Authors: Arinta R. Puspitasari
, SetyonoY. Tyasmoro
, Agung Nugroho
, Sri Winarsih
,
Ida Wenefrida
, and Herry S. Utomo |
Abstract: Sugarcane is an important commodity in the world used for sugar and bioenergy. Weather
phenomenon, such as La Nina, and prolonged rainy seasons have impacted the cane plant and
sucrose yield and in many cases delayed ripening. The effects of four flooding periods were
studied in a replicated factorial design using four sugarcane varieties. The growth of
aboveground root increased as the duration of flood extended. The largest aboveground root
weight was produced by variety PSJT 941 when exposed to 12 weeks of flood. Each variety
responded to the flood treatments slightly differently in an aerenchyma number and stomata
density. Both upper and lower leaf surface stomata density were slightly affected by flood. PSJT
941 maintained a similar upper-leaf-surface stomata density throughout the treatments, except
during the 6-week flood treatment. As the flood durations increased, the proline content in the
leaves increased. A dramatic increase in the proline production was found in variety BL reaching
25.8 UM, which was four times higher than the proline content in the non-flooded (control) at the
end of the 12-week flood period. Flood treatments significantly affected sugarcane yield. Variety
PSJT 941 appeared very sensitive to the flood treatments. With 3 weeks of flood treatment, its
sugarcane yield reduced by 38% (3.55 kg). The sucrose yield of PSJT 941 also reduced
immediately just after 3 weeks of treatment, then further declined to 0.16 and 0.19 kg after 9 and
12 weeks of flood treatments, respectively. Dramatic effects of flooding were also found in
variety BL. Significant reduction of sucrose yield occurred just after 3 weeks of flooding and
continued to drop as the flood periods prolonged. After 12 weeks of flooding, its sucrose yield
was 0.03 kg (92% reduction). Varieties used in this study demonstrated differences in their
capabilities to respond to flooding. Even though there were no obvious physiological and
morphological traits that could directly be used as selection tools to breed for more flood-tolerant varieties, the information obtained can be used to develop flood mitigation strategies for
sugarcane. |