Transcript 1.蔬菜害虫（总论）

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《蔬菜害虫》
华南农业大学资源环境学院农业昆虫学课程组制作
果蔬害虫
-蔬菜害虫
内
容
概述
中国南方主要蔬菜种类简介
中国南方主要蔬菜害虫种类简介
蔬菜地生态系统的特点
蔬菜害虫的发生特点及对防治的要求
详细讲解几种为害严重的蔬菜害虫
蔬菜害虫的无公害防治
Part 1
中国南方主要蔬菜种类
Group 1 Chinese
Cabbage Group
• Flowering Chinese
Cabbage
• Pak-choi
• Chinese Cabbage etc.
Family: Cruciferae
Genus: Brassica
Group 2 Cole Crop
– Chinese kale
– Cauliflower
– Broccoli
– Cabbage
Family: Cruciferae
Genus: Brassica
Group 3
Green Vegetables
– Water spinach
– Lettuce
– Celery
Family:
Convolvulaceae
Compositae
Chenopdiaceae
Group 4
Gourds
–
–
–
–
–
Chieh-qua
Wax gourd
Cucumber
Sponge gourd
Pumpkin, etc.
Family:
Cucumbitaceae
Group 5
Vegetable legumes
– Asparagus bean
– Kidney bean
– Vegetable pea
– Vegetable
soybean.
Family:
Laguminosae
Group 6
Solanaceous Fruits
• Tomato
• Egg plant
• Pepper, etc.
Family:
Solanaceous
Group 7
Root Vegetable
• Radish
• Carrot
• Table beet.
Family:
Cruciferae
Umbelliferae
Chenopodiaceae
Group 8
Tuber Crops
•
•
•
•
•
Taro
Yam
Yam bean
Ginger
Potato, etc.
Family:
Araceae, Dioscoreaceae,
Zingiberceae,
Laguminosae
Group 9
Bulb Crops
•
•
•
•
Onion
Chinese chive
Garlic
Scallion, etc.
Family:
Liliaceae
Group 10
Aquatic Vegetables
•
•
•
•
Watercress
lotus root
Chinese arrowhead
Water bamboo, etc.
Family:
Cruciferae
Nymphaeaceae
Alismatacear
Gramineae
一、中国南方蔬菜
主要害虫简介
害虫种类
十字花科蔬菜害虫 茄、瓜、豆类蔬菜害虫
鳞翅目
鳞翅目
小菜蛾、 菜青虫
棉铃虫、烟青虫、玉米穗蛾
斜纹夜蛾、甜菜夜蛾、
小地老虎、豇豆荚螟、 豆野螟
粉纹夜蛾、 菜螟
粉虱类
烟粉虱（A型、B型）
同翅目
温室白粉虱、 纹翅粉虱
甘蓝蚜、萝卜蚜
螨类
桃蚜
朱砂叶螨、截形叶螨、
二斑叶螨、侧多食跗线螨
鞘翅目
黄条曲跳甲
大、小猿叶甲
其它
节瓜蓟马、瓜蚜、美洲斑潜蝇、
黄守瓜、黑守瓜
小菜蛾 Plutella xylostella (L.)
Diamondback moth
菜青虫
Pieris rapae (L.)
Cabbage Butterfly
Eggs
Adult
1. Its host include Brassica species. Cultivated and wild Cruciferae. It is widespread throughout Europe and much of
Asia, North Africa, Australia, New Zealand, Hawaii, Canada, USA and Mexico.
2. Damage:The larvae feed singly, usually deep in the cabbage heart, making holes in the leaves, even eat up all leaf
blade, only the main veins are left, with frass accumulation. The caterpillars prefer to feed in the ‘heart’ of the
cabbage and occasionally cause heavy infestations and partial defoliation. In Guangdong Province there may
be 7-8 generations per year.
3. Identification
•
Adult:Adult is a white butterfly with a wingspan about 45-55 mm in the female. The wings bear
several black markings.
•
Eggs:The bulletin-like eggs are laid singly on low surface of the leaves. There are many vertical ridges on the
surface of egg.
•
Larva: Fully-grown larva is about 30 mm long, velvety green with a faint yellow dorsal strip, and a row of
yellow spots along each side in line with the spiracles.
•
Pupa:The pupa is shuttle-like form, sharply angled, attached usually to the underside of the
leaf by a loop of silk.
Larva
Pupa
斜纹夜蛾
Spodoptera
litura (F.)
