Progress 04/01/02 to 03/30/08
Outputs
OUTPUTS: At the beginning of this project we had identified a total of 34 new clones capable of producing up to 135% more stem biomass than the current standard commercial clone. We perfected a "mini-cutting" technique to scale up these selections for public use through the Iowa DNR Nursery. By 2007, we had an annual production of 5900 dormant cuttings by this method and made another 4000 cuttings available from stump sprouts and one-year-old nursery stock. An eight-year-old study of cottonwood leaf beetle (Chrysomela scripta) impact was completed showing biomass dry weight production could be increased up to 45% when the trees were protected from severe beetle outbreaks over the first three years. In a seven-year-old Melampsora leaf rust impact study, susceptible clones had only 80% of the height growth and 54% of the dry stem weight production of their resistant sibling clones. The best clones from both studies were added to the scale-up of nursery production. Breeding work was
continued to produce 100 new F1 and F2 crosses with about 10,000 progeny placed in field tests. Seven transgenic lines of aspen developed for resistance to crown gall were found to grow at similar or significantly slower rates than the parental clone and to have more of a tendency for the development of frost cracks in their stems. A study of white and bur oak seed storage and germination was completed. Seed size does have a positive effect on most early growth variables. Thermal analysis of acorn starch shows promise of indicating metabolic alterations during storage and desiccation. Results have been communicated to the scientific community through the publications listed. We have provided outreach in terms of technical expertise and starter materials to the Iowa DNR Nursery system, one private enterprise tree nursery and one consulting forester and several of his clients. Some data collection and analysis remains to be completed on the leaf rust and F1/F2 breeding studies and
manuscripts will be prepared for publication on those two studies and the transgenic aspens.
PARTICIPANTS: Richard B. Hall, the PI, is the Wallace Endowed Professor of Forestry. The endowment provided much of the current expense money for this project. Five graduate students received all or part of their thesis research training working on aspects of the project, Valasia Iakovoglou (oaks), Stephen Ruigu (poplars) Jerome Thomas (aspens), and Ron and Jill Zalesny (poplars and phytoremediation). The Iowa Department of Natural Resources State Forest Nursery was a close collaborator on all the clonal scale-up work. There was frequent contact and some collaboration the forest industry companies GreenWood Resources, Jeld-Wen, and Nippon Paper Company.
TARGET AUDIENCES: The project was aimed at developing new techniques and clones for use by the tree nursery trade and, ultimately, to provide better biomass production resources for Midwestern landowners.
Impacts
The new selections from this program will raise productivity levels to at least 8 dry tons/acre/yr of wood to support energy or fiberboard production; up from the 4.5 ton level of currently available planting stock. Some of these clones should also have valuable uses in agroforestry and phytoremediaition plantings. Field tests of those uses have begun. The nursery scale-up of these improved clones should result in the production of about 40,000 trees in 2008 and 160,000 improved trees by 2009. If the market for biomass planting stock warrants it, we can more than double the rate of increase using the mini-cutting technique we have tested. The cottonwood leaf beetle and Melampsora leaf rust impact studies should greatly improve plantation management strategies and establish the economic impacts of chemical pest control and selection of pest resistant clones. Several of the F2 families should prove valuable in molecular marker studies.
Publications
- Iakovoglou, V., M.K. Misra, R.B. Hall and A.D. Knapp. 2007. The effect of seed size and parent tree on seed variables and seedling growth of Quercus spp. Seed Science and Technology, 35:776-782
- Hall, R.B. 2006. Genetically engineered trees: Controversy and uncertainty. Timber Talk (Newsletter of the Iowa Woodland Owners Association). Feb, 2006 p. 4.
- Coyle, D.R., E.R. Hart, J.D. McMillin, L.C. Rule, and R.B. Hall. 2008. Effects of repeated cottonwood leaf beetle defoliation on Populus growth and economic potential over a full harvest rotation. Forest Ecology and Management. Accepted.
|
Progress 01/01/06 to 12/31/06
Outputs
Scale-up of improved clones for distribution by the Iowa DNR nursery entered its second year. A total of 1650 rooted cuttings were produced. From the tops of those trees, 5900 cuttings have been prepared for the 2007 nursery crop. A "mini-cutting" technique was used to grow an additional 2650 trees in the 2006 nursery and prepare another 4000 for the 2007 nursery. Harvesting and data collection from an eight-year-old study of cottonwood leafbeetle (Chrysomela scripta) impact was completed and a manuscript is in preparation. For the two best clones in the study, biomass dry weight production increased 36 to 45% when the trees were protected from severe beetle outbreaks over the first three years. In a partial harvest of a seven-year-old Melampsora leaf rust impact study, susceptible clones had only 80% of the height growth and 54% of the dry stem weight production of their resistant sibling clones.
