Abstract
In 2004 and 2006-2008, a study was conducted on the effect of pollinating insects on the fruit, seed set, and development of two cultivars of blue honeysuckle Lonicera caerulea (Sevast.) Pojark.: "Atut" and "Duet". The experiment was carried out in south-eastern Poland, at the Experimental Farm of the University of Life Sciences in Lublin, Poland. Flowers accessible to pollinating insects throughout the whole flowering period, set fruit at a very high percentage. The study average was 90.57% for "Duet" and 88.08% for "Atut". During self-pollination under isolation, on the other hand, the percentage of fruit-bearing flowers was low. In the case of "Atut" the average was 9.37%, whereas for "Duet" it was 23.85%. Multiple fruits formed from isolated flowers had a 45-50% lower weight, on average, than those developed from flowers accessible to pollinating insects. The pollination mode was found to have a significant effect on the number of seeds produced in the multiple fruit. Flowers which were isolated to prevent insect foraging did develop multiple fruits, characterized by a significantly lower number of seeds. The recent studies confirm that several cultivars should be planted on honeysuckle acreage. The presence of managed pollinators can increase quantity and improve quality of fruit yield in honeysuckle.