Common Leafworm
Adult
1.It is a totally polyphagous pest and feed on a very wide range of crops including vegetables, cotton, rice, tomato and tobacco. Other host
plants include Citrus, cacao, sweet potato, rubber legumes, sorghum, maize etc.
2.Distribution:It mainly distributes in South and Eastern Old World tropics, including Pakistan, India, Bangladesh, Sri Lanka, China,
Korea, Japan, Thailand, Vietnam, Philippines, Indonesia, Austral-Asia, Pacific islands, Hawaii and Fiji.
3.Damage:This caterpillar is basically a leaf-eater. Heavy infestations can seriously defoliate the crops, especially the young plants.
•
Newly hatched larvae are gregarious and remain together and skeletonize the leaf on which they feed. Later they disperse and
become more solitary and nocturnal in habits. One generation can be completed in as little as 24-30 days, and in the humid tropics
there may be 8 generations annually.
4. Identification:
•
Adult : The adults are pale brownish moth, with the yellow-brown forewing having a distinctive pale band medially: wingspan is 30-40 mm.
•
Eggs:Eggs are spherical (0.3 mm) in diameter, and laid on the undersides of leaves in batches of 100-300 and covered with yellow colored hair-scales.Each female lays
about 100-2000 eggs, hatching requires 2-6 days.
•
Larvae:The newly hatched larvae are pale green at first, and with a distinct black band on the first abdominal segment. Later they
become brown with dark marking, with yellow lateral and dorsal stripes.The lateral yellow strip is bordered dorsally with a series
of semi-lunar marks.
•
Pupa :Pupation takes place in the soil in an earthen cell, just beneath the surface, The pupa is dark red, 15 -20 mm long.
Eggs
Larvae
甜菜夜蛾
Spodoptera exigua
Beet Armyworm
Adult
1.It attacks more than 170 different species of host plants including cabbage, radish, lettuce, eggplant, pepper,
tomatoes, potatoes, beans gourds, rice, cotton, sugar beet, tobacco, etc.
2.Distribution:Africa, Southeast Asia, Central and South Europe, Middle East, Australia, Southern USA, India,
Southern China, Philippines, Indonesia, and Canada.
3.Damage:Young larvae eat foliage within webs underside of the leaves. The caterpillars are gregarious, moving in
swarms, and destroying the young leaves and stems of the host plants. Young seedlings can be completely
destroyed, but older plants often recover after an attack and may be still vigorously. Young larvae skeletonize
the underside of the leaves, but later as they grow they eat the entire lamina. In South China there are usually
eight generations.
4. Identification:
•
Adult:The adult is a small brown moth of wingspan up to 25 mm, and the fore wing is grayish-brown with two
yellow spots near the center. The hind wing is a translucent white with narrow brown borders, There are rather
nondescript in appearance and not easy to recognize.
•
Eggs:Eggs are laid on the leaves of the host plants, in clusters, several layers thick, and covered with hairs from
the female abdomen. Each cluster contains 50-300 eggs, one female can lay 300-900 eggs (up to 1700). Eggs
usually hatch after 2-4 days.
•
Larvae: The larvae are very gregarious, at first green, later becoming variable green or brown usually with a
lateral strip. Young larvae skeletonize the underside of the leaves, but as they grow they eat the entire
lamina.Pupa:Pupation takes place in the soil and lasts about 6 days.
Eggs
Larvae
粉纹夜蛾
Trichoplusia ni
Cabbage looper
Eggs
Larvae
蔬菜蚜虫
Vegetable aphids
1 萝卜蚜
Lipaphis erysimi
Turnip Aphid
2 桃蚜
Myzus pericae
Green Peach Aphid
3 甘蓝蚜
Brevicoryne brassicae
Cabbage Aphid
1. Cabbage aphid and turnip aphid mainly feed on
cruciferae. Cabbage aphid prefers cabbage and
other Brassica spp but turnip aphid likes Chinese
cabbage and radish better. Green peach aphid is
truly a polyphagous species; about 875 plants in 35
different families are recorded as its hosts. The
main host is peach, the alternative hosts include
potato, tomato, tobacco, beet, cereals and
vegetables. All three species of aphids occur
commonly and mixed on cruciferous vegetables in
China.
2.Distribution
•
Cabbage aphid: The aphid distributes throughout
the world in temperate and subtropical climates.
In China it occurs nearly all parts of the country
besides Tibet .
