Soybean and Bees

Bees and plants relations
Nectar, a key mediator
Nectar is an aqueous, sweet plant secretion, which mediates plant interactions with pollinators
and defenders, sometimes protecting against robbers and microorganisms by secondary
compounds and antimicrobial proteins, present on its composition (Heil, 2011). Nectar
contains water, sugars and amino acids to attract pollinators and defenders and is protected
from nectar robbers and microorganisms by secondary compounds and antimicrobial proteins.
Floral (FN) and extra floral (EFN) nectar secretion can be induced by jasmonic acid, it is
often adjusted to consumer identity and consumption rate and depends on invertase activity.
Invertases are likely to play at least three roles: the uploading of sucrose from the phloem,
carbohydrate mobilization during active secretion and the post secretory adjustment
of the sucrose:hexose ratio of nectar (LINDEN and LAWHEAD, 1975). However, according to
Heil (2011), it remains to be studied how plants produce and secrete non-carbohydrate components,
and more research is needed to understand how plants produce nectar, the most
important mediator of their interactions with mutualistic animals.
Proctor et al. (1996) point that floral nectar must be understood as a key reward offered by
plants to their pollinators, aiming to attract them and get their loyalty. Fahn (1979) describes
nectar as a plant exudate, secreted by glandular tissues located on various floral parts. They
are so important that its structure and features are largely considered in plant taxonomy
and phylogeny.
Nectar can be secreted on virtually all plant organs (except roots), and the site of secretion
usually coincides with its function, although nectaries that are functionally extra floral (EF)
might be found inside the inflorescences, though not involved in pollination (Elias, 1983).
According to Brandenburg et al. (2009) and De La Barrera and Nobel (2004), many angiosperm
and some gymnosperm species produce floral nectar (FN) to attract insect or vertebrate
pollinators to achieve adequate fertilization and outcrossing. On the other side, ex-
SoybeAn and bees
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