In thallous plants, the gametophyte can be an extended thallus, not very differentiated, provided with rhizoids on the lower face, these rhizoids are elongated uni or pluricellular tubes, similar to root hairs than to the roots of vascular plants.
These liverworts are especially abundant in tropical and subtropical areas, in regions of abundant rainfall and high humidity, but are also present in abundance in temperate regions.
The shape of the cells can be very variable, from isodiametric to rectangular. The cell walls may be uniformly thin or thickened, or have collenchymatous thickening called trigones. These structures may have triangular, chordate or stellate shapes.
In fresh material, the cells usually contain chloroplasts and oleocortexes. Some liverworts have rows of elongated cells in the middle zone of the lamina called vita. Unlike the true costa, the vita is only a thickened area.
Bryophytes are a group of plants characterized by having a photosynthetic and dominant gametophyte (almost always perennial), monosporangiate sporophytes, and little differentiation of conductive tissues. These three important characteristics differentiate them from other groups of plants: ferns, gymnosperms and flowering plants.
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They are all herbaceous perennial plants, with a subway rhizome from which arise adventitious roots and greenish aerial stems with whorled branches and in which an arcuate structure can be distinguished due to the presence of nodes and internodes.
The stem has a complex structure due to the presence of a series of canals and ducts as shown in the diagrams below. There is an epidermis covering the entire outer surface of the stem, which is differentiated into ridges or projections called carinae and valleys or inlets called valleculae, where subepidermal stomata are arranged in rows, which are orifices through which gas exchange takes place. It is normal that some epidermal cells are silicified to provide resistance and protection against herbivores.
The sporangia are located in strobili (see figure 1), which can be found in vegetative branches or in others that lack chlorophyll, such as the one in the photo above, called sporogenous or fertile, present in Equisetum arvense and E. telmateia, although there is an intermediate case such as E. sylvaticum, in which the branches turn green when the spores are released.
MORPHOLOGY: Click beetle larvae, called wireworms, are generally saprophagous and live on dead organisms, but some species are serious agricultural pests and others are active predators of other insect larvae. Adults are typically nocturnal and phytophagous.
HABITAT: Some are saprophagous, are subterranean in habit, have the ability to rapidly locate food by following carbon dioxide gradients produced by plant material in the soil and germinating seeds (Doane et al. 1975). In the case of chocho seed, the release of CO2 is an attractant of wireworms and Delia sp.
ALTERNATIVE CONTROLS: Their remarkable ability to recover from diseases induced by exposure to insecticides (sometimes after many months) (Van Herk et al. 2008), make them difficult to exterminate once they have begun to attack a crop. Methods for pest control include crop rotation and cleaning the soil of insects before planting.