Calibrations at 20
C are recommended every 6 months. Workstations and display units should be calibrated as pairs. More
information about the theoretical basis and the use of a
“Rotronic” water activity sensor for measuring seed moisture
can be found in [29, 31].
12. Software for “Rotronic” workstations units (e.g., HW4
“Rotronic” monitoring system, www.rotronic.com) can be
logged by connecting the display unit to a “Roline” software
loaded on a PC, tablet, or smartphone. This allows controlled
logging and data manipulation via Excel. Although these units
can be powered by battery, routinely mains connection is
preferred.
13. The choice of container depends on the volume of the sample
and should be as full as possible, ensuring air gaps are kept to a
minimum. Multiple containers per sample are preferable,
allowing for samples to be removed for testing without the
need to remove the whole collection. Any quarantine material
must be foil bagged, due to the risk of leakage from vials. Seeds
over 10 mm in diameter should not be backed up to cryostorage due to the risk of the seed coat cracking and therefore
becoming damaged during freezing/thawing procedures. Any
seeds with sharp or spiny edges, which may damage foil bags,
should be prepacked in a protective packet, such as card or
paper. A suitable database for assigning and storing bank locations is recommended.
14. Ideally samples stored in the cryo-dewar should not be exposed
to room temperature to avoid temperature fluctuations. These
fluctuations can increase the temperature of the sample and
could produce negative effects in the samples, either by ice
crystallization (in the case of samples stored at high water
contents such as embryonic axes) or by lipid melting and
recrystallization cycles (in intermediate seeds, orthodox oily
seeds and fern spores). However, as moving racks, canisters,
boxes, or canes from the cryo-dewar may be unavoidable when
collections are inserted or removed from LN, some recommendations must be followed to avoid damage to other collections
already stored in the cryo-dewar. These recommendations follow those suggested in the Best Practices for Repositories of
the International Society for Biological and Environmental
Repositories (ISBER) [40]:
(a) If a new box or cane is introduced in the cryo-dewar, the
rack or the canister containing other boxes or canes
should be kept just above the cryo-dewar only for the
brief time needed to insert the box in an empty space. In
samples going into large cryo-dewars, two people may be
needed, one holding the rack and the other inserting or
676
Daniel Ballesteros et al.
C are recommended every 6 months. Workstations and display units should be calibrated as pairs. More
information about the theoretical basis and the use of a
“Rotronic” water activity sensor for measuring seed moisture
can be found in [29, 31].
12. Software for “Rotronic” workstations units (e.g., HW4
“Rotronic” monitoring system, www.rotronic.com) can be
logged by connecting the display unit to a “Roline” software
loaded on a PC, tablet, or smartphone. This allows controlled
logging and data manipulation via Excel. Although these units
can be powered by battery, routinely mains connection is
preferred.
13. The choice of container depends on the volume of the sample
and should be as full as possible, ensuring air gaps are kept to a
minimum. Multiple containers per sample are preferable,
allowing for samples to be removed for testing without the
need to remove the whole collection. Any quarantine material
must be foil bagged, due to the risk of leakage from vials. Seeds
over 10 mm in diameter should not be backed up to cryostorage due to the risk of the seed coat cracking and therefore
becoming damaged during freezing/thawing procedures. Any
seeds with sharp or spiny edges, which may damage foil bags,
should be prepacked in a protective packet, such as card or
paper. A suitable database for assigning and storing bank locations is recommended.
14. Ideally samples stored in the cryo-dewar should not be exposed
to room temperature to avoid temperature fluctuations. These
fluctuations can increase the temperature of the sample and
could produce negative effects in the samples, either by ice
crystallization (in the case of samples stored at high water
contents such as embryonic axes) or by lipid melting and
recrystallization cycles (in intermediate seeds, orthodox oily
seeds and fern spores). However, as moving racks, canisters,
boxes, or canes from the cryo-dewar may be unavoidable when
collections are inserted or removed from LN, some recommendations must be followed to avoid damage to other collections
already stored in the cryo-dewar. These recommendations follow those suggested in the Best Practices for Repositories of
the International Society for Biological and Environmental
Repositories (ISBER) [40]:
(a) If a new box or cane is introduced in the cryo-dewar, the
rack or the canister containing other boxes or canes
should be kept just above the cryo-dewar only for the
brief time needed to insert the box in an empty space. In
samples going into large cryo-dewars, two people may be
needed, one holding the rack and the other inserting or
676
Daniel Ballesteros et al.