•
Turnip aphid: Mostly in temperate and subtropics
regions. In China it is dominate species in
Xinjiang autonomic distract.
•
Green aphid: A completely cosmopolitan species
with a worldwide distribution.
•
All species of the aphids occur year around in
South China. No eggs are found in the host plants
during the winter. All stages of the pests can be
found on the vegetable crops in winter season.
They reproduce by parthenogenesis. The
population increases very rapidly under favorite
conditions.
3.Damage:
•
Cabbage aphid: The aphid attacks many crucifers,
especially cabbage, cauliflower. It is known to
transmit a number of virus diseases in the host
plants. Nymphs and adults suck plant sap, causing
distortion, stunting. curling, wilting and often lead
to death of these host plants when severely attack
happened.
4. Identification
•
Turnip Aphid: Turnip aphid is similar to the
cabbage aphid in appearance, but has a more
distinct green to yellow-green color with less
noticeable powdery wax on the body, and it lacks
the dark transverse marks on abdomen.
•
Green Peach Aphid: Green peach aphid is rather
slender in form, light green or yellow, with
indefinitely darker stripes on the abdomen.
•
Cabbage Aphid: Cabbage aphid is grayish-green in
color and the body is covered with a fine powdery
wax, which gives heavily infested plants a whitish
appearance.
Turnip Aphid
Green Peach Aphid
Cabbage Aphid
黄曲条跳甲
Phyllotreta striolata
Stripped Flea Beetles
大猿叶甲
Colaphellus
bowringi
Cabbage Leaf Beetle
1.Host:The two species are common pests on vegetable crops,
especially on Brassicous. In South China, these pests mainly
attack radish and cabbages.
2.Damage:Both the larvae and the adults feed on the foliage of the
host plants. When heavily damage almost the whole foliage
is eaten and just the veins are left.
3.Life history:In South China, Colaphellus bowringi can complete
5-6 generations per year, while Phaedon brassicae occurs 5
generations. Usually the two species are mixed occurrence in
a same vegetable plantation. Adult female of Colaphellus
bowringi lay eggs in cluster with several to 20 individuals,
but eggs of Phaedon brassicae are laid separately on the
surface of the host plants. Both the larvae of the two species
undergo 4 instars.
4.Identification
Colaphellus bowringi (Cabbage leaf beetle)
(1)Adult
–
–
–
–
–
Adult
Shape: Elliptical
Size: 4.7 mm long
Color: Blue to black
Punctures on the elytra: Irregulars arrangement
Scutum: Triangular
(2)Larva
小猿叶甲
Phaedon
brassicae
Daikon Leaf Beetle
–
–
–
–
Size: 7.5 mm long
Color: head is black, thorax and abdomen are grayish
yellow
Spots: A pair of dark lateral-spots on each segment of
thorax and abdomen
Size: 6.0 mm long
Adult
Phaedon brassicae(Daikon leaf beetle)
(1)Adult
–
–
–
–
–
Shape: Oval
Size: 3.5 mm long
Color: Blue to green
Punctures on the elytra: Arrange in vertical lines.
Scutum: Oval
(2)Larva
–
–
–
Size: 6.0 mm long
Color: head is black, thorax and abdomen are grayish
yellow
Spots: Four pair of dark lateral-spots on each segment
beside the prothorax and the last segment of abdomen
Larvae
Damage
烟粉虱A型 Bemisia tabaci
Adult
Sweetpotato Whitefly
Eggs
Nymph
Pupa
烟粉虱B型（银叶粉虱）
Bemisia tobacci
Tobacco Whitefly
Silverleaf whitefly
Adult
Nymph
Pupa
温室白粉虱
Trialeurodes vaporariorum
(Westwood)
Greenhouse Whitefly
Adult
Nymph
Pupa
纹翅粉虱
Trialeurodes abutilonea (Haldeman)
Bandedwinged
Whitefly
朱砂叶螨
Damag
e
Tetranychus
cinnarinus
Carmine Spider Mite
1.Host:It damages a very wide range of wild and cultivated plants including eggplant and
gourds. Cotton is its main host plant
2.Distribution:Africa, Middle East, Pakistan, India, Sri Lanka, Southeast Asia, Australia, USA,
Japan, China, Central and South America.
3.Damage:It causes clusters of yellow spots on the upper side of the leaf especially between the
main veins near the leaf stalk. Later the affected areas spread, the leaf reddens and
finally withers and is shed. Red or greenish mites just visible to the unaided eye can be
seen on the underside of the leaf. About 15-18 generations occur per year in South
China.
