Abstract
ABSTRACT The spittlebug Mahanarva fimbriolata (Stal) (Hemiptera: Cercopidae) is one of the most important pest of sugarcane in Brazil. Population control measures are currently restricted to the use of chemical insecticides and the fungus Metarhizium anisopliae, in part because very little information exists regarding the resistance of sugarcane cultivars. Therefore, the aim of this study was to evaluate the resistance mechanisms of 18 sugarcane cultivars to M. fimbriolata to provide information for growers hoping to manage this pest. Isolated buds of each cultivar were planted in pots and maintained in a greenhouse for approximately three months. The pots were then moved to climate-controlled chambers (26 ± 1 oC; 70 ± 10% RH; 12 h photoperiod) to carry out laboratory tests to evaluate adult feeding and female oviposition preferences (using both free-choice and no-choice tests) as well as the effects of the cultivars on nymph development and the cultivars tolerance to the pest attack. The least attractive cultivar for adult feeding and oviposition in free-choice test was RB867515, which was also one of those that received the fewest eggs in the no-choice oviposition tests. Cultivar CTC9 showed the highest level of antibiosis resistance, with a root nymph survival rate of 52.5%. Finally, cultivar RB966928 was the most tolerant to M. fimbriolata, but it showed 19% reduction in aboveground biomass weight due to the pest.
Highlights
The spittlebug Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) is one of the most significant sugarcane pests in Brazil, causing yield reduction up to 50% and affecting sugarcane quality due to the reduction of stalk sugar levels and the increase of fiber content
In experiments testing the attractiveness of various sugarcane cultivars to adult M. fimbriolata, differences among cultivars in relation to number of adults found feeding, breeding, walking or resting among the leaves were observed in all evaluations (Table 1)
Cultivars SP80-1842 and SP81-3250, which were used as a standard for susceptibility, were less attractive to adults than RB855536, but they were some of the most attractive cultivars, differing from RB867515 and others cultivars (Table 1)
Summary
The spittlebug Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae) is one of the most significant sugarcane pests in Brazil, causing yield reduction up to 50% and affecting sugarcane quality due to the reduction of stalk sugar levels and the increase of fiber content. Losses extend to sugarcane industrial processes because the high fiber contents in stalks reduce milling capacity. These stalks are often cracked, deteriorated and contaminated and contaminants make sugar recovery difficult and inhibit fermentation (DinardoMiranda 2014). Differences among cultivars in relation to spittlebug populations and the damage caused by them were observed in experiments carried on field by Dinardo-Miranda et al (1999; 2001; 2004). In those works, even the least effected cultivars showed significant reductions in yield due to spittlebug infestation. Garcia et al (2011) and Dinardo-Miranda et al (2014; 2016) carried on studies in laboratory conditions and recorded differences among cultivars in relation to spittlebug populations and damage, few of could be considered resistant to the pest
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