Impacts
At least one new commercial clone recommendation will result from the leaf rust study. The nursery scale-up should result in the production of 40,000 trees in 2008 and 160,000 improved trees by 2009. If the market for biomass planting stock warrants it, we can more than double the rate of increase using the mini-cutting technique. When fully analyzed the results of the two impact studies should greatly improve plantation management strategies and establish the economic impacts of leafbeetle control and selection of pest resistant clones.
Publications
- Zalesny, R.S. Jr., E.O. Bauer, R.B. Hall, J.A. Zalesny, J. Kunzman, C.J. Rog, and D.E. Riemenschneider. 2005. Clonal variation in survival and growth of hybrid poplar and willow in an in situ trial on soils heavily contaminated with petroleum hydrocarbons. International Journal of Phytoremediation 7:177-197.
|
Progress 01/01/05 to 12/31/05
Outputs
Eleven cottonwood clones selected for improved growth and pest resistance were planted at the Iowa DNR nursery to begin scale-up for public use. Eight new selections were made in a hybrid aspen progeny test; seven of the selections have been scaled up and planted in a clonal test. Over 100 genotypes were planted for each of three sibling inbred families that segregate for a leaf rust resistance gene. Initial data were collected on different types of resistance that are being expressed and on on leaf pigmentation variation. Harvesting work began on an eight-year-old study of the impact of the cottonwood leafbettle on the growth of four cottonwood clones.
Impacts
The new cottonwood clones grown at the Iowa DNR nursery will more than double the diversity of clones available and increase productivity by up to 45%. New insights on genetic interactions in leaf rust resistance should be gained if our field work can be combined with on-going molecular studies.
Publications
- Zalesny, R.S., Jr., R.B. Hall, and. D.E. Riemenschneider 2005. Soil temperature and precipitation affect the rooting ability of dormant hardwood cuttings of Populus. Silvae Genetica 52:47-58.
- Zalesny, R.S., Jr., R.B. Hall, and. D.E. Riemenschneider . 2005. Early rooting of dormant hardwood cuttings of "Populus": analysis of quantitative genetics and genotype x environment interactions . Can. J. For. Res. 35:918-929.
|
Progress 01/01/04 to 12/31/04
Outputs
The genetics component of this project remained on a maintenance status. We selected and used 8 parents to make 9 different F1 crosses. Over 5300 rooted cuttings of improved clones were produced in the nursery. A study of white and bur oak seed storage and germination was completed. Seed size does have a positive effect on most early growth variables. Thermal analysis of acorn starch shows promise of indicating metabolic alterations during storage and desiccation.
Impacts
We have several of our new clones in field tests in the Midwest and the Pacific Northwest. We did a research summary on the Crandon clone as part of an industrial feasibility study for developing up to 5000 acres of plantations. Initial results indicate several clones show substantial promise for commercial use. The Iowa DNR State Nursery will begin producing some of these clones in 2005.
Publications
- Kosola, K.R., D.I. Dickmann, R.B. Hall, and B.A.A. Workmaster . 2004. Cottonwood growth rate and fine root condensed tannin concentration. Tree Physiology 24:1063-1068.
- Bae, H.H., H.D. Kang and R.B. Hall. 2004. Competition responses of Populus alba clone 'Bolleana' to red:far-red light. Korean J. Plant Res. 7(1):78-87.
|
Progress 01/01/03 to 12/31/03
Outputs
Less than $5,000 of temporary funding was available for the genetics component of this project in 2003, so the project was on a maintenance status. We selected and used 21 parents to make 24 different F1 crosses. We planted 2446 seedlings in field and nursery progeny tests. Limited scale-up of improved clones was done in the nursery for distribution to two commercial trials in 2004. The third and final year of data collection for the Loess Hills buffer study has been completed. The study makes use of one of the superior cottonwood clones developed from the genetics work. Preliminary analysis of these data indicates a significant increase in tree biomass when compared to switchgrass, smooth brome, and alfalfa with woody biomass now exceeding 8000 g/m2 compared to 2000 g/m2 for the next highest species, smooth brome. The amount of phosphorus tied up in vegetation exhibits similar increases. The rhizosphere solution chemistry research needed to support the modeling work
that is part of this project has revealed definite phosphorus concentration gradients in the soil with increasing distance from a root. Gradients were also detected along the root based on how long the root had been in contact with the soil. Graduate students = 1.
