodera goettingiana)

infected beans and peas are stunted with yellowing leaves, and leaves tend to point up. At bloom, yellowing spreads rapidly from the bottom of the plant to the top. Sometimes the color is a very bright yellow. Invaded plants lack fibrous roots and nitrogen-fixing nodules. Tiny (less than 0.5 mm) cream-color, lemon-shaped cysts can be found embedded in root tissue, but once cysts mature and turn dark brown, they detach easily from root systems and are difficult to detect.

Presence of colonies of aphids

see black aphids. The black aphids

(Aphis fabae)

Presence of honey dew on leaves

see black aphids.

Raised blister-like areas on leaves

see powdery mildew. Powdery mildew is caused by a variety of closely related fungal species

(Peronospora, Bremia, Pseudoperonospora, Phytophthora).

Reddish-orange spots on leaves

see rust. Common rust

(Phragmidium spp.)

is a fungal disease it causes white, slightly raised spots on the undersides of leaves and on the stems. These spots become covered with reddish-orange spore masses. Later, leaf pustules may turn yellow-green and eventually black.

White to gray powder coverage

on leaves see powdery mildew

Symptoms on pods:

Fruit drop early

see thrips. The pea thrips

(Frankliniella robusta)

Symptoms on beans:

Beans with small holes

see bean beetle. The Bean beetle

(Bruchus rufimanus

and other

Bruchus spp.)

are small coleoptera who attacks broad bean but also pea and bean. They causes small holes in the seeds. The presence of beetles in the seeds renders them unsuitable for consumption and reduce the germination rate.

Symptoms on roots:

Roots abnormally increased or swellings

see root nematode. The Pea root nematode

(Heterodera goettingiana)

infected peas are stunted with yellowing leaves, and leaves tend to point up. At bloom, yellowing spreads rapidly from the bottom of the plant to the top. Sometimes the color is a very bright yellow. Invaded plants lack fibrous roots and nitrogen-fixing nodules. Tiny (less than 0.5 mm) cream-color, lemon-shaped cysts can be found embedded in root tissue, but once cysts mature and turn dark brown, they detach easily from root systems and are difficult to detect.

Roots damaged

see pea weevil. The pea weevil

(Sitona lineatus)

belong to the coleoptera, is a small, grey-brown weevil. The adults provoke notches on the leaves of many bean and pea species. The larvae feed on root nodules and roots.

Rotting of roots

see root rot. Fusarium root rot (Fusarium solani and Fusarium oxysporum) provoke rotting of the roots, turning black or brown. Root rot can cause foliar symptoms such as yellowing, stunting, and defoliation.

Symptoms on whole plants:

Plants stunted

see root rot. Fusarium root rot

(Fusarium solani

and

Fusarium oxysporum)

provoke rotting of the roots, turning black or brown. Root rot can cause foliar symptoms such as yellowing, stunting, and defoliation.

Broccoli

Botanical name:Brassica oleracea var. italics

Family: Brassicaceae

English name: Broccoli

Names in other languages: Chou brocoli (FR), Brocoli (NL), Brokkoli (DE), Cavolo broccolo (IT), Bróculos (PO), Brócoli (SP).

Related plants: Winter cauliflower

Description: Broccoli (Brassica oleracea) is an herbaceous annual or biennial grown for its edible flower heads which are used as a vegetable. The broccoli plant has a thick green stalk, or stem, which gives rise to thick, leathery, oblong leaves which are gray-blue to green in color. The plant produces large branching green flower heads covered with numerous white or yellow flowers. Broccoli can be annual or biennial depending on the variety and can grow to 1 m (3.3 ft) in height.

Pests:

Symptoms on Leaves:

Brownish black lesions on leaves

see early blight. Early blight of potato and tomato

(Alternaria spp)

have circular, dark brown spots with a pattern of concentric rings. the leaves turns yellow and may drop. Brown lesions may develop on the stems. On tomatoes brown patches may appear on green fruit, while more mature fruits will decay rapidly.

