NOTES MANUFACTURING
T. E. Reagan
Entomology Department, Louisiana State University Baton Rouge, Louisiana, and
O. Sosa, Jr.
Sugarcane Field Station, Agricultural Research Service U.S. Department of Agriculture, Canal Point, Florida
The sugarcane delphacid, Perkinsiella saccharicida Kirkaldy, an exotic pest of sugarcane was discovered in Louisiana on October 19, 1994, in a sugarcane field approximately 58 km southeast of Lafayette, LA. Feeding by nymphs and adult oviposition cause some debilitation of the sugarcane plant, but of principal concern is its ability to vector Fiji disease. After initial discovery, the 20 sugarcane-producing parishes of Louisiana were surveyed during November 1994 to determine sugarcane delphacid field densities and geographic distribution. The sugarcane delphacid was found in 22 of the 60 fields sampled, and in 13 of 20 parishes surveyed. Counts of adults ranged from a low of zero to a high of 12 in a field surveyed in St. Mary Parish.
Nymphs were found only in 7 parishes and, in general, were found in those parishes with correspondingly high adult numbers. The results of a spring 1995 survey will also be included.
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Journal American Society of Sugar Cane Technologists, Vol. 16, 1996
The West Indian Cane Weevil, a New Pest of Sugarcane in Florida
Omelio Sosa, Jr.
Sugarcane Field Station, USDA-ARS Canal Point, Florida James M. Shine, Jr.
Florida Sugar Cane League Clewiston, Florida
P. Y. P. Tai
Sugarcane Field Station, USDA-ARS Canal Point, Florida
The West Indian cane weevil (WICW), Metamasius hemipterus (L), was detected for the first time in the U.S. in Homestead, Florida in 1984. In September 1994, a heavy infestation of this weevil was observed on sugarcane cultivar CP 85-1382. This cultivar was released to growers in 1993 and its acreage is very small. All known locations of this cultivar were surveyed, and the weevil was found on 11 of 18 locations surveyed. One location had 32% of the stalks infested, and another had 21%. Damage is confined to the lower internodes. The inside of the stalks are hollowed out, causing stalks to lodge. Infested stalks (170) were split open, all stages of growth of the WICW were present, and their number/stalk ranged from 0-13, with a mean of 2.4 weevils, 86% were larvae. Glucose and fructose were higher, and sucrose was lower in infested cane than in non-infested cane. Stalk weight of infested cane was significantly lower than non-infested cane. A replicated test of 10 commercial sugarcane cultivars was evaluated for resistance/susceptibility to the weevil. Infestation ranged from 0-14% of the stalks infested, with CP 85-1382 being the most susceptible, followed by CP 80-1743 (12%); 4%
was the mean over all cultivars. Since there is no known biological control organism, and insecticidal control does not look promising, plant resistance could offer the best control approach against this pest.
Evaluation of Parental Clones in Breeding for Ratoon Stunting Disease Resistance J.D. Miller, J.C. Comstock, and P.Y.P. Tai
USDA-ARS Sugarcane Field Station Canal Point, Florida
Clones selected for advancement in the Canal Point Cooperative Sugarcane Breeding Program have been inoculated with Ratoon Stunting Disease (RSD) in separate tests for the past three years. Size of plots and the number of replications vary according to selection stage (amount of seedcane available). The number of stalks sampled per clone varied from three (3) to twenty (20). Since these are preliminary RSD ratings, only the susceptible clones, which showed colonized vascular bundles (CVB) were discarded. Seven female parents (CP 70-1133;
CP 89-2149; CP 84-1322; CP 85-1025; CP 89-2319; US 90-1025 and Co 285) in the CP 92 &
95 series with at least 10 progenies had no progeny discarded. There were six female parents (CP 76-1306; CP 86-1427; CP 86-1670; CP 87-1733, CP 85-1758, and US 88-1014) that had
>20% of their progeny discarded and CP 76-1306 and CP 87-1733 had >40% of their progeny discarded. All male parents with >10 progeny had at least one clone discard for susceptibility.
Journal .American Society of Sugar Cane Technologists, Vol. 16, 1996
1143, Akoki 22, CP 85-1491, CP 88-2045, and CP 89-2178) had >20% of their progeny discarded for RSD susceptibility. The average number of CVB for male parents with >10 progeny ranged from 1.81 for CP 81-1238 to a high of 6.31 for CP 88-2045. For the female parents, the average number of CVB ranged from 1.05 for US 90-1025 to 7.84 for US 88-1014.
We feel that these data, although preliminary, show evidence that we should be able to effectively breed for resistance to RSD.
Relationship Between Ratoon Stunting Disease Resistance and Disease Incidence of Sugarcane Cultivars in Commercial Fields.
J. C. Comstock Sugarcane Field Station, USDA-ARS
Canal Point, Florida R. Perdomo and J. Powell Okeelanta Sugar Corporation
South Bay, Florida
The purpose of this study was to determine ratoon stunting disease (RSD) ratings of sugarcane cultivars based on the number of colonized vascular bundles (CVB) and correlate to disease incidence. RSD resistance ratings were determined by determining the number of CVB of cultivars in commercial sugarcane fields surveyed that were planted with seedcane that had no history of heat treatment or phytosanitary practices to control RSD. Field incidence of RSD stalk infection correlated (r =0.87) to the number of CVB in 220 commercial fields surveyed. Resistant cultivars, CL 73-239 and CP 72-2086, that had averaged 0.03 and 0.15 CVB, respectively, had an average of 2.7 and 1.4% stalks infected in 9 and 28 commercial fields surveyed. In contrast, susceptible cultivars, CL 61-620 and CP 72-1210, that had averaged 11.8 and 7.6 CVB, respectively, averaged 99.2 and 92.7% stalk infection in 38 and 8 fields surveyed. The results indicate that RSD did not increase in resistant cultivars in Florida even though no heat treatments and phytosanitary practices were conducted.