Impacts
We are in the process of providing samples of our best clones to be grown in support of approximately 30,000 acres of biomass energy and fiber plantations in Iowa and surrounding states and the Pacific Northwest. We will continue working with the Iowa DNR State Nursery and commercial nurseries to get these improved clones into sufficient production to supply further planting demands. Results of the buffer study demonstrate the impact that woody species like cottonwood can have on the retention of phosphorus on site. Modeling efforts will provide a means to quantify the potential impacts of various types of buffer configurations on the retention of phosphorus.
Publications
- Coyle, D. R., J. D. McMillin, R. B. Hall and E. R. Hart. 2003. Effects of cottonwood leaf beetle (Coleoptera: Chrysomelidae) larval defoliation, clone, and season on Populus phagostimulants. Environ. Entomol. 32(3):452-462.
- Zalesny, R. S., Jr. 2003. Genetic and Environmental Effects on Rooting Ability of Dormant Unrooted Hybrid Poplar Cuttings. Ph.D. Dissertation, Iowa State University. 189 p.
|
Progress 01/01/02 to 12/31/02
Outputs
A long-term project funded by USDOE was completed. As a result of this project, a total of 34 new clones capable of producing up to 135% more stem biomass than current standard commercial clone have been made available for use in the region. We selected and used 118 parents to make 500 different F1 crosses and began F2 breeding in 2002. We produced 47,600 seedlings for field progeny tests. From these tests, 615 clones were taken into further evaluations and 168 of those were recommended for long-term regional tests. Significant strides were made in understanding the genetic control of Melampsora leaf rust and the population structure of the causal fungus. We have found 40% reductions in two-year stem volume as a result of Melampsora impact. Similarly, we determined that the cottonwood leaf beetle, Chrysomela scripta, can cause losses of up to 71% in stem volume when outbreaks are not controlled. In 2002, we made another 56 crosses and produced another 6500 progeny for
field testing. Seven transgenic lines of aspen developed for resistance to crown gall were found to grow at similar or significantly slower rates than the parental clone and to have more of a tendency for the development of frost cracks in their stems. In a greenhouse study using the NM-6 cross maximal growth rate was found to be 0.12 g g-1 per day at a whole plant ratio of 100N:11P:37K. The Barber-Cushman model was run using soil supply and root growth data from the greenhouse study. Nitrogen, P, and K uptake were simulated for a 105-day period in response to a slow release 17-6-12 fertilizer at rates equivalent to 0, 75, or 150 kg ha-1 of N. Model predictions of uptake improved as the amount of fertilizer added increased. Uptake estimates at the 150 level were 96, 120, and 98% of observed N, P, and K uptake. The model predicted that N supply was not adequate to support sustained plant uptake throughout the growth period. Plant uptake and soil supply observations confirmed that N
uptake occurred primarily in the first half of the growth period and that soil N supply was quickly depleted. Graduate students = 2.
Impacts
The new selections from this program will raise productivity levels to at least 7 dry tons/acre/yr of wood to support energy or fiberboard production; up from the 4.5 ton level of currently available planting stock. Based on a factory trial of our material in 2002, a fiberboard company with a mill in Dubuque is considering planting approximately 2500 acres of new plantations with our improved planting stock. Results suggest that the Barber-Cushman model can be used as a way to evaluate potential nutrient addition regimes. This will allow nutrient additions to be better matched with plant needs and existing soil supply and should reduce the loss of nutrients by leaching. Reduction in nutrient loss will have favorable consequences both economically and environmentally.
Publications
- Adam ML, JM Kelly, WR Graves and PM Dixon. 2003. Net nitrate uptake by Acer rubrum is a function of root zone temperature. J. Plant Nutrition 26:203-222.
- Coyle DR, JD McMillin, RB Hall and ER Hart. 2002. Cottonwood leaf beetle (Coleoptera: Chrysomelidae)defoliation impact on Populus growth and above-ground volume in a short rotation woody crop plantation. Agriculture and Forest Entomology 4:293-300.
- Coyle DR, JD McMillin, RB Hall and ER Hart. 2002. Deployment of tree resistance to insects in short-rotation Populus plantations. pp. 189-215 In: (MR Wagner, KM Clancy, F Lieutier and TD Paine, eds.) Mechanisms and Deployment of Resistance in Trees to Insects. Kluwer Academic Publishers. Dordrecht. 332 p.
- Easley, Thomas R. 2002. Growth, propagation, and ethical considerations with using aspens genetically engineered for crown gall resistance. M.S. thesis, Iowa State University 60 p.
|
|