Bangladesh (low-land tropics with only one crop per year during the cool winter season) cultivates around 120.000 ha of potatoes. The yield is about 10 tonnes per hectare.
"indigenous" varieties with an average yield of 7.4 tonnes per hectare and 60% is cultivated with "modern" varieties from India and the Netherlands.
The Bangladesh Agricultural Development Cooperation (BADC) plays a major role in the seed industry of the country. The seed of the modern varieties distributed in the country is both from imports and from BADC locally produced seed. With the development of the seed programme BADC has been able to replace imported seed (3000 tonnes in 1979 and 100 tonnes in 1997) by locally produced seed stocks.
The seed volume produced by BADC meets 10% of the modern variety seed planted in the country. The remaining seed is from the non-formal private sector.
Seed of the "indigenous" varieties is mainly farmer's own seed.
Viruses are a major problem in seed production since virus degeneration is relatively high. Special measures are needed to reduce virus spreading.
Virus strategy Bangladesh
In Bangladesh degeneration due to viruses is relatively high. BADC applies general measures in order to reduce spreading of virus diseases as well as a number of specific measures.
Specific measures to reduce virus infection
In the BADC seed programme the following techniques are applied to reduce virus infections:
With the compact block system it is avoided that clean seed stocks are planted near infection sources.
- growing seed by contract growers in compact blocks
- early planting of the crops to escape virus infection
- use of high quality basic seed
- rouging and aphid control
Scattering of fields and plot size===Compact block for seed multiplication====
Clean seed multiplied near infection sources
BADC uses seed farms for the first multiplication of imported basic seed.
Until some years ago brown rot was not a serious problem since annually relative large quantities of healthy seed were introduced in the country and many of the potatoes were grown on land flooded during the monsoon. The problem became more serious when it became routine to multiply seed stock for more generations and occasionally potatoes were grown on land that is not regularly flooded. An example is the basic seed farm in Dibiganj.
Seed is stored for 8-9 months: "Modern" variety seed is stored in refrigerated stores. The "indigenous" variety seed can be stored using natural ventilation in houses and sheds, which makes these varieties attractive to subsistence farmers.
The indigenous varieties have been used for more than 100 years. They represent 40% of the potato acreage and are mainly grown by subsistence farmers. The seed stocks are infected by viruses, but by positive selection at farm level, improvements can be made.
Seedplot with positive selection