A comparative study on the quality parameters of mulberry (Morus alba L.) leaves irrigated with sewage and borewell water.

摘要

Mulberry leaf samples (V₁ variety) were collected from ten villages in and around Kengeri and Bidadi area in Bangalore district, Karnataka where the farmers are using sewage and bore well water as source for irrigation. All the leaf samples collected were analysed for different biochemical parameters following the standard test methods. The results showed a significant increase in reducing sugars, Phenolic compounds, two micronutrients (Mn & Cu) in the samples collected from sewage irrigated gardens over bore well irrigated gardens. Though higher concentration of carbohydrate, total chlorophyll, carotenoid, nitrogen and potassium were estimated in leaf samples of sewage water irrigated gardens over bore well irrigation these were not significant. This indicated the presence of high nutrient content in sewage water. However leaf samples from sewage irrigated gardens showed a significantly higher concentration of heavy metals such as Cu, Cd, Pb and Ni over bore well irrigation. The correlation analysis between different biochemical parameters and heavy metal contents in leaf samples showed that reducing sugar has a positive correlation at 1% with Cu, Cd and Pb content. Where as the protein content showed a significantly negative correlation with Cu, Zn, Cd and Pb. Many of these metals are toxic to the plants when present at a level more than the threshold limit. Although the leaf quality was improved with sewage water irrigation over bore well water irrigation, its adverse effects on the silkworm and soil health need to be studied in depth.