Field Experiment and Yield per Plot
As showed in Table 1, results of F-test on plant weight (g), curd diameter (cm), Leaf width (cm) per plant
and yield per plot (g) indicated that there were significant differences among treatments; however leaf length was
not significant difference. The mean curd yields of treatments with doses 3 ml of S. curtisii and 25 ml/L of
S. tuberosa are the highest yield among all treatments, 9792 and 8960 g/plot (12 m2) respectively. The lowest
mean populations of P. xylostella were found at treatments of 25 ml/L of S. tuberosa and 3 ml/L of S. curtisii at the
1.80 and 1.67 larvae per plant respectively.