Agriculture Reference
In-Depth Information
A tent for SH was developed by Stapleton (2000) as a method of eradicating
phytoparasitic pests in closed horticultural applications (Stapleton, 2000; Stapleton
et al.,
2002). Disinfestation is accomplished via heating, the latter induced by covering with a
greenhouse structure; a double-layer tent can be created to increase heating effi cacy. The
soil is either mulched or left bare, and this type of application can be used to disinfest
the soil inside the structure or in container media. The temperature inside the tent rises to
above 70°C, a level of heat which, even if applied for only a short time, can completely
eradicate both phytoparasitic and free-living nematodes. This application of solarization
could potentially come into common use, particularly in developing countries, for disin-
festing soil seedbeds, containerized planting media, and cold-frames in small and simple
structures. These are ideal niches for solarization, since the individual areas to be treated
are small, soil temperature can be greatly increased, the cost of application is low, the
period of solarization is short, and the value of the plants produced is high. Note that the
production of disease-free planting stock is critical for producing healthy crops.
Unlike soil treatment, solarization of structures aims to control the inoculum which
is left within the greenhouse or any other structure and its structural components (the
structure itself, irrigation lines, wires, etc.), which might be contaminated with inoculum
(Gamliel
et al.,
1996
)
. This is achieved by closing the greenhouse during the summer
time, thereby elevating the temperatures (dry heating) to 60, and even close to 70
o
C
(Figure 10.5). Structural solarization is carried out under dry conditions and is considered
solar sanitation (Shlevin
et al.,
2003).
Other special solarization techniques involve: SH in existing, perennial crops such
as pistachio (Ashworth
et al.,
1982) and olive (Tjamos
et al.,
1991), disinfestation of
wooden tomato stakes of
Didymella lycopersici
(Besri & Diop, 1985), solarization of
soils in 40-cm high piles, which was effective in controlling root knot nematodes in olive
nurseries in Spain (Nico
et al.,
2003), and using solar collectors for soil disinfestation
(Ghini, 1993). SH is the only method for soil disinfestation that can be used in organic
farming (CDFA, 2004). Indeed SH is used by farmers practicing organic methods.
Air
Soil 10 cm
Soil 20 cm
Ambient
60
50
40
30
20
07:00
19:00
07:00
19:00
07:00
19:00
Hour
Figure 10.5
Soil and air temperatures during solarization of closed greenhouse during the summer time
in Israel (for structural solarization), compared to ambient air temperature.
