A Look At

Stem Rot

Photos & Text Contributed by: Mark Mills

After Mark read 'Help with Wrinkled Cuttings' thread on an online forum, he decided to pull up his slow cuttings and see what was going on. He started with 4 cuttings in Feb. One cutting has 7 or 8 big leaves, but the other 3 have stalled with 'leaf buds' of about 1 inch in length. Above pictured is the base of one cutting. Pretty typical of the three. None of the three had any sign of roots.

 

 

Here is what it looked like after a cut was made. Seeing nasty looking black spots, Mark cut up to the point were the black spots disappeared:

 




 

 

 

 

 

 

 

 

 

 

 

At this point, Mark was wondering if his visual inspection was really picking the end of 'the rot'. So here are the cross-sections up close:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Based on these closeups, he suspected the 'fungus' is traveling up the interior layer of the cutting. Mark feels this layer would provide nutrients from the roots (if there were any). Since there is some transport, the fungus mold is transported up the layer causing the cutting to rot. All three of the cuttings had the same rot at the cutting surface. Mark cut all the cutting to reveal fresh white interiors.

 

Then, Mark sat the cuttings in cups of water on a Sunday. He sprinkled a little Rootone in each cup. The Rootone package said there was a fungicide in it. Tuesday, he looked at the cuttings. Nothing had changed. There was a little latex over each cut. The cuts were still bright white. Mark thought he noticed a few new black spots on the surface of one cutting, so he added about 10 drops of systemic fungicide (undiluted) to each cup. He is waiting the results to see if his Rootone and fungicide treatment stops the stem rot.

_______________________________________________________________________________________

 

Note - Give Mark's method a try. There is a 50/50 success rate with stem rot cuttings. Sometimes they get pretty small - cutting them from 24" down to 6 - 8". Some grow fine and others become affected by stem rot again. Many cuttings that have stem rot will die even after cutting to fresh white pulp. It seems the fungus, although not seen, it still within the cutting. So don't be discouraged if your cutting succumbs to stem rot - and be happy if you can stop it and get your cutting to grow.



Thanks Mark for contributing these great photos and information.

Please click here to go BACK to Valley Of The Sun Plumeria Society 2004.