4.Identification
Adult: The adult females are oval, red or greenish, and 0.4-0.5 mm long. The males are slightly
smaller. Fine strands of silk are spun by the adults and form an open web above the
leaf surface.
Egg: The eggs are spherical, whitish, about 0.1 mm on diameter. They are laid singly on the
underside of leaves
Larva: The larva is six-legged, pinkish, and slightly larger than the egg. They are four pairs of
legs and are greenish or reddish.
Eggs
Male Adult
Female Adult
二斑叶螨
Tetranychus urticae Koch
Twospotted spider mites
侧多食跗线螨
Polyphagotarsonemus
latus
Yellow Tea Mite
Damage egg plant
1.Hosts:Tomato, potato, beans, peppers, tea, cotton and many other plants.
2.Distribution:It is virtually cosmopolitan species, but records are sparse in
some areas. Recorded from Europe, Africa , Asia, Australia, USA, and
South America .
3.Damage:The blades of flush leaves are cupped or otherwise distorted, with
corky brown areas between the main veins on the underside of the leaf.
These corky areas are often bounded by two distinct brown lines
parallel to the main vein, the edges of the leaf being undamaged.
4.Identification
Adult: Females are elliptical-shaped, white to yellow, and about 0.2 mm in
length, four pairs of legs. Males are slightly diamond-shaped, yellow,
four pairs of legs, the fourth pair of legs are bigger than others.
Egg: Eggs are laid singly on the undersides of flush leaves. They are oval in
outline but flattened on the lower side.
Larva: The larva are minute, white, and pear-shaped.
Damage tomato
Damage green pepper
棉铃虫
1.It is a common species of pests on vegetables, and sometimes a dominant
one on cotton, tobacco, tomato, bean, maize and sorghum as well..
This species is a sporadically very serious pest in many parts of the
world. It is completely polyphagous , and very widespread.
2.Distribution:It distributes tropics, subtropics, and warmer temperate
regions of the Old World, extending as far north as Germany and
Japan.
3.Damage:Clean circular holes are bored in flower buds and balls of all
sizes. The bracteoles of buds open out causing the condition known
as ‘flared’ squares; these square then die and are shed. The
caterpillar also feeds directly on foliage of vegetable crops.
4.Life history:Egg-laying starts about 4 days after emergence and may
continue for a further 10 days. Each female may lay 1,000 or more
eggs. Eggs are laid singly, stuck on to the host plant; hatching takes
place after 2-4 days. Young caterpillars feed on small pods. Older
caterpillars feed on small squares and terminal buds, and bean
flowers and small bolls. They also burrow into large pods and eat the
developing seeds. The caterpillars often feed with their head inside
the boll or bean, but with the posterior part of the body outside. The
full-grown larva burrows into the soil and pupates there. The shiny
brown pupa is about 16 mm long; the pupal period usually lasts 1014 days. In the tropics there are usually 5-6 generations annually.
5. Identification
•
Adult: The adult is a stout-bodied, brown moth, of wingspan 40-44
mm; the hindwing is pale but with a broad dark border.
•
Egg: The eggs are spherical, about 0.5 mm in diameter, yellow when
laid but turning brown as the embryo develops. Eggs are laid singly,
stuck on to the host plant.
•
Larva: The larva is a stout caterpillar of variable color but often
greenish or brownish. The body is marked with longitudinal bands
alternatively dark and pale; the pale bands down the sides of the
body are particularly noticeable. The full-grown larva is about 40
mm long.
•
Pupa: The full-grown larva burrows into the soil and pupates there.
The shiny brown pupa is about 16 mm long.
Heliothis armigera
Cotton bollworm
Adult
Larva
Damage
烟青虫
Heliothis virescens (Fabricius)
Tbacco budworm
Damage
玉米穗蛾（美国棉铃虫）
Helicoverpa zea
Corn earworm
Larva
Damage
小地老虎
Agrotis ipsilon
Black Cutworm
1.This is a cosmopolitan pest of sporadic importance on many crops in different parts of
the world. It can cause severe damage in many crops.
2.Hosts:A polyphagous cutworm attacking the seedlings of most crops, in particular on
cotton, rice, potato, tomato, tobacco, cereals, and crucifers.
