Variation in Phenological Development of Winter Barley

Abstract

Phenology of small grains as a complex trait that matches plant development with growing conditions is an important factor that influences plant adaptation to a particular environment and final yield of the plant. Scales of growth based on plant phenology and scales of development based on apical morphology are very precise, but relationships between them are not always clear. Some morphogenetic features of cereal growth can be predicted on the basis of leaf appearance, which means that shoot apex development is coordinated with leaf appearance and total number of leaves formed. The objective of this research was to study the relationship between apical development and plant phenology and the variability in phenological development of diverse winter barley cultivars under field conditions. Twelve barley cultivars differing in origin, pedigree, and agronomic traits were used in this study conducted during six growing seasons in the location of Novi Sad (45°20′N, 15°51′E, altitude 86 m) under rainfed conditions. Phyllochron approach was used as a method for determination of initial/final stages of apex development. The duration of the phases was converted to cumulated growing degree days (GDD). Spikelet initiation started at 2.5 Haun stage and finished at 7.1 Haun stage. Preanthesis phases (single ridge – SR, double ridge – DR, spikelet development – SD, heading – H, anthesis – A) and grain filling period (GFP) were under significant effect of genetic (G), environmental (E), and interaction factors (G × E). Of the total variation in the DR phase, 55.7% was due to G × Y, 22.1% due to E, and 12.3% due to G. Spikelet development was mainly under control of G and E, 42% and 44%, respectively. Heritability was 0.57 and 0.95 for DR and SD, respectively. Across cultivars and environments, of the total growing period, 138 GDD belonged to sowing-first leaf period, 161 to SR, 326 to DR, 541 to SD, 254 to flag leaf-H, 142 to H-A, and 732 to GF. Although variability was found in the duration of the preanthesis phases and GF, especially in spikelet and flower development, positive genotypic correlations were found to exist between most of the phases.