The study of biological control of mistletoes

The semi-parasitic plants, mistletoes are one of the most important pathogenic agents in the forest societies of lran, particularly in the fars and kohgiloyeh and BoyerAhmad procinces. For determination of the species of mistletoes and identification of their hosts. Were carried out in numerous excursions through the collection of the host samples which were parasited by the mistletoes in different seasons, during 1375-6 to this parasite three representative stations with different cover types were selected. The saverse mountain station with 6246 ha area, represents the Amygdalus spp. and Cratagus spp. Assoxiation, the Tangsorkn mountain station, With 4500 ha extent, represents the pyrus spp. and the kohva mountain stations, with 4904 ha expause, represent, Amygdalus spp, and Acer spp. associations. Samplings were performed in 250* 750 m plots, one the each station. Elevation, exposure, volume of crown trees, and slope of each plot were determined. The infected and healthy bushes were counted.fruits of 60 branches of the infectes and healthy bushes were also colleted and weighted. 1- Nine scrb species (Amygdalus lycioides Spahc. Pyrus glarba Spach. Species Cratagus spp. A. scoparia Spach, Acer monospessulanum Spach. Cotoneaster persica Spach , Amygdalus eburnea Spach. And Cerasus microcarpa Spach. Were found to be infected with mistletoe. These plants inhabit all exposures above the 1400m MSL. 2- Forest trees inhabit in southeastern, southen, and southwestern southen, and southwestern exposures were more parasited than the bushes on ther exposures. Preference of birds wich carry the parasite for the warmer sites maybe one reason for the prevalence of mistletoes on those warmer exposures. 3- The species of mistletoe in kohgiloyeh & Boyerahmad province,s forest societies was indentifieted Loranthus grewingkii. Spach (Loranthacea). This parasite wich bars red and green fruits. 4- Another specimen of mistletoe, which bears yellow fruits maybe a variety of L. gewingkii. Distributionm, the host rage and the extent of parasitism of this kind is less than those of the red-fruited species. 5- The weights of the fruits form the healty plants. Differend significantly form those of the infected bushes. 6- Those portions of the branches located above the infection center were usually dead. There were prevalence of diffigured and dead trees in the severly infacted stands. 7- One genus of grass-hoper (Melanoplus sp.) eaten the leaf of present mistletoes. 8- A few of fungi in Deutromysetes and Ascomycetes group does infected of mistletoes, that probably be used for biological control.