Progress 10/01/05 to 09/30/11
Outputs
OUTPUTS: During the summer of 2011, experimental lines in maturity groups III-V were tested at six breeding nurseries located throughout Kansas. We also established a Soybean Sudden Death Syndrome/Soybean Cyst Nematode (SCN) site at one northeast Kansas location in the Kansas River Valley. The drought location established in central Kansas, in 2010, was expanded in 2011 and we are cooperating with the Univ. of Missouri, Univ. of Arkansas, Univ. of Nebraska, Univ. of Georgia and the USDA-ARS at NC-State to screen for drought resistance. We initiated a project in 2011 to produce a model for predicting yield in our soybean-breeding project using remote sensing. Throughout seed-fill we used a Spectroradiometer to obtain canopy readings of the plots. These reading are now being used to construct yield models. We completed the second year of field evaluations examining genotype response to heat and drought stress by measuring: pollen viability, antioxidants in the leaves, chlorophyll fluorescence, canopy temperature and grain yield in dryland and irrigated conditions. This study revealed physiological differences in genotypes that have occurred with the genetic improvement of soybean. Canopy temperature exhibited the strongest relationship with seed yield. In our work to study the inheritance and to map Dectes stem borer resistance gene(s) in PI 165673, we tested two F2 populations in the field from crosses between PI165673 with the susceptible accessions KS5004N and K07-1544 for stem borer resistance. Twenty days after infestation, the numbers of oviposition punctures (OvP) and larvae (Lv) were counted on each plant from the top five fully developed petioles to estimate the OvP/Lv resistance ratio. Segregation for resistance in the KS5004N/PI165673 indicated that resistance is controlled by one or two epistatic genes inherited as recessive traits. Segregation for resistance in the K07-1544/PI165673 indicated that resistance is controlled by two epistatic genes inherited as recessive traits. QTL mapping of resistance is in progress using parental polymorphic SSR markers. Approximately two hundred Soybean Performance Test entries were evaluated in replicated trials for their reaction to two representative Kansas SCN populations. Results are published annually at http://www.agronomy.k-state.edu/extension/DesktopDefault.aspxtabid=9 4. Seventy percent of entries were resistant or moderately resistant to an HG Type 7 population but only ten percent were resistant or moderately resistant to an HG Type 1.2.3.5.6.7 population. Female indices were positively correlated with sudden death syndrome (SDS) ratings across entries. Surveys of SCN prevalence and of HG Types in Kansas also were continued in 2011. Nearly five hundred samples from seventy-three counties have been collected and processed to date. Ten percent of samples collected across the state tested positive for SCN, but prevalence in Cherokee and Doniphan Counties exceeded 50%, with populations in infested fields averaging 2,000 and 150 eggs/100 cm3 soil, respectively. PARTICIPANTS: PI's: Schapaugh, breeder; Todd, nematologist; Trick, plant transformationist; Reese, entomologist; Smith, entomologist. Technicians: Dille, Oakley, Essig, Kusel Graduate Students: Keep, selection techniques, Christenson, remote sensing. Collaborators: Kimball, agronomist; Prasad, physiologist, Little, pathologist. TARGET AUDIENCES: Farmers, commodity groups, agricultural businesses, crop consultants. PROJECT MODIFICATIONS: None
Impacts
Germplasm with improved traits, unique combinations of traits, or new transgenic traits will have the following potential applications. 1) Our material can provide the foundation for the next cycle of genetic gain by serving as parents to develop new populations and new lines. 2) Our non-GMO material can be licensed and released directly as varieties for commercial production. 3) Our non-GMO material can be modified to possess appropriate GMO traits, such as herbicide resistance, and then released as varieties for commercial production. 4) Our transgenic material may enable us to demonstrate to the soybean industry the feasibility of technology that will ultimately provide solutions to problems facing soybean production and soybean utilization. Our management work, focusing on a number of pathogens will enable us to improve recommendations for appropriate management strategies. For example, our SCN work will improve our ability to accurately predict how a KSU-released or other commercial variety will perform across diverse Kansas SCN populations. This knowledge also will inform future decisions about which sources of resistance should be emphasized in the breeding program.
