Location: Sugarcane Field Station2018 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:
This is the final report for this project. It has been replaced by project 6030-21000-006-00D, "Development of High-Yielding, Stress Tolerant Sugarcane Cultivars Using Agronomic, Genetic, and Molecular Approaches." The challenges facing the Florida sugarcane growers are still diseases (orange rust, brown rust, smut, leaf scald) and enhancement of sucrose content and yield. Consistent development of disease tolerant and high sugar yield cultivars is important for sustainable sugarcane production. In addition to making efforts for improving the Canal Point (CP) sugarcane breeding and cultivar development programs (CP programs) for Florida, true seeds, developed from crosses at Canal Point, Florida, were sent to the ARS cultivar development program in Houma, Louisiana, in the last five years. It is estimated that in 2013-2018, approximately 237,000 seeds from more than 700 crosses each year were sent to Louisiana; averaged about 175,000 seeds from ~800 crosses remained in Florida for the CP regular (muck-soil) breeding program; and 34,000 seeds from 150 crosses annually made for the Florida CP sand-land breeding program. There were ~83,000 seedlings from 250-300 crosses transplanted in the Seedling field at Canal Point and approximately 18,000 seedlings (from ~70 crosses) transplanted in Clewiston for sand soils in Florida each year. Additionally, a total of 7,200 seedlings per year (from ~180 crosses) were transplanted in two progeny tests at Canal Point. There were 8,500 to 9,000 genotypes planted in Stage I in late January to early February and 1,500 genotypes planted in Stage II in late November at Canal Point, Florida. The CP cultivars developed by ARS occupied more than 90% of the sugarcane acreage in Florida. In 2018, for the eighth consecutive year, all stages of the sand-land selection program were planted on sand soils, beginning with the seedling stage. In addition, all stages of the selection for the muck-soil CP program were conducted on muck soils. In the last 5 years (2013–2018), a total of 27 new sugarcane cultivars were released for Florida growers and industry to commercially use. Of the 27 cultivars, four were well adapted for Florida organic (muck) soils and mineral (sand) soils, six for muck soils only, and 17 for the Florida sand soils. These new released cultivars have been approved and/or are expected to yield well and were resistant/tolerant to most diseases. In research to better understand molecular, genetic, physiological, and agronomic bases of biotic and abiotic stress resistance and yield improvement, to improve data accuracy and selection efficiency for high sucrose content and disease resistance, and to help growers meet Best Management Practices, multiple field and greenhouse studies have been conducted by scientists in Canal Point, Florida. Results have been reported or presented at the professional meetings. Most important research findings have been published or planned to be published in peer reviewed journals.
1. Development of high-yielding and disease resistant sugarcane cultivars for commercial production. The biggest challenge sugarcane growers in Florida are facing is still orange rust and brown rust disease. The rusts recently caused considerable yield losses and an increase in input costs of fungicide applications. Therefore, development of new cultivars with disease resistance/tolerance, high yields, and high profits using different approaches, such as genetics, genomics, agronomy, physiology, and molecular biology, is the priority of the Canal Point (CP) sugarcane breeding and cultivar development programs. ARS researchers at Canal Point, Florida, collaborated with the University of Florida and Florida Sugar Cane League and released 27 new high-yielding sugarcane cultivars with disease resistance/tolerance in 2013-2018 for growers to use in Florida. Four of them were well adapted for Florida organic (muck) soils and mineral (sand) soils, six for muck soils only, and 17 for sand soils. The new cultivars have been mitigating negative effects of brown and orange rusts and other stresses on sugar yields and profits in Florida.