Genetic Variation of Growth Traits and Seed Production in a Patagonian Native Pasture in Semiarid Rangelands Under Different Environmental Settings

Abstract

Rangelands play a crucial socioeconomic and environmental role worldwide.In South America, desertification and overgrazing has led to their deterioration and decliningproductivity. Breeding programs that use native forage species of economic andecological importance, such as Festuca pallescens (St. Yves) Parodi, may provide locallyadapted germplasm that enhances productivity without threatening local biodiversity.These programs may even promote the conservation of native species. To this end, wecharacterized the phenotypic variation of nondestructive variables (growth and reproductivetraits) related to forage and seed production during spring and early summer (growthand reproductive periods). Plants from ten populations were grown under common gardenconditions in two environmental settings (sites) over two years. By early summerof the second year, most populations maintained a consistent relative performance withhigher values for basal diameter, height and synflorescence production at site 2. Thissuggests more favorable environmental conditions for the species and highlights theirpotential for enhancing both seed and forage production. The growth and reproductivetraits were probably largely influenced by micro-environmental cues (i.e., soil type andmoisture), showing predominantly plastic patterns. The populations displaying phenotypicplasticity and above-average values for both traits were selected for further evaluation inbreeding programs.