The development of the sugarcane-based industry and of the green sugarcane harvesting system, considering environmental, agronomic, economic and safety aspects, made it possible to reach the current stage of efficiency. However, such changes cause impact on the existing fauna and flora in sugarcane plantations. Specifically as related to pests, the crop residue is left on the ground after the harvest and the accumulation thereof in layers after successive cuts favors the occurrence of a variety of species.

The sugarcane spittlebug, Mahanarva fimbriolata, was the species that best adapted to the new harvesting system, and while having previously been classified as a secondary pest, it came to rank as a key pest of the crop, requiring special attention in terms of management and control, during the hot and humid season of the year. 

The main factors that influenced this change were: the prohibition to burn sugarcane plantations, a factor that allowed spittlebug eggs to remain at the base of the stumps and of the crop residue layer, providing the adequate micro-climate and protection to allow the species’ nymphs to develop.

This negative aspect notwithstanding, one observes that these same environmental conditions favor control efficiency of microbial agents, mainly the fungus Metarhizium anisopliae, used by many producers. The second species that benefitted from the green sugarcane harvest is  the sugarcane weevil, Sphenophorus levis, which found the ideal environment and protection for its development and reproduction.

The burning prohibition also allowed for the survival of most adults, responsible for infesting new buds and ratoon tillers at the beginning of the harvest. This  pest deserves special attention because of the losses it causes, requiring the application of integrated control methods, to reduce populations and damage.

Monitoring pest populations and the control activities starting with the reform of infested plantations, the use of healthy seed cane, free of pests, in the planting, and the application of pesticides and microbial agents, are control methods that should be used.

The change made in the harvesting system also helped to control pests, particularly the Elasmo borer, Elasmopalpus lignosellus, which did not find suitable conditions for its development under crop residue layers, along with the fact that adults are less attracted to the green sugarcane crop in comparison with burned sugarcane.

There was an increase in population of woodworms living on sugarcane plantations, acting as decomposers of cellulosic material, thereby being beneficial to the production system, while not causing any damage to the crop. With respect to woodworms classified as pests, no significant increase in population and damage was observed, at comparable levels in the two harvesting systems.

Experiments were undertaken comparing populations of the sugarcane borer, Diatraea saccharalis, and those of its predators and parasitoids in green sugarcane areas and burned sugarcane areas. Field results obtained in several regions indicate a trend towards higher population levels in green sugarcane areas, with infestation intensity levels in line with such population levels.

The possible population increase of this pest requires adapting monitoring methods and increasing the number of species and approved biological control agents, in areas in which the pest’s population density is found to be medium to high. Leaf cutter ants, mainly Atta ants, are responsible for significant losses in agriculture and merit all attention to their monitoring and control.

In green sugarcane harvesting areas it is more difficult to localize and measure the size of anthills in the initial stage of ratoon growth, it being necessary to wait two or three months after the harvest before beginning control activities. No increase in anthills was noticed as the result of the harvest method chosen.

An increase in the number of Scarab beetles occurred in green sugarcane harvest areas, but one also observes the constant presence of the Bothynus medon species that exclusively feeds on crop residues to be found on the ground, after taking them inside underground galleries and chambers that open up at a depth of about 50 cm, and which is not considered a pest.

With respect to other larvae species, outbreaks occur in some areas, but there is a lack of taxonomic and bioecologic studies of this group. The two giant borer sub-groups, Telchin licus licus and Telchin licus laura, may be favored by the green sugarcane harvesting system and may induce a system change from the current control system based on grabbing or spearing, given that the base of the cut off stalks will be covered by crop residues.

One sees that there is a need for adapting pest monitoring and control methods in sugarcane plantations, due to changes in the harvesting system, varieties and other crop characteristics.