Publications
- Lee, J., Welti, R., Schapaugh, W.T., and Trick, H.N. 2011. Phospholipid and triacylglycerol profiles modified by PLD suppression in soybean seed. Plant Biotechnology Journal 9: 359-372.
- T. Niide, R. A. Higgins, R. J. Whitworth, W. T. Schapaugh, C. M. Smith and L. L. Buschman. 2012. Antibiosis Resistance in Soybean Plant Introductions to Dectes texanus. J. Econ. Ent. (accepted).
- Pierson, L. M., T. M. Heng-Moss, T. E. Hunt, and J. C. Reese. 2010. Physiological responses of resistant and susceptible soybean genotypes to soybean aphid (Aphis glycines Matsumura) feeding. Arthropod-Plant Interactions. 5: 49-58.
- M. Djanaguiraman, P. V. V. Prasad, D. L. Boyle and W. T. Schapaugh. 2011. High-Temperature Stress and Soybean Leaves: Leaf Anatomy and Photosynthesis. Crop Sci. 51: 2125-2131.
- N.R. Keep, W.T. Schapaugh Jr., P.V.V. Prasad, and J.E. Boyer Jr. 2011. Characterization of Physiological Parameters In Soybean with Genetic Improvement In Seed Yield. ASA Abstract.
- Marchi, L. S., T. J. Prochaska, T. Heng-Moss, T. E. Hunt, and J. C. Reese. 2011. Resistance characterization of the genotype KS 4202 to Aphis glycines Matsumura (Hemiptera: Aphididae). Entomol. Soc. Amer. National Meetings. Reno, NV. November 13-16, 2011. Poster.
- Prochaska, T. J., L. S. Marchi, T. Heng-Moss, T. e. Hunt, J. Reese, N. Palmer, Y. Xia, J.-J. Riethoven, and P. Twigg. 2011. Molecular insights into the tolerance response of KS4202 to the soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae). Entomol. Soc. Amer. National Meetings. Reno, NV. November 13-16, 2011. Poster.
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: During the summer of 2010, experimental lines in maturity groups III-V were tested at six breeding nurseries located throughout Kansas. Also, we established Soybean Sudden Death Syndrome (SDS)/Soybean Cyst Nematode (SCN) sites at two northeast Kansas locations. Advanced Roundup Ready material was entered in the Kansas Soybean Performance Tests to complement national trials. Over 100 new soybean populations were created in 2010. The purpose of many of the populations was to incorporate new genetic diversity into our program that might ultimately lead to the development of high-yielding varieties. We began converting three high yielding elite conventional lines into RR1 varieties. We completed the evaluation of over 3000 experimental K-lines and another 200 experimental lines from other states in replicated yield trials. Productivity and precision of the 2010 season was above average. Two new soybean lines, KS4610sp and KS4910sp, were released to producers for the first time in 2010. KS4610sp is an F4 single plant selection from the cross A01-611037 x KS4702sp. KS4610sp has white flowers, gray pubescence, tan pods at maturity, determinate growth habit, and seeds with yellow hila. KS4610sp is a mid group IV maturity variety. KS4910sp is an F4 single plant selection from the cross A01-611037 x KS4702sp. KS4910sp has white flowers, gray pubescence, tan pods at maturity, determinate growth habit, and seeds with yellow hila. KS4910sp is a late group IV maturity variety. In our work to study the inheritance and to map Dectes stem borer resistance gene(s), we sent populations to be advanced in the 2010/11 winter nursery that will produce progeny for evaluation. Greenhouse evaluations of approximately 3000 experimental varieties were completed this year to select for Soybean Cyst Nematode resistance. We completed the first year of field evaluations examining genotype response to heat and drought stress: pollen viability (germination and reactive oxygen species), antioxidants in the leaf tissue, chlorophyll fluorescence, canopy temperature and grain yield in dryland and irrigated conditions. PARTICIPANTS: PI's: Schapaugh, breeder; Todd, nematologist; Trick, plant transformationist; Reese, entomologist; Smith, entomologist. Technicians: Dille, Oakley, Essig, Erickson, Kusel Graduate Students: Meng, aphid resistance; Rzodkiewicz, nematology; Brzostowski, pathology. Collaborators: Kimball, agronomist; Maddux, agronomist; Prasad, physiologist, Little, pathologist. TARGET AUDIENCES: Farmers, commodity groups, agricultural businesses, crop consultants. PROJECT MODIFICATIONS: None
