Pollinator attraction and efficacy vary among chili pepper varieties

Insect pollinators play a critical role in sustainable agriculture, enhancing the yield of many crops. The contributions of insect pollinators to yield and profitability are often overlooked, however, when growers select crop varieties. Traits such as yield potential, disease resistance, and marketability tend to be prioritized. The objectives of this study were to: (1) quantify differences in pollinator attraction among 15 chili pepper (Capsicum annuum) cultivars, (2) correlate floral and vegetative traits to pollinator attractiveness, and (3) determine whether variation in pollinator visitation affects the yield of each variety. Pollinator attraction in fifteen genetically distinct Capsicum annuum cultivars was evaluated through open-field surveys at the Arkansas Valley Research Center in Rocky Ford—a region in southern Colorado where chili pepper is an economically important crop. Cultivars with diverse morphological traits were selected (e.g., petal length and anther size) and vegetative traits such as leaf density and plant height. Initial results suggest that varietal differences are associated with variations in pollinator activity. Pollinator attraction across the Capsicum annuum varieties was positively correlated with corolla diameter, pollen availability, and plant height. Members of Halictidae, Syrphidae, and Vespidae were the most common pollinator families observed in the field. Pollinator attraction varied by up to 433% among cultivars, with Charger being the most attractive (.192 average visits per minute) and Mosco being the least attractive (.036 visits per minute). Pollinator visitation was strongly correlated with yield in some varieties, but not all, with up to a 54.4% increase in pepper mass observed in Charger.