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Sugarcane has been an integral part of the South Louisiana economy and culture for more than 210 years. When the Jesuit priests first brought sugarcane to Louisiana in 1751, little did they know that they were laying the foundation for an industry that now contributes $2 billion to the Louisiana economy. The industry could not be sustained, however, without the research of the LSU AgCenter.
Read about this year's annual field day on July 15 at the Sugar Research Station. Registration begins at 8 a.m.
In the past century, research advances in both production and processing have kept Louisiana’s sugar industry alive. In recent times of stagnant and decreasing sugar prices, increased production efficiencies – including new high-yielding varieties – and new processing technologies have helped the Louisiana sugar industry remain profitable. The focus of LSU AgCenter sugarcane research is to help maintain a competitive and viable sugar industry in Louisiana.
Sugarcane is a tropical crop trying to survive in Louisiana’s temperate climate. The ability to grow sugarcane in Louisiana and increase sugar yields to levels attained in the tropics has largely been the result of sugarcane breeding efforts. These efforts began in Louisiana in the early 1920s. The development of new varieties for Louisiana is a cooperative effort involving the LSU AgCenter's Sugar Research Station, U.S. Department of Agriculture’s Agricultural Research Service in Houma, La., and the American Sugar Cane League.
Breakthrough Variety
Soon after its introduction in 1993, LCP 85-384 became the predominant Louisiana sugarcane variety and reached a peak acreage of 91 percent of the sugarcane acres in the state in 2004. By commonly outproducing the former leading variety by 25 percent or more sugar per acre, LCP 85-384 significantly increased producers’ gross income. However, in recent years, the percentage of the state’s acreage planted to LCP 85-384 has diminished because of the susceptibility of the variety to common rust, a fungal disease of sugarcane, and because of decreased vigor.
In its day, LCP 85-384 revolutionized Louisiana’s sugar industry not only with higher yields than other varieties but also with the ability to provide additional annual cuttings of stalks, termed stubble crops (because the new crop of stalks develops from the stubble remaining after harvest). The typical rotation for Louisiana sugarcane has been to plant a crop in late summer for harvest the following fall or winter followed by two stubble crops in subsequent years. With LCP 85-384 and subsequent new varieties, farmers can obtain three to four stubble crops with a single planting. Each additional year of stubble saves the grower the expense of planting new cane and of leaving a field out of production for a whole year.
The heavy tonnage they produce causes new varieties to have a tendency to fall down (lodge). Because of this, a new combine harvesting system was introduced in Louisiana in the mid 1990s. Combine harvesting systems are better suited to varieties such as LCP 85-384 and its successors and have improved harvest efficiency in the state. In 2007, it is estimated that 75 percent of the state's sugarcane crop was harvested by combines.
New Varieties Show Promise
Now, new varieties are replacing LCP 85-384, which faces reduced yields and disease problems.
“With 46 percent of the state’s acreage in LCP 85-384 in 2007, and a taste of higher production from newer varieties, there’s a lot of anticipation as new varieties are quickly expanded,” said Kenneth Gravois, resident coordinator of the Sugar Research Station in St. Gabriel.
Plant breeders are concerned that dependence on a single variety (monoculture) for any crop could spell disaster, if that particular variety suffers from a major disease or insect infestation. Their challenge, however, is to develop new varieties as good as or better than older varieties.
The LSU AgCenter and the USDA-ARS Houma unit have released seven new sugarcane varieties since 2003. HoCP 96-540 was released in 2003; L 97-128 was released by the AgCenter in 2004 as well as the USDA release Ho 95-988; L 99-226 and L 99-233 were released by the AgCenter in 2006; HoCP 00-950 was released by the USDA in 2007. L 01-283 was released by the AgCenter in 2008. All were developed under a three-way agreement among the LSU AgCenter, USDA and the American Sugar Cane League.
HoCP 96-540 is a cross developed by matching LCP 85-384 with another sugarcane variety known as LCP 86-454. The new 540 variety gives farmers an even better-yielding option, Gravois said. Several years of tests have shown that HoCP 96-540 produced cane and sugar yields 5 percent to 10 percent higher than the popular LCP 85-384. The new variety will likely replace LCP 85-384 as the most popular sugarcane variety for 2008 and was grown on 32 percent of the state’s acreage in 2007.
