BLACK ROT: Leads Go Black, Leaves Change to Lighter Color and Wrinkle; Pseudobulbs Wrinkle and Show Brown Patches

Ailments Orchid Doctor

by Robert M. [Bert] Hamilton (Compiler)

Originally published in The Orchid Doctor in 1980 and 1988

Posted by Sys Admin almost 7 years ago.

Article Blog   Article Index
Truban is effective; cut off all diseased parts; plunge all into solution 1 tpg. A74-1062
Share on Social Media:  
Log in to Add a Comment

More The Orchid Doctor Articles under the Heading Black Rot

Black Rot Comments
BLACK ROT: Caused by Fungi Pythium ultimum and Phytophora cactorum Most destructive to cattleya-types; worst during cool months; purplish brown area on leaf or root and rhizome and upward into pseudobulbs; drench with Truban 1/2 tpg. AH16 0
BLACK ROT: Fungicide as Preventive Dexon-35 can be so used; also, Truban; packages are commercial size, try to obtain from a commercial grower. A74-896 0
BLACK ROT: In New Leads of Potinara; Benlate and Natriphene Did Not Control Use 1/2 tpg. drench of either Dexon-35, Truban, Terrazole or Banrot; commercial greenhouses may sell a few spoonfuls of one of them. A75-500 0
BLACK ROT: Leaves on Cattleyas Develop Black Spot At Top, Eventually Killing Leaf and Sheath Use Dexon-35 or Truban, 1 tpg. as an overall drench, or soak for 20 to 30 minutes; repeat in 14 days. A72-905; A79-1112 0
BLACK ROT: On Cattleyas Control with Truban or Dexon-35; Truban is gaining favor over Dexon-35; drench or soak in 1 tpg. A72-341; A75-680; A79-1112; use Tersan or Fermate. S198 0
BLACK ROT: On One-inch New Growths This indicates a root disease; dip in Banrot solution ltpg., before repotting; another fungicide to try is Subdue, which may be effective. A81-393; RMH 0
BLACK ROT: On Specimen Cattleya; Benlate Does Not Cure Black rot is not cured by Benlate, use Dexon-35, 1 tpg. soak for 20 minutes. A74-217 0
BLACK ROT: Phytophora Cactorum Leaf and heart rot; cattleyas are the main host; fungus attacks all parts except roots; shows purple, purplish brown or black; leaves often become brittle and can be jarred off; caused by coolness and high humidity; cure must include introducing agent inside plant tissue; use Natriphene dip for 60 minutes, or Dexon 70%, or Thiram 75% (Tersan) WP, at rates given for 100 gallons; repeat in one month; Physan and Shield are good for seedlings; avoid overhead watering. B7; BU8+ 0
BLACK ROT: Pythium Sp. of Fungi On cattleyas; cut rot away ruthlessly; burn the compost; immerse plant in Orthocide captan at 1 teaspoon to 1 pint water for one hour. OR76-99 0
BLACK ROT: Pythium Ultimum Most destructive of cattleyas, others are susceptible; similar symptoms to Phytophora cactorum; small water-soaked spots, later turn purplish black; yellow margin advances; spread quite rapid, 2 or 3 inches per day; often following dividing of plants; spread by splashing; dip for 60 minutes in Natriphene; use Tersan as preventive. B9; BU10; OR74-234 1
BLACK ROT: Tips of New Cattleyas Turn Brown Caused by a fungus; remove all infected growth; soak pot and plant in 1/2 tpg. Dexon-35 or Benlate. A72-686; F69-94 0
BLACK ROT: Treatment with Dexon Remove diseased parts; soak or drench pot in one teaspoon per two gallons water three or four times at 10 to 14 day intervals; it is surface effective only. A74-969 0
BLACK ROT: Two Kinds Are Prevalent One is a cool-weather rot, the other is a warm-weather type and both cause blackening of leaf tissue; both are contagious and can be spread by splashing water; keep plants dry, spray with Benlate; the summer type can destroy a plant in three days, in some areas. OR85-69; F81-17 0
BLACK ROT: Water Mold Pythium Ultimum Is the Cause The special enemy of commumity pots of seedlings; damp-off; spray with Physan, Anti-Damp, or Natriphene once a month as preventive; on mature plants cut out rot; soak plant in good fungicide, dry, treat with Tersan; illus. A66-399+; A73-811 0

New Topics

  1. Nancy Shapiro asked question Where did you find this type of orchid pot? in category General Discussion
  2. Charles H Wood asked question Orchids wanted St.Croix usvi in category General Discussion
  3. William Gorski asked question Is this a species or Primary Hybrid? in category General Discussion
  4. Therese Stecher asked question Banrot 40WP in category General Discussion
  5. Chen Jimmy asked question How to determine the species composition？ in category General Discussion
Ask a Question

Start a Topic

New Comments

  1. Carol Holdren commented on topic "What is the culture for Cattliante Chongkolnee" by Mike Minney
  2. Dianne Mayne commented on topic "Banrot 40WP" by Therese Stecher
  3. Linda Thorne commented on member plant Paphiopedilum Munchkin Mopsi Aru by Linda Thorne
  4. Carol Holdren commented on topic "Orchids wanted St.Croix usvi" by Charles H Wood
  5. William Gorski commented on topic "Is this a species or Primary Hybrid?" by William Gorski
  6. Henry Shaw commented on member plant Coel. Jannine Banks 'Snow White' by Henry Shaw
  7. Carol Holdren commented on topic "Trichocentrum luridum" by Danny Lyon
  8. Carol Holdren commented on topic "How to determine the species composition？" by Chen Jimmy
  9. Lois Lane commented on member plant Ctna. Why Not by Alex Maximiano
  10. Carol Holdren commented on topic "SSPECIES OF ORCHID" by JENNIFER CHARMAN
  11. Carol Holdren commented on topic "Why can't I post on this site? " by Lois Lane
  12. Carol Holdren commented on topic "Historic Cattleya" by Karen Johansen
  13. Carol Holdren commented on topic "Encyclia aspera" by William Woodcock
  14. Jim McGuinn commented on topic "Designing a greenhouse for orchid growing" by Ron Hellendall
  15. Mark Bennett commented on member plant Sarcochilus Newbold Alta 'SBC092' by Mark Bennett
  16. Mark Bennett commented on member plant Sarcochilus Newbold High Noon 'SB140' by Mark Bennett
  17. Carol Holdren commented on orchid Epi. Moonlight Firefies
  18. Jeanne Uzar Hudson commented on topic "Paph Support" by Nicholas Levendosky
  19. Rosemary Chenery commented on topic "Lost tag - can anyone provide a name" by Rosemary Chenery
  20. Taylor Savage commented on topic "Myrmecatavola Frances Fox" by Elizabeth Wagner