Calibration of Pesticides for Field Use

Calibration of Pesticides for Field Use

It is necessary to know the strength of the chemical available in the market for calibration of pesticides for field use. The following are some of the commonly used insecticides along with its strength and trade names.

           
The following formula may be used for the calibration of pesticides:
 ×  =
Where in
 = Concentration or percentage of the toxicant in trade product available in the market
 = Quantity of formulated insecticide required
 = Concentration or percentage of the actual toxicant in spray material needed
 = Quantity of the spray material needed

Problems:

1. A farmer wants to spray cotton with monocrotophos 0.06% against sucking pest complex. Calculate the quantity of insecticide required to spray 2 hectares of cotton using 600 liters of water/ha.
 ×  =
36 ×  = 0.06 (600 lit × 2)
 =
 =
 = 0.01 × 200
 = 2.00 liters/2 hectares
2. A cultivator has sprayed 1000 ml of Dimethoate 30 EC using 1000 liters of spray solution or 2 hectares of safflower for the control of safflower aphids. Calculate the concentration of the spray solution applied by the cultivator.
 ×  =
30 × 1000 ml =  × 1000 ml
30 × 1 lit =  × 1000 lit
 × 1000 = 30 × 1
 =
 = 0.03 %
3. Calculate the concentration of quinalphos 25 EC when it is applied at the rate of 150 g a. i. / ha. The spray solution used / ha is 500 liters.
25 g a. i.                                  100 ml trade product
150 g a. i.                                ?
=
=150 × 4
= 600 ml
 ×  =
25 × 600 ml =  × 500 lit
25 × 0.6 lit =  × 500 lit
 × 500 lit = 25 × 0.6 lit
500 × = 15
=
 = 3/100
 = 0.03%
4. Phorate 10 G is applied at the rate of 1 kg a. i. / ha. Calculate the quantity of Thimet required / 2 hectares.
10 g Phorate                                        in 100 g thimet
1000 g (1 kg) Phorate                         ?

=
= 10,000 g
=10 kg / ha × 2
= 20 kg / 2 hectares
5. Endosulfan 4 G is applied at the rate of 2 kg a. i. / ha. Calculate the quantity of Endosulfan 4 G required hectare.
4 g a. i.                                    100 g trade product
2000 g a. i. (2 kg a. i.)                         ?
=
= 500 × 100
= 50,000 g
= 50 kg