Impacts
Germplasm with improved traits, unique combinations of traits, or new transgenic traits will have the following potential applications. 1) Our material can provide the foundation for the next cycle of genetic gain by serving as parents to develop new populations and new lines. 2) Our non-GMO material can be licensed and released directly as varieties for commercial production. 3) Our non-GMO material can be modified to possess appropriate GMO traits, such as herbicide resistance, and then released as varieties for commercial production. Our most recent glyphosate-resistant variety (KS5507NRR), developed in this manner, was produced on several thousand acres in 2008. 4) Our transgenic material may enable us to demonstrate to the soybean industry the feasibility of technology that will ultimately provide solutions to problems facing soybean production and soybean utilization. Our management work, focusing on a number of pathogens will enable us to improve recommendations for appropriate management strategies. For example, our SCN work will improve our ability to accurately predict how a KSU-released or other commercial variety will perform across diverse Kansas SCN populations. This knowledge also will inform future decisions about which sources of resistance should be emphasized in the breeding program.
Publications
- Jiarui Li, Tom R. Oakley, Timothy C. Todd, William T. Schapaugh, and Harold N. Trick. 2010. Expression RNA interference of three nematode reproduction or fitness genes in soybean suppressed soybean cyst nematode fecundity. 12th IAPB World Congress/2010 In Vitro Biology Joint Meetings, June 6-10, St. Louis, MO.
- Chandran, P., J.C. Reese, D. Wang, W.T. Schapaugh, and L.R. Campbell. 2010. Feeding behavior comparison of soybean aphid (Hemiptera : Aphididae)biotypes on different soybean entries. Entomol. Soc. Amer. Ann. Mtg.
- Meng. J., Reese, J., Smith, C.M., and Schapaugh, W. 2010. QTL Mapping of Soybean Aphid Resistance In Soybean Genotype K1621. ASA Abstract.
- Brzostowski, L., Schapaugh, W., Little, C., Todd, T. 2010. Effect of F. Virguliforme and H. Glycines On Soybean. ASA Abstract.
- Rzodkiewicz, P., Todd, T., Little, C., and Schapaugh, W. 2010. Characterization of Soybean Cyst Nematode Diversity in Kansas. ASA Abstract.
- Maduraimuthu, D.,Prasad, P.V.V., Boyle, D., Schapaugh, W. 2010. Effects of Heat Stress During Flowering On Physiological and Ultra-Structural Changes in Soybean Leaves and Pollen Grains. ASA Abstract.
- Brzostowski, L.F., 2010. Effect of Fusarium virguliforme and Heterodera glycines on soybean. MS Thesis, KSU.
- Rzodkiewicz, P. A. 2010. Characterization of soybean cyst nematode diversity in Kansas. MS Thesis, KSU.
- Meng, J. 2010. Genetic analysis of soybean aphid resistance gene in soybean K1621. Ph.D. Dissertation, KSU.
- Helms, T.C., Scott, R.A., Schapaugh, W.T., Goos, R.J., Franzen, D.W. and Schlegel, A.J. 2010. Soybean iron-deficiency chlorosis tolerance and yield decrease on calcareous soils. Agron. J. 102: 492-498.
- Lee, J., Welti, R., Schapaugh, W.T., and Trick, H.N. 2010. Phospholipid and triacylglycerol profiles modified by PLD suppression in soybean seed. Plant Biotechnology Journal (online) 1-14 doi: 10.1111/j.1467-7652.2010.00562.x (KAES no. 10-294-J).