Coating of gray fungus spores on leaves

see gray mold. The Gray mold

(Botrytis cinerea)

Leaves curled or shrivelled

see aphids. The cabbage aphid

(Brevicoryne brassicae)

is globe-shaped and green in colour. They are entirely coated with a characteristic grey-white powder. The feeding of aphids causes imperfect growth and wither of cabbage and rape. The plants may be covered entirely by aphids, honeydew and moult.

Leaves with holes

see cabbage worm or diamond back moth. The cabbageworm is the larvae of a common white butterfly

(Pieris brassicae/Pieris rapae)

with two or three small black spots. The catterpillars chew large holes in leaves. They produce dark green excrement. The diamond-back moth

(Plutella xylostella)

damage is important on almost all cruciferae. The caterpillars first gnaw the outer leaves and then progressively move towards the young central leaves. They unite them with silken threads and soil them with their frass.

Leaves with irregular holes

see army worm. The beet army worm

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.

Perforated leaves

see flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala) are

small coleptera with a metallic sheen. The young adults nibbles the leaves of cultivated brassicas. The larvae penetrates the plant, it gnaws within the pith, passes into the stem and may reach the terminal bud. This plants becomes bushy and stunted.

Presence of caterpillars

see the cabbageworm or diamond-back moth or army worm.

Presence of colonies of aphids

see aphids.

Purple or brown irregular shaped areas on leaves

see downy mildew. Downy mildew of crucifers

(Hyaloperonospora parasitical Peronospora parasitica)

manifests as yellow, purple or brown irregular shaped areas on upper leaf surfaces, which correspond to white to gray, "downy" masses on under leaf surfaces.

Reddening, yellowing of the leaves

see club root. Cabbage Club Root is caused by a fungus

(Plasmodiophora brassicae).

White to gray, "downy" areas on under leaf surfaces

see downy mildew.

Symptoms on stems:

Damaged stems

see the grass moth. The Dark sword-grass moth

(Agrotis ipsilon)

Symptoms on roots:

Presence of maggots

see cabbage maggots. Cabbage maggot are the larvae of a fly

(Delia radicum)

it provoke tunnels into the roots and stems, causing plants to wilt in the sun and eventually stunting growth. Larvae are white maggots who can be observed in the collar or the surrounding soil.

Roots abnormally increased or swellings

see cabbage club root. Cabbage Club Root is caused by a fungus

(Plasmodiophora brassicae).

Symptoms on whole plants:

Stunted plants

see flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala)

Wilted plants

see cabbage maggot or cabbage club root.. Cabbage maggot are the larvae of a fly

(Delia radicum)

it provoke tunnels into the roots and stems, causing plants to wilt in the sun and eventually stunting growth. Larvae are white maggots who can be observed in the collar or the surrounding soil. Cabbage Club Root is caused by a fungus

(Plasmodiophora brassicae).

Symptoms on seedlings:

Collapse and dying of young seedlings

see damping off. Damping off is a soil-borne disease caused by several fungi

(Rhizoctonia, Fusarium, Phytophthora)

it provokes the rotting of stem and root tissues at and below the soil surface. Infected plants will germinate and come up, but within a few days they become water-soaked and mushy, fall over at the base and die.

Damaged cotyledons

see The Dark sword-grass moth (Agrotis

ipsilon)

Brussels Sprout

Botanical name:Brassica oleracea var. gemmifera

Family: Brassicaceae

English name: Brussels sprouts

Names in other languages: Chou de Bruxelles (FR), Spruit (NL) Rosenkohl (DE), Cavolo di Bruxelles (IT), Couve de Bruxelas (PO), Repollo de Bruselas (SP).

