Location: Sugarcane Field Station2015 Annual Report
1a. Objectives (from AD-416):
1. Produce high quality seed from designed crosses of improved sugarcane germplasm, and from these seeds, select and release higher yielding sugarcane cultivars with better tolerance and resistance to major biotic and abiotic stresses adapted to Florida conditions. 2. Enhance sugarcane crossing and selection by using molecular methods and markers, devising selection methodologies that accelerate gains from sugarcane breeding, identifying new sources of resistance to biotic and abiotic stresses that can be used as parental clones in sugarcane crossing programs, and characterizing sugarcane and related germplasm for compatibility in crossing. 2.A. Develop methodologies to screen young plants of sugarcane and its relatives for tolerance to short- and moderate-duration flooding. 2.B. Compare and determine methodologies that improve selection efficiency and maximize genetic gains in the Canal Point sugarcane breeding program. 2.C. Develop canopy spectral reflectance algorithms for rapid prediction of sugarcane stalk sucrose content and yield potential to improve early stage genotype selection. 3. Increase yields by improving the tolerance of sugarcane to biotic and abiotic stresses prevalent on the sand and muck soils of Florida through molecular methods and markers and new knowledge of the impact of physiological, morphological, and agronomic traits on these stresses. 3.A. Identify genotypic variation in growth, physiological, and yield traits on sand soils and relationships between these traits. 3.B. Assess the genetics of freeze tolerance in sugarcane and develop stress indices for its field tolerance screening. 3.C. Determine the main and interactive effects on growth and yields of flood duration and drainage depth on recently planted or recently ratooned sugarcane.
1b. Approach (from AD-416):
The primary goal of this project is to improve profits of Florida sugarcane growers by developing more productive and profitable cultivars with improved resistance and tolerance to biotic and abiotic stresses. Most research in genetics, agronomy, and crop physiology focuses on improving the breeding and selection of cultivars to yield more on muck and sand soils and have tolerance or durable resistance to diseases and abiotic stresses. This process will be enhanced through improved knowledge of classic and molecular genetics, identification of important traits for selection, and selection methodologies. A portion of the research aims to improve yields through modified agronomic practices. This section focuses on the research objectives of Glaz, Edmé, and Zhao. We will present each of the two new SYs with their broad research topics when they arrive and expect them to choose specific projects and develop approaches for those projects. The Molecular Biologist will focus substantially on disease resistance through approaches using molecular genetics. The Research Geneticist will focus generally on improving the breeding and selection process. Specific efforts may focus on our new sand program, and this may include the pursuit of links between traditional efforts to breed for increased sucrose yields and newer programs that use sugarcane and related species for cellulosic ethanol and enhanced evaluations of the genotypes that will be brought in by ongoing research from the Miami World Collection. The Molecular Biologist and Research Geneticist are expected to interact with each other, and with colleagues at Canal Point, the University of Florida in Gainesville and its Everglades Research and Education Center in Belle Glade, and with other public and private industry scientists in Florida and Louisiana, and other areas.
3. Progress Report:
The most recent challenge facing sugarcane growers in Florida is the introduction of orange rust and brown rust. Consistent development of disease tolerant and high yield cultivars is important for sugarcane production. True seeds, developed from crosses at Canal Point, Florida, were sent to the ARS cultivar development program in Louisiana. It is estimated that there were 988,151 seeds from 903 crosses sent to Louisiana; and 545,468 seeds from 999 crosses remained in Florida for the regular breeding program; and 34,582 seeds from 81 crosses for the Florida sand-land breeding program. There were 88,863 seedlings from 354 crosses transplanted in the Seeding field in 2015 at Canal Point and approximately 11,664 seedlings (from 50 crosses) transplanted in Clewiston for sand soils. There were 10315 genotypes planted in Stage I and 1627 genotypes planted in Stage II in 2015 at Canal Point. Cultivars developed by ARS occupied more than 90% of the sugarcane acreage in Florida in 2014. This breeding and selection program at Canal Point develops sugarcane cultivars for organic (muck) and sand soils in Florida. Improvements have been made in cultivar selection for sand soils. In 2015, for the fifth consecutive year, all stages of the selection program were planted on sand soils, beginning with the seedling stage. In addition, all stages of the selection program were conducted on muck soils. Two recently released varieties, CP 00-1101 and CP 01-1372 are being expanded rapidly and now are grown on more than 16% of the sugarcane acreage in Florida. In 2015, there were seven new varieties released, CP 07-2320 that is expected to yield well on both muck and sand soils, CP 08-1110 for sand soils only, and other five new cultivars (CP 06-2425, CP 06-2495, CP 06-2964, CP 06-3103, CP 07-1313) for the Townsite (at Clewiston) sand soils only. Most of these new cultivars were resistant to brown rust and orange rust based on inoculations and natural infection tests in the CP breeding program. In research to better understand molecular, physiological, and agronomic bases of biotic and abiotic stress resistance and yield improvement and to help growers meet Best Management Practices, several field and pot studies have been established. Data collection and analyses are in progress.
