Variation of Pollination Rate on Eucalyptus grandis and E. tereticornis

The most widely used clones were all breed by artificial hybrids steps in China, therefore it is important to research on pollination rate. Three individual trees of E. grandis and E. tereticornis were selected as female while the pollen of hybrid clone DH32-29, E. grandis, E. pellita, E. tereticornis and E. urophylla were collected as male. The results indicated that E. grandis family 4 always had higher pollination rate with different male pollen than other E. grandis families. Family 116 had higher pollination rate with DH32-29 and E. urophylla than family 41 while family 41 had higher pollination rate with E. grandis and E. tereticornis than family 116. Though different families had different pollination rate, the studied E. grandis families all had higher pollination rate (above 75%) with different male pollen. E. tereticornis family 243-1 always had higher pollination rate (nearly 100%) with different male pollen than other E. tereticornis families while E. tereticornis family 238-2 always had lower pollination rate (nearly 60%) with different male pollen than other E. tereticornis families. All the male pollen had similar pollination rate with family 238-1 and 243-1. E. grandis pollen had higher pollination rate with family 238-2 than other male pollens.