Simple measures to preserve seed potato quality in the period between farm delivery and planting were discussed at the Sutton Bridge Storage Event recently, coinciding with the issue of a new Seed Storage Technical Note.
Hosting a workshop session with Sutton Bridge colleague Dr Glyn Harper, Potato Councils Communications Officer Sophie Lock described that a recent seed survey of 170 businesses revealed a clear knowledge gap in growers understanding of what to do with seed post-delivery.
Jumbo bags are not good storage vessels, she noted. And whilst it is best to decant seed immediately after delivery, it is acceptable to leave seed in bags for a very few days after delivery. Facilitate ventilation by stacking the bags with plenty of space between them and raise them off the floor onto pallets to limit temperature variances in the bag,” she said.
The importance of inspecting seed on delivery was also highlighted. Potato Councils Glyn Harper noted that the delivery should match the order documents and be of the expected quality. Each bag should carry an official label with details matching the variety, grade and size ordered. There should also be an official seal which should be intact on delivery, he said.
Glyn went on to advise that storage of up to two weeks prior to planting should ideally see the seed decanted into boxes or stores, which must be CIPC free. The biggest concern with leaving seed in jumbo bags is poor airflow which allows condensation to build-up in the middle of the bags, and lead to the development of disease which can develop up to six times faster in bags.
Glyn pointed to a Sutton Bridge experiment comparing best practice short-term storage where seed was decanted into boxes, with a worst practice scenario where seed remained in the bags for a six week period, and were subjected to fluctuating temperatures.
Even though the experiment was conducted in the winter period, the sprouting that occurred in the bagged seed was up to 2.5mm compared to minimal levels in the decanted stocks. There was also a marked difference in the levels of silver scurf.
For seed that has to be stored for more than two weeks, Potato Council advises that once decanted, the seed should be cured and ideally placed in a seed store and cooled down to approximately 3 degC. Where this is unavailable, temporary ventilation will be necessary. This involves construction of a temporary plenum chamber from either boarding or canvas for use with a portable fan. The fan should help maintain an even temperature, but this is a method that demands regular inspection of seed condition and temperature, and modifying airflow as required.
For more information, download the new PCL Technical Note TN03 Best practice for seed handling and storage. Visit: www.potato.org.uk/seedhandling