The studies concerned the variability in nectar and pollen production in flowers of 75 double-low lines of white mustard (Sinapis alba L.) and a reference cultivar ‘Nakielska’. Also, rates of insect visitation to flowers in 19 lines were investigated. Significant genotypic differences were found in nectar amount, sugar concentration in nectar and total nectar sugar amount. The average nectar amount/10 flowers varied from 2.3 to 24.4 mg, with a mean 14.7 mg for ‘Nakielska’. Nectar concentration for most lines exceeded 20%. The majority (52%) of the lines tested produced more than 2 mg of sugars/10 flowers in nectar. The average amounts of pollen varied from 1.2 to 12.0 mg/10 flowers, with the mean 8.5 mg for ‘Nakielska’. No clear genotypic effect on the amount of pollen/10 flowers was demonstrated. The lines did not differed significantly in their attractiveness to flower visitors. The main foragers were honey bees (93% of all visiting insects). It is concluded that the double-low lines of S. alba are comparable to conventional cultivars in their potential for nectar flow but perform poorer as pollen producers.

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