Abstract
Juvenile growth and bud set phenology were analyzed to study the biological basis of heterosis (hybrid vigor) in interspecific hybrids of Populus tremuloides Michx. (T) and P. tremula L. (Ta). Growth, measured as seedling volume index, was significantly higher for each of the two reciprocal interspecific crosses, T x Ta and Ta x T, than for the T x T intraspecific cross. Broad-sense heritabilities were 2-6 times larger than narrow-sense heritabilities for growth and shoot components in the T x T intraspecific cross, suggesting an important role for dominance or overdominance in aspen growth. Previous genetic analyses have indicated that hybrid vigor may be the result of overdominance at several key loci each with an allele inherited from each of parental species. Internode length and leaf number contributed substantially to the heterosis of stem volume, but their effects on heterosis differed between the T x Ta and Ta x T hybrids. In T x Ta seedlings, heterosis of stem volume was attributed to a high diameter growth rate, whereas in Ta x T seedlings heterosis of stem volume was probably the result of delayed bud set resulting in a longer duration of height growth. In addition to internode number and length and leaf number, other morphological or physiological components might affect heterosis, for example, extended leaf retention.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 29-36 |
| Number of pages | 8 |
| Journal | Tree Physiology |
| Volume | 18 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 1998 |
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All Science Journal Classification (ASJC) codes
- Physiology
- Plant Science
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Developmental factors responsible for heterosis in aspen hybrids (Populus tremuloides x P. tremula). / Li, Bailian; Howe, Glenn T.; Wu, Rongling.
In: Tree Physiology, Vol. 18, No. 1, 01.1998, p. 29-36.Research output: Contribution to journal › Article
TY - JOUR
T1 - Developmental factors responsible for heterosis in aspen hybrids (Populus tremuloides x P. tremula)
AU - Li, Bailian
AU - Howe, Glenn T.
AU - Wu, Rongling
PY - 1998/1
Y1 - 1998/1
N2 - Juvenile growth and bud set phenology were analyzed to study the biological basis of heterosis (hybrid vigor) in interspecific hybrids of Populus tremuloides Michx. (T) and P. tremula L. (Ta). Growth, measured as seedling volume index, was significantly higher for each of the two reciprocal interspecific crosses, T x Ta and Ta x T, than for the T x T intraspecific cross. Broad-sense heritabilities were 2-6 times larger than narrow-sense heritabilities for growth and shoot components in the T x T intraspecific cross, suggesting an important role for dominance or overdominance in aspen growth. Previous genetic analyses have indicated that hybrid vigor may be the result of overdominance at several key loci each with an allele inherited from each of parental species. Internode length and leaf number contributed substantially to the heterosis of stem volume, but their effects on heterosis differed between the T x Ta and Ta x T hybrids. In T x Ta seedlings, heterosis of stem volume was attributed to a high diameter growth rate, whereas in Ta x T seedlings heterosis of stem volume was probably the result of delayed bud set resulting in a longer duration of height growth. In addition to internode number and length and leaf number, other morphological or physiological components might affect heterosis, for example, extended leaf retention.
AB - Juvenile growth and bud set phenology were analyzed to study the biological basis of heterosis (hybrid vigor) in interspecific hybrids of Populus tremuloides Michx. (T) and P. tremula L. (Ta). Growth, measured as seedling volume index, was significantly higher for each of the two reciprocal interspecific crosses, T x Ta and Ta x T, than for the T x T intraspecific cross. Broad-sense heritabilities were 2-6 times larger than narrow-sense heritabilities for growth and shoot components in the T x T intraspecific cross, suggesting an important role for dominance or overdominance in aspen growth. Previous genetic analyses have indicated that hybrid vigor may be the result of overdominance at several key loci each with an allele inherited from each of parental species. Internode length and leaf number contributed substantially to the heterosis of stem volume, but their effects on heterosis differed between the T x Ta and Ta x T hybrids. In T x Ta seedlings, heterosis of stem volume was attributed to a high diameter growth rate, whereas in Ta x T seedlings heterosis of stem volume was probably the result of delayed bud set resulting in a longer duration of height growth. In addition to internode number and length and leaf number, other morphological or physiological components might affect heterosis, for example, extended leaf retention.
UR - http://www.scopus.com/inward/record.url?scp=0031914503&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031914503&partnerID=8YFLogxK
U2 - 10.1093/treephys/18.1.29
DO - 10.1093/treephys/18.1.29
M3 - Article
AN - SCOPUS:0031914503
VL - 18
SP - 29
EP - 36
JO - Tree Physiology
JF - Tree Physiology
SN - 0829-318X
IS - 1
ER -