Despite an increase in sales for the first quarter of the current financial year, lower than expected cotton yields and a hike in price of the raw material had a negative impact on profitability at garment manufacturer Gangotri Textiles Ltd.   Net sales jumped to Rs36.96 crore compared with Rs28.03 crore in the same period last year, and were offset by raw material costs which rose to Rs22.55 crore (Rs16.65 crore). Profit before depreciation, interest and tax fell to Rs4.40 crore (R 4.67 crore), and after tax dropped to Rs62 lakhs (Rs1.58 crore).