Selection for Cold Tolerance in Sugarcane P. Y. P. Tai and J. D. Miller USDA-ARS Sugarcane Field Station
Canal Point, Florida
Improvement of cold tolerance for sugarcane would sustain stable productivity of this crop in cooler regions and prevent loss in the Everglades Agricultural Area following serious freezes.
The breeding of sugarcane cultivars resistant to cold injury has been one of the major objectives of the work of the United States Department of Agriculture at Canal Point, Florida. Sugarcanes in both Florida and Louisiana are grown in relatively high latitude regions where temperatures periodically drop below freezing and can cause a serious damage to sugarcane crop. Cold injury can cause significant reduction in growth of young cane and deterioration in juice quality.
Sugarcane cold tolerance may be divided into three categories: (1) the resistance of leaves and buds to frost injury under relatively light freeze temperatures (0 to -3.3°C); (2) the resistance of stalk to freezing and subsequent deterioration under moderate freeze temperatures (-3.9 to - 5.6°C); and (3) the ability to restubble after severe winters (below -5.6°C). Categories 1 and 2 are more important than category 3 to the sugarcane production in Florida.
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Journal American Society of Sugar Cane Technologists, Vol. 16, 1996
A group of selected clones derived from backcrosses of hybrids between commercial cane and Saccaharum spontaneum was used to evaluate their responses to low temperature stress under field conditions. The experiment was carried out at the University of Florida Institute of Food and Agricultural Sciences Agronomy Farm, Gainesville from 1992 to 1994. Measurements of cold tolerance were based on the estimates of the green leaf area after freezes. Stalk samples also were taken to measure fiber content and juice quality for determining their possible association with cold tolerance. The frequency distribution of cold tolerance ratings appeared to be normal among selected clones under relatively light freezes, but the frequency distribution was skewed toward higher cold tolerance rating. Resistance to cold injury was positively associated with percentage of fiber content under moderate freezes but not under light freezes. A significant interaction between clones and environments suggested that selection for cold tolerance has to be based on tests at several locations and/or for several years. Statistical evaluation of response of sugarcane to low temperature stress should improve the effectiveness of selection for cold tolerance in sugarcane. The difficulty of gene transfer from S. spontaneum to sugaracne during nobilization is well known. It appears that there is no exception for cold-tolerant genes.
Recurrent selection for cold tolerance by using combined gene pools of S. spontaneum plus hardier commercial cultivars may be more effective strategy to prevent loss of cold tolerance genes in the course of backcrosses or nobilization. Also induction of chromosome breakage with physical and chemical mutagens to increase recombination in early backcross generations or nobilization should be explored.
TCP 87-3388, a New, Early Sugarcane Variety for Texas J. E. Irvine
Texas A&M AREC Center, Weslaco, Texas J. D. Miller
USDA-ARS Sugarcane Field Station, Canal Point, FL B. L. Legend re
USDA-ARS Sugarcane Research Unit, Houma, LA
The sugarcane variety TCP 87-3388 is from a polycross with CP 70-321 made in Canal Point, FL, in 1982. The seed was germinated in 1983 at Houma, LA, followed by two years of selection there. It was brought to Texas in 1985. The outstanding characteristic of TCP 87-3388 is its early maturity; it is the most precocious variety tested that has commercial value. On its earliest harvest date (September 13th) it produced a theoretical recoverable sugar yield of 10.4%
sugar per ton of cane. If sustained, this level of sugar would permit Texas to harvest ten days earlier than its earliest date (Sep. 22, 1993). Early sampling showed that sugar per ton of TCP 87- 3388 is superior or equal to CP 70-321 and superior to NCo 310. These latter two varieties occupy 85% of the Texas cane area. Its ash content is low and fiber is normal. TCP 87-3388 appears to be more resistant to the cane borer (Diatraea saccharalis F.) and the rice borer (Eoreuma loftini Dyar) than NCo 310 and less resistant than CP 70-321. Test plots surveys show that TCP 87-3388 is resistant to sorghum mosaic (SCMV-H), sugarcane smut {Ustilago scitaminea Sydow), and sugarcane rust (Puccinia melanocephala H. Syd. and P. Syd.) under Texas conditions. TCP 87-3388 can be infected by ratoon stunting disease {Clavibacter xyli xyli Davis et al), but its reaction is unknown and heat treatment of seed cane is recommended. TCP 87-3388 occasionally shows symptoms of yellow leaf syndrome, a disorder of unknown etiology.
Journal American Society of Sugar Cane Technologists, Vol. 16. 1996
Engineering Sugarcane for Resistance to Sugarcane Mosaic Virus T. E. Mirkov
Dept. of Plant Pathology and Microbiology Texas A&M Agricultural Experiment Station, Weslaco, TX