Abstract
Sixteen green asparagus cultivars from 6 countries were planted in a greenhouse in Hangzhou, China (120.2°E, 30.3°N) in 2016. The annual cultivation system, consisting of one spring harvest using the conventional method, along with two summer and autumn harvests using the mother-stem method, was applied. The seasonal and annual total yields were determined in the first and second years of harvest, i.e., in 2017 and 2018. In every harvest season, spears were cut at the length of 37 cm and their quality and total yield were evaluated. ‘Pacific Challenger 1’, ‘Sunlim’, ‘Pacific Challenger 2’, ‘Pacific Endeavor’ and ‘H2-4’ were the top 5 yielders during the first two years of harvest. The average spear weight of ‘Italo’, ‘Sunlim’ and ‘Early California’ was over 20 g in all harvest seasons. In the second harvest year, the yield of ‘Pacific Challenger 1’, ‘Pacific Challenger 2’ and ‘Grande’ produced a relatively higher total yield than other cultivars in spring. The yield of ‘Pacific Challenger 2’ was the highest in summer, while ‘Italo’, ‘Pacific Challenger 1’, and ‘Pacific Challenger 2’ showed higher yield in autumn. Among three harvest seasons, the yield of all cultivars in autumn did not reach the expected level, which may have been caused by the typhoons, Capricorn and Winbia, in August 2018, as well as the deficiency of necessary fertilization. Overall, ‘Pacific Challenger 2’ seemed to be a good yielder in all harvest seasons during the second year of harvest and looked to be a promising cultivar to be cultivated in the greenhouse conditions in Hangzhou, China.