Improving the identification, handling and storage of “difficult” seeds ...

- Low Constant temperature oven method, particularly used for oil crops. To attain the
required moisture content, samples are kept at 101 – 103 °C for 17 hours.
- High constant temperature oven method – This method is used to determine the moisture
content in cereal seeds, samples are kept at 130–133 °C for 4 hours for large seeded cereals
(like maize) and for 2 hrs for other cereals and also 1 hr for other species.
Storage containers
Seeds being kept in the long- and medium-term are sealed in laminated aluminum foil bags. Paper
bags are used for those seeds that are stored under short-term storage condition.
Viability monitoring (question 5.5)
The Institute performs viability monitoring on ex-situ collections. Monitoring is usually done every
7-10 years from the date stored. Different substrates are used for germination testing:
▪ Sand for large seeds (100 seeds per Petri dish with 2 replications)
▪ Filter paper for small and medium sized seeds (50 seeds per Petri dish with 4 replications)
Species that demonstrate low level of viability during initial tests
Sorghum sp.
Oryza sp.
As studies that focus on the effect of storage age on species under conservation are lacking, it is
difficult to generalize about species that show a significant increase or decrease in % germination or
no significant change.
Constraints (question 5.10) and possible solutions
▪ Drying room facility – the old drying room has been working for 30 yrs (1976-2006), the
equipments of the dry room are so old , the dehumidifier is not working properly, causing a
reduction in viability
▪ Lack of trained manpower to maintain gene bank facilities (high dependency on
experts/technicians from abroad)
▪ Lack of proper data base management
▪ Lack of duplicate gene bank
Possible solutions to the constraints
▪ Installation of new drying room facilities
▪ Build human capacity through training & strengthen facilities for study and data management.
▪ Establish a duplicate gene bank and other mini-gene banks elsewhere in the country.