Diseases and Management of Crops under Protected Cultivation

light soil
P total
(Diseases and Management of Crops under Protected Cultivation)
x (1.3-2.2) – depends on pH and soil type. It increases from light to
heavy textured soil and also increases as pH increases (5-8)
K exported x 1.4
texture.
- depends on soil type, it decreases from low to heavy
‣ Method of application : Surface, sprinkler and micro irrigation
‣ Choice of fertilizers
: Granular and liquid
‣ Timing and quantity to apply : Growth curve based fertilizer requirement and scheduling
6. Fertilizer Use Efficiency (FUE) under Drip-fertigation
Fertigation facilitates the application of water and nutrients directly into the plant root zone,
leading to greater efficiencies of application and uptake. This has been substantiated for various
crops in studies carried out across the world. Goel, 2007 reported that fertilizer use efficiency of
nitrogen is as high as 95% under drip-fertigation as compared to 30-50% under soil application (
Table 3).The results of studies carried out on sugarcane in Maurititus (Ng Kee Kwong et. Al.,
1999) and Australia (Dart et al., 2000; Ridge and Hewson, 1995), indicated increase in nitrogen
(N) fertilizer use efficiency up to 30%.
Table 3: Fertilizer use efficiency of various nutrients under fertigation
Nutrient
Fertilizer Use Efficiency
Soil application Drip Drip +
Fertigation
Nitrogen 30- 50 65 95
Phosphorous 20 30 45
Potassium 50 60 80
Timing of fertigation to coincide with periods of demand from the crop (growth curve
nutrition) is a common method of maximizing fertilizer efficiency in many high value crops with
complex phonology and nutrition requirements. However, Buller et al. 2002 reported that splitting
nitrogen applications evenly over the first four months of sugarcane crop development lead to
more efficient and productive use of nitrogen than the growth curve nutrition approach. In another
study conducted on sugarcane cultivation under drip-fertigation at PFDC Pantnagar, India showed
that sub-surface drip irrigation under paired row planting at 75 cm x 75 cm spacing gave the
highest cane yield in main (129.84 tonnes / ha) as well as ratoon (137.46 tonnes/ha). This
treatment was significantly superior by recording increase of 35.67 % in main and 40.15 % in
ratoon crop over surface irrigated sugarcane planted at 75 cm x 75 cm spacing (PFDC Pantnagar
annual report 2009). Patel and Rajput, 2004 reported that fertilizer saving of 40% could be
achieved with fertigation system over conventional practice in okra crop without affecting the yield.
They also reported that more than 16% increase in yield under fertigation (16.59 – 25.21%) over
broadcasting at the 100% level of recommended fertilizer application.
7. Chemigation System
System EU shall not be less than 85 percent where fertilizer or pesticides are applied
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