Breeding of yellow-fleshed kiwifruit cultivar ‘Jinxi'

Abstract: 'Jinxi’is a yellow-fleshed kiwifruit cultivar with excellent fruit quality, its seedling is derived from a cross between‘Jintao’ (a yellow-fleshed cultivar of Actinidia chinensis) and‘Jinxiong No.1’ (a pollenizer strain of A.chinensis) in 2002 at the experimental field, and initially selected in 2007 for frui weight, fruit shape and superior taste.Throughout regional adaptability test at three sites and productive trial planting from 2008 to 2014, it was finally selected and named‘Jinxi’.In 2018, ‘Jinxi’has passed the examination and approved by crop variety approval committee of Zhejiang province.The fruit are cylindrical and moderate to large in size.It weighs 88.5 grams in average.The stylar end is flat or slightly concave, the fruit skin present yellow green to dark brown.The fruit flesh is golden-yellow and fine juicy Core appears yellowish white, its proportion in fruit flesh is small.The fruit has a fine texture, flavor is very sweet with aromatic taste, and mild with tangy aftertaste, smooth texture.The content of soluble solids, dry matters, total sugars, total acids and vitamin C is 15.0%-21.7%, 18.7%-23.5%, 12.2%-13.5%1.0%-1.2%and 1 416 mg·kg-1fresh weight, respectively.Timely harvesting is needed.When the conten of soluble solids in fruit reach over 7.5%, the harvest begin.The fruits have good storage quality:storage life 1-2 months at ambient temperature and more than 4 months at cool store.The shelf life of softening fruit at room temperature could be more than 15 days and 1-2 months under cool-stored condition.The fruit development period of‘Jinxi’is about 150 days.It begins to bloom in late April and its fruit matures in early October in Hangzhou area.The chromosome of‘Jinxi’is tetraploid, with moderate to strong vigor, the percentage of bud germination and shoot forming are 72.7%and 100%, respectively.Flowers occur at nodes 1-8 of the fruiting shoots, and there are often 5 to 8 inflorescences on these nodes, predominantly singly or inflorescences of 3 flowers.The fruit set rate is above 95%, and there is no physiologica fruit drop.‘Jinxi’is less susceptible to bacterial canker of kiwifruit (Psa) and has better performance under Psa condition.This cultivar is put into production early, with high and stable yield.Grafted plants of this cultivar start fruiting at the second year, and the output is above 1 000 kg per 666.7 m2at the fourth year after grafting.Spacing in the rows and spacing between rows could be 3 m×4 m or 4 m×4 m, using the pergola and T-bar system, with a single trunk and two permanent leaders.‘Jinxiong No.1’or‘Moshan male No.4’is recommended as pollenizer, the ratio of male to female could be 5-8:1.The inheritance character of‘Jinxi’is stable, with the characteristics of large fruit, good yield, good quality and less susceptible to bacterial canker.Areas suitable for cultivation include Zhejiang and similar regions.