Evaluation of morphological traits, dry matter yield and quality of Lolium perenne L. autochthonous populations from Serbia through multivariate analysis

Abstract

Due to specific climatic conditions, perennial ryegrass breeding in Serbia is focused on resistance or tolerance to abiotic stress factors, especially to drought and high temperatures. These traits should be associated with high dry matter yield and quality. Therefore, most frequently used initial material is autochthonous populations and ecotypes adapted to local agro-ecological conditions, but knowledge about their variability of important traits for breeding is missing. Pre-selection evaluation of ten populations of perennial ryegrass originating from Serbia is presented in this paper. Twenty five traits were investigated during the two-year period and processed using analysis of variance and multivariate statistical methods (cluster and principal components analysis). The goal was to determine diversity and genetic distances of investigated populations by phenotyping and to define traits considerably affecting the variability and discrimination of populations. On cluster diagram two groups of population are observed, but geographic origin of populations (lowland, hilly, mountainous habitat) was not influence to clustering of collection. Factor analysis has clarified that first seven principal components (PC) described almost 95%. The traits which show high correlation coefficients with first principal component were plant height in first cut, leaf length and width, DM of generative tillers, spike and spikelet length and 1000 seed weight, and with second principal component time of heading, terminal internode length, DM of vegetative tillers, spikelet number and FSU. It can be concluded that variability between populations was high and that differences of population were mainly affected by most important traits for breeding, such as components of dry matter production and some seed yield components.

Usled specifičnih klimatskih uslova, oplemenjivanje engleskog ljulja u Srbiji je fokusirano na toleranciju abiotičkih faktora stresa, posebno na sušu i visoke temperature. Stoga se kao početni materijal u oplemenjivanju najčešće upotrebljavaju autohtone populacije i ecotipovi prilagođeni lokalnim agro-ekološkim uslovima. Međutim saznanja o varijabilnosti najvažnijih osobina kod autohtonih populacija su vrlo ćesto oskudna. U ovom radu su predstavljena proučavanja varijabilnosti osobina deset populacija engleskog ljulja poreklom iz Srbija. Dvadeset pet osobina je ispitivano tokom dve godine, a podaci su obrađeni analizom varijanse i multivarijacionim statističkim metodama (PCA i klaster analiza). Cilj je bio da se utvrdi raznovrsnost i genetička udaljenosti ispitivanih populacija fenotajpingom i da se definišu osobine koje značajno utiču na varijabilnost i grupisanje populacija. Klaster analizom utvrđene su dve grupe populacija, ali geografsko poreklo populacija (ravničarska, brdska i planinska staništa) nije uticalo na pomenuto grupisanje. Faktorska analiza je pokazala da prvih sedam glavnih komponenti (PC) opisuje 95% varijabilnosti. Osobine koje pokazuju visok koeficijent korelacije sa prvom glavnom komponentom su visina biljaka u prvom otkosu, dužina i širina lista, suva materija generativnih izdanaka, dušina klasa i klasića i težina 1000 semena. Utvrđena je visoka varijabilnost između populacija koja uglavnom potiču od oplemenjivački najvažnijih osobine, kao što su komponente prinosa suve materije i neke komponente prinosa semena.