Source: AGRICULTURAL RESEARCH SERVICE submitted to
BIOLOGY AND CONTROL OF SUGARCANE DISEASES BY SCREENING FOR RESISTANT GERMPLASM
Sponsoring Institution
Agricultural Research Service/USDA
Project Status
TERMINATED
Funding Source
USDA INHOUSE
Reporting Frequency
Annual
Accession No.
0406790
Grant No.
(N/A)
Project No.
6625-22000-008-00D
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Feb 7, 2003
Project End Date
Feb 6, 2008
Grant Year
(N/A)
Project Director
COMSTOCK J C
Recipient Organization
AGRICULTURAL RESEARCH SERVICE
(N/A)
CANAL POINT,FL 33438
Performing Department
(N/A)
Non Technical Summary
(N/A)
Animal Health Component
(N/A)
Research Effort Categories
Basic
40%
Applied
60%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
21220201040100%
Knowledge Area
212 - Pathogens and Nematodes Affecting Plants;

Subject Of Investigation
2020 - Sugar cane;

Field Of Science
1040 - Molecular biology;
Goals / Objectives
1) Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques. 2) Evaluate the impact of diseases on sugarcane growth. 3) Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcne production area. 4) Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. Enhance infrastructure and program support in plant pathology in order to more effectively address the threat posed by sugarcane rust, a serious disease threat.
Project Methods
1) Inoculate sugarcane clones used in the breeding and cultivar development programs with pathogens to determine their relative disease resistance, 2) Conduct replicated yield tests to determine the effect of diseases on yield, 3) Sample plants in the variety development program and in grower fields to determine the incidence, 4) Screen progeny of several families of sugarcane for their reaction to sugarcane diseases using standard procedures.

Progress 02/07/03 to 02/06/08

Outputs
Progress Report Objectives (from AD-416) 1) Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques. 2) Evaluate the impact of diseases on sugarcane growth. 3) Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcne production area. 4) Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. Enhance infrastructure and program support in plant pathology in order to more effectively address the threat posed by sugarcane rust, a serious disease threat. Approach (from AD-416) 1) Inoculate sugarcane clones used in the breeding and cultivar development programs with pathogens to determine their relative disease resistance, 2) Conduct replicated yield tests to determine the effect of diseases on yield, 3) Sample plants in the variety development program and in grower fields to determine the incidence, 4) Screen progeny of several families of sugarcane for their reaction to sugarcane diseases using standard procedures. Accomplishments Identification of disease resistant sugarcane cultivars: Disease susceptible sugarcane cultivars must be identified to prevent yield losses to the sugarcane industry. Sugarcane clones in the variety development program were screened for their disease reactions eliminating susceptible clones from being released to growers. These resistant cultivars allow Florida to produce approximately 20% of the sugar consumed in the United States. This research is in support of ARS NP 303 Component 3: Plant Disease Resistance. Problem Statement 3B Disease Resistance in New Germplasm and Varieties. Identification of disease resistant germplasm: Sources of sugarcane yellow leaf virus (SCYLV) and ratoon stunt resistance is necessary for variety development. The level of resistance to SCYLV was higher in historic CL clones (donated to ARS from US Sugar corporation) than that of historic CP clones and may provide a source of resistance. In contrast, the CL clones donated to the USDA-ARS Sugarcane Field Station were more susceptible to ratoon stunt than the CP clones presently in the program and more CL clones will be discarded because of their higher ratoon stunt susceptibility. This research is in support of ARS NP 303 Component 3: Plant Deseae Resistance. Problem Statement 3B Disease Resistance in New Germplasm and Varieties. Technology Transfer Number of New CRADAS and MTAS: 6

Impacts
(N/A)

Publications

  • Comstock, J.C., Tai, P.Y.P., Miller, J.D. 2007. Identification of parents for breeding sugarcane yellow leaf and ratoon stunt resistant cultivars. International Society of Sugar Cane Technologists Proceedings. 26:978-987.
  • Gilbert, R.A., Gallo-Meagher, M., Comstock, J.C., Miller, J.D., Jain, M., Abouzid, A. 2005. Agronomic evaluation of sugarcane lines transformed for resistance to sugarcane mosaic virus strain E. Crop Science. 45:2060-2067
  • Shine, J.M., Comstock, J.C., Dean, J.L. 2005. Comparison of five isolates of sugarcane rust and differential reaction on six sugarcane clones. Sugar Cane International 23:24-29.