3.Distribution:Almost completely cosmopolitan, from northern Europe, Canada, Japan,
down to New Zealand, South Africa, and South America. It has not been
recorded to date from a few areas in the tropics.
4.Damage:The young larvae feed on the leaves of the host plants; the older caterpillars
feed at the base of crop plants or on the roots or stems underground. Seedlings
are typically cut through at the ground level; one caterpillar may destroy a
number of seedlings in this manner in a single night, often working along the
plant rows.
5. Life cycle:The life cycle from egg to adult takes 32 days at 30℃, 41 days at 26℃, and
67 days at 20 ℃, respectively.
6.Identification
Adult: The adults are large, dark noctuids with wingspan of 40-50 mm, with a gray
body; and gray forewings are almost white basely but with a dark terminal
fringe, paler in the males.
Egg: The eggs are white, globular, and ribbed, 0.5 mm in diameter.
Larva: The larvae are brownish above with a broad pale gray band alone the mid-line,
and with gray-green sides with lateral blackish stripes. The head capsule is
brownish-black with two white spots. The general appearance of the caterpillar is
blackish, hence the common name of ‘black cutworm’. The mature caterpillar is
25-35 mm long.
Pupa: The pupa is dark brown, 20 mm long, with a posterior spine.
Adult
Damage
Larva
Seeding is cut
through at the
ground level.
美洲斑潜蝇
Liriomyza sativae
American Leaf
Miner
1.Distribution:It is almost cosmopolitan in distribution.It is an new imported pest.
And has been found in several provinces in South China: Guangdong,
Hainan, Guangxi and Fujian. It has caused very serious damage in
vegetable production in recent years in China.
2.Host:The host plants are included over 100 species of plants, with a preference for
beans, cucumbers and tomatoes.
3:Damage:This pest is a polyphagous. It damages the host plants by adult feeding
punctures, oviposition punctures and larval mines. The larvae feed within
the leaf, making a long serpentine tunnel which is usually white with
dampened black and dried brown, and irregular shapes, increasing in
width as larval development. If many leaves are mined the yield may be
reduced; In Brassica the damage affects saleability. Heavily infested leaves
shrivel and wither.
4.Life history In South China the life history of this pest occurs throughout the year.
It completes the life cycle in 13-17 days in summer and in 50-60 days in
winter. There may be 14-16 generations takes place per year.
5.Identification
Egg: Egg is 0.2-0.3 mm in length, with slightly translucent
Larva: Larva is headless maggot, about 3 mm in length when full grown. 1stinstar
larva colorless, but pale yellow-orange on hatching. Later instars yelloworange. Larvae with a pair of posterior spiracles shaped like a triple cone.
Each posterior spiracle opens by three pores, one pore located toward the
apex of each cone.
Pupa: Pupa oval, slightly flattened ventrally, pale yellow-orange but often
darkening to golden brown.
幼虫潜入叶肉中，
留下弯曲的蛀道
节瓜蓟马
Thrips palmi
Palm Thrips
Adult
1.Distribution:Southeast Asia , Japan, South China.
2.Host:This insect is one of the most important pests on gourd and potato family in South China.
3.Damage:The larva and adult suck the juice of the plants on the young leaf, bud, and young fruit, leading to wither or
dwarf of the young leaf. The hairs on the surface of the host plant darkened, the fruits dropped and the yield lost
obvious when severe damage happens in the plantations.
4.Identification
•
Adult: Adult is about 1 mm in length, golden, head slightly square. Eyes project, ocelli 3, reddish, ranging in
triangle, antenna 7 segmented, wings narrow.
•
Egg: Egg is 0.2 mm in length, elongated, white-yellowish.
•
Nymph: Nymph yellow-whitish, eyes red in 3rd instar.
5.Life History:This insect can occur over 20 generations, with heavily overlapping between generations. It develops and
reproduces all over the whole year in the plantations in South China. Usually damage gourds, beans and eggplant
during the period of March to October, and forming 3 peaks of population dynamics in late May to mid-June, midJuly to early-August , and September, respectively. In autumn the population is so high that server damage is led.
Nymph
Damage
瓜蚜（棉蚜）
Aphis gossypii Glover
Melon aphids
豇豆荚螟
Maruca testulalis
Pea Pod Borer
Adult
1.Host plants:The insect can attacks Pigeon pea, lima bean, green peas, cowpeas, and other Leguminosae.
2.Distribution:Almost completely pantropical regions in distribution, extending up into the subtropics and warmer
temperate areas, but only a few record from Australia.
