Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
treatment irrigated at 50-70kPa soil moisture tension and 75% of normal fertilizer doses (I 3 F 1 ) by
281.31 % higher as compared to the control treatment. The water use efficiency was increased
higher in the treatment by 248.05 % as compared to the control treatment in WT NVPH. The water
productivity of treatment irrigated at 50-70 kPa soil moisture tension and normal fertilizer doses
(I 3 F 2 ) was observed to be decreased by -72.43 under DS NVPH and -71.45 % under WT NVPH in
treatment irrigated at 50-70kPa soil moisture tension and 75% of normal fertilizer doses (I 3 F 1 ) as
compared to control treatment (Table3).
Table 3: Effect of tensiometer based irrigation and fertigation on capsicum yield (kg/m 2 ),
water use efficiency and water productivity in DS NVPH and WT NVPH
Treatment DS NVPH WT NVPH
Yield
(kg/m 2 )
WUE
(kg/m 3 )
Water
productivity
(liter/kg)
Yield
(kg/m 2 )
WUE
(kg/m 3 )
Water
productivity
(liter/kg)
I 1 F 1 12.00 48.18 20.76 12.35 40.73 24.60
I 1 F 2 12.34 49.55 20.33 13.81 45.53 22.01
I 2 F 1 10.92 62.74 17.07 11.67 81.37 12.94
I 2 F 2 12.28 70.55 14.40 13.49 70.66 14.20
I 3 F 1 13.14 100.59 10.15 13.04 90.91 11.00
I 3 F 2 12.54 96.00 10.47 11.94 83.19 12.08
C 8.52 26.38 37.98 9.56 26.12 38.53
CD
(P=0.05)
NS 20.47 4.56 NS 17.51 4.12
I 1 : Drip irrigation at 20-30 kPa soil moisture tension; I 2 : Drip irrigation at 30-50 kPa soil moisture
tension; I 3 : Drip irrigation at 50-70 kPa soil moisture tension; F 1 : 75% of recommended fertilizer
doses; F 2 : 100% of recommended fertilizer doses
6. Automated Watering
Watering a large number of plants in a well-stocked greenhouse can be a major task,
especially if it is to be done by hand. However, there are alternative approaches available,
including seep hoses, drip irrigation, misters and sprinkler systems, which make the job much
easier. Many of these systems can be automated to varying degrees, using modern timers or
controllers, which range from the cheap and simple to the very sophisticated – with a price tag to
match! Water timers, for instance, fit between the irrigation hose and the tap and can be set to
allow watering to take place at specific times of the day and for a given period, allowing you to
water at night to avoid evaporation, for example, without having to be there yourself. These
relatively simple devices are also invaluable if you are out all day or when you go away, keeping
the soil nicely moist in your absence. More complex water controllers can take the automation
even further, measuring soil moisture and watering accordingly to keep the growing conditions at
their optimum.
7. Water Quality Management for Green House Irrigation
A dependable irrigation water supply is a vital component of any greenhouse growing
operation. In the past, the quality of the water source was not a cultural issue considered by
growers. The water source may contain essential nutrients such as iron or nitrate in high enough
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