Progress 10/01/05 to 09/30/06

Outputs
Progress Report 1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? Why does it matter? Sugarcane diseases can adversely affect sugar production and consequently need to be controlled to maintain a viable sugarcane industry. Presently, sugarcane yellow leaf infects over 85% of the plants grown commercially in Florida and causes 5 to 10 % yield loss costing the Florida sugarcane industry millions. There are only limited sources of resistance and there is not a method to screen large numbers of sugarcane clones for their reaction to the aphid transmitted sugarcane yellow leaf virus. Other sugarcane diseases (brown rust, smut, ratoon stunt, leaf scald and mosaic) also pose threats to the industry due to changes in pathogenic races and strains. To maintain an economically viable sugarcane industry a steady supply of disease-resistant high-yielding cultivars are absolutely essential. The United States has to import sugar since its production does not meet its consumers needs. To ensure the US consumers of a constant supply of this food commodity at its low price the domestic sugarcane industry requires disease-resistant high-yielding cultivars. Since there is not an economic incentive for private companies to develop sugarcane cultivars because sugarcane is vegetatively propagated it is important for the USDA-ARS to supply them. The project has four specific goals: 1) Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques, 2) Evaluate the impact of diseases on sugarcane growth, 3) Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area, and 4) Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. The research to be undertaken fall under National Program 303 Plant Diseases and addresses goals 5.2 (Germplasm Disease Resistance Screening) : 5.3 (Germplasm Breeding for Commercial Release); 5.1 (Germplasm Collection in cooperation with CRIS 6631-21000-088-00D at the Subtropical Horticultural Research Station in Miami; 5.5 (Identification of Gene Control Regions in Sugarcane that could be useful for Bioengineering); 4. 1 (Identification of Factors in Pathogens that Contribute to Ability to Cause Disease); 4.2 (Defining Important Parameters of Epidemics) and 1.1 (Development and Standardization of Tools for Diagnosis and Detection of Indigenous, Exotic, and Emerging Diseases). Achieving these goals will provide an economic means of controlling diseases of sugarcane that are environmentally friendly and will directly benefit sugarcane growers and sugar consumers. Information learned will benefit scientists by assisting them to develop disease resistant varieties and increase their understanding of sugarcane diseases. The anticipated products are: 1) new high yielding disease resistant sugarcane cultivars for commercial growers, 2) the development of new diseases screening techniques and procedures, 3) a better understanding of the current impact of diseases on yield and 4) the development of appropriate reference populations to develop molecular markers. 2. List by year the currently approved milestones (indicators of research progress) Year 1 (FY 2003) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by yellow leaf virus in two trials (harvest, plant and first ratoon crops); ratoon stunting disease in two trials (harvest, plant and first ratoon crops) and establish a yield trial to determine mosaic losses. 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. Characterize individuals of Green German x Ind 81-146 population for their reaction to yellow leaf virus and ratoon stunting disease; individuals of CP 80-1827 x CP 80-1827 population for their reaction to yellow leaf virus, ratoon stunting disease and rust; and Green German x Coimbatore for their reaction to ratoon stunting disease. Year 2 (FY 2004) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by yellow leaf virus in trials (harvest first ratoon crop); ratoon stunting disease in yield trials (harvest, first ratoon crop) and mosaic (harvest plant crop). 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. The disease reactions of individuals in populations evaluated in FY 2003 will be verified. Year 3 (FY 2005) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by mosaic (harvest, first ratoon crop). 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. The yellow leaf reactions of individuals in Green German x Coimbatore population will be evaluated. Rust reactions of individuals of Green German x Ind 81-146 and CP 94-1200 x CP 92-1167 populations will be evaluated. Year 4 (FY 2006) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate the effect of diseases on recently released cultivars. 3. Re-evaluate monitoring program. 4. Verify the yellow leaf reactions of individuals in Green German x Coimbatore population. Rust reactions of individuals evaluated in 2005 will be verified. Year 5 (FY 2007) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate the effect of diseases on recently released cultivars. 3. Re-evaluate monitoring program. 4. Disease reactions of individuals in new populations will be evaluated for molecular research. 4a List the single most significant research accomplishment during FY 2006. Yellow leaf virus resistant sugarcane clones were identified and will serve as parental clones to assist develop resistance to this economically important pathogen. 4b List other significant research accomplishment(s), if any. Sugarcane clones in the variety development program were screened for their disease reactions eliminating susceptible clones from being released to growers. Due to changes in pathogens affecting sugarcane in Florida a constant stream of disease resistant cultivars is required. These resistant cultivars allow Florida to produce approximately 20 % of the sugar consumed in the United States. 5. Describe the major accomplishments to date and their predicted or actual impact. The major accomplishment of the project is the continual release of new cultivars resistant to most diseases and if not, with only moderate susceptibility. Since 2002, five cultivars, CP 96-1252, CP 96-1602, CP 97-1944, CP 97-1989 and CP 98-1029 have been released for commercial production. With the constant stream of new disease-resistant cultivars that are high yielding production has remained high across the industry. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? 1. Ratoon stunt and yellow leaf of sugarcane reduce sugarcane yields. This information was presented to Sugarcane Pathologists from 14 different countries at the Sugarcane Pathology Workshop of the International Society of Sugarcane Technologists. 2. Ratoon stunt resistance can be developed in sugarcane. This information was presented to Sugarcane Breeders from 14 different countries at the Sugarcane Breeders and Germplasm Workshop of the International Society of Sugarcane Technologists. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Log Number 195057. Comstock, Jack C. and Sood, S. Breeding for ratoon stunt resistance at Canal Point, Florida. Presented at the International Society of Sugar Cane Technologists Sugarcane Breeding and Germplasm Workshop. Guayaquil, Ecuador May 2, 2006. Log Number 186251. Comstock, Jack C. Ratoon stunt and yellow leaf effects on sugarcane yields. Presented at the International Society of Sugar Cane Technologists Sugarcane Pathology Workshop. Petit-Bourg, Guadeloupe, French West Indies. January 25, 2006. Log Number 186205. Comstock, Jack C. and Gilbert, Robert A. 2005. Sugarcane Yellow Leaf Virus. In: R. A. Gilbert (ed) Florida Sugarcane Handbook: University of Florida Extension, IFAS. http://edis.ifas.ufl. edu/ MENU_SC Comstock, J. C. Review of the CP Cultivar Development Program presented at the USDA-ARS Sugarcane Field Station Field Day, at Canal Point, December 16, 2005. Comstock, J. C. USDA-ARS Sugarcane Field Station presented to approximately 20 High School Teachers enrolled in an Agroecology Program in Environmental Studies, Florida International University.

Impacts
(N/A)

Publications

  • Ming, R., P. H. Moore, K. K. Wu, A. DHont, J. C. Glaszmann, T. L. Tew, T. E. Mirkov, J. da Silva, J. Jifon, M. Rai, R. J. Schnell, S. M. Brumbley, P. Lakshmanan, J. C. Comstock, A. H. Paterson Sugarcane Improvement through Breeding and Biotechnology. In (J Janick ed.) Plant Breeding Reviews vol 27: 15-118. 2006.
  • Glynn, N.C., Comstock, J.C., Sood, S.G., Dang, P.M., Chaparro, J. 2006. Exploring gene analogues as markers for disease resistance: sequence isolation and characterization. American Society of Sugar Cane Technologists 26:46 2006


Progress 10/01/04 to 09/30/05

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Sugarcane diseases can adversely affect sugar production and consequently need to be controlled to maintain a viable sugarcane industry. Knowledge of the effect and extent of diseases on sugarcane cultivars grown is required to limit losses. Currently, disease resistance is identified based on natural infection and data from inoculated tests; however, molecular markers for resistance offer an opportunity for marker assisted selection for disease resistance and additional populations require characterization for research. Since disease resistance is the most cost effective, environmentally safe and user friendly method of disease control, resistant cultivars are being developed. The project has four specific goals: 1) Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques, 2) Evaluate the impact of diseases on sugarcane growth, 3) Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area, and 4) Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. The research to be undertaken fall under National Program 303. Plant Diseases and addresses goals 5.2 (Germplasm Disease Resistance Screening) : 5.3 (Germplasm Breeding for Commercial Release); 5.1 (Germplasm Collection in cooperation with CRIS 6631-21000-088-00D at the Subtropical Horticultural Research Station in Miami; 5.5 (Identification of Gene Control Regions in Sugarcane that could be useful for Bioengineering); 4. 1 (Identification of Factors in Pathogens that Contribute to Ability to Cause Disease); 4.2 (Defining Important Parameters of Epidemics) and 1.1 (Development and Standardization of Tools for Diagnosis and Detection of Indigenous, Exotic, and Emerging Diseases). Achieving these goals will provide an economic means of controlling diseases of sugarcane that are environmentally friendly and will directly benefit sugarcane growers and sugar consumers. Information learned will benefit scientists by assisting them to develop disease resistant varieties and increase their understanding of sugarcane diseases. The anticipated products are: 1) new high yielding disease resistant sugarcane cultivars for commercial growers, 2) the development of new diseases screening techniques and procedures, 3) a better understanding of the current impact of diseases on yield and 4) the development of appropriate reference populations to develop molecular markers. 2. List the milestones (indicators of progress) from your Project Plan. Year 1 (FY 2003) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by yellow leaf virus in two trials (harvest, plant and first ratoon crops); ratoon stunting disease in two trials (harvest, plant and first ratoon crops) and establish a yield trial to determine mosaic losses. 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. Characterize individuals of Green German x Ind 81-146 population for their reaction to yellow leaf virus and ratoon stunting disease; individuals of CP 80-1827 x CP 80-1827 population for their reaction to yellow leaf virus, ratoon stunting disease and rust; and Green German x Coimbatore for their reaction to ratoon stunting disease. Year 2 (FY 2004) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by yellow leaf virus in trials (harvest first ratoon crop); ratoon stunting disease in yield trials (harvest, first ratoon crop) and mosaic (harvest plant crop). 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. The disease reactions of individuals in populations evaluated in FY 2003 will be verified. Year 3 (FY 2005) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate disease losses caused by mosaic (harvest, first ratoon crop). 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. 4. The yellow leaf reactions of individuals in Green German x Coimbatore population will be evaluated. Rust reactions of individuals of Green German x Ind 81-146 and CP 94-1200 x CP 92-1167 populations will be evaluated. Year 4 (FY 2006) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate the effect of diseases on recently released cultivars. 3. Re-evaluate monitoring program. 4. Verify the yellow leaf reactions of individuals in Green German x Coimbatore population. Rust reactions of individuals evaluated in 2005 will be verified. Year 5 (FY 2007) 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). 2. Evaluate the effect of diseases on recently released cultivars. 3. Re-evaluate monitoring program. 4. Disease reactions of individuals in new populations will be evaluated for molecular research. 3a List the milestones that were scheduled to be addressed in FY 2005. For each milestone, indicate the status: fully met, substantially met, or not met. If not met, why. 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). Milestone Fully Met 2. Evaluate disease losses caused by mosaic (harvest, first ratoon crop). Milestone Not Met Redirection of Research focus due to change in priorities 3. Determine the disease incidence of yellow leaf and mosaic in all stages of the cultivar development program and in 40 grower fields that were planted with disease-free seedcane derived via meristem tissue. Milestone Substantially Met 4. The yellow leaf reactions of individuals in Green German x Coimbatore population will be evaluated. Milestone Fully Met 3b List the milestones that you expect to address over the next 3 years (FY 2006, 2007, and 2008). What do you expect to accomplish, year by year, over the next 3 years under each milestone? FY 2006 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). The screening of clones in the cultivar development program will identify raoon stunt, smut, leaf scald and mosaic resistant clones for consideration for commercial production in Florida. 2. Evaluate the effect of diseases on recently released cultivars. This has been completed with the exception of determining losses due to syngeristic effects between yellow leaf and ratoon stunt on sugarcane which is not technically possible. Research will be redirected to associating molecular markers with resistance using populations developed under number 4. 3. Re-evaluate monitoring program. Disease incidence will be determined in clones in the cultivar development program eliminating susceptible clones. Growers fields will be surveyed to determine disease incidences. 4. Verify the yellow leaf reactions of individuals in Green German x Coimbatore population. The characterized populations will permit the association of molecular markers with disease resistance for use in the variety development program. The use of markers will result in more rapid and accurate selection of resistant cultivars. FY 2007 1. Screen clones in the cultivar development program for disease resistance to ratoon stunt (Stages II through IV), and mosaic, leaf scald and smut (Stage III inc. and Stage IV). The screening of clones in the cultivar development program will identify raoon stunt, smut, leaf scald and mosaic resistant clones for consideration for commercial production in Florida. 2. Re-directed goal of associating molecular markers with resistance using populations developed under objective 4. The use of markers will result in more rapid and accurate selection of resistant cultivars. 3. Re-evaluate monitoring program. Disease incidence will be determined in clones in the cultivar development program eliminating susceptible clones. Growers fields will be surveyed to determine disease incidences. 4. Disease reactions of individuals in new populations will be evaluated for molecular research. The characterized populations will permit the association of molecular markers with disease resistance for use in the variety development program. The use of markers will result in more rapid and accurate selection of resistant cultivars. 4a What was the single most significant accomplishment this past year? The individual progeny of two sugarcane populations were characterized for their reaction to sugarcane rust and ratoon stunt. The rust and ratoon stunt reactions of individuals of each population ranged from completely resistant to extremely susceptible. These populations are being used to associate molecular markers with rust resistance. 4b List other significant accomplishments, if any. Sugarcane clones in the variety development program were screened for their disease reactions eliminating susceptible clones from being released to growers. Due to changes in pathogens affecting sugarcane in Florida a constant stream of disease resistant cultivars is required. These resistant cultivars allow Florida to produce approximately 20 % of the sugar consumed in the United States. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. The major accomplishment of the project is the continual release of new cultivars resistant to most diseases and if not, with only moderate susceptibility. Since 2002, five cultivars, CP 96-1252, CP 96-1602, CP 97-1944, CP 97-1989 and CP 98-1029 have been released for commercial production. With the constant stream of new disease-resistant cultivars that are high yielding production has remained high across the industry. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Two sugarcane cultivars were released and available in the fall of 2004 and one cultivar released this year will be available to growers in the fall of 2005. The impact of these cultivars will not be until 5 to 10 years since sugarcane cultivars are vegetatively propagated, it is not until five years after release that substantial acreages can be grown. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: List your peer reviewed publications below). Log Number 180182. Comstock, J. C. and Sood, S. G., and McCorkle, K. 2005. Characterization of sugarcane populations for disease reactions for use in molecular marker research. Sugar J. 68:19. Presentation at the annual meeting of the American Society of Sugar Cane Technologist. June 14, 2005. Log. Number 165387. Comstock, J. C., Miller, J. D., Schnell, R. J. and Ayala Silva, T. 2005. Sugarcane yellow leaf virus in the world collection of sugarcane and related grasses at Miami, Florida. XXV. Proc. International Society Sugar Cane Technologists 2:691-694. Presentation at the Congress of the International Society of Sugar Cane Technologist. February 1, 2005. Log number 158420. Shine, J. M., Comstock, J. C. and Dean, J. L. 2005. Comparison of five isolates of sugarcane rust and differential reaction on six sugarcane clones. XXV. Proc. International Society Sugar Cane Technologists 2:638-647.

Impacts
(N/A)

Publications

  • Flynn, J., Powell, G., Perdomo, R., Montes, G., Quebedeaux, K., Comstock, J.C. 2005. Comparison of yield parameters and disease incidence of traditional seedcane sources and kleentek, a commercial tissue-culture based seedcane. J.American Society of Sugar Cane Technologists. 25:88-100.


Progress 10/01/03 to 09/30/04

Outputs
1. What major problem or issue is being resolved and how are you resolving it (summarize project aims and objectives)? How serious is the problem? What does it matter? Sugarcane diseases can adversely affect sugar production and consequently need to be controlled to maintain a viable sugarcane industry. Knowledge of the effect and extent of diseases on sugarcane cultivars grown is required to limit losses. Currently, disease resistance is identified based on natural infection and data from inoculated tests; however, molecular markers for resistance offer an opportunity for marker assisted selection for disease resistance and additional populations require characterization for research. Since disease resistance is the most cost effective, environmentally safe and user friendly method of disease control, resistant cultivars are being developed. The project has four specific goals: 1) Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques, 2) Evaluate the impact of diseases on sugarcane growth, 3) Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area, and 4) Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. The research to be undertaken falls under National Program 303 : Plant Diseases and addresses goals 5.2 (Germplasm Disease Resistance Screening) : 5.3 (Germplasm Breeding for Commercial Release); 5.1 (Germplasm Collection in cooperation with CRIS 6631-21000-088-00D at the Subtropical Horticultural Research Station in Miami; 5.5 (Identification of Gene Control Regions in Sugarcane that could be useful for Biogenineening); 4. 1 (Identification of Factors in Pathogens that Contribute to Ability to Cause Disease); 4.2 (Defining Important Parameters of Epidemics) and 1.1 (Development and Standardization of Tools for Diagnosis and Detection of Indigenous, Exotic, and Emerging Diseases). Achieving these goals will provide an economic means of controlling diseases of sugarcane that are environmentally friendly and will directly benefit sugarcane growers and sugar consumers. Information learned will benefit scientists by assisting them to develop disease resistant varieties and increase their understanding of sugarcane diseases. The anticipated products are: 1) new high yielding disease resistant sugarcane cultivars for commercial growers, 2) the development of new disease screening techniques and procedures, 3) better understanding of the current impact of diseases on yield and 4) the development of appropriate reference populations to develop molecular markers. 2. List the milestones (indicators of progress) from your Project Plan. Objective 1: Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques. a. Year 2 (FY 04) Stage II Ratoon stunt 1000 clones in the CP 03 Series. Stage III Ratoon stunt 35 clones in the CP 02 Series. Stage III inc. Ratoon stunt, mosaic, leaf scald and smut 40 clones in CP 01 Series. Stage IV Ratoon stunt, mosaic, and leaf scald 14 clones in CP 00 Series. b. Year 3 (FY 05) Stage II Ratoon stunt 1000 clones in the CP 04 Series. Stage III Ratoon stunt 35 clones in the CP 03 Series. Stage III inc. Ratoon stunt, mosaic, leaf scald and smut 40 clones in CP 02 Series. Stage IV Ratoon stunt, mosaic, and leaf scald 14 clones in CP 01 Series. c. Year 4 (FY 06) Stage II Ratoon stunt 1000 clones in the CP 05 Series. Stage III Ratoon stunt 35 clones in the CP 04 Series. Stage III inc. Ratoon stunt, mosaic, leaf scald and smut 40 clones in CP 03 Series. Stage IV Ratoon stunt, mosaic, and leaf scald 14 clones in CP 02 Series. d. Year 5 (FY 07) Stage II Ratoon stunt 1000 clones in the CP 06 Series. Stage III Ratoon stunt 35 clones in the CP 05 Series. Stage III inc. Ratoon stunt, mosaic, leaf scald and smut 40 clones in CP 04 Series. Stage IV Ratoon stunt, mosaic, and leaf scald 14 clones in CP 03 Series. Objective 2. Evaluate the impact of diseases on sugarcane growth. a. Year 2 (FY 04) a. Harvest yield test to determine effect of sugarcane yellow leaf virus (first ratoon crop). b. Harvest yield test to determine effect of ratoon stunt (first ratoon crop). c. Harvest mosaic yield test. b. Year 3 (FY 05) a. Establish tests to determine effect of diseases on recently released cultivars. Exact experiments will depend on disease ratings and disease incidence. c. Year 4 (FY 06) a. Establish tests to determine effect of diseases on recently released cultivars. Exact experiments will depend on disease ratings and disease incidence. d. Year 5 (FY 07) a. Establish tests to determine effect of diseases on recently released cultivars. Exact experiments will depend on disease ratings and disease incidence. Objective 3. Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area. a. Year 2 (FY 04 a. Sample clones in all stages of the breeding program for presence of sugarcane yellow leaf virus. b. Sample plants in 40 grower fields planted using disease free plants for presence of sugarcane yellow leaf virus. c. Sample plants in 40 grower fields planted using disease free plants for presence of sugarcane mosaic virus. b. Year 3 (FY 05) a. Re-evaluate monitoring program. c. Year 4 (FY 06) a. Re-evaluate monitoring program. d. Year 5 (FY 07) a. Re-evaluate monitoring program. Objective 4. Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. a. Year 2 (FY 04) a. Evaluate progeny of Green German x Coimbatore for reaction to sugarcane yellow leaf virus. b. Year 3 (FY 05) a. Evaluate progeny of Green German x Coimbatore for reaction to sugarcane yellow leaf virus. c. Year 4 (FY 06) a. Evaulate progeny of other crosses for reaction to diseases. d. Year 5 (FY 07) a. Evaulate progeny of other crosses for reaction to diseases. 3. Milestones: Objective 1: Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques. Stage II Ratoon stunt 1000 clones in the CP 03 Series. Stage III Ratoon stunt 35 clones in the CP 02 Series. Stage III inc. Ratoon stunt, mosaic, leaf scald and smut 40 clones in CP 01 Series. Stage IV Ratoon stunt, mosaic, and leaf scald 14 clones in CP 00 Series. All disease screenings were completed and the information assisted in the development of resistant sugarcane cultivars for growers. Objective 2. Evaluate the impact of diseases on sugarcane growth. Year 2 (FY 04) b. Harvest yield test to determine effect of sugarcane yellow leaf virus (first ratoon crop). c. Harvest yield test to determine effect of ratoon stunt (first ratoon crop). d. Harvest mosaic yield test. The mosaic yield test was not established because insufficient plants infected with sugarcane mosaic virus of two commercial cultivars were not obtained either by inoculation or natural infection probably because of their level of resistance. The two yield trials evaluating the effect of sugarcane yellow leaf virus and ratoon stunt were harvested. An additional trial evaluating ratoon stunt was harvested. Objective 3. Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area. Year 2 (FY 04) a. Sample clones in all stages of the breeding program for presence of sugarcane yellow leaf virus. b. Sample plants in 40 grower fields planted using disease free plants for presence of sugarcane yellow leaf virus. c. Sample plants in 40 grower fields planted using disease free plants for presence of sugarcane mosaic virus. All were completed. Objective 4. Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. Year 2 (FY 04) a. Evaluate progeny of Green German x Coimbatore for reaction to sugarcane yellow leaf virus. The progeny were evaluated for their reaction to sugarcane yellow leaf virus. In addition, progeny of the following sugarcane crosses were evaluated for their reactions to the indicated diseases: Green German x Ind 81-146 for rust; CP 94-1200 x CP 92-1167 for rust; Green German x SES 208 for ratoon stunt; and CP 80-1827 x CP 80-1827 (selfed) for ratoon stunt. Individuals from each cross were selected that gave either extreme susceptible or resistant reaction to the indicated disease. These selected individuals will be bulked and used in bulk segregation analysis for the identification of molecular markers associated with disease resistance. In addition, sugarcane clones in the World Collection of Sugarcane and Related Grasses in Miami were assayed for the presence of sugarcane yellow leaf virus. Differences in the incidence of the virus occurred in the different species of Saccharum. b. List the milestones (from the list in Question #2) that you expect to address over the next 3 years (FY 2005, 2006, & 2007). What do you expect to accomplish, year by year, over the next 3 years under each milestone. Objective 1: Screen sugarcane clones and germplasm for resistance to ratoon stunting disease, leaf scald, mosaic, smut and eye spot using proven techniques. In each year 2005, 2006, and 2007 sugarcane clones in the cultivar development program will be screened to identify and quantify susceptibility thus ensuring that only clones with acceptable disease reactions will be considered for commercial production in Florida. Objective 2. Evaluate the impact of diseases on sugarcane growth. FY 2005 through 2007 A series of yield trials will be installed that will evaluate the effect of diseases on the most important cultivars that have been recently released. Cultivars that appear to have any disease concerns will be emphasized. This information will determine the losses, if any, of diseases on newly released sugarcane cultivars and allow growers to make appropriate changes. Objective 3. Determine the incidence and spread of diseases within the breeding and variety development populations and grower fields in the sugarcane production area. a. Year 3 (FY 05) Re-evaluate monitoring program. If a disease appears to have a significant incidence in either the breeding program or growers fields, then it will be monitored to quantify incidence and impact in grower fields, and resistant clones in the breeding program will be identified. b. Year 4 (FY 06) a. Re-evaluate monitoring program. c. Year 5 (FY 07) a. Re-evaluate monitoring program. Objective 4. Develop populations of sugarcane clones appropriate for detecting molecular markers to select resistant genes. a. Year 3 (FY 05) a. Evaluate progeny of Green German x Coimbatore for reaction to sugarcane yellow leaf virus. The reaction of individual clones of this cross will be determined for use in molecular studies to associate markers with resistance. The use of markers will result in more rapid and accurate selection of resistant cultivars. b. Year 4 (FY 06) a. Evaluate progeny of other crosses for reaction to diseases. Determining the reactions of progeny of other crosses for rust, sugarcane yellow leaf and ratoon stunt will aid in the development and verification of markers. The use of markers will result in more rapid and accurate selection of resistant cultivars. c. Year 5 (FY 07) a. Evaluate progeny of other crosses for reaction to diseases. Determining the reactions of progeny of other crosses for rust, sugarcane yellow leaf and ratoon stunt will aid in the development and verification of markers. The use of markers will result in more rapid and accurate selection of resistant cultivars. b. Significant activities that support special target populations. None d. Progress Report opportunity to submit additional programmatic information to our Area Office and NPS (optional for all in-house (D) projects and the projects listed in Appendix A; mandatory for all other subordinate projects. None 4. What were the most significant accomplishments this past year? It was determined that two diseases of sugarcane, yellow leaf virus and ratoon stunt, cause yield losses in the cultivars presently grown commercially in Florida. This was the first report of the effect of the sugarcane yellow leaf virus, a widespread virus, on yield in Florida. This year, the second year of yield data was completed for three trials determining the effect of ratoon stunt and one trial determining the effect of yellow leaf virus. With this new information Florida growers will make better economic decisions on which cultivars to grow and whether to purchase disease free planting material of several cultivars. B. Other significant accomplishments, if any. Preliminary results indicated the association of two molecular markers for the reaction of sugarcane to sugarcane yellow leaf virus. However, the markers do not appear to be closely linked to the resistance gene. Analyses were conducted to evaluate 216 primers (primers identify segments of DNA) on parental clones and groups of susceptible and resistant progeny of a cross between two wild relatives of sugarcane. The association has to be verified using additional clones of the original and other populations of sugarcane. If their association is verified these markers may assist in finding markers closer to the resistant gene. C. None D. None 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. The major accomplishment of the project is the continual release of new cultivars resistant to most diseases and if not, with mild disease susceptibility quantified. In 2003, two new cultivars, CP 96-1252 and CP 96-1602, were registered for commercial production in Florida. These cultivars will offer growers alternative choices to plant and add diversity of cultivars. 6. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Two new sugarcane cultivars, CP 97-1944 and CP 97-1989, became available for commercial use by farmers in Florida. Because sugarcane cultivars are vegetatively propagated, it is not until five years after release that substantial acreages can be grown. 7. List your most important publications in the popular press and presentations to organizations and articles written about your work. Comstock, J. C., Chaparro, J., Tai, P. Y. P., Edme, S. J., McCorkle, K. M. , and Miller, J. D. The association of two microsatellite markers with resistance to sugarcane yellow leaf virus. Presentation to the Plant and Animal Genome Conference January 11, 2004.

Impacts
(N/A)

Publications

  • Comstock, J.C., Chaparro, J., Tai, P.Y., Edme, S.J., Mccorkle, K.M., Miller, J.D. 2004. The association of microsatellite markers with resistance to sugarcane yellow leaf virus. Annual International Plant & Animal Genome Conference.
  • Comstock, J.C., Miller, J.D. 2004. Ratoon stunt effects on yields of sugarcane. American Society Of Sugar Cane Technologists. 24:106.
  • Glaz, B.S., Edme, S.J., Morris, D.R., Comstock, J.C., Gilbert, R.A. 2004. Water table and sugarcane: a review of recent research. Sugar Journal. Vol. 67(1):16
  • Flynn, J., Quebedeaux, K., Powell, G., Montes, G., Perdomo, R., Comstock, J.C. 2004. Comparison of yield parameters and disease incidence of traditional seedcane sources and kleentek, a commercial tissue-culture based seedcane. American Society Of Sugar Cane Technologists. 24:107.


Progress 10/01/02 to 09/30/03

Outputs
1. What major problem or issue is being resolved and how are you resolving it? Sugarcane diseases can adversely affect sugar production and consequently need to be controlled to maintain a viable sugarcane industry. Since disease resistance is the most cost effective, environmentally safe and user friendly method of disease control, resistant cultivars are being developed. 2. How serious is the problem? Why does it matter? Sugarcane diseases routinely impact commercial production. In 1986, ratoon stunting disease of sugarcane caused a 5% yield loss industry wide in Florida. Currently, because of selection for resistance the commercially grown cultivars are more resistant to this disease. For successful commercial production, cultivars must be resistant to several diseases. When new strains of pathogens arise the threat is severe and susceptible cultivars will suffer yield losses. Furthermore, the impact of diseases on the cultivar development program is great since a single disease such as leaf scald can cause an annual loss of 20% of the clones in the program which negatively impacts cultivar development. 3. How does it relate to the National Program(s) and National Program Component(s) to which it has been assigned? The research detects new diseases and pathogenic strains, evaluates effects of diseases, develops disease screening techniques, and selects sugarcane cultivars resistant to diseases which are components of the Plant Diseases National Program, 303. 4. What were the most significant accomplishments this past year? A. A high incidence of sugarcane yellow leaf virus (SCYLV) occurs in commercially grown sugarcane in Florida and the extent of yield losses is not known. Two yield tests were established comparing the yields between SCYLV infected and virus-free plants. The analysis of the combined data for five cultivars determined that the yield parameters were significantly higher (up to 11 % higher) in the virus-free plants over the SCYLV-infected plants. This indicates that the use of virus-free planting material will increase yields. B-1. Disease screening of sugarcane clones in the Canal Point, Florida sugarcane cultivar development program was conducted to eliminate susceptible clones and reduce the threat of future epidemics. Sugarcane clones were screened for disease resistance to ratoon stunting disease, leaf scald, mosaic and smut at multiple stages of the program. At each stage, resistant clones were identified and advanced. Two clones with adequate disease resistance and superior agronomic characteristics were identified and released to growers for potential commercial production. B-2. Natural infection of sugarcane clones in the variety development program by sugarcane yellow leaf virus (SCYLV) occurs and resistance needs to be developed. The incidence of SCYLV-infection was determined based on all clones and by each family (biparental cross) for clones in the variety development program. The overall incidence of SCYLV- infection was 30% where individual families ranged from 7 to 40 %. Resistance to SCYLV should be increased by emphasizing biparental crosses that have given lower incidences of SCYLV in progenies. 5. Describe the major accomplishments over the life of the project, including their predicted or actual impact. A ratoon stunting disease resistance screening program was initiated resulting in increasing the general level of resistance of sugarcane clones and in resistant cultivars being released to growers. From 1992 through 2003, 22 cultivars were released from the program and 13 were either resistant or moderately resistant. The ratoon resistant cultivars should increase the sugar industry's production and decrease the pathogen's spread and overall inoculum. 6. What do you expect to accomplish, year by year, over the next 3 years? For FY 2004, sugarcane clones in the cultivar development program at Canal Point, Florida will be evaluated for disease resistance to smut, leaf scald, sugarcane mosaic, eye spot, and ratoon stunting diseases. The effect of ratoon stunting disease on yield will be evaluated in the first ratoon crop. Resistant gene analogs will be evaluated for their association with resistance to sugarcane yellow leaf virus, rust and ratoon stunting disease. Sugarcane clones in the World Collection of Sugarcane and Related Grasses will be evaluated for the presence of sugarcane yellow leaf virus and the ratoon stunting disease pathogen. For FY 2005, sugarcane clones in the cultivar development program at Canal Point, Florida will be evaluated for disease resistance to smut, leaf scald, sugarcane mosaic, eye spot, and ratoon stunting diseases. Potential molecular markers will be evaluated using wild sugarcane clones and a diverse collection of domestic and foreign commercial cultivars. New populations of sugarcane clones will be evaluated for their disease reaction to sugarcane mosaic for molecular marker research to associate markers with mosaic resistance. Tests to determine if there are synergistic effects between yellow leaf virus and ratoon stunting disease will be initiated. For FY 2006, sugarcane clones in the cultivar development program at Canal Point, Florida will be evaluated for disease resistance to smut, leaf scald, sugarcane mosaic, eye spot, and ratoon stunting diseases. The evaluation of dual infection of yellow leaf virus and ratoon stunting disease will be completed. Microsatillites and other resistance gene analogs will be evaluated for their association with sugarcane clones to mosaic resistance. 7. What science and/or technologies have been transferred and to whom? When is the science and/or technology likely to become available to the end- user (industry, farmer, other scientists)? What are the constraints, if known, to the adoption and durability of the technology products? Two disease-resistant sugarcane cultivars, CP 96-1252 and CP 96-1602, were released to growers. These cultivars will offer growers another alternative for commercial production. Two disease-resistant sugarcane cultivars, CP 96-1252 and CP 96-1602, were released to growers. These cultivars will offer growers another alternative for commercial production. 8. List your most important publications in the popular press and presentations to organizations and articles written about your work. (NOTE: This does not replace your peer-reviewed publications listed below). Popular press: Comstock, J.C. Factors to consider in handling clean seedcane. 2003. Florida Sugar Cane League Informational Bulletin. Pages 1-2. Presentations: Comstock, J.C. Planting and harvesting considerations for handling disease-free sugarcane. 2003. Agricultural Forum. Sponsored by the Sugar Cane Growers Cooperative of Florida in Belle Glade, Florida. Oral presentation to 100 sugarcane technologists. Comstock, J.C. and Miller, J.D. Sugarcane yellow leaf virus spread in Florida. 2003. American Phytopathological Society Caribbean Division Annual Meeting. Oral presentation. Comstock, J.C., and Miller, J.D. Yield comparisons between sugarcane plantings of tissue culture derived and heat-treated seedcane and comparisons between virus-free and sugarcane yellow leaf virus infected sugarcane. 2003. Sugar Journal 66:23. Comstock, J.C., and Miller, J.D. Reliability of leaf-midrib tissue blot immunoassay to detect sugarcane yellow leaf virus and differences between cultivars in rate of spread. 2003. International Society of Sugar Cane Technologists Seventh Sugarcane Pathology Workshop abstracts. Page 1.

Impacts
(N/A)

Publications

  • Comstock, J. C., Miller, J. D. Incidence and spread of sugarcane yellow leaf virus in sugarcane clones in the CP-cultivar development program at Canal Point. J. Amer. Soc. Sugar Cane Technologists 2003. v. 23. p.71- 78.