The study on the clone selection and assessment for the seed orchard of Pinus massoniana

Based on the investigation on the yield and characteristics,and the determination of wood specific gravity of 132 clone seeds from Pinus massoniana seed orchard,and the investigation on the growth characteristics of 8-year-old open pollination progenies,the elite clones were selected by the integrated assessment,20% of which were selected.The results showed it was feasible to build improved seed orchards by the clone re-selection from the Pinus massoniana seed orchard.10.6% improved gain in volume and 4.6% gain in wood specific gravity could be obtained from the 8-year-old progenies.The selection effect was evident that 37.5% gain in single individual seed yield could be obtained,which achieved the purpose of improving seed orchard yield and increasing the genetic gain.