A new formulation of oxalic acid for Varroa destructor control applied in Apis mellifera colonies in the presence of brood

Abstract

-An organic product based on oxalic acid was evaluated for use in Varroa control under spring/summer climatic conditions in Argentina. The formulation consists of four strips made of cellulose impregnated with a solution based on oxalid acid. Forty-eight beehives were used to assess the product efficacy. Residues of the product were also tested in honey, bees, and wax. Each trial had respective control groups without oxalic treatment. At the beginning of the experiment, four strips of the formulation were applied to the colonies belonging to the treated group. Falling mites were counted after 7, 14, 21, 28, 35, and 42 days. After the last count, the strips were removed and colonies received two flumethrin strips for 45 days. Falling mites were counted throughout this period. Average efficacy of the organic product was 93.1 % with low variability. This product is an organic treatment designed for Varroa control during brood presence and represents a good alternative to the synthetic treatments.Varroa destructor / control / oxalic acid / bee brood / Argentina

Honeybee health in South America

“…The development of new acaricides from plants (propolis, essential oils, organic acids) is a key factor to revert this situation. In this sense, some recent studies report promising molecules for Varroa control (Damiani et al 2010(Damiani et al , 2014Maggi et al 2015 among others).…”

Assessing in Vitro Acaricidal Effect and Joint Action of a Binary Mixture Between Essential Oil Compounds (Thymol, Phellandrene, Eucalyptol, Cinnamaldehyde, Myrcene, Carvacrol) Over Ectoparasitic Mite Varroa Destructor (Acari: Varroidae)

“…The details of this acaricides formulation can be found in a study by Maggi et al (2015), which consisted of one application per year. The hives were treated up to ten months before the tests performed in this study.…”

An Overview on Honeybee Colony Losses in Buenos Aires Province, Argentina

“…According to Antúnez et al (2017) 28% of annual losses were estimated in Uruguay. In Argentina, even though there are no documented cases, several records of beekeepers suggest a 30% of losses in the last years (Maggi et al, 2014). Particularly in Buenos Aires province, a survey over 200.000 colonies showed that 54% of producers had less than 10% of dead hives, 33% between 10-20%, and 13% more than 20% (Reynaldi & Guardia López, 2011).…”

“…In recent years, some cases of CCD have also been reported in Asia and South America (Farooqui, 2013;Antúnez et al, 2017) but there are not any documented cases in Africa or Oceania. In South America, particularly in Argentina, even though there are no documented cases, several records of beekeepers suggest a 30% of losses in the last years (Maggi et al, 2014). In 2017, 154 out of 170 commercial colonies nucleated in three apiaries from General Alvear (35°55′ 23.67″S, 59°57′29.58″W), Buenos Aires province showed the sudden massive loss of their bees and died at the end of summer, according CCD symptoms.…”