Description

Abstract: Study was planned out in 3×3+1 factorial experiment with check in randomized complete block design with 4 replications. Two factors were studied namely factor A as a number of spray applications and factor B as a kind of insecticides. The spray application consisted of A1 as 3 sprays made at R3, R4 and R5, A2 as 2 sprays at R4 and R5 and A3 as l spray at R5. The insecticides used were B1 as 0.1 % methamidophos, B2 as 0.1 % monocrotophos and B3 as 0.1 % omethoate. Peanut variety, Tainan 9, was planted on June 9, 1990 in the plot size of 3×5 m width, the spacing of 50×20 cm at Rayong Field crops Research Centre. The spray applications were firshly made on 21 August, secondly on 4 September and thridly on 20 September 1990. Data collected on a number of damaged pods, unfilled pods and yield in kg. per rai were made on l November 1990 from 4 middle rows. Finally, 100 seed weight and shelling percentage were also find out. The results revealed that significant difference among the insecticides used were observed. Methamidophos 0.1 % gave less number of damaged pods while omethoate 0.1 % resulted in less number of unfilled pods as compared to the others. However, all the insecticides used were not affected on 100 seed weight and shelling percentage at all. In case of spray applications, significant difference at p=0.5 were observed on shelling percentage. Two spray application made at R4 and R5 seem to be superior to the others by 68.73 %. Moreover, if the spray was made with 0.1 % omethoate the shelling percentage will be as high as 72.73 %. However, both spray applications and insecticides used in this experiment did not cause any difference in yields obtained.