CGN melon collection
The history of the melon collection is analog to the CGN collections of tomato, pepper, eggplant and cucumber and described in the general page of the fruit vegetables. It was adopted in 2005, this more recently than the other fruit vegetables.
Composition
The melon collection is small. It only contains accessions which cannot be found in other collections; 17 accessions originate from the Netherlands. Part of the collection originates from the former IVT, and about 30 accessions were collected during an IPGRI collection mission in Pakistan in 1981. In 2017, a collecting expedition took place in Uzbekistan where 141 samples were collected. Currently, 79 accessions are available because regeneration is needed to meet CGN standards. The available collection comprises of 23 cultivars, 42 landraces, mostly from Pakistan and Egypt, and 14 accessions of unknown population type. Melon comes in many different types and can be sweet to sour.
Maintenance
To be incorporated in the collection, accessions need to have a minimum seed viability of 80% for cultivated material and 60% for accessions of wild species. Regeneration is carried out when seed viability is to low or when the remaining seed quantity has dropped below 12.5 g. Regeneration/multiplication takes place in insect-free glasshouses on a substrate system where the stems are grown along ropes. For melon, which is a cross-fertilising species, ten plants are used. When samples are heterogeneous, fourteen plants are used. Breeding companies, organised in Plantum NL, assist in the regeneration of melon. Accessions which are difficult to regenerate are placed in isolation cages with bumble bees for pollination. During the growing season, plants are monitored by the Dutch Plant Health Service for seed borne diseases in order to prevent seed contamination.
Characterisation
Characterisation of fruit vegetables takes place during regeneration. Almost all accessions have been morphologically described. Melon is characterised by minimum descriptors developed by the ECPGR Working Group. The minimum descriptor lists consist of about ten descriptors and can be found at the ECPGR Cucurbits webpage. All characterisation data are made available online and in downloadable files.
The collections are well photo-documented, many pictures of (un)ripe fruits, plants, and flowers are available. When necessary, new pictures will be taken during regeneration and added to the CGN website.
Evaluation
About 18 accessions of the collection were genotyped by sequencing in 2014 as part of the “100 Melon Genomes Project”.