Genetic variation and breeding of Silver fir in Romania

Inglés. This paper presents the results of the researche carried on in four Silver fir provenance trials and in one half – sib family trial, at the age of 25. The tested material includes 60 Silver fir provenances, 33 Romanian and 27 foreign, from 8 European countries: France (3), Germany (3), Austria (4), Italy (4), Poland (1), Czech Republic (3), Slovakia (4), Bulgaria (5). The experimental trials were settled on the following forest districts: Sacele (2), Domnesti, Moinesti and Strambu Baiut. The researche focused on assessment of genetic variation for the most important traits, the magnitude of variation and genetic variation pattern, the selection of best provenances and families with regard to productivity traits and adaptability. the investigated traits have been the total height, volume / tree, diameter at 1,30m, branches characters, stem straightness and survival rate. Correlations with the main geographical gradients, narrow – sense heritability and expected genetic gain have also been estimated. In all comparative trials the variance analysis has showed a great interpopulational genetic variability for the majority of studied traits. Genetic variation is both clinal and ecotype and depends on the examined character. The most significant correlations have been found with longitude and latitude of the origin. Generally, good performances for growth traits and great stability have been obtained for Romanian provenances and for foreign provenance as follows: 44 – Lepilat (France) and 23 – Rakitovo (Bulgaria). Provenances from Italy and Austria have achived the lowest growth performances. Interpopulational genetic variability is much higher than the intrapopulational one. At - families level significant differences have been obtained only for growth characters, number of branches in verticil and survival rate. Heritability coefficent shows a high genetic control for these traits and the expected genetic gain suggests that selection at families level and individuals level would be rewarding.

Rumano; Moldavo; moldavo. În aceastã lucrare sunt prezentate cercetãrile desfãºurate în patru culturi comparative cu provenienþe de brad ºi o culturã de descendenþe materne, la vârsta de 25 de ani. Materialul testat cuprinde 60 de provenienþe de brad; 33 româneºti ºi 27 strãine; din 8 þãri europene: Franþa (3), Germania (3), Austria (4), Italia (4), Polonia (1), Republica Cehã (3), Slovacia (4), Bulgaria (5). Suprafeþele experimentale sunt amplasate în urmãtoarele ocoale silvice: Sãcele (2), Domneºti (1), Moineºti (1) ºi Strâmbu Bãiuþ (1). Cercetãrile au urmãrit evaluarea variaþiei genetice a principalelor caractere, magnitudinea variaþiei ºi tipul de control genetic, selecþia celor mai bune provenienþe ºi familii sub aspectul producþiei de masã lemnoasã ºi adaptabilitãþii. Caracterele studiate au fost urmãtoarele: înãlþimea totalã, diametrul la 1,30m, volumul mediu/arbore, caracterele ramurilor, forma trunchiului ºi supravieþuirea. De asemenea, au fost estimate corelaþiile cu gradienþii geografici de origine, eritabilitatea în sens restrâns ºi câºtigul genetic aºteptat. În toate culturile comparative, analiza varianþei evidenþiazã o variabilitate geneticã interpopulaþionalã mare pentru majoritatea caracterelor studiate. Variaþia geneticã este atât clinalã cât ºi ecotipicã ºi depinde de caracterul studiat. Cele mai multe corelaþii asigurate statistic au fost obþinute cu longitudinea ºi latitudinea de origine. În general, performanþe bune de creºtere ºi stabilitate ridicatã au obþinut provenienþele din România ºi provenienþele strãine: 44 _ Lepilat (Franþa) ºi 23 _ Rakitovo (Bulgaria). Cele mai slabe rezultate au obþinut provenienþele din Italia ºi Austria. Variabilitatea geneticã interpopulaþionalã este mult mai mare decât cea intrapopulaþionalã. Diferenþe semnificative la nivel de familie au fost obþinute doar pentru caracterele de creºtere, numãrul de ramuri în verticil ºi supravieþuire. Coeficientul de eritabilitate evidenþiazã un control genetic ridicat pentru aceste caractere iar câºtigul genetic aºteptat sugereazã cã selecþia la nivel de familie ºi individ va fi profitabilã.