Gravois said a strong point for L 97-128 is its early maturity. Research data indicate L 97-128 produces approximately 9 percent greater recoverable sugar than LCP 85-384 and produces 14 percent higher recoverable sugar per ton of cane when harvested in mid September. It is a good choice for early harvest. L 97-128 was grown on 12 percent of the state's acreage in 2007.
The first of the two new 2006 variety releases, L 99-226, outyielded LCP 85-384 in the yield of sugar per acre by approximately 33 percent in 12 years of comparative tests conducted before its release in 2006. This improvement is attributed primarily to its superior yield of tons cane per acre but also its improvement in the yield of recoverable sugar per ton of cane. For the first time since the release of HoCP 85-845, L 99-226 is considered resistant to the sugarcane borer. L 99-226 is also resistant to common rust and can be grown on all soil types. This new variety was widely planted in 2007.
The second of the 2006 releases, L 99-233, also outyielded LCP 85-384 in the yield of sugar per acre by approximately 18 percent in comparative tests. Besides a high yield of sugar per acre, this new variety possesses a high population of small stalks with medium maturity. It is known for its excellent stubbling ability and can be grown on all soil types. This new variety was the choice of many growers when planting their heavier clay soils.
HoCP 00-950, released in 2007, has excellent sugar per ton as its main strength along with good resistance to many of the common diseases. Seed cane of this newest variety was made available to growers through the American Sugar Cane League in 2007.
The newest variety, L 01-283, was released in 2008. It joins several other sugarcane varieties released in the past few years to replace LCP 85-384. The new variety has an erect growing habit. “The variety stands up well and stubbles well,” Gravois said. “It offers high yield with good disease resistance and good insect resistance.”
Energy Cane
Sugarcane is a popular feedstock for ethanol production in Brazil and many think that sugarcane can be a valuable energy source in an emerging biofuels market in the United States. Ethanol can be produced from the sucrose produced in sugarcane’s sweet stalks or it can be produced from the conversion of bagasse – the fibrous pulp remaining after sucrose is extracted from the stalks.
Obtaining energy from bagasse is nothing new to the Louisiana sugar industry. Bagasse is typically burned as a fuel source in boilers that produce steam, which is the main energy source for operating factory equipment used to produce of raw sugar. Some sugar factories produce excess steam to operate turbines that cogenerate electricity for the factory.
With these possibilities in mind, three high fiber sugarcane varieties were released in 2007. The LSU AgCenter, in cooperation with the USDA-ARS and the American Sugarcane League, released L 79-1002. The USDA-ARS, in cooperation with the LSU AgCenter and the American Sugar Cane League, released HoCP 91-552 and Ho 00-961.
Some of these early-generation hybrids can be used to produce clones with high fiber content along with vigorous growth, excellent stubbling ability, a more erect growth habit, better cold tolerance and high yields of biomass. Biomass includes soluble solids (sugars) and insoluble solids (fiber, which is composed of cellulose, hemicellulose, and lignin), components that can be converted to ethanol.
HoCP 91-552 and Ho 00-961 have fiber content about three to four percentage points higher than commercial sugarcane varieties along with comparable sucrose content. These varieties could serve a dual purpose as sources of both raw sugar and fiber.
Impact
- LCP 84-385 revolutionized the sugarcane business in Louisiana. It boosted yields and spun off economic development through production and sales of new sugarcane harvesting equipment.
- Experts expect new variety releases to continue to bolster the position of Louisiana as one of the premier sugar-producing states in the country. Sugarcane variety development is a partnership among the LSU AgCenter, the USDA’s Agricultural Research Service and the American Sugar Cane League, which is headquartered in Thibodaux.
- Sugarcane is grown in 24 parishes. Louisiana has 12 sugar mills, one syrup mill and two refineries. A third refinery is planned and scheduled to go on line in 2009.
- Louisiana produces about 16 percent of the total sugar grown in the United States. This includes both beet sugar and cane sugar.
The LSU AgCenter is one of 11 institutions of higher education in the Louisiana State University System. Headquartered in Baton Rouge, it provides educational services in every parish and conducts research that contributes to the economic development of the state. The LSU AgCenter does not grant degrees nor benefit from tuition increases. The LSU AgCenter plays an integral role in supporting agricultural industries, enhancing the environment, and improving the quality of life through its 4-H youth, family and community programs.
(This AgCenter Lead was updated on July 8, 2009, by Linda Benedict.)