Sugarcane cultivar response to glyphosate and trinexapac-ethyl ripeners in Louisiana

Abstract

Sugarcane ripening in Louisiana is necessary to ensure adequate sucrose levels in early-season harvested sugarcane. The response of nine sugarcane cultivar’s yield components to glyphosate and trinexapac-ethyl ripeners was determined in field trials. Glyphosate (210 g ae ha -1 ) and trinexapac-ethyl (200 g ai ha -1 ) treatments failed to increase sucrose yields more than non-ripened sugarcane. Sugarcane ripened with glyphosate or trinexapac-ethyl increased theoretical recoverable sucrose (TRS) 4 to 12% more than non-ripened sugarcane in seven out of nine cultivars, but greater TRS values were counterpoised by lower sugarcane stalk weight. An unintentional consequence of reduced late-season vegetative growth may benefit growers by allowing them to harvest more sugarcane hectares to meet their daily load quota and exposes fewer hectares to a freeze event. The cultivars HoCP 00–950, Ho 09–804, and HoCP 09–840 were not responsive to glyphosate or trinexapac-ethyl ripeners and should not be treated. A delayed harvest from 28 to 49 days after treatment (DAT) coincided with greater TRS values and 17% more sucrose yield.

Enhanced Activity of Genes Associated With Photosynthesis, Phytohormone Metabolism and Cell Wall Synthesis Is Involved in Gibberellin-Mediated Sugarcane Internode Growth

“…Sugarcane is a major agricultural crop in China, which as a country provides ∼80% of sugar produced globally (Chen et al, 2019), the second largest bioenergy crop in the world (Tomes et al, 2011). Sucrose is stored in the sugarcane stem and shoot height is an important determinant of sugar yield (Spaunhorst et al, 2019). Shoot length in graminaceous plants is largely determined by internode elongation, which is controlled the genetic make-up (Qi et al, 2011;Li et al, 2012), environmental factors (Mazzella et al, 2000;Peralta et al, 2002), and hormonal interactions (Buck-Sorlin et al, 2005;Liu et al, 2016).…”

Registration of ‘Ho 07‐613’ sugarcane

“…On years where conditions favor natural ripening of sugarcane, there is frequently little or no response of sugarcane to ripener application. In a similar study, Spaunhorst et al (2019) reported an increase in TRS of 9% in glyphosate-treated Ho 07-613 over the nontreated control.…”

Registration of ‘Ho 05‐961’ sugarcane

“…The sucrose concentrations for cultivars L 01-299 and HoCP 96-540, the two most planted sugarcane cultivars in Louisiana, were among the most responsive (11-17% increase) and are considered highly responsive to glyphosate (Orgeron et al, 2019;Spaunhorst et al, 2019). Unfortunately, some cultivars treated with glyphosate ripener are shorter, and a reduction in sugarcane biomass may result from a glyphosate application (Spaunhorst et al, 2019). Orgeron et al (2019) reported that HoCP 00-950 responded moderately to glyphosate ripener.…”