Red Spot Fruit Blemish (Freckles)

Xanthomonas arboricola pv. pruni

36 host plants

Last updated

Data Maturity Baseline

This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.

Red spot, fruit blemish, and freckles appear as red discolored areas on fruit surface. These conditions affect marketability of affected fruit. Proper cultural practices and resistant varieties help minimize incidence. Remove affected fruit. Monitor for causal factors. These leaf-spotting diseases are most active in cool, wet conditions. Remove infected foliage and improve air circulation Early detection and prompt management of symptoms help limit disease spread.

Leaf spot and blotch diseases are primarily cosmetic on established plants, though repeated years of heavy infection can weaken them. Rake up and remove fallen leaves to reduce the spore load going into the next season. Avoid overhead watering that splashes spores from the ground onto lower leaves. If the problem is severe, protective fungicide sprays during spring leaf emergence can help, but sanitation does more than chemistry for most leaf spots.

Quick Reference

Causal Agent
Xanthomonas arboricola pv. pruni
Host Plants
36

Management

Cultural Controls

  • Plant resistant varieties when available [VERIFY resistance data for X. arboricola pv. pruni in stone fruit] [VERIFY] PNW Handbook, WSU Extension
  • Avoid overhead irrigation; use drip irrigation or soaker hoses [VERIFY] General Xanthomonas management practice
  • Prune and remove infected branches; sterilize pruning tools between cuts [VERIFY]
  • Apply copper fungicides preventively during bloom and early fruit development [VERIFY] Copper efficacy data and timing for X. arboricola pv. pruni

Host Plants (36)

Prunus americana Wild Plum American (Red) Plum August Plum, Goose Plum Prunus armeniaca Apricot Prunus avium Sweet Cherry Prunus besseyi Sand Cherry, Western Sand Cherry Prunus blireiana Blireiana Plum Prunus caroliniana Carolina Cherrylaurel American Cherrylaurel Prunus cascade Prunus cascade Prunus cerasifera Cherry, Plum Prunus cistena Purpleleaf Sandcherry Redleaf Sandcherry Cistena Sandcherry Cistena Plum Prunus dream Prunus dream Prunus emarginata Bitter Cherry, Wild Cherry, Quinine Cherry Prunus first Prunus first Prunus fruticosa Steppe Cherry, European Dwarf Ground Cherry, Mongolian Cherry Prunus glandulosa Dwarf Flowering Almond Prunus ilicifolia Hollyleaf Cherry, Holly-leaved Cherry Prunus laurocerasus Cherry, Laurel Prunus lusitanica Portugal Laurel Prunus maackii Amur Chokecherry Amur Cherry, Manchurian Cherry Prunus mume Japanese Apricotc Japanese Flowering Apricot Japanese Flowering Plum Prunus newport Newport Flowering Plum Prunus okame Okame Flowering Cherry Prunus padus European Birdcherry Common Birdcherry Prunus prostrata Rock Cherry, Mountain Cherry Prunus sargentii Sargent Cherry, Sargent's Cherry Prunus serotina Black Cherry, Rum Cherry Prunus serrula Birchbark Cherry, Paperbark Cherry, Tibetan Cherry Prunus serrulata Japanese Flowering Cherry Prunus snow Prunus snow Prunus subcordata Klamath Plum, Sierra Plum, Pacific Plum Prunus subhirtella Higan Cherry Prunus subhirtella var. autumnalis Autumn Flowering Higan Cherry Prunus tai Prunus tai Prunus virginiana Prunus virginiana Prunus virginiana var. demissa Western Chokecherry Prunus virginiana var. virginiana Common Chokecherry, Eastern Chokecherry Prunus yedoensis Yoshino Cherry, Somei-yoshino Cherry, Tokyo Cherry

Sources & References

Primary: [VERIFY] PNW Plant Disease Management Handbook, WSU Extension — disease identity uncertain, causal agent corrected from X. citri to X. arboricola pv. pruni