APPLE DISEASES

SAJAD UN NABI

BY

INTRODUCTION

Botanical name: Malus domesticaFamily: Rosaceae

Production: 76.51 Mt (world)2891 met tonnes( India)

Productivity: 14.36 MT/Ha (World)10.1 MT/Ha (India)

India is the 5th largest producer of apple in world grown in J&K, Himachal pradesh, Uttrakhand

Jammu and Kashmir is largest producer (64.5%) of apple in India followed by Himachal pradesh (30.1%)

DISEASES

FUNGALApple ScabRoot rotCollar rot Powder mildewSooty blotch and Fly speckCankerBlue mold

BACTERIAL Fire Blight Gall formation

VIRAL Apple mosaic Apple stem pitting Apple stem grooving Apple chlorotic leaf spot

VIROID Apple scar skin

PHYTOPLSMAL Apple proliferation

FUNGAL DISEASES

APPLE SCAB (Venturia inaequalis)

First reported in Swedan and in India from Kashmir valley on cultivar Ambri

Epidemic in Kashmir valley in 1975 and in Himachal Pradesh in 1981

Among five diseases of national importance having domestic Quarantine

SYMPTOMSLeaf - Valvety olive green lesions with indistinct margins are observed that are turn metallic black

Fruit Scabs - fungus stimulates cork formation beneath spots that may cover the fruits and result in severe fruit disfiguration

Twigs – infections easily overlooked as the lesions look like enlarged lenticels

LIFE CYCLE

Management

Resistant varietiesShreen , Firdous, Akbar, Freedom, Belmac, Redfree, Prima SanitationRemoval of last year leaves, infected fruits to Prevent pseudothcialformation in overwintering apple leaves.

Biological controlTrichoderma :Reduction of conidia productionMicrosphaeropsis ochraceae: Potent bio-sanitation agent againstapple scab as this fungus kills the resting structures of V. inaequalis

Chemical control• Protectant fungicdes are applied routinely at 7 to 10 day intervals

according to anticipated infection periods( Baycor @ 0.5%, Dodine@0.6%) at pink bud stage

• Application of urea on fallen leaves @ 0.14%

APPLE CANKERS

CANKER NAME CAUSAL ORGANISM

Black /Brown Sphaeropsis malorum

Pink canker Corticium salmonicolor

Valsa canker Valsa ceratosperma

Eurapean canker Nectria galligena

Nail Head canker Numullaria discreta

Phomopsis canker Phomopsis mali

SYMPTOMS

•Girdling of branches and die back or twig blight

• Mumified ,rotting of fruit and Premature defoliation.

MANAGEMENT

•Avoid mechanical injury and apply wounddressers on cut areas

•Orchard sanitation

•Canker girdled branches should be removedalongwith 15cm healthy tissue in dormantseason or 30cm in growing season

•Partially girdled branches should be scarifiedwith sharp knife and covered with chaubhattia orbordeaux paste

MUMMIFIED FRUITS

WHITE ROOT ROT (Rosellina necatrix)

SYMPTOMS Initially yellowing of leaves Affected plant bear small leaves less in number & profuse fruitingFishy smell from exposed rootsIn sever cases plant dies

MANAGEMENTAvoid water logging Removal of soil from canopy up to depth of 6-9 inch Drenching with carbendiazim @ 0.1% + captan @0.2 % in 2 inch diameter, 12- 18inch deep holes in alternate lines around the canopy area up to 2 meter width Soil sterilization with 3% formaldehyde

COLLAR ROT (Phtophthora cactorum)

Above Ground Symptoms

o Undersize and stunted leaves.o Ample fruiting

Below Ground Symptoms

o Bark at the soil line becomes slimy and rots results in cankered areas.o Wounds are irregular in outline usually rough,oval,which extend rapidly girdling of a tree.

MANAGEMENTCultural Control:Improved drainage.Chemical Control:After scarification application of Bordeaux paste or metalaxyl paint.DrenchingI. Mancozeb 75 WP @0.3%.II. Metalaxyl MZ 72 WP @0.2%

SOOTY BLOTCH AND FLY SPECK

SYMPTOMSSooty blotch (Gloedes pomigena)Brown to dull black, sooty blotches form on the fruitsurface.The fungus is restricted to the outer surface of the fruit,and in many cases the blotches can be easily rubbed off.

