The tomato collection maintained by AVRDC – The World Vegetable Center: composition, germplasm dissemination and use in breeding

With about 82,400 accessions, the section Lycopersicon in the genus Solanum is well represented in ex situ collections around the globe. The single largest collection (approximately 10% of total global resources) is held by AVRDC NDASH The World Vegetable Center in Taiwan, followed by genebanks in the United States, the Philippines, Germany, the Russian Federation, and Japan. AVRDCRSQUOs tomato collection is composed of cultivated tomato (6,142 S. lycopersicum accessions NDASH mostly traditional cultivars and landraces, and 125 S. lycopersicum var. cerasiforme accessions), crop wild relatives (812 accessions), and genetic stocks (595 accessions) composed of interspecific hybrids, introgressed lines, and recombinant inbred lines. A total of 585 accessions still lack proper species identification. After pepper (Capsicum spp.), tomato is AVRDCRSQUOs second most widely distributed vegetable crop. Wild relatives of tomato have been crucial in the improvement of pest and disease resistance and abiotic stress tolerance of cultivated tomato through classical breeding. Virtually all significant resistance genes to tomato diseases were sourced from wild relatives. Research work at AVRDC has focused on the introduction of resistance genes into cultivated tomato against late blight, bacterial wilt and leaf curl (caused by begomoviruses) and the development of heat-tolerant lines. Since 1978, 180 tomato cultivars have been released in 45 countries worldwide based on AVRDC-developed open-pollinated, heat-tolerant and multiple disease-resistant germplasm. In addition, nine commercial tomato lines have been released by seed companies in India using AVRDC breeding lines as parent material in the development of hybrids. This success was possible due to the genetic building blocks conserved in AVRDCRSQUOs diverse tomato collection.