1. Development of high-yielding sugarcane cultivars for commercial production. The biggest challenge sugarcane growers in Florida are facing is orange rust disease and this disease recently causes considerable yield losses and an increase in input costs of fungicide applications. Therefore, development of new cultivars with disease resistance and high yield is our priority. ARS researchers at Canal Point, FL collaborated with other institutes and released seven new high-yielding sugarcane cultivars with disease resistance / tolerance in June 2015 for growers to use in Florida (especially for sand soils). The seven new cultivars will mitigate negative effects of orange rust and other stresses on sugarcane yield and profits in Florida.
2. Production of high quality seeds for improving probability of elite seedlings. Designing crossing combinations and making crosses based on target traits of parental clones are most important for the Canal Point sugarcane breeding and cultivar development program because optimized crosses can increase genetic contribution to disease resistance and high yields. The ARS researchers at Canal Point refined the crossing strategies and made 1983 crosses for both Florida and Louisiana in the 2014 cross season (November 2014 to February 2015). These crosses resulted in 580,050 seeds for Florida and 988,151 seeds for Louisiana. The high quantity and quality of seeds will increase probability of elite seedlings and clones in other selection stages of the CP program.
Zhao, D. Comstock, J.C., Sandhu, H.S., Glaz, B., Edmé, S.J., Davidson, R.W., Sood, S., Gilbert, R.A., McCorkle, K., and Glynn, N.C. 2015. Registration of ‘CP 06-2400’ Sugarcane. Journal of Plant Registrations. 9:71-77.
Zhao, D., Glaz, B.S., Irey, M., Hu, C. 2015. Sugarcane genotype variation in leaf photosynthesis properties and yield as affected by mill mud application. Agronomy Journal. 107:506-514.
Zhao, D., Li, Y.R. 2014. Climate change impact on sugarcane production in developing countries. In: Li, Y.R.,Rao, G.P., Solomon, S., Yang, L.T., Liu, Z., He, W.Z., Zeng, Y., Tang, Q.Z., Liu, S.Y., Zhou, H., Lu, R.H., editors. Green Technologies for Sustanable Growth of Sugar & Integrated Industries in Developing Countries. Nanning, P. R. China: International Conference on Sugar and Integrated Industries. p. 11-14
Zhao, D., Davidson, W., Baltazar, M., Comstock, J.C. 2015. Field Evaluation of Sugarcane Orange Rust for First Clonal Stage of the CP Sugarcane Cultivar Development Program. American Journal of Agricultural and Biological Science. 10(1):1-11.
Mccord, P.H., Del Blanco, I., Milligan, S., Glaz, B.S., Glynn, N.C., Davidson, R.W., Irey, M. 2014. Sugarcane Genotype Selection on Muck and Sand Soils in Florida — a Case for Dedicated Environments. American Society of Sugar Cane Technologists. 34:28-32.
Leon, R.G., Gilbert, R.A., Comstock, J.C. 2014. Energycane (Saccharum spp. x Saccharum spontaneum L.) Biomass Production, Reproduction, and Weed Risk Assessment Scoring in the Humid Tropics and Subtropics. Agronomy Journal. 107(1):323-329. doi: 10.2134/agronj14.0388.
Nayak, S.N., Song, J., Villa, A., Pathak, B., Ayala Silva, T., Yang, X., Todd, J.R., Glynn, N.C., Kuhn, D.N., Glaz, B.S., Gilbert, R., Comstock, J.C., Wang, J. 2014. Promoting utilization of Saccharum spp. genetic resources though genetic diversity analysis and core collection construction. PLoS One. 9(10):e110856. doi: 10.1371/journal.pone.0110856.