Characteristics of the tomato fruit (Solanum lycopersicum) using native bumblebees (Bombus atratus) as pollinators in greenhouse

Abstract

In Uruguay, the production of tomato (Solanum lycopersicum) in greenhouse presents pollination issues that limit its yield. The use of bumblebees (Bombus spp.) as pollinators can help overcome this problem as they perform “buzzing pollination”, a behavior that makes them excellent pollinators of Solanaceae and particularly tomato. The aim of this study was to evaluate the effect of the native bumblebees Bombus atratus on the proportion of fruit set, weight, diameter, number of seeds and number of locules of tomato (lapataia and elpida varieties). An experience was carried out in Canelones, where the fruits from flowers pollinated by bumblebees and from flowers not visited by insects were compared; two other experiences carried out in Salto were similar to that of Canelones, but included flowers treated with hormones. In the three analyzed greenhouses the visit of bumblebees to the flowers increased the proportion of fruit set by 13 - 47%, compared to the result obtained in flowers not visited by the insects. Also, the pollinating action of bumblebees significantly improved the weight, size, and number of seeds compared to fruits obtained from flowers without access to pollinators. This improvement was recorded in the experience in Canelones and only in one of the Salto's experiences. On the other hand, a positive correlation was found between the number of seeds and the weight (R² = 0.37, R² = 0.53; lapataia, elpida, respectively) in the two tomato varieties. This study is the first in Uruguay to show the benefits of using native bumblebees in tomato production in greenhouses.