Description: Brussel sprouts (Brassica oleracea) are a cultivar of cabbage in the family Brassicaceae grown for their edible small leafy green buds, which resemble miniature cabbages. The plant has long, smooth and leathery leaves which can be green to purple in color and are arranged alternately on the stem. The sprouts form at the base of each leaf, in a long, spiral stem. The edible portion of the crop is the bud, which is a small cabbage-like head. It is a light green to green/blue in color. The plant is biennial but grown as an annual and can reach 0.6–1 m (2–3 ft) in height with a spread of 0.5–0.6 m (1.5–2 ft).

Pests:

Symptoms on Leaves:

Brownish black lesions on leaves

see early blight. Early blight of potato and tomato

(Alternaria spp)

Coating of gray fungus spores on leaves

see gray mold. Gray mold

(Botrytis cinerea)

Leaves curled or shrivelled

see aphids. The cabbage aphid

(Brevicoryne brassicae)

Leaves turn yellow than brown

see wilt. Verticillium wilt is caused by fungus (Verticillium species). Plants may be infected for a while before symtoms become visible. Initial symptoms include wilting either the entire plant may wilt or only parts of the plant may wilt. The leaves soon begin to yellow then turn brown and die.

Leaves with holes

see cabbage worm or diamond moth. The cabbageworm is the larvae of a common white butterfly

(Pieris brassicae/Pieris rapae)

with two or three small black spots. The caterpillars chew large holes in leaves. They produce dark green excrement. The diamond-back moth

(Plutella xylostella)

Perforated leaves

see flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala)

are small Coleoptera with a metallic sheen. The young adults nibbles the leaves of cultivated brassicas. The larvae penetrates the plant, it gnaws within the pith, passes into the stem and may reach the terminal bud. This plants becomes bushy and stunted.

Presence of caterpillars

see cabbageworm or diamond-back moth.

Presence of colonies of aphids

see The cabbage aphid

(Brevicoryne brassicae)

Purple or brown irregular shaped areas on leaves

see downy mildew. Downy mildew of crucifers

(Hyaloperonospora parasitica/Peronospora parasitica)

manifests as yellow, purple or brown irregular shaped areas on upper leaf surfaces, which correspond to white to gray, "downy" masses on under leaf surfaces.

Reddening, yellowing of the leaves

see club rot. Cabbage Club Root is caused by a fungus

(Plasmodiophora brassicae).

White to gray, "downy" areas on under leaf surfaces

see downy mildew. Downy mildew of crucifers

(Hyaloperonospora parasitical Peronospora parasitica)

manifests as yellow, purple or brown irregular shaped areas on upper leaf surfaces, which correspond to white to gray, "downy" masses on under leaf surfaces.

Symptoms on stems:

Damaged stems

see sword-grass moth. The Dark sword-grass moth

(Agrotis ipsilon)

Symptoms on roots:

Presence of maggots

see cabbage maggot. Cabbage maggot are the larvae of a fly

(Delia radicum)

it provoke tunnels into the roots and stems, causing plants to wilt in the sun and eventually stunting growth. Larvae are white maggots who can be observed in the collar or the surrounding soil.

Roots abnormally increased or swellings

see club root. Cabbage Club Root is caused by a fungus

(Plasmodiophora brassicae).

Swelling of roots

see gall weevil. The turnip gall weevil

(Ceuthorynchus pleurostigma)

is a small blackish-grey Coleoptera. The weevil lay eggs in the brassicas, the eggs and larvae, due to substances introduced, cause hyperthophisation (a gall) of the collar. Do not confuse with cabbage hernia, which never contain a larval cell.

Symptoms on whole plants:

Stunted plants

see flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala)

Wilted plants

see cabbage maggot or club rot or verticillium. Cabbage maggot are the larvae of a fly

(Delia radicum)

(Plasmodiophora brassicae).

