History and prospects of zoning and registration of walnut (<i>Juglans regia</i> L.) varieties

Abstract

Purpose. To study the history of zoning and registration of walnut varieties in Ukraine.

Results. The walnut has occurred in the zoned assortment of 1937 with recommendations for growing in the favourable conditions of the sou­theast of Ukraine. Due to the absence of approbated walnut varieties it was not discussed about varietal culture. For the first time the walnut variety of national breeding has been zoned only in 1954. In Soviet period walnut varieties were recommended for cultivation in 7 western and southern regions of Ukraine. In the end of ХХ century 4 varieties of H. M. Vysotskyi Ukrainian Research Institution of Forestry and Sylvicultural Reclamation breeding and 9 varieties of Prydnistrovska Experimental Station of Horticulture bree­ding have been zoned. To boost up the registration of new walnut varieties it have started to carry out according to the applicant’s data, supposing after-registration tests under conditions of various horticultural regions. At this time 10 varieties of the Nikitskyi Botanical Garden bree­ding and a number of varieties of both the Moldavian (7) and the French (6) breeding have been registered in the State Regis­ter of plant varieties. Mass reproduction of new walnut varieties and use them in industrial plantations in the regions without preliminarily tests, have led to a frost-killing of some plantations. Process of registration of new walnut varieties of both national and foreign selection is procee­ding and their list will be increase.

Conclusions. 52 walnut varieties were zoned or registered in the Ukrainian State Register, including 34 varieties of national selection within 1954–2018. The State Register of plant varieties of Ukraine (on the date 2018) comprises 33 walnut varieties, including 16 varieties of national breeding and 17 varieties of foreign breeding. 19 varieties were excluded from the Register because they were not maintained by their applicants. Geographical dilating for walnut industrial cultivation demands corresponding after-registration testing for reception of authentic results concerning their behavior in the conditions which are distinct from where they have been originated.