Size of stomata and palisade parenchyma on cotyledon adaxial side in someBrassica oleracea L. varieties
Cotyledons of 15 day-old seedlings of fiveBrassica oleracea L. varieties were surveyed to identify salient anatomical features. Both palisade parenchyma cells present in the first subepidermal layer and stomata were found to differ in size.
Anatomical characteristics of the epidermis in some cultivars ofBrassica oleracea L. distribution and structure of stomata in the cotyledons
The blade area and the number of stomata were studied in the cotyledons of five cultivars ofBrassica oleracea L., cultivated in a growth chamber and in the greenhouse, respectively. Characteristic differences between different varieties were found in the number of stomata per unit area as well as in their occurrence on both the adaxial and abaxial surfaces.AbstractU pěti kultivarůBrassica oleracea L., vypěstovaných v klimatizovaném boxu a ve skleníku, byla sledována piocha cepele děložnich listů, pocet průduchů na jednotku plochy a jejich rozložení na adaxiálni a abaxiálni stranċ čepele děložniho listu.
Control of rooting and the pattern of senescence in detached white mustard cotyledons.
Senescence of detached mustard cotyledons was greatest in full light or at low light intensity but was reduced at intermediate light intensities. The location of yellowing in the blade depended on the conditions in which it was maintained after excision. Cotyledons cultured at full light intensity in the absence of exogenous nutrients formed roots at the base and yellowed around the margins. Reduction in light intensity and increasing nutrient concentrations resulted in an increasing proportion of the cotyledons yellowing from the base upwards, and fewer developed roots. At low light intensity with high nutrient levels rooting was suppressed and basal senescence predominated. 
 
 
 
The location of yellowing in the cotyledon may be associated with mobilisation gradients induced by the differential effects of light and mineral nutrient level on root initiation and blade growth.