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POLLINATION OF BLUEBERRIES, STRAWBERRIES AND BLACKBERRIES 



James N. Moore 

 Department oF Horticulture and Forestry 

 University of Arkansas, Fayetteville, AR 



Knowledge of the pollination requirements of fruit crops is essential 

 to fruit producers, since the potential magnitude of the crop is determined 

 by the extent of successful pollination and fertilization of the flowers at 

 the time of bloom. An understanding of the mechanisms of pollination of his 

 fruit crops enables a fruit grower to provide those conditions which lead to 

 satisfactory fruit set. 



B 1 ueber r ies 



At the outset, we can make two definite statements concerning pollina- 

 tion of blueberries: 1) insect pollination is obligatory and 2) bees are 

 the principal pollinators. 



The necessity of insect pollination of blueberries is determined by the 

 morphology of the flower. The blueberry flower has all the characteristics 

 of an entomoph i lous (insect attracting) flower. These characteristics are: 



1. Corolla of the flower in shape of a tube, opening only at tip 

 (prevents wind pollination). 



2. Pistil of flower extends well beyond anthers, and stigma flanged to 

 inside, preventing unaided self-pollination. 



3. Nectary glands produced at base of ovary to attract insects. 

 h. Fragrance produced to attract insects. 



5. Pollen heavy, clumping, not readily wind-borne. 



Thus, the construction of the flower effectively suppresses both wind 

 pollination and unaided self-pollination. However, as insects enter the 

 corolla tube seeking the nectar at the base of the ovary, their bodies 

 collect pollen as they rub on the anthers and deposit pollen on the exposed 

 stigmas of flowers subsequently visited. 



Numerous research studies using various types of caging have shown that 

 bees are the principal effective pollinators of the blueberry. Most repor- 

 ters state that both honeybees and bumblebees are effective pollinators, but 

 in many blueberry producing areas, native bee populations are considered 

 inadequate for complete pollinations, and honey-bee colonies are introduced 

 into the fields. 



