EVALUATION OF WALNUT (JUGLANS REGIA L.) BIOTYPES FROM NATURAL POPULATIONS OF MOLDOVAN POMOLOGICAL ZONES

Republic of Moldova is a country with ancient walnut culture tradition. During the lot of centuries there are intensively outspreaded by seed multiplication. Main selected and used for establish orchard biotypes was local bearing trees (also originated from seed) has good qualities and high productive potential. Actually it is indispensable to grow adequate varieties in concordance with the specific agro-ecological conditions and especially for modern market demands. Our studies were focused on evaluation of perspective local walnut biotypes, selected from different natural populations of local pomological zones (north, north-vest, central and south) comparatively to autochthonous and some introduced registered for multiplication in the Republic of Moldova varieties. The assessment enclosed walnut main descriptors, and sensory attributes including nut form, weight, structure (including index of shape form, total kernel weight, index of kernel/endocarp relation), kernel structure, color, flavor, texture, specific eating qualities, etc. The nut shape of the biotypes, selected as important ones was mainly rated oblate to ovate. Biotypes of north zone were recorded to have the whitest shell color and high index of kernel/endocarp relation: 45-59% of kernel were noticed at 13 biotypes. Most of the biotypes had a moderate kernel fill and shriveling score. The highest score of aroma, flavor and sweetness intensity was noted in central pomological zone (1Cmd, 2Cmd, 3Cmd, 17Cmd). In general bitterness, puckeriness and sweetness assessments greatly changing among local varieties and biotypes. Crispness rating of the ?iotypes was almost the same in all zones. Thus, on the basis of obtained data we suppose the existence of genetically important native trees (genotypes) all around the Moldovan studied areas. We are considering that there is necessary to conduct in-situ and on-farm inventories also for assessment and future utilization of the mentioned walnut gene fond.