Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Pollen contamination and its influence on the second generation Eucalyptus pellita seed orchard.

Abstract

Objective: Pollen contamination in forest tree seed orchards can affect their gene purity and genetic structure. This study aimed lo understand pollen contamination patterns and its influence on important traits in high- genemlion Eucalyptm pellita seed orchard. an exotic species, to provide a scientific basis for its germplasm conservation and long-lerm improvement. Method: Using 167 E. pellita families fmm four seed orchards as genetic material. with leaf morphology as discriminating traits, this study analyzed 1.5-2.0 years [rial data for pollen contamination rate and its distribution us well as its eHects on plant growih, health and flowering phenology. Result: Eucalyptus pellila from all four sources exhibited pollen contamination. Contamination rates were significantly different (P < 0.05) between sources. ranging from 18.75% to 35.50%. Family-level contamination rale was 92.81%. The contamination rates among families (within source) were highlysignificantly different (P < 0.01). Pollen contamination highly significantly affected (P < 0.01) leaf morphological traits, mainly leading m narrower leaves with a lighter color and thinner wax layer. However, it did not significantly affect leaf altitude. The effects of pollen contaminalion on [he leaves were mostly significant among the four sources. Pollen contamination did not significantly affect tree volume growth and flowering phenology bul signifi- cantly decreased tree. health index by 4.74% (P < 0.01). Conclusion: Pollen contamination rate in the second-genera- tion E. pellita was at a medium level. The results can be applied in modifying the methods of genetic conservation of E. pellim and preventing genetic contamination.