| Summary: | 碩士 === 國立臺灣大學 === 園藝學系研究所 === 85 === Light, moderate and severe pruning were applied on 20-year-old waxapple
plants after harvest on late Feburary, 1995 to study the effect of pruning
on vegetative and reproductive growth. The ability of
sprouting , the frequency
of flushing, or the flush number on each node was increased with enhancing
pruning severity. Severe pruning resulted in more new flushes
with shorter stems
and smaller leaves. Accompanying with flushing or new shoot growth, leaf area
index and light interception increased to their maximum values in late August.
Severe pruning owned the least values in the early season but reached same
level as moderate or light pruning in August. After the flower
forcing treatment,
i.e., trunk girdling and partial defoliation, high percentage of inflorescences
formed on all treated plants. Most of the inflorescences were transformed
from the shoot apex on the first flushes which sprouted after pruning. Some
inflorescences transformed from the terminal or lateral parts of one-year-old
lateral shoots of moderately or lightly pruned plants. These results suggested
that pruning influenced sprouting, flushing, morphology of flush, and light
interception but nil on flowering capability.In the view-point
of flush management,
moderate pruning was recommended for waxapple after harvest.
Three-year old potted waxapple plants were introduced into
the phytotron with
different day/night temperature（35/25,30/20 and 25/15℃）to investigate the
influence of temperature on shoot growth and flowering.The time required for
flush growing to maximal stem length,leaf area and chlorophyll
content was shortened
with increasing temperature.For an individual flush,plants
under low temperature
25/15℃）exhibited the highest shoot length,shoot diameter and single leaf
area. On the other hand, plants under highesst temperature(35/25℃)had the
highest frequency of flushing, highest total shoot growth and largest canopy.
The percentage of inflorescence formations was highest under 35/25℃ and
lowest under 25/15℃. No significant difference on diurnal leaf water potential
was noted among different treatments. Starch concentration in the stem and
leaves was higher whereas soluble sugar concentration was lower
at low temperature
than those at high temperature. The relations among temperature, shoot growth,
carbohydrate levels and flowering were discussed.
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