The Effect of Exposure of Mulberry to Acid Rain on the Defects Cocoon of Bombyxmori L

Air pollution may be indicated by the higher acid rain. Air pollution caused by the burning of fossil fuels increase emissions of SOx,NOx, and CO2 which can ultimately lead to acid rain. Exposure of acid rain may affect the cultivation of mulberry and the quality of silkworm cocoon. The aim of this research was to determine the effect of mulberry plants that have been exposed to acid rain to the percentage of cocoon defects and type of defects in C-301 and BS-09 races of Bombyxmori L. Acid rain that to applied on mulberry plant for 5 weeks was a modification of acid rain that occurred in Sidoarjo East Java, Indonesia. A total of 720 individuals of newly hatched silkworm were used in early research. Larvae fed by mulberry leaves that had been treated with artificial rain water in different levels of pH, i.e. pH's of 7.0 (well water as control), 6.2 (normal rain), and 4.6 (acid rain). Cocoon defects and type of cocoon defect were observed. Data were analyzed using multivariate ANOVA. The results showed that the treatments had no significant effect (P >0.05) on defective cocoon percentage. Treatment of pH 7.0, 6.2, 4.6 had defective cocoons of 21.34%, 12.94%, 11.2%, respectively in race C-301 and 18.49%, 15%, 15.26%, respectively in race BS-09. Meanwhile, cocoon defect types in race C-301 and BS-09 were outer defects consisting of printed, outside stained, malformed, very small, double cocoons, and inner defect consist of thin-end and inside stained cocoons. As a whole, acid rain treatments to defective cocoon of Bombyx mori L. in C-301 and BS-09 races showed no significant effect to defective cocoons.