Dr. Phyto

peach

Prunus persica

Diseases & pests on this plant

• peach leaf curlTaphrina deformans

  Newly emerging leaves dramatically thickened, puckered, and reddish-purple in spring, gross distortion + crinkling makes leaves unmistakable, infected leaves drop in May-June leaving tree partially defoliated, second wave of healthy leaves regrows but harvest is reduced 30-80% in heavy years, severe defoliation 2-3 years running can kill young trees.

• Queensland fruit flyBactrocera tryoni

  Small 'sting' punctures on ripening fruit, often with a weeping or dimpled spot; maggots (cream-coloured larvae) tunnel the flesh causing internal rot and premature fruit drop. Adults are wasp-like, reddish-brown flies with clear wings seen resting on foliage and fruit.

• European brown rot / blossom blightMonilinia laxa

  Sudden brown collapse of flower clusters during/just after bloom, dead flower spurs hanging on twigs producing greyish spore masses, twig cankers oozing amber gum below dead blossoms, branch dieback in heavy infections, summer fruit rot identical to M. fructicola.

• Brown marmorated stink bugHalyomorpha halys

  Shield-shaped brown bug ~17 mm with alternating light and dark bands on the antennae and abdomen edge; feeding causes corky, dimpled, cat-faced distortion on tree fruit, cloudy or necrotic spots on peppers and tomatoes, and shrivelled pods on soybean. Adults gather on and enter buildings to overwinter.

• American brown rot of stone fruitMonilinia fructicola

  Soft brown rotting patches on ripening + ripe fruit, characteristic tan-colored powdery spore tufts on rot surface, fruit shrivels into hard black mummy and stays attached to twig, blossom blight in spring (entire flower spurs collapsing), gummosis + cankers at base of infected twigs.

• red-necked longhorn beetleAromia bungiiEU-notifiable quarantine organism

  A large black longhorn beetle with a bright red-orange patch on the thorax (pronotum) and very long antennae; the larvae bore long tunnels in the trunk and main branches of stone-fruit trees (peach, cherry, plum, apricot), pushing out coarse fibrous frass and sawdust from cracks at the base; branches wilt, the tree declines and can be girdled and killed.

• powdery mildew of peach + roseSphaerotheca pannosa

  White powdery patches on young leaves + shoot tips, distorted + cupped young foliage, white powdery patches on developing fruit later hardening into rough corky russet, susceptible cultivars can have entire fruit surface covered, premature shoot tip dieback.

• Light brown apple mothEpiphyas postvittana

  Leafroller caterpillars web leaves together and to fruit with silk, feeding within the shelter; surface chewing and shallow 'scribble' scarring on fruit near the calyx or where leaves touch. Small light-brown moths rest with a bell-shaped wing profile.

• oriental fruit flyBactrocera dorsalisEU-notifiable quarantine organism

  The female stings ripening fruit (citrus, peach, many hosts) and lays eggs under the skin; maggots tunnel the flesh, which softens, browns and rots from the inside while the outside may look only slightly blemished with small puncture marks; infested fruit drop early. The adult is a wasp-like fly with a mostly dark abdomen and clear wings.

• Japanese beetlePopillia japonicaEU-notifiable quarantine organism

  Adults are bright metallic green with coppery wing-cases and small white tufts of hair along the sides of the abdomen; they feed in groups in sunshine, skeletonising leaves between the veins (a lacy look) and chewing flowers and fruit of a huge range of plants (rose, grape, lime, fruit, soft fruit); the white C-shaped grubs eat grass roots, causing brown patches of lawn that lift like a carpet.

• bacterial spot of stone fruitXanthomonas arboricola pv. pruniEU-notifiable quarantine organism

  Angular water-soaked spots on leaves with yellow halos, dark sunken pits + cracks on fruit (looks like shothole), twig cankers oozing amber bacterial slime in spring, premature leaf drop + defoliation, fruit becomes unmarketable due to cosmetic damage and acts as inoculum reservoir.

• Sharka (plum pox)Plum Pox Virus

  Light-green to yellow rings + chlorotic spots on leaves (the diagnostic pox), ringspot deformations on fruit surface, sunken brown areas on plum + apricot fruit flesh making it inedible, premature fruit drop, gradual yield decline over 3-5 years until tree must be removed, symptoms vary heavily by cultivar + strain — confirmation requires lab ELISA test.