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: During the summer of 2009, experimental lines in maturity groups III-V were tested at six breeding nurseries located throughout Kansas. Also, we established Soybean Sudden Death Syndrome (SDS)/Soybean Cyst Nematode (SCN) sites at three northeast Kansas locations. Advanced Roundup Ready material was entered in the Kansas Soybean Performance Tests to complement national trials. Using composite interval mapping of a soybean aphid (SBA) resistance gene using SSR markers has revealed one quantitative trait locus (QTL) controlling the antibiotic resistance. This QTL explained 54% of the phenotypic variation in aphid number. A separate mapping population containing 106 F2:4 families derived from the cross of K1621 and Dowling was used to validate this QTL. Single marker analysis confirmed SSR markers closely linked to the putative QTL. In 2008 and 2009, studies were conducted to determine the effect genotype, F. virguliforme populations, and H. glycines populations have on seed yield. In 2008, four genotypes with different levels of resistance to SDS and SCN were planted at three locations where both pathogens were present. In 2009, six genotypes were planted at five locations. F. virguliforme and H. glycines soil populations were quantified three times during the growing season (planting, midseason, harvest), and SDS foliar ratings were taken after symptoms appeared. Populations of F. virguliforme and SCN were variable across and within locations. SCN populations were not high in any location. Genotype performance in seed yield varied with environment. As disease pressure increased, an increase was observed in the relative performance of resistant varieties compared to susceptible varieties. Information from these studies will improve decisions regarding cultivar selection to minimize losses to SDS and SCN. In 2007 through 2009, soil samples were collected from SCN-infested soybean fields across the state to characterize the diversity of soybean cyst nematode populations in Kansas. Approximately sixty samples from locations in central and eastern Kansas have been collected. The Heterodera glycines (HG) type test is being performed on each SCN population collected to characterize the virulence of each population, with nearly fifty type tests completed to date. Results indicate that virulence on differentials PI88788 and PI54316 is common, with female indices >10% observed for at least one SCN population from 38% of counties sampled. In contrast, no populations with female indices greater than 3% were observed for PI 437654. Further characterization of the HG type will continue in 2010. Information about SCN diversity in Kansas will be used to inform decisions regarding cultivar development and cultivar selection for SCN management. PARTICIPANTS: PI's: Schapaugh, breeder; Todd, nematologist; Trick, plant transformationist; Long, agronomist; Reese, entomologist; Smith, entomologist. Technicians: Dille, Oakley, Essig, Erickson, Kusel Graduate Students: Meng, aphid resistance; Rzodkiewicz, nematology; Brzostowski, pathology. Collaborators: Kimball, agronomist; Maddux, agronomist; Prasad, physiologist, Little, pathologist. TARGET AUDIENCES: Farmers, commodity groups, agricultural businesses, crop consultants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The cultivars developed through this research represent high yielding alternatives for soybean growers in Kansas that offer protection from pathogens and pests. Our germplasm release of K1639-2 and the identification of a gene for aphid resistance in K1621 may be useful to breeders and researchers interested in developing new germplasm with resistance to SBA and SCN. Our management work will enable us to improve recommendations for appropriate management strategies for specific pathogens. For example, our SCN work will improve our ability to accurately predict how a KSU-released or other commercial cultivars will perform across diverse Kansas SCN populations. This knowledge also will inform future decisions about which sources of resistance should be emphasized in the breeding program.
