Concentration  (ppm)

Concentration    difference

No. of alive larvae

No. of dead    larvae

Mean
death

 Mean death     x
Concentration difference

  0 (control)

0 (check)

200

400

600

800

1000

0

0

200

200

200

200

200

 

20

20

16

13

10

06

0

 

0

0

4

7

10

14

20

 

0

0

2

5.5

8.5

12

17

 

0

0

400

1100

1700

2400

3400

                                                                                                      Total              9,000

The LC50 value of the leaf extract of Annona squamosa for 48 h has been determined according to the arithmetic method of Karber (1931). The calculation was done as following:


LC50 = 1000 – 450
LC50 = 550 ppm
Table 4: The LC50 value of ethanol extract of Annona squamosa leaves for 48 h.