Fly speck (Schizothyrium pomi)Groups of 6 to 50 or more black and shiny round dotsappear on the surface of the fruit. Like sooty blotch, flyspeck infections are superficial; however, they areusually harder to rub off than sooty blotch

MANAGEMENT Avoid shade trees around orchards

Proper prunning and training

Use of protective fungicides like Mancozeb @ 0.5 %

BLUE MOLD (Penicillium digitatum)

Affect mature fruit only (Post harvest disease) Common rot of stored apples and pears SYMPTOMSWatery areas that begin around injuries or lenticels on the fruit surface

Characteristically moldy odour and flavor

Grayish-blue masses of spores appear on the fruit surface

MANAGEMENT Avoid wounds and bruises during harvesting,

packing And storage Harvested at optimum maturity Disinfection of containers etc Remove decaying fruit daily from

packinghouses Postharvest chemical treatments( Benlate)

BACTERIAL DISEASES

FIRE BLIGHT( Erwinia amylovora)

First bacterial disease reportedby T.J.Burill in 1878

Not present in India

SYMPTOMS

• Flower and twig – blightappears in spring, blackening offlowers and leaves = curledleaves hanging from twigs andsmall branches

• Fruits – first as water soakedlesion, then mummifies andturn black and may remain ontree for several months

DISEASE CYCLE

MANAGEMENT

• Pruning

– Prune out blighted twigs and cankers during the dormantseason. This may decrease the pathogen inoculum level for thefollowing season.

– If blighted twigs are pruned out during summer, cuts should bemade l2 to l5 inches below diseased wood and pruning toolsshould be disinfested by dipping in a 2:10 solution ofhousehold bleach in water after each cut.

• Proper fertilization

– Excessive nitrogen fertilizer and heavy pruning will promotevigorous growth of succulent tissue which is more susceptibleto fire blight. Avoid excessive use of nitrogen fertilizer andapply fertilizer only in the spring.

• Control insects

– Sucking insects create wounds through which fire blightbacteria can enter.

CROWN GALL (Agrobacterium tumefaciens)

SYMPTOMSIdentified by over growthsappearing as galls on roots and atthe base or "crown" of apple &pear)MANAGEMENTSite selection. Fields that havegrown cereal crops for a long periodare favored as crown gall-free sites.Chemical eradicants. Creosote-based compounds, copper-basedsolutions, and strong oxidants suchas sodium hypochlorite aretransiently effectiveBiological control. Use of A.radiobacter K84 before planting ininfested field

VIRAL AND VIROID DISEASES

APPLE MOSAIC (AMV)

Illarvirus (Apple mosaic virus)Transmission: Pollen

SYMPTOMSBright cream spots on spring leaves as they expand , These spots may become necrotic after exposure to summer sun and heat

MANAGEMENT Avoiding taking graft wood or bud

wood from infected tree

For checking the spread of disease through root grafting, trench should be dug around the trunk of infected tree

Resistant varieties if available

APPLE STEM PITTING (ASPV)

Foveavirus (Apple stem pitting virus)Transmission: Grafting

SYMPTOMS Inner bark necrosis, dieback, vein

yellowing

MANAGEMENTAvoiding taking graft wood or bud

wood from infected tree

APPLE SCAR SKIN (ASSVd)

APSCAVIROID

SYMPTOMS

Reddish brown patches with brownish scar-liketissue, dappling(spotting)

Infected fruits often remain small and hard,do not ripen properly, and develop anunpleasant off-flavour

MANAGEMENT Use of healthy propagation materials

Indexing programmes

if necessary, the removal of diseased trees.

PHYTOPLASMA DISEASES

APPLE PROLIFERATION(APP)

Causal Organism: Phytoplasma maliSYMPTOMSBranchesWitches' broom: The development of axillary buds produces a proliferation of secondaryshoots, which creates a broom-like appearance at the end of the affected branchLeavesLeaves may roll downwards and become brittle, finely and irregularly serrated, are smaller than normal and may appear more yellow than healthy leaves during the summerMANAGEMENTRemoval of infected trees and the control of insect vectors may limit the spread of APPAPP-resistant rootstocks