Publications
- Schapaugh Jr., W.T., T. Todd, J. Reese, J. Diaz-Montano, J. Meng, and C.M. Smith. 2010. Registration of K1639-2 soybean germplasm resistant to soybean cyst nematode and soybean aphid. J. of Plant Registrations: 4:1-3.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Phospholipase D [Alpha] (PLD[Alpha])-attenuated transgenic soybean seeds maintained viability when stored for 33 months at room temperature. Germination of transgenic seed stored for 33 months ranged from 30 to 50%. Increased leakage of electrolytes associated with the loss of viability was observed in null-transgenic and background seeds versus transgenic seed. Differences in the ultra-structure of cotyledon tissue were observed between PLD[Alpha]-suppressed soybean and the background cultivar. The loss of viability in the background cultivar was consistent with observations of the plasma membrane being detached from the cell wall complex and disorganization of oil bodies. Stresses caused by extreme temperatures are one agricultural problem that reduces crop productivity in many areas and diverse species. Growth of PLD[Alpha]-attenuated soybean seedlings recovered from extreme heat-shock (45 degrees Celsius) and freezing treatments (-8 degrees Celsius). Study of QTL mapping of soybean aphid (SBA) resistance gene using SSR markers has revealed at least two QTLs controlling SBA resistance in soybean genotype K1621. The mapping population consisted of one hundred and fifty F2:3 families, both parents and highly resistant variety Jackson. Phenotyping of the population was conducted in the greenhouse using a randomized complete block design with three replications. Aphid population was measured on each plant seven days following infestation. The total aphid number indicates the antibiotic resistance level of each plant. Significant variance was observed for aphid number among the F2:3 lines. A genetic linkage map was constructed. One major QTL and one minor QTL have been mapped. The future work will focus on saturating the major QTL region with markers. A search for sources of resistance to the new Ohio biotype of the soybean aphid has been initiated. While none of the Kansas entries tested to date show resistance, there is resistance in several PIs (discovered by other labs). Also, we have found that aphid feeding can induce higher levels of resistance in some genotypes. Future studies, done in collaboration with University of Nebraska scientists, will include gene expression induced by aphid feeding. And, at a more basic level, we have shown that silencing of a particular aphid transcript expressed in aphid salivary glands results in aphids that cannot survive on their host plant (Mutti et al. 2008). Soil samples were collected from 50 SCN-infested commercial soybean fields as part of a survey of the virulence diversity among SCN populations in Kansas. HG Type Tests will be performed for each population. Preliminary results indicate that virulence on the host differentials PI 88788 and PI 548316 (HG Types 2 and 7, respectively) is common. Derived cultivars from the four most commonly used sources of resistance also were included in the evaluations. While female indices on resistance sources generally were relatively low (less than 30%), those for derived cultivars varied widely among SCN populations, approaching 100% in some cases. Overall, resistance sources were not good indicators of the level of resistance found in derived cultivars. PARTICIPANTS: PI's: Schapaugh, breeder; Todd, nematologist; Trick, plant transformationist; Long, agronomist; Reese, entomologist; Smith, entomologist. Technicians: Dille, Oakley, Essig, Erickson, Kusel Graduate Students: Meng, aphid resistance; Walker, heat tolerance; Lee, plant transformation; Rzodkiewicz, nematology; Brzostowski, pathology. Collaborators: Kimball, agronomist; Maddux, agronomist; Prasad, physiologist, Little, pathologist. TARGET AUDIENCES: Farmers, commodity groups, agricultural businesses, crop consultants. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Germplasm with improved traits, unique combinations of traits, or new transgenic traits will have the following potential applications. 1) Our material can provide the foundation for the next cycle of genetic gain by serving as parents to develop new populations and new lines by other public and private breeding programs as well as our own program. 2) Our non-gmo and GMO material can be licensed and released directly as varieties for commercial production. 3) Our transgenic material may enable us to demonstrate to the soybean industry the feasibility of technology that will ultimately provide solutions to problems facing soybean production and soybean utilization. Characterization of virulence spectra for pests such as SCN will provide crucial information for both future variety development and better management practices based on host resistance.
Publications
- Jung Hoon Lee. 2008. Suppression of phospholipase D[Alpha] in soybean. Ph.D. Dissertation. Kansas State University, Manhattan, KS.
