Genetic variation and advance for rind hardness, flowering and sugar yield traits in sugarcane

Abstract

In sugarcane ( Saccharum spp.), rind hardness is an important factor in reducing sugarcane borer ( Diatraea saccharalis (F.)) damage. Many methods of measuring ring hardness have been used in sugarcane. However, the portable maize ( Zea mays L.) rind penetrometer has not been evaluated. The objective of this research were to determined broad-sense heritability, genetic variation, and genetic advance for several agronomic traits including rind hardness in sugarcane. A control and 47 randomly selected clones were planted in 1983 and 1984 at two locations in Florida. Data were obtained on stalk number, stalk weight, sugar concentration, cane yield and sugar yield, juice extraction, fiber content, rind hardness (measured in pressure required to push a penetrometer needle through the rind), and flowering in plant cane and ratoon crops. For each trait, broad-sense heritability, coefficient of genetic variation and expected genetic advance at 10% selection intensity were determined. Heritability estimates were high for stalk weight (88%), rind hardness (88%), fiber content (86%), flowering (85%), fiber-cake moisture (78%), and stalk number (67%); and lower for sugar concentration (43%), juice extraction (43), cane yield (49%), and sugar yield (49%). Coefficient of genetic variation was highest for flowering (43%) and lowest for juice extraction (3%). The genetic advance values (% of mean) were 19% for sugar yield, 20% for stalk number, 27% for stalk weight, 24% for rind hardness, 15% each for cane yield and fiber content, 5% for sugar concentration, and 3% for juice extraction. We concluded that the maize rind-penetrometer method would be a useful device for differentiating rind hardness in sugarcane for screening for this character.