Raffaele Testolin

University of Udine, Italy

 Kiwifruit, as many fruit crops, suffers several constraints, like the impossibility of selfing to produce inbred parent lines, the long juvenile period of seedlings to reach the reproductive stage, the large space occupied by seedlings during the evaluation and selection. To these drawbacks we must add the dioecy that impedes crossing female by female genotypes, and forces breeders to carry out the progeny test to evaluate the genetic value of male parents. For all these reasons, kiwifruit breeding is still in its infancy all around the world, in spite of its industry having a spectacular development during the last 50 years, reaching 0.2 % of the world’s fruit basket. The University of Udine of Italy has been committed since 1980’s to carry out controlled crosses aiming to study the genetic control of traits and to create new varieties that could meet the evolution of the market demand. The report of the experiences of the Udine’s group from the introduction of genetic material from overseas, to the first studies on the heritability of traits, to the progeny test on male parents used in the controlled crosses, to the molecular approach to the identification of trait-controlling loci through markers and maps, to the genome sequencing and gene annotation, to the most updated genome-based selection has been chosen by the author to figure out an ideal track to the modern kiwifruit breeding. The genetics of traits of interest like fruit size, flesh colours, sugar content and quality, allergens and others is briefly discussed. The report includes also the perspectives offered by the interspecific hybridization to produce novel types of fruit and the genome editing approach to overcome the dioecy and to produce hermaphroditic varieties. The presentation will stress the difficulties to introduce genetic material from China, the kiwifruit home land of the genus Actinidia due to the Rio Convention of June 1992 (https://www.cbd.int/rio/) and the Nagoya protocol of 2010 (https://www.cbd.int/abs), entered in force in 2014 and the risk that threatens this crop in the western world due to the narrow genetic diversity exported from China. The presentation continues with the discussion of the breeding programs of the main kiwifruit-growing countries like China, Japan and New Zealand. Finally, the author describes the original approach of ‘breeding on demand’ where the growers’ organization figures out its objectives and funds the breeding project, while the public Institutions develop the program. As a result, growers are the owners of the new varieties and pay royalties to the Institution that feeds the basic research.