However, these differences are apparent even in the absence of
aerenchyma that improves gas exchange between the shoots
and roots in plants growing in waterlogged soils. Voesenek et al.
(1999) measured oxygen concentrations in the roots of B. napus
cultivars, as well as the radial oxygen loss from the roots and
concluded that the lack of aerenchyma development and the
high rate of leakage of oxygen from the roots contributed to the
inability of these plants to adapt to water logging.