PALYNOLOGICAL STUDIES FOR SOME CULTIVATED SPECIES OF PINUS L., 1753 (PINALES, PINACEAE) IN EGYPT

Abstract

Pollen grains of the five cultivatedspecies ofPinusL.,1753 from Subsect. Pinaster(Order Pinales, Family Pinaceae) were collected from the Orman Botanic Gardens at Giza in addition to the herbarium specimens. They were examined by light and scanning electron microscopy to detect the taxonomic value of their pollen characteristics. The pollen grains were bisaccate. An artificial key constructed according to the morphology of pollen grainsrecognizes the five species that belong to Pinus:P. pinea Linnaeus, 1753;P. canariensis Smith, 1828;P. halepensisMiller, 1768;P. roxburghiiSargent, 1897; andP. brutiaTenore, 1811. The differential items included the presence or absence of apertures, e.g. the monosulcate colpus that presentsin P. pinea and P. brutia; pollen shape without sacci that could be perprolate as in P. pinea or prolate as in the remaining species; pollen shape (outlined with sacci) in polar view that could be haploxylonoid as in P. pineaandP. roxburghiior diploxylonoid as in the remaining species; in addition to cappa and sacci exine sculpture. A dendrogram from the Community Analysis Package statistical program for data analysis supported the separation of five species ofPinusinEgypt and showed thatP. canariensisandP. halepensiswere closely related, as well asP. brutiaandP. roxburghii. The cluster separatedP. pineainto a separate group, but it was more closely related toP. canariensisandP. halepensis.The cluster tree was illustrated, visualized, and confirmed by a heat map based on the R programming language for effective manipulation of the data.

Keywords

• cultivated trees
• data analysis
• egypt
• pinus