I would go with your first guess, it is a salt, or nutrient imbalance.  I do not know the containers you refereed to by name, but it is not a classic ethylene respone.

By the way, Bob Head was here yesterday talking about you and Teddy Bear.  He said your about the only one who does well, but we should make it better.  I told him to talk to Leo at Windy Hill about getting some sort of joint project.

Take care

Thanks Jeff

I hope the project gets up with Bob and Leo as the Teddy Bears are not the fastest beasts. 

Regarding the raspberry, thank you for the thought back up.  The containers are just normal chinese food containers which do not have a lot of gas exchange.

Is is possible to re-engineer media? The client is sending me a tub with the old media next week, the reason being I wanted to isolate whether we had caused a salt issue with the deflasking media.  

The only problem  with re engineering is I suspect this has happened when they were subcultured and a time lapse of 4 weeks has passed with changes in the media according to plant development.

Rescue is now my focus.

Cheers

Right.  a before and after medium sample would be what you need  Has Barbara Reed published her revsised raspberry medium paper yet.  I know she did the work and has just retired.

Not to my knowledge, Barbara had quite a few papers that she was working on when I visited a few months ago. I suspect she will tick off the long list before year end. There was some exciting work being carried out

Dear, I can not comment on this issue until I know what stage were cultures at receiving - on the proliferation, rooting or elongation medium, etc. What concerns splitting of meristems I am sending a proper literature. Generally, it is due to  excess of cytokinins, to many subcultures, to strong salt concentration. I don't think it is the reason of the failure. Do all shoots had the same disaster? Do they have roots after dessication?

Sorry that I can not answer simply, Teresa

Dear Teresa

I am receiving plantlets which have been placed on rooting medium for at least four weeks.  I am nearly at 80% loss rate after week four and still going down in numbers.

We have our own raspberry tissue culture which was planted at the same time in the same cocopeat, peat media and these are now with roots and producing leaflet 6 which are quite fat.  We usually note some root development at week 1 with excellent root development by week 3.

The dessicated plants have no root development at all. The failure appears to be an 'open door' like wound in a few places on the original explant stem which is allowing entry for any microbes that is in the environment.  I figured that the error did not show in culture as the media and the environment was sterile, this changed upon deflasking.

So in effect if the plant roots successfully ( this has occurred with about 3%) they settle and start performing very nicely.  It would appear that the plant is fighting off the microbial attack while waiting for back up roots and when they do not appear, they give up the ghost so to speak.

Your literature will be most helpful as the few plants that are left I am attempting to rescue by cutting the plant above the problem area and re dipping in hormone and placing on sterile perlite, vermiculite with 1/2 strength liquid culture media and IBA with a sealed but vented container.  

Dear Karen,

In my opinion there are 3 possible reasons:

1. Microshoots were poisoned during in vitro culture by mistaken medium e.g.  to high levels of growth regulators, which prevented proper conducting tissue for example due to vitrification, and root primordia are forming in these area . Pity that you did not check  cross-section of the stems compairing them with those of your own cultures. But who knew? 

2. Cultures are contaminated by endogenous microbes, non-cultivable maybe, that prevent rooting due to realisation of their own metabolism.

3. Cultures have been prepared for sell to hide contamination and therefore to the medium were included bactericidal preparations - antibiotics or other biocides, which soured the explants.

I hope that amount (and money) you lost were not huge.

Any good news??

Greetings, Teresa

 Thank you all for the valuable answers.

I have managed to get the customer to check her stock solution of IBA and it would appear that human error may be involved hence causing part of the issue.

It now appears that they add extra agar to ensure that everything holds together whilst in transit with the postage system.  The realization that this then changes the matrix of water availability was not considered.  

Her plants are going to her nursery in vented containers and there is a 30-40% loss occurring against our 80% loss.  This statistic lead me to think that there is definitely a link with ethylene.  In desperation we soaked one batch of plants in 1500ppm IBA for 20 minutes completely and the loss rate on this table is about 25%.  So in effect once they produce roots they are capable of withstanding the rigour of life.

I really appreciated your instant answers Teresa and Jeff, and papers Teresa, as this has given us huge assistance in working with the customer and keeping a working relationship for the future. 

The good news you asked for Teresa, will be if I can save what is left as this is a contract just under $100K for the next couple of years at least.