Biomedical Engineering Reference
In-Depth Information
We suggest: 1) to conduct acidity tolerance tests on nonreactive substrate and replace the
medium every day; 2) introduce into method coefficient of tested plants organ growth
function reduction in stress conditions in comparison with control one.
K
K
K
K
wr
ws
wp
l
K
,
red
4
where average root weight (K
wr
), shoot weight (K
ws
), plant weight (K
wp
) and shoot length (K
l
)
are the particular coefficients of growth reduction result from ratio of average value under
stress conditions to the average value under control ones. The higher coefficient is so more
tolerant the variety is. The parameter of root length was excluded from the method because of
tendency of acidity tolerant varieties to shorten these organs under stress conditions parallel
with increasing of root system branching.
The improved method was used in physiological test of acidity tolerant regenerant
created in Minusa callus culture on selective medium with pH 4,0. That test showed the
technology of
in vitro
selection effectiveness even more clearly than in the tests of salinity
tolerance and confirmed the inheritance of acidity tolerance feature.
The growth activity decrease of regenerant was lower than Minusa plantlets showed
under stress conditions in comparison with control ones, which resulted in coefficients K
red
0,671 and 0,504 respectively (Table 6).
The improved test method allowed retracing the dynamic of growth which showed the
superiority of regenerant over its parental cultivar (Figure 6).
Figure 6. Rate of Minusa and its regenerant plantlets shoot (a) and root (b) elongation under control (1)
and stress (2) conditions (V, mm/day) (Р≤0,05).
Germination rate of regenerant`s root elongation was 1,6 times higher than parental
cultivar one`s under control conditions in second day. This ratio was reached by the eighth
day in variant with pH 3,0. The longer active growth stage of regenerant plantlets than
parental one`s - till the eighth day, under stress conditions was detected. Root growth of
parental cultivar stopped by the fourth day under pH 3,0.
Search WWH ::
Custom Search