第四章 植物病原原核生物 Phytopathogenic Prokaryotes（2/2）

Strategies for controlling of GCG 了防治方法：农业防治、物理防治、化学防治 抗病品种（遗传工程）、生物防治 生防菌株：F2/5、MI15、E26

Strategies for controlling of GCG 防治方法：农业防治、物理防治、化学防治 抗病品种（遗传工程）、生物防治 生防菌株：F2/5、MI15、E26

Agrobacterium vitis E26 Isolation:originally isolated from vineyard; Identified as A.vitis according to: Morphology Physiological and Biochemistrical tests 16SrDNA analysis Pathogencity tests:nonpathogenic on grape, sunflower and tomato,etc. Production of antibiotics:producing agrocin active against pathogenic A.vitis in vitro

Agrobacterium vitis E26 • Isolation: originally isolated from vineyard; • Identified as A. vitis according to: - Morphology - Physiological and Biochemistrical tests - 16SrDNA analysis • Pathogencity tests: nonpathogenic on grape, sunflower and tomato, etc. • Production of antibiotics: producing agrocin active against pathogenic A. vitis in vitro

12 菌剂加入等体积的水混匀根部浸泡20至30分钟 324 蘸根处理葡萄苗 经处理的葡萄苗未经处理的葡萄苗

经处理的葡萄苗 未经处理的葡萄苗

A.tumefaciens (Ti plasmid) as genes vectors 口A natural genetic engineer(天然的基因工程师) Strategy -add eukaryotic promoter(真核细胞基因的启动子)to desirable gene(目的基因) eg insecticidal protein of B.thuringiensis insert desirable gene into T-DNA,in Ti plasmid insert plant T-DNA inserts into plant genome-expresses gene

A. tumefaciens (Ti plasmid) as genes vectors  A natural genetic engineer（天然的基因工程师）  Strategy - add eukaryotic promoter（真核细胞基因的启动子） to desirable gene（目的基因） + eg insecticidal protein of B. thuringiensis - insert desirable gene into T-DNA, in Ti plasmid - insert plant → T-DNA inserts into plant genome → expresses gene

2.Erwinia(欧文氏菌属) straight rod-shaped(直杆状) Peritrichous flagella (most)(大多数周生多鞭毛) 6- facultative saprophyte(兼性腐生) Diseases caused Soft rot(软腐)，bacterial wilt（萎蔫)，fire blight(火疫) Symptom rot,leaf spot,wilt

2. Erwinia (欧文氏菌属) • straight rod-shaped(直杆状） • Peritrichous flagella (most)（大多数周生多鞭毛） • G- • facultative saprophyte（兼性腐生） • Diseases caused Soft rot（软腐）, bacterial wilt（萎蔫）, fire blight（火疫） • Symptom rot, leaf spot, wilt

E.carotovora(胡萝卜欧文氏菌) → cabbage soft rot(白菜软腐病) 。 Infects through wound Secreting pectic enzymes( 胶酶)，destructing middle lamella(中胶层)and the cell wal(细胞壁) Overwintering(越冬)in diseased plants or its residues(残体)，composts(堆 肥)and soil Spreading(传播)by insect, rainwater,irrigating and farming activities

E. carotovora ( 胡萝卜欧文氏菌） → cabbage soft rot（白菜软腐病） • Infects through wound • Secreting pectic enzymes (果 胶酶)，destructing middle lamella(中胶层） and the cell wall（细胞壁） • Overwintering（越冬） in diseased plants or its residues (残体), composts(堆 肥) and soil • Spreading（传播） by insect, rainwater, irrigating and farming activities. • Control Strategies

E.tracheiphila (噬维管欧文氏菌)→ cucumber bacterial wilt(黄瓜细菌性萎蔫) survive in sidues stines(肠) Control,7 insect r bundle(维 of a leaf,then hole plant

E. tracheiphila （噬维管欧文氏菌） → cucumber bacterial wilt（黄瓜细菌性萎蔫） • Bacteria hardly survive in diseased plant residues • Overwintering in intestines(肠) of flea beetles(跳甲) • Entering leaf vein with insect feeding • Spreading in vascular bundle(维 管束) • Wilting parts of a leaf, then the whole plant Control？

E.amylovora (噬/解淀粉欧文氏菌)→Fire Blight photo 2-20-K.D.Hickey

E. amylovora （噬/解淀粉欧文氏菌） → Fire Blight

Fire blight ·Symptom-Brown wilt(褐色、枯萎) Most economically important ·Overwintering"holdover"canker(溃疡边缘活组织) Entering blossoms(花)through nectary(蜜腺)with insect feeding or via rain/irrigating through stomas()/wound ·Spreading intercellularly(细胞间隙) ·Transmitting by transportation of seedlings(随苗木调运远 距离传播)

Fire blight • Symptom - Brown wilt(褐色、枯萎） • Most economically important • Overwintering “holdover” canker (溃疡边缘活组织） • Entering blossoms（花） through nectary(蜜腺) with insect feeding or via rain/irrigating through stomas(气孔)/wound • Spreading intercellularly（细胞间隙） • Transmitting by transportation of seedlings（随苗木调运远 距离传播）

Management of Fire blight ·Resistant cultivars Field/orchard/nursery sanitation ·Chemicals antibiotics(抗菌素)-streptomycin(链霉素) ·Biological control avirulent strains of E.amylovora P.fluorescens -site exclusion

Management of Fire blight • Resistant cultivars • Field/orchard/nursery sanitation • Chemicals antibiotics(抗菌素）- streptomycin（链霉素） • Biological control avirulent strains of E. amylovora P. fluorescens -site exclusion