Effect of fallows on population dynamics of Cosmopolites sordidus: toward integrated management of banana fields with pheromone mass trapping

Abstract

1 The banana weevil Cosmopolites sordidus Germar (Coleoptera: Curculionidae) is the most serious pest of banana and plantain in most production areas, including the West Indies. 2 During a period of 2 years, we assessed the efficacy of a pheromone masstrapping control strategy of C. sordidus in field conditions in Guadeloupe at different cropping stages, both in sanitation fallows and in different ratoon banana crops. 3 In the fallows, catches peaked 3 months after beginning trapping and then decreased to zero after 9 months. By contrast, for the new plantations, the catches of C. sordidus increased after the 11th month and, in the older banana fields, there was no decrease in C. sordidus catches. The C. sordidus catches increased in the neighbouring banana plots, whereas they decreased in the fallows, and these catches decreased with the distance from fallow. 4 In conclusion, mass trapping with synergized pheromone traps within fallows should allow better sanitation of banana plantations. Yet, within the farms, fallows must not be located next to new plantations to avoid massive damage to the young plants.More generally, the present study emphasizes that the control of this insect should be managed at the farm scale and not at the field scale, with special attention being paid to the location of fallows.

Characterization of olfactory sensory neurons in the white clover seed weevil, Apion fulvipes (Coleoptera: Apionidae)

“…Pest management in clover seed production would therefore greatly benefit from development of odor-based strategies for weevil control. For instance, mass-trapping using aggregation pheromones, sometimes in combination with host plant volatiles (Guarino et al, 2011), has been successful for other weevil species (Cross et al, 2006;Rhino et al, 2010;Smith, 1998). In addition, plant compounds from both hosts and non-hosts might act as anti-attractants, like in many species of bark beetles (Andersson et al, 2010;Zhang and Schlyter, 2004).…”

A farmer participatory research approach to assess the effectiveness of field sanitation and regular trapping on banana weevil populations

“…Unfortunately, the present study could not provide a clear answer to whether migration occurred from the clean to dirty area because the populations in the three dirty areas were not monitored between the initial and final population estimates. Rhino et al found that, by leaving banana fields fallow, weevil migration into adjacent active banana fields was initiated [18]. This indicates that weevil migration from clean to dirty areas might have contributed to the changes in populations in our experiment.…”

“…Reports of high variation in weevil infestation levels on neighbouring farms growing the same banana varieties suggest that field management may affect weevil population size and distribution [15][16][17][18].…”

“…Larval survival may be higher in residues due to the breakdown of plant antibiotic resistance in decaying tissue [22]. There has been some concern about possible immigration of weevils from neighbouring fields into areas where control methods are employed [16,18,23]. Weevils have recently proven to be able to move considerable distances by nocturnal crawling [24].…”

“…Weevils have recently proven to be able to move considerable distances by nocturnal crawling [24]. Field sanitation, through removal of post-harvest banana residues and weeds, is a cultural control method which seeks to discourage weevil oviposition, and could lead to the emigration of weevils, such as occurs in fallows [18]. By removing resources attractive to the weevils, a dispersal of weevils into neighbouring fields could be promoted.…”