Genetic variation and selection of 10-year-old Eucalyptus camaldulensis based on wind damage index and wood properties

Abstract

Typhoons are becoming frequent and intense with ongoing climate change, threatening ecological security and healthy forest development in coastal areas. Eucalyptus of a predominant introduced species in southern China, faces significant growth challenges because of typhoon. Therefore, it is vital to investigate the variation of related traits and select superior breeding materials for genetic improvement. Variance, genetic parameter, and correlation analyses were carried out on wind damage indices and eight wood properties in 88 families from 11 provenances of 10-year-old Eucalyptus camaldulensis. The selection index equation was used for evaluating multiple traits and selecting superior provenances and family lines as future breeding material. The results show that all traits were highly significantly different at provenance and family levels, with the wind damage index having the highest coefficient of genetic variation. The heritability of each trait ranged from 0.48 to 0.87, with the wind damage index, lignin and hemicellulose contents, and microfibril angle having the highest heritabilities. The wind damage index had a positive genetic correlation with wood density, a negative correlation with lignin content, a negative phenotypic correlation and a negative genetic correlation with microfibril angle. Wind damage index and genetic progress in the selection of eight wood traits varied from 7.2% to 614.8%. Three provenances and 12 superior families were selected. The genetic gains of the wind damage index were 10.2% and 33.9% for provenances and families, and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China.