Description
White clover (Trifolium repens L.) is the main forage legume species in grazing pastures in central and southern Chile and many other temperate regions of the world. Its growth rate is limited by low temperature, therefore, the selection of cold stress resistant genotypes is an important step for breeding cultivar to improve the clover growth curve and extend the grazing season in early spring and autumn. The main objective of this experiment was to determine the relationship between phenotypic traits, measured by the high-throughput phenotyping procedures based on canopy reflectance at different wavelengths (spectral reflectance indices, SRIs), and dry matter production (DM). An association mapping population of 192 genotypes, selected for cold stress resistance from naturalized white clover germplasm collected in the Patagonia (Argentina and Chile) was used. These genotypes were clonally, propagated and established in three contrasting regional winter-cold conditions. The measurements were done in spaced plants and eleven SRIs were calculated. An alpha-lattice experimental design with 24 incomplete blocks and two replicates was used. The SRIs GM1 and 2, and Vg1, 2 and 3, showed the highest phenotypic (rf) and genetic (rg) correlation values with DM production (0.70 and 0.84, respectively), with high values of broad-sense heritability(H2) (average, 0.81). The technological impact of these results in a white clover breeding program would be the main conclusion. Six SRIs reached high genetic correlation coefficient (>0.8) with dry matter production, and broad-sense heritability (>0.7) values.
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Spectral Reflectance Indices Associated With Biomass Production of Cold Stress Resistant White Clover Genotypes Collected in Argentine and Chilean Patagonia
White clover (Trifolium repens L.) is the main forage legume species in grazing pastures in central and southern Chile and many other temperate regions of the world. Its growth rate is limited by low temperature, therefore, the selection of cold stress resistant genotypes is an important step for breeding cultivar to improve the clover growth curve and extend the grazing season in early spring and autumn. The main objective of this experiment was to determine the relationship between phenotypic traits, measured by the high-throughput phenotyping procedures based on canopy reflectance at different wavelengths (spectral reflectance indices, SRIs), and dry matter production (DM). An association mapping population of 192 genotypes, selected for cold stress resistance from naturalized white clover germplasm collected in the Patagonia (Argentina and Chile) was used. These genotypes were clonally, propagated and established in three contrasting regional winter-cold conditions. The measurements were done in spaced plants and eleven SRIs were calculated. An alpha-lattice experimental design with 24 incomplete blocks and two replicates was used. The SRIs GM1 and 2, and Vg1, 2 and 3, showed the highest phenotypic (rf) and genetic (rg) correlation values with DM production (0.70 and 0.84, respectively), with high values of broad-sense heritability(H2) (average, 0.81). The technological impact of these results in a white clover breeding program would be the main conclusion. Six SRIs reached high genetic correlation coefficient (>0.8) with dry matter production, and broad-sense heritability (>0.7) values.
