Trends in carrot production and breeding in Japan

Abstract

Carrot is one of the most important vegetables in Japan. In addition to large acreages of carrot root production (18,500 ha), extensive use of hybrid cultivars and high seed price make the Japanese market one of the biggest carrot seed markets (more than 3 billion JPY = 20 million Euros at wholesale level) in the world. Total root production reaches 544 kilotons and more than 85% are used for fresh purposes. There are three major cropping segments in Japan, “Summer sowing”, “Main season” and “Early sowing”. In the main carrot production area, cultivation is mechanized from to harvest. In some big production places, washing and packing are also getting highly mechanized. In all segments, the 'Kuroda' type and 'Chantenay' type hybrid cultivars are used. But leading cultivars vary depending on segments and region. Also breeding requirements are slightly different between the segments. In all segments, slightly conical shape with 16-18 cm root length and very uniform root shape with appropriate root size are preferred, in order to achieve high marketable yield. Recently, seed amount per hectare is decreasing (450,000 seeds ha-1) to minimize thinning costs. As the result, demands for seed quality and germination are also getting higher. Today, there are five major carrot seed suppliers in Japanese carrot market, and a few other seed companies are rising. Trends in carrot breeding at Japanese seed companies seem to be exploiting new hybrid cultivars with adaptability for mechanical harvest and with highly uniform root shape and size to give high income profit to growers. These trends seem obvious in the Summer sowing and “Early sowing” segments. Currently, some hybrid cultivars used in Japan are also taking significant market share in the hybrid carrot seed market in China that has potential to be the biggest carrot seed market in the world.