Plant Extrafloral Nectaries

It is well known that plant flowers produce nectar that is important in encouraging pollination, as well as providing food for bats, birds and insects. However, few people are aware of plant extrafloral nectaries that are nectar-producing glands physically apart from the flower. Extrafloral nectaries have been identified in more than 2,000 plant species in more than 64 families. For example, in nine cerrado areas of Brazil’s São Paulo and Mato Grosso states, the plant families Mimosaceae, Bignoniaceae and Vochysiaceae contained the highest frequency of extrafloral nectaries.

Several review articles dealing with extrafloral nectaries or related ecological relationships and at least one book is available. In this article we briefly summarize some aspects of current knowledge about plant extrafloral nectaries and discuss their role and significance to parasitic and predatory arthropods that are important biological control agents.

Fig. 806

Ants frequently visit the nectaries of the vine Smilax...