The disease rarely kills plants but induces them to wilt when under slight water stress. Initial foliar wilting is followed by reddening of the leaves which become chlorotic and eventually necrotic. Plants may become stunted. The roots become abnormally increased and swell up at different regions. Verticillium wilt is caused by fungus (Verticillium species). Plants may be infected for a while before symtoms become visible. Initial symptoms include wilting either the entire plant may wilt or only parts of the plant

Symptoms on plantules:

Collapse and dying of young seedlings

see damping off. Damping off is a soil-borne disease caused by several fungi

(Rhizoctonia, Fusarium, Phytophthora)

Damaged cotyledons

see sword-grass moth. The Dark sword-grass moth

(Agrotis ipsilon)

Cabbage

Botanical name:Brassica oleracea var. sabauda

Family: Brassicaceae

English name: Savoy cabbage

Names in other languages: Chou de Milan. Chou de Savoie (FR), Savooiekool (NL), Wirsingkohl (DE), Cavolo verza (IT), Couve crespa (PO), Col de Saboya (SP).

Description: The cabbage plant (Brassica oleracea) is an herbaceous annual or biennial vegetable in the family Brassicaceae grown for its edible head. There are many different varieties of cabbage which include the white and red cabbage (Brassica oleracea var. capitata) and the savoy cabbage (Brassica oleracea var. sabauda). The head of the cabbage is round and forms on a short thick stem. The leaves are thick and alternating with wavy or lobed edges and the roots are are fibrous and shallow. The plant produces large yellow flowers. The densely leaved heads can range in size from 0.5 to 3.6 kg (1-8 Ib) depending on variety.

Pests:

Symptoms on Leaves:

Brownish black lesions on leaves

see early blight. Early blight of potato and tomato

(Alternaria spp)

Coating of gray fungus spores on leaves

see gray mold. Gray mold

(Botrytis cinerea)

Leaves curled or shrivelled

see aphids. The cabbage aphid

(Brevicoryne brassicae)

Leaves skeletonized

see sotton worm. The cotton worm

(Spodoptera littoralis)

damage arises from extensive feeding by larvae, leading to complete stripping of the plants.

Leaves turn yellow than brown

see wilt or black rot. Verticillium wilt is caused by fungus (Verticillium species). Plants may be infected for a while before symtoms become visible. Initial symptoms include wilting either the entire plant may wilt or only parts of the plant may wilt. The leaves soon begin to yellow then turn brown and die. Black rot, caused by the bacterium

Xanthomonas campestris pv. campestris

(Xcc), is a significant disease of cabbage and other crucifer crops worldwide. Symptoms of black rot generally begin with yellowing at the leaf margin, which expands into the characteristic "V"-shaped lesion. The bacterial infection becomes systemic, meaning that the bacterium can enter the veins of the plant and spread into the cabbage head, which can lead to serious losses in storage. Blackening of the vascular tissue is typical in severe infections.

Leaves with galleries

see leaf miner. The South American leaf miner

(Liriomyza huidobrensis)

is highly poiyphagous. The larva is primarily a leaf miner. Mines are usually white with dampened black and dried brown areas, and are usually associated with the midrib and lateral leaf veins. Mines are typically serpentine, of irregular shape, increasing in width as larvae mature.

Leaves with holes

see cabbage worm or diamond moth. The cabbageworm is the larvae of a common white butterfly

(Pieris brassicae/Pieris rapae)

with two or three small black spots. The caterpillars chew large holes in leaves. They produce dark green excrement. The diamond-back moth

(Plutella xylostella)

Leaves with irregular holes

see army worm or flea beetle. The beet army worm

(Spodoptera exigua)

young larvae or caterpillars feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage. The turnip flea beetle

(Phyllotreta atra)

adults are active leaf-feeders that can, in large numbers, rapidly defoliate and kill plants. Symptoms of flea beetle feeding are small, rounded, irregular holes. Heavy feeding makes leaves look as if they had been peppered with fine shot.

Leaves with V-shaped lesions

see black rot. Black rot, caused by the bacterium

Xanthomonas campestris pv. campestris

Perforated leaves

see flea beetle. The Cabbage stem flea beetle

(Psylliodes chrysocephala)

Tausende von E-Books und Hörbücher

Ihre Zahl wächst ständig und Sie haben eine Fixpreisgarantie.

Sie haben über uns geschrieben: