Sugarcane Pathology Research - LOUISIANA STATE UNIVERSITY

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
212	2020	1160	100%

Progress 09/30/00 to 08/31/05

Outputs
Research results were obtained pertaining to all project objectives. Experimental clones in the cultivar selection program were evaluated annually for resistance to smut, leaf scald, rust and mosaic. Three disease resistant culitvars, Ho 95-988, HoCP 96-540, and L 97-128, were released. Basic germplasm was screened, and new potential sources of resistance to red rot were identified. Studies on the inheritance of resistance to red rot were initiated. An annual experiment to evaluate tolerance to billet planting was initiated. Additional research addressed the effects of fungicides, antitranspirant coatings, harvester settings, and date and rate of planting on billet planting performance. Fungicides and antitranspirants did not reduce red rot severity and increase yields. Harvester settings to minimize physical billet damage were identified. Very early or late planting dates and low billet planting rates resulted in reduced yields. The economics of whole stalk and billet planting were evaluated, and the costs of billet planting were found to be higher. Widespread planting of a cultivar with resistance to the spread of ratoon stunting disease (RSD) and planting of certified healthy seedcane resulted in effective control of RSD. Healthy plant material was provided annually through a local quarantine to commercial companies for tissue-culture seedcane production, and RSD was monitored in seedcane fields, the cultivar selection and increase programs, and commercial fields. RSD spread was greater with the whole stalk harvester compared to the chopper harvester, and cultivars were found to vary in the rate of RSD spread. The rate of RSD spread and extent of colonization by the pathogen were correlated among cultivars. The geographic distribution, incidence, epidemiology, and effect on yield of sugarcane yellow leaf virus (SCYLV) were determined. The effect on yield was dependent upon cultivar. Despite widespread distribution, high rates of disease increase were not detected. The highest rate of increase coincided with the spring aphid migration. Virus spatial distribution within fields was mainly random suggesting little secondary spread. The results suggest yellow leaf can be controlled with a healthy seedcane program, and virus testing was added to the seedcane certification program. Changes were detected in the rhizosphere prokaryotic community associated with sugarcane monoculture. Protoporphyrinogen oxidase inhibitor herbicides were found to inhibit the growth of Pythium species and affect root colonization. They also affected the functional diversity of the soil microbial community. Brown rust was demonstrated to reduce yield, and studies to determine the efficacy of fungicides were initiated.

Impacts
The continuous development of disease resistant cultivars is essential. Brown rust is currently a problem, and three new cultivars should have a positive effect on this situation. The frequency of resistance to red rot is low in the current parent and cultivar selection populations. The identification of new sources of resistance and information on the inheritance of resistance should lead to the development of red rot resistant cultivars. Billet harvesting has become predominant in Louisiana, so methods for successful billet planting are needed. Practices to maximize success in billet planting were identified, although whole stalk planting remains the superior system. The availability of cultivars resistant to ratoon stunting disease spread, the availability of certified, healthy planting material, and disease monitoring have reduced the incidence of what was the most important disease for many years to less than 1%. Research on the epidemiology of yellow leaf suggested that it may be possible to prevent this disease from having a major impact by utilizing a healthy seedcane program. Yellow leaf was added to the seedcane certification standards, and seedcane source testing has been performed for two years. Improved understanding of detrimental changes in soil microbial communities associated with sugarcane monoculture and evaluation of alternative control measures could lead to reductions in losses due to soilborne disease. Integrated management practices are available to farmers that allow them to minimize losses to most sugarcane diseases.

Publications

Daugrois, J.H., Hoy, J.W., and Griffin, J.L. 2005. Protoporphyrinogen oxidase inhibitor herbicide effects on Pythium root rot of sugarcane, Pythium species, and the soil microbial community. Phytopathology 95:220-226.
Hoy, J. 2005. Healthier sugarcane thanks to tissue culture. Sugar J. 67(9):6.
Hoy, J. 2005. Healthy seedcane: It's still important. Sugar Bull. 83(12):8-9.
Hoy, J. 2002. Are diseases a threat to 384? Sugar Bull. 80(7):17-18.
Hoy, J., and Legendre, B. 2002. An assessment of plant cane stand problems during Spring, 2002. Sugar Bull. 80(10):25-26.
Hoy, J., and Legendre, B. 2003. Observations on plant cane stands during Spring, 2003. Sugar Bull. 81(10):33.
Hoy, J., Arceneaux, A., and Savario, C. 2003. Billet planting research results from 2002. Sugar Bull. 81(10):34-36.
Hoy, J., Grelen, L., and Paccamonti, J. 2001. Don't miss this great opportunity. Sugar Bull. 79(12):17-19.
Hoy, J., Grelen, L., and Paccamonti, J. 2002. Can you afford to ignore RSD? Sugar Bull. 80(1):21-22.
Hoy, J., Grelen, L., and Paccamonti, J. 2003. RSD and the canary in the coal mine. Sugar Bull. 81(12):21-22.
Hoy, J., Grelen, L., and Paccamonti, J. 2004. RSD testing time again. Sugar Bull. 83(1):19-20.
Hoy, J.W. 2001. Controlling disease. Louisiana Agric. 44(4):10-11.
Hoy, J.W. 2001. Planting sugarcane: Whole stalks versus billets. Louisiana Agric. 44(4):7-9.
Hoy, J.W., Arceneaux, A.E., Savario, C.F., Jackson, W.R., and Waguespack, H.L., Jr. 2002. Billet planting research results from 2001. Sugar Bull. 80(10):19-24.
Hoy, J.W., Arceneaux, A.E., Savario, C.F., Richard, C.A., Jackson, W.R., and Waguespack, H.L., Jr. 2001. Billet planting research results from 2000. Sugar Bull. 79(10):11-15.
Hoy, J.W., and Flynn, J.L. 2001. Control of ratoon stunting disease of sugarcane in Louisiana with seedcane produced through micropropagation and resistant cultivars. Proc. Int. Soc. Sugar Cane Technol. 24:417-421.
Hoy, J.W., Bischoff, K.P., Milligan, S.B., and Gravois, K.A. 2003. Effect of tissue culture explant source on sugarcane yield components. Euphytica 129:237-240.
Hoy, J.W., Richard, C.A., Jackson, W.R., and Waguespack, H.L., Jr. 2004. Effects of cultivars, fungicides, and fertilization at planting on yields obtained from whole stalk and billet plantings in Louisiana. J. Amer. Soc. Sugar Cane Technol. 24:70-80.
Lopes, S., Damann, K.E., Hoy, J.W., and Grisham, M.P. 2001. Infectivity titration for assessing resistance to leaf scald among sugarcane cultivars. Plant Dis. 85:592-596.
Martin, F.A., and Hoy, J.W. 2001. Sugarcane: An important commodity facing many challenges. Louisiana Agric. 44(4):6.
McAllister, C., Hoy, J., and Reagan, G. 2003. Yellow leaf virus in Louisiana sugarcane. Sugar Bull. 81(11):28-29.
McAllister, C.D., Hoy, J.W., and Reagan, T.E. 2005. Temporal increase of yellow leaf of sugarcane in Louisiana. Proc. Int. Soc. Sugar Cane Technol. 25(2):711-714.
Salassi, M., and Hoy, J. 2003. Estimated cost of whole stalk and billet planting methods. Sugar Bull. 81(11):32-35.
Salassi, M.E., Breaux, J.B., and Hoy, J.W. 2004. Estimated cost differences between whole stalk and billet sugarcane planting methods in Louisiana. J. Amer. Soc. Sugar Cane Technol. 24:250-257.

Progress 01/01/04 to 12/31/04

Outputs
Two sugarcane cultivars, Ho 95-988 and L 97-128, were released during 2004. These cultivars have good to acceptable resistance to the diseases of importance and will provide an alternative to the current number one cultivar, LCP 85-384, that is susceptible to rust. Screening in the selection program identified clones with resistance to smut, leaf scald, and mosaic. A seedling inoculated test showed promise for evaluation of heritability of resistance to leaf scald. Research to develop methods for successful planting of stalk billets continued. Results were obtained from first and second ratoon crops of experiments evaluating planting date and rate of planting. Very early and late planting dates have produced lower yields. Low planting rates also have produced lower yields, while very high rates have not increased yield. Ratoon stunting disease testing contributed to an on-going survey of infection levels in the Louisiana sugarcane industry. The incidence of farms, fields, and stalks per field were 14.3, 6.7, and 1.2%, respectively. Factors associated with decreased RSD were widespread cultivation of a cultivar with resistance to disease spread, LCP 85-384, and planting of healthy seedcane produced through micropropagation and certification by the La. Dept. of Agriculture and Forestry. RSD was not detected in sources of commercial micropropagated seedcane. A local quarantine was conducted to provide healthy plant material to establish foundation stock plants that provide the source for micropropagation. A four year study comparing the rate of RSD spread by chopper and whole stalk harvesters and in different cultivars was completed. The chopper harvester did not spread RSD more rapidly than the whole stalk harvester. Differences were detected among cultivars in rate of RSD spread. Spatial distribution of Sugarcane yellow leaf virus (SCYLV) infection and aphid vectors was analyzed with data from contiguous quadrat plots in four fields over two seasons. Initial distributions were random, and patterns remained random with occasional aggregation detected. Certification of commercial seedcane for SCYLV infection was conducted for the first time. A decrease in yield was detected in infected LCP 85-384 in second ratoon. Virus infection did not decrease yield of Ho 95-988 in plant cane. The effect of rust on yield in Louisiana was determined for the first time. Cane tonnage increased 21% when rust was controlled by multiple fungicide applications at one location. Rhizosphere soil samples were collected from adjacent fields with and without a recent sugarcane cropping history, and the prokaryotic communities were different when compared with sole carbon source utilization profiles.

Impacts
Continued development of disease resistant cultivars is essential. Two new cultivars should have a positive impact. Billet harvesting has become predominant in Louisiana; therefore, developing methods for successful billet planting is imperative. Practices have been identified that will maximize the chances of success. Historically, ratoon stunting disease, RSD, has been the most important disease in Louisiana. Significant yield losses will not result from the disease levels now occurring. The reductions in RSD result from a partnership between the LSU Agricultural Center, the La. Dept. of Agriculture and Forestry, and a commercial seedcane company that makes certified, healthy seedcane available and by the cooperative breeding program that produced the widely planted, RSD resistant cultivar, LCP 85-384. Availability of certified seedcane produced through micropropagation also contributes to the management of other systemic diseases, including mosaic, smut, leaf scald, and yellow leaf. Research on spread and increase of Sugarcane yellow leaf virus suggests it can be managed by a healthy seedcane program utilizing micropropagated seedcane, and this disease was added to the seedcane certification standards for 2004. Demonstration of the impact of rust on LCP 85-384 will speed the shift to new culivars. Improving understanding of detrimental changes in soil microbial communities associated with sugarcane monoculture and evaluation of alternative control measures could lead to reductions in losses due to soilborne disease.

Publications

Hoy, J., Grelen, L., and Paccamonti, J. 2004. RSD testing time again. Sugar Bull. 83(1):19-20.
Hoy, J. W., Richard, C. A., Jackson, W. R., Waguespack, H. L., Jr. 2004. Effects of cultivars, fungicides, and fertilization at planting on yields obtained from whole stalk and billet planting in Louisiana. J. Amer. Soc. Sugar Cane Technol. 24:70-80.
Salassi, M. E., Breaux, J. B., and Hoy, J. W. 2004. Estimated cost differences between whole stalk and billet sugarcane planting methods in Louisiana. J. Amer. Soc. Sugar Cane Technol. 24:250-257.

Progress 01/01/03 to 12/31/03

Outputs
Screening in the cultivar selection program identified clones with resistance to smut, leaf scald and mosaic. HoCP 96-540, a cultivar with resistance to all the major diseases in Louisiana, was released during 2003. Research to develop methods to plant billets continued. Yields varied in the plant cane year of a date of planting experiment. Yield was lower for a late season, mid-October, date. In two prior experiments, yield differences in plant cane were no longer evident in the ratoon crops. In three rate of planting experiments, yields have been consistently lower at low rates (one or three running billets) in plant cane, and the reduction has been more pronounced for a mid-September compared to mid-August planting date. The highest rate of planting, 12 running billets, has not provided increased yield. The costs of billet and whole stalk planting were compared. Due to increased seedcane use and unrealized income due to that use, billet planting is more expensive than whole stalk planting at current planting rates for each method. Ratoon stunting disease (RSD) testing contributed to an on-going survey of infection levels in the Louisiana sugarcane industry. The incidence of fields with RSD was 9% during 2003, and the incidence of stalk infection was 1%. Factors associated with decreased RSD were widespread cultivation of a cultivar with resistance to disease spread, LCP 85-384, and planting of healthy seedcane produced through micropropagation and certification by the La. Dept. of Agriculture and Forestry. However, RSD incidence considered on a farm basis was 32%, indicating that RSD is persisting at low levels in the industry. RSD was not detected in sources of commercial micropropagated seedcane. A local quarantine was conducted to provide healthy plant material for foundation plants that provide the source for micropropagation of seedcane. Differences were detected among clones in the third season of a RSD spread experiment. Rates of spread caused by whole stalk and billet harvesters were similar. In a follow-up of a 2002 state-wide survey for Sugarcane yellow leaf virus, 17 fields were re-sampled and assayed for SCYLV. None of eight fields with no virus detected in 2002 had become infected, and the disease only increased in five of nine previously diseased fields. Disease incidence increased by an average multiple of 0.45. The average infection level within diseased fields was 10% during 2003. Yellow leaf spread and increase experiments were conducted for a second year. Monitoring of aphid vector populations and virus incidence over time suggested that virus infections increase at the greatest rate at the time of the first influx of aphids during the spring migration. Virus infection continues to increase but at a lower rate as aphids colonize the sugarcane during summer. SCYLV infection did not result in decreased yield of LCP 85-384 in an experiment in second ratoon or in a second experiment in plant cane. Bacteria isolated from rhizosphere soil associated with roots of sugarcane plants growing in soils with and without a recent sugarcane cropping history were identified by sole carbon source utilization profiles.

Impacts
The continued development of disease resistant cultivars for the Louisiana sugarcane industry is essential. Billet harvesting has become predominant in Louisiana; therefore, developing methods for successful billet planting is imperative. Practices have been identified that will maximize the chances of success in billet planting. Historically, ratoon stunting disease, RSD, has been the most important sugarcane disease in Louisiana. Significant yield losses will not result from the disease levels now occurring in the industry. The reductions in RSD are the result of a partnership between the Louisiana State University Agricultural Center, the Louisiana Department of Agriculture and Forestry, and a commercial seedcane company that makes certified, healthy seedcane available and by the cooperative breeding program that produced the widely planted, RSD resistant cultivar, LCP 85-384. The availability of certified seedcane produced through micropropagation also contributes to the management of other systemic diseases, including mosaic, smut, leaf scald, and yellow leaf. The research on spread and increase of Sugarcane yellow leaf virus suggests that the yellow leaf can be managed by a healthy seedcane program utilizing micropropagated seedcane, and this disease was added to the seedcane certification standards for 2004. Improving our understanding of detrimental changes in soil microbial communities associated with sugarcane monoculture and evaluation of alternative control measures could lead to reductions in losses due to soilborne disease.

Publications

Salassi, M. and Hoy, J. 2003. Estimated cost of wholestalk and billet planting methods. Sugar Bull. 81(11):32-35.
Hoy, J., Arceneaux, A. and Savario, C. 2003. Billet planting research results from 2002. Sugar Bull. 81(10):34-36.
Hoy, J., Grelen, L. and Paccamonti, J. 2003. RSD and the canary in the coal mine. Sugar Bull. 81(12):21-22.
Hoy, J. and Legendre, B. 2003. Observations on plant cane stands during Spring, 2003. Sugar Bull. 81(10):33.
Hoy, J.W., Bischoff, K.P., Milligan, S.B. and Gravois, K.A. 2003. Effect of tissue culture explant source on sugarcane yield components. Euphytica 129:237-240.
Hoy, J.W., Arceneaux, A.E. and Savario, C.F. 2003. Billet planting research. Pages 115-117, in: Sugarcane Research Annual Progress Report 2002. La. State Univ. Agric. Center Publ.
Hoy, J.W., Grelen, L.B., Savario, C.F., Paccamonti, J.Q. and McAllister, C.D. 2003. Pathology research. Pages 105-109, in: Sugarcane Research Annual Progress 2002. La. State Univ. Agric. Center Publ.
McAllister, C., Hoy, J. and Reagan, G. 2003. Yellow leaf virus in Louisiana sugarcane. Sugar Bull. 81(11):28-29.

Progress 01/01/02 to 12/31/02

Outputs
Ratoon stunting disease (RSD) testing contributed to an on-going survey of infection levels in the Louisiana sugarcane industry. The incidence of fields with RSD decreased from 52% in 1997 to 5% in 2002, and the mean stalk infection level per field was 1%. Factors associated with decreasing RSD incidence were widespread cultivation of a resistant cultivar, LCP85-384, and planting of healthy seedcane produced through micropropagation and certification by the Louisiana Department of Agriculture and Forestry. However, RSD field incidence in a susceptible cultivar, HoCP91-555, was 22%, indicating that RSD is still present in the industry. RSD was not detected in sources of commercial micropropagated seedcane. A local quarantine was conducted to provide healthy plant material for foundation plants that provide the source for micropropagated seedcane. Differences in rate of mechanical spread of RSD were detected among cultivars. The rate of RSD spread was similar with billet and whole stalk harvesting. Research to develop methods to successfully plant stalk sections, or billets, was continued. Yields were similar with four planting dates; however, an early planting date was not included. Lower yields resulted from planting rates of one to three running billets, compared to six, nine or twelve billets. Differences were greater in late planted billets. Differences detected in plant cane were no longer evident in first ratoon of date and rate of billet planting experiments. Microbial communities in soils with and without a recent sugarcane cropping history were compared to study changes that take place during long-time cultivation of sugarcane. Differences in carbon substrate utilization profiles and culturable microorganisms were detected in soils with and without a recent sugarcane cropping history at three sites. Sugarcane yellow leaf virus (SCYLV) was detected in all sugarcane growing areas of Louisiana. Incidence of infection within fields varied from 0-63%. No virus was detected in 22 of 42 (52%) of the fields sampled. Micropropagated seedcane sources were monitored for SCYLV. Virus infection did not cause significant yield loss in LCP85-384 in first ratoon. The occurrence of aphids, rate of infection increase, and pattern of disease spread were determined in on-going experiments at multiple locations. Screening in the cultivar selection program identified sugarcane clones with resistance to smut, mosaic, and leaf scald.

Impacts
Historically, RSD has been the most important disease of sugarcane in Louisiana. Significant yield losses will not result from the disease levels now occurring in the industry. The reductions in RSD have been made possible by a partnership between a commercial seedcane company, the Louisiana State University Agricultural Center, and a state regulatory agency that makes healthy seedcane available and by the cooperative breeding program that produced the widely planted, resistant cultivar, LCP85-384. The availablity of certified seedcane produced through micropropagation also contributes to the management of other systemic diseases, such as mosaic, smut, and leaf scald. Billet harvesting has become predominant in Louisiana; therefore, developing methods for successful billet planting is imperative. Practices have been identified that will maximize the chances of success in billet planting. Developing an understanding of the factors affecting SCYLV spread and increase and the effect of the virus on yield will help determine the potential impact of yellow leaf on sugarcane production in Louisiana. Improving our understanding of detrimental changes in soil microbial communities associated with sugarcane monoculture and evaluation of alternative control measures could lead to reductions in losses due to soilborne disease. Finally, development of new, disease resistant cultivars is essential.

Publications

Hoy, J. 2002. Are diseases a threat to 384? Sugar Bull. 80(7):17-18.
Hoy, J.W., Arceneaux, A.E. and Savario, C.F. 2002. Billet planting research. Pages 139-146, in: Sugarcane Research Annual Progress Report 2001. La. State Univ. Agric. Center Publ.
Hoy, J.W., Arceneaux, A.E., Savario, C.F., Jackson, W.R. and Waguespack, H.L.Jr. 2002. Billet planting research results from 2001. Sugar Bull. 80(10):19-24.
Hoy, J. and Legendre, B. 2002. An assessment of plant cane stand problems during Spring, 2002. Sugar Bull. 80(10):25-26.
Hoy, J., Grelen, L. and Paccamonti, J. 2002. Can you afford to ignore RSD? Sugar Bull. 81(1):21-22.
Hoy, J.W., Grelen, L.B., Savario, C.F., Paccamonti, J.Q. and McAllister, C.D. 2002. Pathology research. Pages 130-135, in: Sugarcane Research Annual Progress Report 2001. La. State Univ. Agric. Center Publ.

