Agriculture Reference
In-Depth Information
Table 19.5
Effect of Pre-Treatments with Auxin
(Naphthalene Acetic Acid, NAA) versus STS on
Relative Fresh Weight, Visual Appearance Scores
(1
Table 19.7
Vase Life at 23°C of Cut Sweet Pea
Florets and Spikes Held in Sucrose with or
without Pre-treatment with STS.
Vase life (days)
=
Excellent, 3
=
Good, 5
=
Fair, 7
=
Poor, 9
=
Very Poor) and Vase Life of Cut Flowering
Geraldton Waxflower Stems Exposed to 5.6
μ
l
Treatment
Florets
Spike
Ethylene/l for 24 h on Day 0.
water (control)
1.7
2.5
Weight
(% initial)
Appearance
score
Vase life
(days)
sucrose (100 g/l)
3.0
5.9
Treatment
STS (0.2 mM)
4.4
7.2
Control
50.8
8.8
1.0
STS
+
sucrose
6.0
8.7
4 mM STS,
15 min pulse
94.9
2.4
5.4
Source: Compiled from Ichimura (1998).
0.5 mM STS,
overnight pulse
100.3
1.2
7.4
40 μg NAA/ml,
30 sec dip
59.8
7.2
1.0
hard green lumps that distort lily petals when they grow
and expand. Thus, insects and diseases affecting cut
flowers should be controlled prior to harvest. In the
context of international trade, post-harvest infestations
can constitute a quarantine problem (Figure 19.6). With a
view to managing resistance, alternating use of active
ingredients from different chemical families should be
practised prior to harvest. Another chemical from a
different group can be reserved for post-harvest treatment.
Adherence to the principles of integrated pest (and
disease) management will reduce reliance upon chemicals
(Hansen & Hara 1994; Flint & Gouveia 2001). Pre-harvest
adoption of biological control measures (e.g.
Trichoderma
for botrytis management) merits consideration (Elad
et al
. 1993). Use of packaging materials and methods
and handling conditions that allow ventilation, minimise
the risk of condensation and maintain low temperature
will assist in post-harvest disease management (Hammer &
Marois 1989; van der Sman
et al
. 1996; Taylor
et al
.
1997, 2001).
Source: Compiled from Joyce (1989).
Table 19.6
Effects of Pre-treatments with STS
and the PGRs NAA, Gibberellic Acid (GA
3
) and
Benzyladenine (BA; Cytokinin) on the Vase Life
(Days) of Cut Goldenrod
Solidago
cv. Yellow
Submarine Stems.
Inflorescence
vase life (days)
Foliage vase
life (days)
Treatment
Control
9.7
6.0
STS (200 μM)
13.3
11.0
NAA (200 μM)
9.8
7.4
GA
3
(100 μM
8.5
7.2
BA (10 μM)
9.8
8.2
STS + BA
13.7
15.0
GA
3
+ BA
7.8
10.5
Insects
Control of insect levels during production is the best way to
reduce post-harvest insect problems. Post-harvest
infestations can be removed manually, such as in the course
of a detergent wash (Seaton & Joyce 1988; Hansen & Hara
1994). Chemical control is effected by dips and sprays with
either insect specific or broad spectrum insecticides, such
as dimethoate and deltamethrin (Seaton & Joyce 1988;
Hansen & Hara 1994; Figure 19.8). Certain insecticides, for
example synthetic pyrethrins, can be applied in aerosol
form. However, complete coverage of the surfaces of
bunched flowers may be difficult to achieve. In contrast, gas
fumigants like methyl bromide and phosphine can be
extremely effective, but the risk of phytotoxicity demands
Source: Compiled from Philosoph-Hadas
et al
. (1996b).
can increase the vase life of some roses (Goszczynska
et al
. 1990).
There is a broad range of other pre-treatments that have
been researched, including nitric oxide (Lesham 2000).
For more information, see Halevy and Mayak (1981), Nell
and Reid (2000) and Reid (2004).
Pest and disease management treatments
Early pest infestation (e.g. mites) or pathogen infection
(e.g. botrytis) can result in malformed flowers. For
example, pre-harvest infection with botrytis can result in