3.Damage:Early instar larvae feed inside the developing seeds, but later instars feed freely inside the pods. The
immature caterpillar may leave the original pod and penetrate one or more fresh pods before reaching
maturity.This is very common pest of pigeon pea and other legume crops in many parts of the world;
sometimes recorded as a serious pest.
4.Identification
•
Adult: The adult moth is brown, with a wingspan of 24-27 mm. There are two white and transparent spots in
the middle of the forewing.
•
Egg: The eggs are oval, shiny white, 0.6 mm in length. They are laid singly or in small groups (up to 6) on
immature pods.
•
Larva: The caterpillar is blue with a yellow head, and 12-17 mm long when mature. Caterpillar wriggles very
violently if the pod is opened and it is disturbed.
•
Pupa: When the larva is full-grown it leaves the pod, drops into the ground. And about 3 cm below soil level it
spins a cocoon and here it turns into a yellowish-brown pupa with 6-10 mm long.
Larva
Damage
其它食叶甲虫
•二十八星瓢虫
Henosepilachna
vigintioctopunctata
•黑守瓜Aulacophora lewisii
• 黄守瓜Aulacophora
femoralis
蔬菜害虫天敌种类
Natural Enemies of
Vegetable Insect
Pests
瓢虫
lady beetles
七星瓢虫
Coccinella
septempunctata
Adult
Seven spots lady
beetle
Larva
澳洲瓢虫
Rodolia cardinalis
Vedalia Beetle
异色瓢虫
Leis axyridis
Multicolored Asian
Lady Beetle
虎甲科(Cicindelidae)
六斑虎甲
Cicindela sexpunctata Fabricius
Six-Spotted Green Tiger Beetle
步甲科
Carabidae
Lebia grandis
隐翅虫科
Staphylinidae
Aleochara bilineata
盲蝽科 (Miridae)
Deraeocoris nebulosus
花蝽科 (Anthocoridae)
Orius tristicolor and O. insidiosus
Nnnn
hhh
Ll
长蝽科
(Lygaeidae)
普通草蛉
Chrysopa carnea
食蚜蝇
Hover Fly
Adult
Larva
螳螂
Mantis
蜘蛛 Spiders
智利小植绥蟎
Phytoseiulus persimilis
寄生蜂
Parasitoids
• Egg-parasitoids
• Larva-parasitoids
• Pupa-parasitoids
Trichogramma
Apanteles glomeratus
Pteromulus puparum
姬蜂科 Ichneumonidae
岛弯尾姬蜂
Diadema insulare
K
K
茧蜂科
(Braconidae)
菜粉蝶绒茧蜂
Apanteles glomeratus
跳小蜂科(Encyrtidae)
Metaphycus alberti
蚜小蜂科
Aphidiinae
丽蚜小蜂
Encarsia formosa
缨小蜂科(Mymaridae)
Anaphes flavipes
赤眼蜂科
(Trichogrammatidae)
玉米螟赤眼蜂
Trichogramma ostriniae
寄蝇科
(Tachinidae)
因感染真菌而死的甜菜
夜蛾幼虫。The larvae of
beet armyworm are dead
of a kind of fungus.
因感染真菌而死的小菜
蛾幼虫。
entomopathogenic
fungus,
因感染真菌而死的烟粉虱.
Paecilomyces fumosoroseus
二、蔬菜地生态系统的特点
1、生长周期短、生态不稳定。
• 一般十字花科蔬菜生长周期：30-50天。瓜豆类较
长，但也不超过1个季节。不利于天敌的繁殖和存
活。
• 管理精细，经济价值高。
2、品种多样，季节性变化大。
• 蔬菜品种的多样性，使得害虫种类多，组成变化
大。
• 十字花科蔬菜的连续种植，为害虫提供了充足的
食物来源，使一些害虫呈上升趋势。如小菜蛾和
黄曲条跳甲。
蔬菜地生态系统的特点
3、复种指数高
• 多食性害虫如美洲斑潜蝇和斜纹夜蛾容易发生，
多种害虫同时发 生，造成严重为害。
4、消费者对蔬菜的外观质量要求高，用药频繁。
• 天敌被大量杀伤，天敌群落单一。
5、许多蔬菜直接食用，有些除洗涤外不再加工。
• 在防治上要求高效、低毒。
• 平时采收频繁，天敌不易建立种群 。
三、蔬菜害虫的发生特点
对防治的要求