Location: Sugarcane Field StationTitle: Sugarcane Genotype Selection for Sand Soils in Florida) Author
|Del Blanco, Isabel|
Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/1/2009
Publication Date: 11/1/2009
Citation: Glaz, B.S., Irey, M., Hu, C., El-Hout, N., Langdale, J., Del Blanco, I.A. 2009. Sugarcane Genotype Selection for Sand Soils in Florida. American Society of Agronomy Abstracts.59-6. Interpretive Summary: The cooperative sugarcane breeding program located at Canal Point, FL has been responsible for substantial yield gains for Florida growers with organic (muck) soils. However, during the past three decades, this breeding program was not responsible for yield improvement for sand soils. Thirty-one sugarcane varieties were planted on a sand soil in 2007. These varieties were grown with and without added mill mud. Mill mud is an organic waste produced from the clarification of sugarcane juice, and it is rich in N, P, K, Ca, and Mg. Also, in Florida, mill mud is largely muck soil that passes through the mill with the sugarcane. Yields of the thirty-one sugarcane varieties were compared on sand and sand with mill mud with the hope that the sand with mill mud would be indicative of variety performance on Florida’s muck soils. Relative yields of 25 of the varieties were similar on both soil treatments, but differed due to soil treatment for six varieties. Three varieties, CL 90-4725, CP 00-1446, and CP 01-1372 would not have been identified as high yielding varieties based on their performance on the sand soil, but were outstanding with the added mill mud. In previous research, all three of these varieties had high yields on sand soils. One new variety, CPCL 01-0877, also expected to yield well on sand soils based on previous research, had high yields on the sand, but not on the mill mud. CP 01-2390 had high yields on the mill mud and extremely high yields on sand; and CP 78-1628 had mediocre yields on sand and poor yields on mill mud. The early stages of the Canal Point program are conducted entirely on muck soils. Scientists and growers are interested in determining if conducting early selection stages on sand soils will improve the program’s ability to identify high-yielding varieties for sand soils. The results of this study suggest that conducting early-stage selection on sand soils would be more detrimental than current practices because more high-yielding varieties (three) would have been lost (compared to those gained (one).
Technical Abstract: There have been excellent, long-term results in identifying high yielding sugarcane (Saccharum spp.) varieties for organic (muck) soils in Florida. However, newer varieties for sand soils in Florida have not had yield improvements during a recent 33-year period. The purpose of this study was to compare the performance of 31 sugarcane varieties on sand soils with and without mill mud added at the rate of 1510 cubic meters per ha. A by-product from the sugarcane milling process, mill mud is an organic waste produced from the clarification of sugarcane juice, and it is rich in N, P, K, Ca, and Mg. The experiment was planted with soil treatment as main plots and varieties as subplots on a Margate sand soil in 2007. Commercial recoverable sucrose (CRS) (g sucrose per kg cane), cane yield (Mg per ha), and sucrose yield (Mg per ha) were determined about 1 year after planting. The mean CRS on sand soil was much higher than with added mill mud (116 vs. 136 g sucrose per kg cane). However, yields of cane and sucrose per hectare were much higher as a result of the added mill mud (216 vs. 103 Mg cane per ha, and 25 vs. 14 Mg sucrose per ha). Cane and sucrose yields of six varieties were differentially affected by whether or not mill mud was added to the sand (P = 0.10). CL 90-4725, CP 00-1446, and CP 01-1372 had high yields with mill mud, but mediocre yields on sand. CP 01-2390 had high yields under both treatments, but it was the second-highest yielding variety in plots without mill mud. CP 78-1628, the most widely grown sugarcane variety on sand in Florida, had mediocre yields on sand and poor yields on mill mud. Its yields on both treatments were probably substantially reduced by heavy brown rust (Puccinia melanocephala) infestation. CPCL 01-0877 had high yields on sand and low yields with mill mud. Adding mill mud was necessary to confirm previous research that CL 90-4725, CP 00-1446, and CP 01-1372 are high yielding on sand soils. Conversely, mill mud detracted in the confirmation that CPCL 01-0877 is high yielding on sand soils. The results for CL 90-4725, CP 00-1446, and CP 01-1372 raise concerns about variability on sand soils because previous research indicated that all three of these varieties would yield well on the sand soil without added mill mud.