parasitic plant communicates with the host plant through Haustorium - special bodies that arise from the conversion of the embryonic root or, more rarely, of the stem.Now there are more than 4,100 species of parasitic plants that belong to 19 families.
parasitic plants are classified according to three criteria.The first criterion for classification is dependent on the host plant or plants of the donor.By this measure, allocate obligatory parasites, unable to stand on its own, and facultative parasites that can extract nutrients from the environment without the aid of another plant.
Another criterion for classification is the source of formation of haustoria.Stem parasites are plants whose bodies due to host plant evolved from the stems.Root parasitic plants have haustoria formed from the roots.
presence or absence of photosynthetic capacity of the plant parasites are also divided into two groups.Goloparazitami called plant organs which contain virtually no chlorophyll.They do not carry out the process of photosynthesis and are completely dependent on the host plant.Goloparazity always belong to the group of obligatory parasites.Semiparasites typically have green leaves and stems, and are capable of photosynthesis, partly providing themselves nutrients.From donor plant they are advantageously water and minerals.
basis of classification of plant pests, semiparasites have two additional features and goloparazity divided only by the source of formation of haustoria.So, they are dodder stem goloparazitami and hydnora spp.- Root goloparazitom.Semiparasites have a more complex classification.For example, the East Australian Christmas tree is an obligate root poluparazit, mistletoe - obligate stem poluparazit, rattle - optional root poluparazit.
most famous plant parasites are members of the family rafflesiaceae.These plants are almost entirely located in the root or stem of the plant donor, letting out flowers.This family includes Rafflesia Arnold, which has the largest flowers of up to a meter in diameter, with a characteristic putrid smell.
the south of Russia on the branches of the trees you can see the mistletoe - a parasitic plant of the family sandal.It is spherical, an evergreen shrub.This successfully implements plant photosynthesis, and water and minerals receives from the host plant.