97
of water stress under field conditions had inhibited vegetative growth but enhanced
fruit development.
The influence of water stress on tomato plants and fruit quality was investigated
by Nahar and Gretzmacher (2002). They reported that yield and dry matter production of tomato were adversely affected under application of 40% of the field capacity. Furthermore, Nuruddin (2001) indicated that water stress throughout the
growing season significantly reduced yield of tomato and fruit size, but plants
stressed only during flowering showed fewer but bigger fruits than completely nonstressed plants. Under water stress conditions, Claussen (2005) found that proline
content rise, as early as in 14 h after water stress. Pokluda et al. (2010) indicated that
water stress reduced specific leaf area and leaf water content and increase leaf proline concentration in tomato. Reduction in leaf water potential content was also
reported by Kirnak et al. (2001) as a result of soil moisture stress, which in turn may
reduce transpiration. They also added that specific leaf area and leaf water content
were good indicators of water stress in tomato, and proline content was a reliable
parameter corresponding to the actual water stress of plants.
5.3.2 Effect of Deficit Irrigation on Winter Tomato
Shalaby et al. (2014) studied the effect of application of deficit irrigation to tomato
grown under drip system in calcareous soil. They indicated that saving 25% of the
applied irrigation water resulted in 9% yield losses. Furthermore, application of
80% of full irrigation to tomato grown in clay loam soil under subsurface drip system resulted in 15% yield losses (Abdelhady et al. 2017). Additionally, Kamal and
El-Shazly (2013) reported that 7% losses in tomato yield grown under drip system
in calcareous soil occurred when 75% of full irrigation was applied.
5.3.3 Irrigation Water Saving Techniques for Winter Tomato
5.3.3.1 Traditional Cultivation of Winter Tomato
Table 5.8 indicated that the highest cultivated area of winter tomato in Lower Egypt
existed in Sharkia governorate, i.e. 9.0 thousand hectares in the old lands. In Middle,
the highest cultivated area existed in Fayoum and Minia governorates, namely 1.6
thousand hectares, respectively. In Upper Egypt, the highest cultivated area existed
in Sohag, namely 1.5 thousand hectares. In the new lands, the highest cultivated
area existed in Behira governorate in Lower Egypt, i.e. 11.0 thousand hectares.
Similarly, the highest cultivated area in Middle and Upper Egypt were found in both
Beni Sweif and Sohag governorates, namely 3.2 thousand hectares.
The total cultivated area of winter tomato in the old and new lands were 28.3 and
42.1 thousand hectares, respectively. These areas produced 1338.2 and 1780.9
5 Vegetable Crops and Deficit Irrigation in Egypt
of water stress under field conditions had inhibited vegetative growth but enhanced
fruit development.
The influence of water stress on tomato plants and fruit quality was investigated
by Nahar and Gretzmacher (2002). They reported that yield and dry matter production of tomato were adversely affected under application of 40% of the field capacity. Furthermore, Nuruddin (2001) indicated that water stress throughout the
growing season significantly reduced yield of tomato and fruit size, but plants
stressed only during flowering showed fewer but bigger fruits than completely nonstressed plants. Under water stress conditions, Claussen (2005) found that proline
content rise, as early as in 14 h after water stress. Pokluda et al. (2010) indicated that
water stress reduced specific leaf area and leaf water content and increase leaf proline concentration in tomato. Reduction in leaf water potential content was also
reported by Kirnak et al. (2001) as a result of soil moisture stress, which in turn may
reduce transpiration. They also added that specific leaf area and leaf water content
were good indicators of water stress in tomato, and proline content was a reliable
parameter corresponding to the actual water stress of plants.
5.3.2 Effect of Deficit Irrigation on Winter Tomato
Shalaby et al. (2014) studied the effect of application of deficit irrigation to tomato
grown under drip system in calcareous soil. They indicated that saving 25% of the
applied irrigation water resulted in 9% yield losses. Furthermore, application of
80% of full irrigation to tomato grown in clay loam soil under subsurface drip system resulted in 15% yield losses (Abdelhady et al. 2017). Additionally, Kamal and
El-Shazly (2013) reported that 7% losses in tomato yield grown under drip system
in calcareous soil occurred when 75% of full irrigation was applied.
5.3.3 Irrigation Water Saving Techniques for Winter Tomato
5.3.3.1 Traditional Cultivation of Winter Tomato
Table 5.8 indicated that the highest cultivated area of winter tomato in Lower Egypt
existed in Sharkia governorate, i.e. 9.0 thousand hectares in the old lands. In Middle,
the highest cultivated area existed in Fayoum and Minia governorates, namely 1.6
thousand hectares, respectively. In Upper Egypt, the highest cultivated area existed
in Sohag, namely 1.5 thousand hectares. In the new lands, the highest cultivated
area existed in Behira governorate in Lower Egypt, i.e. 11.0 thousand hectares.
Similarly, the highest cultivated area in Middle and Upper Egypt were found in both
Beni Sweif and Sohag governorates, namely 3.2 thousand hectares.
The total cultivated area of winter tomato in the old and new lands were 28.3 and
42.1 thousand hectares, respectively. These areas produced 1338.2 and 1780.9
5 Vegetable Crops and Deficit Irrigation in Egypt