The effects of cobalt on sugarcane growth and development in plant cane and two ratoon crops

Authors: DASILVA, DEISE - Non ARS Employee; Johnson, Richard; CRUSCIOL, CARLOS - Sao Paulo State University (UNESP)

Submitted to: Sugar Tech
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/8/2022
Publication Date: 3/4/2022
Citation: Dasilva, D.P., Johnson, R.M., Crusciol, C.A. 2022. The effects of cobalt on sugarcane growth and development in plant cane and two ratoon crops. Sugar Tech. 2022:1-12. https://doi.org/10.1007/s12355-022-01108-4.
DOI: https://doi.org/10.1007/s12355-022-01108-4

Interpretive Summary: A study was conducted to determine if foliar application of cobalt fertilizer could improve sugarcane yields in Louisiana. We applied cobalt at five different concentrations, including a control that did not receive cobalt, to plant-cane and two ratoon crops. A variety of parameters were measured to evaluate the effects of cobalt application, including, the number of leaves and tillers, stalk diameter, plant height, plant water status, chlorophyll content, cane yield, sugar yield, and sugar quality. The plant-cane results demonstrated that foliar application of cobalt at 29 and 59 g/ha increased plant water use (open stomates), the number of leaves and tillers and sugar yield. When cobalt was not applied to the first-ratoon crop, the effects on measured parameters were less pronounced, although positive effects on tillers were still observed. Results for the second-ratoon crop, showed positive benefits on plant water use, the number of leaves and tillers, stalk heights, stalk weight, stalk diameter and sugar yield. Higher rates of cobalt (85 and 116 g ha/ha) decreased all the growth parameters except the number of internodes and tillers during second ratoon crop. Results from this study demonstrated that foliar application of low levels of cobalt to sugarcane can increase sugarcane growth and yields. Further research is needed to optimize cobalt fertilization rates and to determine the effects of cobalt on plant hormone levels.

Technical Abstract: This study was conducted to identify the effect of cobalt (Co) in three successive crops of sugarcane grown in Louisiana, U.S.A. The treatments consisted of an untreated control, and four rates of Co (29, 58, 87, and 116 g/ha). In the plant cane and second ratoon crops the following variables were determined: the number of leaves and tillers, stalk diameter, plant height, stomatal conductance (gs), chlorophyll index (SPAD), cane yield, sugar yield, and sugar quality (TRS, purity, fiber). For the first ratoon, it was only possible to determine the number of leaves, tillers, and plant height, as well as yield parameters. The plant-cane results demonstrate that foliar application of Co at 29 and 59 g/ha increased the number of open stomata, the number of leaves and tillers and the sugar yield. When Co was not applied to the first-ratoon crop, the effects on measured parameters were less pronounced, although positive effects on tillers were still observed. Results for the second-ratoon crop, showed positive benefits on stomatal conductance, the number of leaves and tillers, stalk heights, stalk weight, stalk diameter and sugar yield. Higher rates of Co (85 and 116 g/ha) decreased the growth parameters except the number of internodes and tillers during second ratoon crop. Results from this study demonstrated that foliar application of low levels of Co to sugarcane can increase sugarcane growth and yields. Further research is needed to optimize Co fertilization rates and to elucidate the effects of Co on plant hormone levels.