Tuber crop is some food crop which is converted into swollen organs due to accumulation of starch in the stem or root. Important tuber crops produced in Bangladesh include potato , sweet potato , kachu , metealu , cassava etc. These crops can also be used to make various industrial products like starch , alcohol and medicinal products. Tuber Crop: Sweet potato, locally known as potato, is an important vegetable and supplementary food crop in Bangladesh which is second only to paddy and wheat in terms of production and third in terms of cultivable land after paddy and wheat. The land under potato in Bangladesh and the annual production in the fiscal year 2005-06 was 6 lakh 44 thousand acres and 41 lakh 81 thousand metric tons respectively. Mainly two types of potatoes are produced in Bangladesh: local varieties (Lalshil , Lalpakari , Hagrai , Indukkani) and foreign high yielding varieties. These varieties are mainly cultivated in the north-western part of the country , occupying about 35% of the total land under potato cultivation.