Nepenthes and tissue culture

From: Maciej Hempel (
Date: Fri Jun 11 1999 - 18:43:36 PDT

Date: Sat, 12 Jun 1999 11:43:36 +1000
From: "Maciej Hempel" <>
Message-Id: <aabcdefg2123$foo@default>
Subject: Nepenthes and tissue culture


Last few postings on influence of tissue culture on Nepenthes
prompted me to add these few remarks.

We have been in tissue culture business for nearly 30 years and
propagating hundreds of different plants. For the last four years
or so, we do Nepenthes on contract for one of its growers. We find
propagation of Nepenthes in vitro as not different from that other
plants, i.e. proper media and environmental formulas are needed to
produce good quality plants. It is easier to manage Nepenthes in
vitro than, for example, such standard plants as roses or

As in any other cultivation system, the excess of almost anything
can create physiological disorders. Too much or too little
fertilisation can kill plants. Too much sun or too much shade can
stunt them or etiolate them.

Tissue culture growing/propagation system is not different from
others in this respect. The only difference is that its buffering
capacity is much lower than those of more open systems as soil or
substrate culture. Because media formulas are almost totally under
our control (with only some minute impurities), the response we get
from plants in vitro depends directly on our knowledge of their
reaction to substances added to the media. But this knowledge is
sometimes very limited and lack of understanding of plant reactions
is the direct cause of physiological disorders - not the propagation
system itself.

The main cause of stunning and slow grow after t/c is the use of
unsuitable cytokinin or its use in too high concentration. Some
cytokinins are metabolised by plants faster than others. Some
accumulate in plants and are released later which prolongs their
effects, i.e. inhibition of rooting, induction of branching, on the
post vitro stage of growth. Plant reaction to cytokinins depends
also, between others, on mineral salts, sugar and temperature

It took us almost a year to understand Nepenthes reaction to mineral
salts, sugars, cytokinins, auxins, light and temperature in vitro.
At present, we do not have major problems with its culture. If we
have them, with some new hybrids or species - we know how to deal
with them. We use hormones in vitro but in optimal concentrations.
Customers are satisfied with the quality of our plants and we are
happy to deal with the challenges linked to tissue culture of new
hybrids or species.

To sum up this a little bit long discussion, the advise is:

find a tissue culture laboratory which will take a full
responsibility for the quality of its plants.

Happy growing,

Maciek Hempel

Plant World Explorations

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