Accumulation of selenium in sugarcane (Sachharum officinarum Linn.) in seleniferous areas of Punjab, India.
A survey was conducted during 1986-88 to assess the level and pattern of accumulation of selenium in sugarcane plants in seleniferous areas of Punjab (India). Total and water-extractable (available) selenium ranged from 0.55 to 2.58 (mean 1.43 ± 0.67) mg kg(-1) and from 0.02 to 0.05 (mean 0.033 ± 0.007) mg kg(-1), respectively, in seleniferous areas. Corresponding values from non-seleniferous areas were 0.23-0.55 (mean 0.36 ± 0.08) mg kg(-1) and 0.015-0.025 (mean 0.020 ± 0.003) mg kg(-1), respectively. Sugarcane tops from seleniferous areas accumulated high levels of selenium ranging from 7.9 to 67.5 mg kg(-1). These selenium levels were 6-14 times higher than those from non-seleniferous areas. During the early stages of growth (June), the selenium content was highest but decreased during the months of July and August and then did not change up to maturity. In the seleniferous areas sugarcane tops and canes at maturity contained 5.7-9.5 and 1.8-2.1 mg Se kg(-1), respectively. However, the tops and canes of plants growing near the permanent boundary (bundh) contained 9.5-18.8 and 2.1-2.4 mg Se kg(-1), respectively.In a field experiment on sugarcane, application of gypsum up to 1 ton ha(-1) resulted in a significant reduction of selenium content in sugarcane tops as well as in the cane. Selenium content in sugarcane tops at maturity was reduced from 15.16 to 5.08 mg kg(-1) by applying gypsum of 1 ton ha(-1).