- Mutti, N. S., J. Louis, L. K. Pappan, K. Pappan, K. Begum, M.-S. Chen, Y. Park, N. Dittmer, J. Marshall, J. C. Reese, and G. R. Reeck. 2008. A protein from the salivary glands of the pea aphid, Acyrthosiphon pisum, is essential in feeding on a host plant. PNAS 105: 9965-9969.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Three varieties were released in 2007 for non-exclusive commercial licensing. KS4607 is an F4 single plant selection from the cross K1433 x HS93-4118. KS4607 has purple flowers, tawny pubescence, tan pods, indeterminate growth habit, and seeds with black hila. KS4607 is a mid-group IV maturity variety with excellent yield potential and above-average protein content. KS5007sp is an F4 single plant selection from the cross CX1512-8 x K1218. KS5007sp has white flowers, tawny pubescence, tan pods, determinate growth habit, and seeds with brown hila. KS5007sp is an early group V maturity variety with an average linolenic acid concentration of 3 percent. KS5507NRR is a backcross derived Roundup Ready version of the mid-group V Kansas release KS5502N which carries multiple race Soybean Cyst Nematode resistance from Hartwig. K5502N was derived from the cross of Hartwig x KS4895. KS5507NRR has purple flowers, gray pubescence, brown pods at maturity, determinate growth habit, and
seeds with imperfect black hila and shiny seed coats. KS5507NRR is a mid-group V with resistance to Soybean Cyst Nematode Races 2, 3, 4 and 14. One-hundred fifty-two F2:3 families from the cross between K1621 and susceptible genotype KS4202 were evaluated for soybean aphid resistance. Phenotyping of the population was conducted in a greenhouse using a randomized complete block design with three replications. Each family contained up to 22 F3 plants. Aphid number on each plant was counted seven days following infestation. Significant variance was observed for aphid number among the F2:3 lines. The mean aphid number in each F2:3 lines continuously ranged from 6.2 to 42.7. The number of aphid on parents K1621 and KS4202 was 11.3 and 28.8, respectively. To identify genes associated with soybean aphid resistance, two parents were tested with 527 simple sequence repeat markers for polymorphism and mapping of possible QTL's is underway using polymorphic SSR markers. To evaluate the genetic
variability in heat tolerance of pollen germination among soybean lines, maturity group four lines were planted in dryland and irrigated environments in a randomized complete block design with three replications. Pollen was collected from field-grown plants throughout the flowering period from each plot in the early morning and subjected to incubation temperatures of 28, 34, and 38 degrees C in the lab. Pollen germination rates decreased rapidly as incubation temperature increased. Pollen germination rates were highest at 28 degrees C. Genotypes differed significantly in pollen germination rates.
PARTICIPANTS: PI's: Schapaugh, breeder; Todd, nematologist; Trick, plant transformationist; Long, agronomist; Reese, entomologist; Smith, entomologist. Technicians: Dille, Oakley, Essig, Erickson, Kusel Graduate Students: Meng, aphid resistance; Walker, heat tolerance; Lee, plant transformation; Rzodkiewicz, nematology. Collaborators: Kimball, agronomist; Maddux, agronomist; Prasad, physiologist.
TARGET AUDIENCES: Farmers, commodity groups, agricultural businesses, crop consultants.
PROJECT MODIFICATIONS: None
Impacts
Varieties developed through this research represent high yielding alternatives for soybean growers in Kansas and can serve as parents to further advance soybean improvement. Effective strategies will be adopted to manage important soybean pests using genetic resistance. Resistance-based management practices and durability of resistance sources will be incorporated into management recommendations. Extension publications, web sites, news releases, experiment station reports, field days, extension meetings and tours are used to share the results of this project.
Publications
- Kraig L. Roozeboom, William T. Schapaugh, Mitchell R. Tuinstra, Richard L. Vanderlip, and George A. Milliken. 2008. Testing Wheat in Variable Environments: Genotype, Environment, Interaction Effects and Grouping Test Locations. Crop Sci. Accepted in press.
- Diaz-Montano, J., J.C. Reese, W.T. Schapaugh, and L.R. Campbell. 2007. Chlorophyll loss caused by soybean aphid feeding on soybean. J. of Econ. Entomology 100:1657-1662.
- Diaz-Montano, J., J.C. Reese, J. Louis, L.R. Campbell and W.T. Schapaugh. 2007. Feeding behavior by the soybean aphid on resistant and susceptible soybean genotypes. J. of Econ. Entomology 100:984-989.
- Jianye Meng, William Schapaugh, John Reese and C.M. Smith. 2007. Mapping an aphid resistance gene in soybean genotype K1621. ASA-CSSA-SSSA 2007 International Meetings. Abstract.