Progress 01/01/01 to 12/31/01

Outputs
Ratoon stunting disease (RSD) testing provided an on-going survey of infection levels in the Louisiana sugarcane industry. The average stalk infection incidence per field decreased from 12% in 1997 to less than 1% in 2001, and the incidence of infected fields decreased from 52% to 7% in the same period. Factors associated with decreasing RSD levels are use of healthy seedcane produced through micropropagation and certified by the Louisiana Department of Agriculture and Forestry and the widespread planting of a cultivar, LCP 85-384, with resistance to RSD spread. The annual local quarantine was conducted to produce healthy plant material for foundation plants that provide the source for micropropagation of seedcane. Research to develop methods to allow successful planting of stalk sections, or billets, continued. All current experiments were conducted with sugarcane cultivar, LCP 85-384. Lower yields resulted from early season planting and planting rates of one to three running billets. Plant cane yields from two farm experiments were higher in whole stalk compared to billet plantings. Yields were similar in whole stalk and billet plantings in three farm experiments in ratoon crops. This has been a typical pattern for LCP 85-384, in which billet planting yields were lower in plant cane but not ratoon crops. Antitranspirants and fungicides alone and in combination were compared in a billet dip experiment, and no treatment improved spring stand compared to the non-treated control. Harvester modifications were identified that would increase the frequency of billets without physical damage. In research to characterize and compare microbial communities in soils with and without a recent history of sugarcane cultivation, differences in culturable organisms were detected between soils and methods were developed to amplify a fragment of the 16S prokaryotic ribosomal subunit gene suitable for cloning and sequencing. Protoporphyrinogen oxydase inhibitor herbicides were shown to inhibit mycelial growth rate of three Pythium species in vitro. No consistent effects on root rot severity and sugarcane growth were detected in greenhouse experiments. Sugarcane yellow leaf virus (SCYLV) was detected in some commercial seedcane fields, and seedcane was not sold from those fields. No significant yield loss due to SCYLV was detected in plant cane of LCP 85-384. Experiments were established to determine the pattern and rate of increase of SCYLV in commercial fields. Screening in the cultivar selection program identified sugarcane clones with resistance to smut, mosaic, and leaf scald.

Impacts
RSD has historically been the most important disease of sugarcane in Louisiana. The reduction of infection levels represents a major positive development for the industry. The reductions in RSD have been made possible by a partnership between a commercial seedcane company, Louisiana State University, and a state regulatory agency that makes quality healthy seedcane available and by the cooperative sugarcane breeding program that produced LCP 85-384. Billet harvesting has become prevalent, so developing methods for billet planting is imperative. Practices have been identified that will maximize the chances of success in billet planting. Soilborne disease has been shown previously to be important in Louisiana. Improving our understanding of the detrimental changes in soil microbial communities associated with sugarcane monoculture and evaluation of alternative control measures could lead to reductions in losses due to soilborne disease. The potential threat posed by sugarcane yellow leaf virus to the Louisiana sugarcane industry needs to be evaluated. Finally, development of new disease resistant cultivars is essential.

Publications

Hoy, J.W. 2001. Controlling disease. Louisiana Agric. 44(4):10-11.
Hoy, J.W. 2001. Planting sugarcane: Whole stalks versus billets. Louisiana Agric. 44(4):7-9.
Hoy, J.W., Arceneaux, A.E. and Savario, C.F. 2001. Billet planting research. Pages 124-128, in: Sugarcane Research Annual Progress Report 2000. La. State Univ. Agric. Center Publ.
Hoy, J.W., Arceneaux, A.E., Savario, C.F., Richard, C.A., Jackson, W.R. and Waguespack, H.L., Jr. 2001. Billet planting research results from 2000. Sugar Bull. 79(10):11-15.
Hoy, J.W., Bischoff, K.P. and Gravois, K.A. 2001. Tissue culture method effects on sugarcane yield components. Pages 100-102, in: Sugarcane Research Annual Progress Report 2000. La. State Univ. Agric. Center Publ.
Hoy, J.W. and Flynn, J.L. 2001. Control of ratoon stunting disease of sugarcane in Louisiana with seedcane produced through micropropagation and resistant cultivars. Proc. Int. Soc. Sugar Cane Technol. 24:417-421.
Hoy, J.W., Grelen, L.B. and Paccamonti, J.Q. 2001. Don't miss this great opportunity. Sugar Bull. 79(12):17-19.
Hoy, J.W., Grelen, L.B., Savario, C.F. and Paccamonti, J.Q. 2001. Pathology research. Pages 114-120, in: Sugarcane Research Annual Progress Report 2000. La. State Univ. Agric. Center Publ.
Lopes, S., Damann, K.E., Hoy, J.W. and Grisham, M.P. 2001. Infectivity titration for assessing resistance to leaf scald among sugarcane cultivars. Plant Dis. 85:592-596.
Martin, F.A. and Hoy, J.W. 2001. Sugarcane: An important industry facing many challenges. Louisiana Agric. 44(4):6.