Survival of boll weevil (Coleoptera: Curculionidae) adults after feeding on pollens from various sources

Abstract

The survival of overwintering boll weevil, Anthonomus grandis grandis (Boheman), adults on non-cotton hosts in the Lower Rio Grande Valley (LRGV) of Texas was examined from 2001 to 2006. The success of the Boll Weevil Eradication Program, which was reintroduced into the LRGV in 2005, depends on controlling overwintering boll weevil populations. Laboratory studies were conducted using boll weevil adults that were captured in pheromone traps from September through March. The number of adults captured per trap declined significantly in the field from fall to the beginning of spring (3.5-7.0-fold). The proportion of trapped males and females did not differ significantly. The mean weight of boll weevil adults captured in September was 13.3 mg, while those of captured adults from November to February were significantly lower and ranged from 6.7 to 7.8 mg. Our results show that boll weevil adults can feed on different plant pollens. The highest longevity occurred when adults were fed almond pollen or mixed pollens (72.6 days and 69.2 days, respectively) and the lowest when they fed on citrus pollen or a non-food source (9.7 days or 7.4 days, respectively). The highest adult survival occurred on almond and mixed pollens [88.0%-97. 6% after 1st feeding period (10 days), 78.0%-90.8% after 3rd feeding period (10 days), 55. 0%-83.6% after 5th feeding period (10 days), and 15.2%-32.4% after 10th feeding period (10 days)]. The lowest adult survival occurred on citrus pollen [52.0%-56.0% after 1st feeding period (10 days), 13.3% after 3rd and 5th feeding periods (10 days), and 0 after 6th feeding period (10 days)]. Pollen feeding is not a behavior restricted to adult boll weevils of a specific sex or physiological state. Understanding how boll weevil adults survive in the absence of cotton is important to ensure ultimate success of eradicating this pest in the subtropics.

Survival pattern of the boll weevil during cotton fallow in Midwestern Brazil

“…According to Ribeiro et al (2010), pollen from different plant species found in remnants of Cerrado vegetation is used by adult boll weevils during the intercrop period. Therefore, areas of natural vegetation, such as the Cerrado, may be sources of alternative food due to the diversity of plants, as can be the case with any environment, even a cultivated field, which provides alternative food, as found by Spurgeon & Raulston (2006), Showler (2006), and Greenberg et al (2007).…”

Fontes Alternativas De Pólen Utilizadas Pelo Bicudo-Do-Algodoeiro Em Duas Regiões Produtoras De Algodão Na Bahia

“…Sabe-se que durante a entressafra o inseto pode utilizar algumas estratégias de sobrevivência que possibilitam a manutenção de suas populações na safra seguinte, dentre elas a capacidade de se alimentar de pólen de muitas famílias de plantas, como relatado por diversos autores (CUADRADO e GARRALLA, 2000;CUADRADO, 2002;GABRIEL, 2002;GREENBERG et al, 2007;JONES, GREENBERG, EISCHEN, 2007;RIBEIRO et al, 2010).…”

Alternative foods for the multicoloured Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae)

“…The numbers of pollen grains recorded in the gut of H. axyridis were similar to or higher than those found in other beetle species that occasionally exploit pollen in the field. The western rootworm Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) is reported to have 40 to 120 pollen grains in its gut (Moeser & Vidal, 2005) and the boll weevil Anthonomus grandis grandis (Boheman) (Coleoptera: Curculionidae) 2 to 25 pollen grains (Greenberg et al, 2007). The amount of pollen consumed by insects varies greatly among species depending on whether it is an essential food supporting development and/or reproduc-tion, as in female hoverflies (Hickman et al, 1995;Irvin et al, 1999), or merely a supplementary or alternative food sustaining survival for a short period of time, as in boll weevils (Greenberg et al, 2007).…”

“…The western rootworm Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae) is reported to have 40 to 120 pollen grains in its gut (Moeser & Vidal, 2005) and the boll weevil Anthonomus grandis grandis (Boheman) (Coleoptera: Curculionidae) 2 to 25 pollen grains (Greenberg et al, 2007). The amount of pollen consumed by insects varies greatly among species depending on whether it is an essential food supporting development and/or reproduc-tion, as in female hoverflies (Hickman et al, 1995;Irvin et al, 1999), or merely a supplementary or alternative food sustaining survival for a short period of time, as in boll weevils (Greenberg et al, 2007). In the present study, fertile H. axyridis adults fed in the laboratory on only ad libitum quantities of pollen had about 35000 pollen grains in their gut, indicating that the majority of field collected H. axyridis adults had only ingested small amounts of pollen and that it may only be a supplementary source of nutrients for this coccinellid.…”