Agriculture Reference
In-Depth Information
Table 10.3
Yield and fruit weight of tomato, cv. 'Counter', on a split-root system whereby the
two halves were supplied with nutrient solutions of the concentrations indicated. (According to
Sonneveld
2000
)
EC value
Yield (kg m
−2
)
%
Fruit weight (g)
%
2.5/2.5
24.0
100
77
100
5.0/5.0
21.1
88
71
92
2.5/5.0
23.7
99
80
104
Box 2
Fertilizer use efficiency (FUE)
Efficient use of fertilizers has become of economic and environmental
importance in greenhouse production. One can calculate fertilizer use effi-
ciency as the ratio of marketable yield to total fertilizers used. Greenhouse
production can be very intensive and there are great differences between
the fertilizer usage in an open field and the greenhouse. Similarly, the loss
of fertilizer could be drastically reduced, using closed production systems.
Marcelis et al. (
2000
) estimated the data for both, an open and a closed pro-
duction system. They noted that whereas in standard greenhouses in many
Mediterranean countries the yearly losses were approximately 300-350 kg N
and 125-300 kg P, in a “closed loop” greenhouse production system, in north
Europe approximately 120 kg N and 20 kg P per ha and year can be lost. It is
now clear that fertilizer losses can be reduced even further.
yield and product quality. This system is similar to a 'partial root-zone drying'
irrigation system (with the difference that instead of different soil moisture, dif-
ferent osmotic potentials are realized). In this case, the most favorable part of the
root system experienced the largest water absorption, the plant as a whole does
not show any restriction and the yield and fruit weight was nearly the same as in
normal EC-value (Table
10.3
).
Jokinen et al. (
2011
) also reported that the split root fertigation approach pro-
vided complementary benefits over traditional fertigation, in terms of water and
nutrient uptake and ultimately yield improvement. The peat-based split root fertiga-
tion (SRF) method improved cucumber yield in both open (21 %) and semi-closed
(17 %) greenhouse conditions over the traditional fertigation method. This indicates
that the response is governed by root exposure to high sodium chloride concentra-
tions and not by water absorption inefficiency of the roots (Lycoskoufis et al.
2005
).
Moreover, better root aeration (enhancing oxygen supply to root cells) may
considerably enhance salinity tolerance of tomatoes in heavy clay and saline soils
(Bhattarai et al.
2006
).
More detailed information concerning soilless culture apart from Savvas et al.
(
2013
) and Gruda et al. (
2013
), can be found in Resh (
2012
), Savvas and Passam
(
2002
) and Raviv and Lieth (
2008
) and for information concerning plant nutrition
of greenhouse crops, the topic by Sonneveld and Voogt (
2009
) is recommended.