- Levi Walker, William Schapaugh and P.V.V. Prasad. 2007. Genetic variability in heat tolerance of pollen germination in soybean. ASA-CSSA-SSSA 2007 International Meetings. Abstract.
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Progress 01/01/06 to 12/31/06
Outputs
Two Roundup Ready varieties were released in 2006 for non-exclusive commercial licensing. KS3406RR is a mid-group III, F4 single plant selection from the cross Pioneer 9352////K1235///K1235//Resnik2/40-3-2. KS3406RR has purple flowers, tawny pubescence, brown pods at maturity, indeterminate growth habit, and seeds with brown hila. KS3406RR is susceptible to soybean cyst nematode. KS5306NRR is a mid-group V, backcross derived Roundup Ready version of an early-group V Kansas line K1463 which carries multiple race Soybean Cyst Nematode (SCN) resistance from Hartwig. K1463 was derived from the cross of S88-1934 by N90-516. KS5306RR has purple flowers, tawny pubescence, brown pods at maturity, determinate growth habit, and seeds with brown hila. KS5306NRR possesses resistance or moderate resistance to Races 2, 3, 4 and 14 of SCN, and root-knot nematode. KS5306RR is resistant to Soybean Mosaic Virus, moderately resistant to Sudden Death Syndrome and susceptible to Stem
Canker. Currently, we have a punitive near-isogenic pair of soybean lines in a group V background that differ only in SCN resistance derived from PI88788, the most common source of resistance used in commercial varieties today. We have produced transgenic events that possess a modified Phospholipase gene and field tested the genotypes for a second year in 2006. The phospholipase enzyme activity in the seed of these transgenics has been observed to be 27 to 80% lower than in the control. The phospholipse enzyme activity has impacted the concentration of fatty acids in the mature soybean seed. Over 240 soybean genotypes have been screened for resistance to the soybean aphid. Eleven entries have exhibited resistance. Nine showed antibiosis (effects on growth, development, or reproduction). Two lost less chlorophyll than the susceptible check. Two exhibited both antibiosis and antixenosis (nonpreference). Promising Kansas entries included K1613, K1621, K1639, and K1642. K1639 had both
antibiosis and antixenosis. K1621 and K1639 lost less chlorophyll than the susceptible check. Pioneer 95B97, K1639, Jackson, and Dowling all reduced the amount of time soybean aphids spent in sieve element phase (when aphids can ingest phloem sap from the sieve element) as assessed by the Electrical Penetration Graph technique. We have also succeeded in silencing C002, a gene expressed in aphid salivary glands. Aphids in which the gene has been silenced cannot live on plants. A germplasm release will be made in 2007 of K1639, an aphid, SCN -resistant, high-yielding line.
Impacts
Varieties developed through this research represent high yielding alternatives for soybean growers in Kansas and can serve as parents to further advance soybean improvement. Development of near-isogenic lines differing in SCN resistance will allow us to refine our yield-loss and nematode population models by eliminating genetic differences (other than resistance) as a source of variation in comparisons of resistant and susceptible cultivars. Genetic material developed through the transformation effort may provide solutions to problems facing soybean production and soybean utilization. Effective strategies will be adopted to manage important soybean pests using genetic resistance. Resistance-based management practices and durability of resistance sources will be incorporated into management recommendations. Extension publications, web sites, news releases, experiment station reports, field days, extension meetings and tours are used to share the results of this
project.
Publications
- Diaz-Montano, J., J.C. Reese, W.T. Schapaugh, and L.R. Campbell. 2006. Characterization of antibiosis and antixenosis to the soybean aphid in several soybean genotypes. J. of Econ. Entomology 99:1884-1889.
- Mutti, N.S., Y. Park, J.C. Reese, and G.R. Reeck. 2006. RNAi knockdown of a salivary transcript leading to lethality in the pea aphid, Acyrthosiphon pisum. J. Insect Science. 6.38. (Online at www.insectscience.org/6.38/).
- Stoll, M.E., W.T. Schapaugh, Jr., M.S.Zutara, J.Hu and X.S. Sun. 2006. Genotype and environmental effects on adhesive shear strength in soybean-based adhesives. Crop Sci. 46:2008-2012.
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