Plant pathology pathological plant anatomy which is the

ﻋﻼﻗﺔ ﻋﻠﻢ ﺗﺸﺮﻳﺢ ﺍﻟﻨﺒﺎﺕ ﺑﺎﻟﻌﻠﻮﻡ ﺍﻟﻨﺒﺎﺗﻴﺔ ﻭﺍﻟﻌﻠﻮﻡ ﺍﻟﻌﺎﻣﺔ ﺍﻷﺨﺮﻯ Plant pathology : ﻋﻠﻢ ﺃﻤﺮﺍﺽ ﺍﻟﻨﺒﺎﺕ pathological plant anatomy, which is the study of the effect of disease producing agents of a biological, physical, and chemical character on plant structure. : ﻋﻠﻢ ﻓﺴﻴﻮﻟﻮﺟﻴﺎ ﺍﻟﻨﺒﺎﺕ Plant physiology physiological plant anatomy, which is concerned with the links existing between plant structure and internal processes. Plant taxonomy : ﻋﻠﻢ ﺗﺼﻨﻴﻒ ﺍﻟﻨﺒﺎﺕ Comparative, or systematic, plant anatomy, which introduces the comparative study of representatives of the different systematic groups (taxa)—species, genera, families. Plant chemistry : ﻋﻠﻢ ﻛﻴﻤﻴﺎﺀ ﺍﻟﻨﺒﺎﺕ Food sciences : ﻋﻠﻢ ﺍﻷﻐﺬﻳﺔ : ﺃﻬﻤﻴﺔ ﻋﻠﻢ ﺗﺸﺮﻳﺢ ﺍﻟﻨﺒﺎﺕ ﻓﻲ Paper industry ﺻﻨﺎﻋﺔ ﺍﻟﻮﺭﻕ Tissues industry ﺻﻨﺎﻋﺔ ﺍﻷﻨﺴﺠﺔ Wood industry ﺻﻨﺎﻋﺔ ﺍﻷﺨﺸﺎﺏ

Cambium ﻭﺍﻟﻤﻮﻟﺪﺓ meristems ﺍﻷﻨﺴﺠﺔ ﺍﻻﻧﺸﺎﺋﻴﺔ : ﺃﻮﻻ ( ﺍﻟﺨﻼﻳﺎ ﺍﻟﻘﺎﺑﻠﺔ ﻟﻼﻧﻘﺴﺎﻡ Greek) ﻓﻲ ﻳﻮﻧﺎﻧﻴﺔ Meristos ﺗﻌﻨﻲ ﻟﻔﻈﺔ able to divide ( ﺍﻟﺨﻼﻳﺎ ﺍﻟﻘﺎﺑﻠﺔ ﻟﻠﺘﻐﻴﺮ Greek) ﺑﺎﻟﻼﺗﻴﻨﻴﺔ Cambium ﺗﻌﻨﻲ ﻟﻔﻈﺔ able to change Characters of Meristematic cells. The cells of the meristematic tis sues are quite distinct in their cytologi caland physiological characteristics from other cells. The following are the characteristics of the meristematic cells. 1. Cells have the power of active division. 2. They are compactly arranged in tissue and there is absolutely no intercellular space. 3. The cell wall is thin and primary in nature, containing only cellulose. It is uniformly thick. There is no secondary thickening. 4. Cells possess dense protoplasm with a prominent large nucleus compared to other cells of equal volume. 5. Vacuoles are small or absent to tally. 6. Cells do not possess ergastic sub stances. 7. Mitochondria and endoplasmic reticulum are very little differentiated. 8. Plastids, when present, are in protoplastid stage. 9. Cells contain relatively more number of ribosomes. 10. Cells are metabolically very active. When cells of the meristem divide, the daughter cells get differentiated into mature types while the others re main meristematic. For this reason, the meristems perpetuate and become con tinuous source of cell formation.

Classification of meristematic tissues ﺗﺼﻨﻴﻒ ﺍﻷﻨﺴﺠﺔ ﺍﻻﻧﺸﺎﺋﻴﺔ : ﺛﺎﻧﻴ Primary meristemaic Tissues : ﺃ( ﺍﻷﻨﺴﺠﺔ ﺍﻻﻧﺸﺎﺋﻴﺔ ﺍﻻﺑﺘﺪﺍﺋﻴﺔ A primary meristem arises in the tissue of the embryo and continues to exist in the plant organ in which it rose. The primary meristem found at the tips of stems or roots is called the apical meristem which is responsible for increase in length as it gives rise to the first or primary permanent tissues. According to origin ﻋﻠﻰ ﺃﺴﺎﺱ ﺍﻟﻨﺸﺄﺔ 1 : ﺏ( ﺍﻷﻨﺴﺠﺔ ﺍﻻﻧﺸﺎﺋﻴﺔ ﺍﻟﺜﺎﻧﻮﻳﺔ secondary meristemaic Tissues Secondary meristematic tissues are those which arise as new meristematic in non meristematic or permanent tissue, later at a certain stage of development. Sometimes the permanent tissues develop the power of division and form secondary meristems.

: Parenchyma tissue ﺍﻟﻨﺴﻴﺞ ﺍﻟﺒﺎﺭﻧﺸﻴﻤﻲ : ﺛﺎﻧﻴ ﺑﺎﻟﻴﻮﻧﺎﻧﻴﺔ ﺍﻟﻮﺣﺪﺍﺕ ﺍﻟﻤﺘﺠﺎﻭﺭﺓ Parenchyma ﺗﻌﻨﻲ ﻟﻔﻈﺔ (para =beside & enchyma = ﻭﺍﻟﻤﻠﺘﺤﻤﺔ ﻭ ﻫﺬﺍ ﺍﻟﻮﺻﻒ ﻳﻨﻄﺒﻖ ﻋﻠﻰ ﺍﻟﺨﻼﻳﺎ ﺍﻟﺘﻲ ﺗﻜﻮﻥ. infusion) ﺣﻴﺚ ﺗﻜﻮﻥ ﺍﻟﻮﺣﺪﺍﺕ ﻣﺘﺠﺎﻭﺭﺓ ، ﻧﺴﻴﺞ ﺍﻷﺴﺎﺱ ﻓﻲ ﺍﻟﻨﺒﺎﺕ ﻭﻣﺘﻤﺎﺳﻜﺔ ﻭﻣﻠﺘﺼﻘﺔ Characters : ﺍﻟﺨﺼﺎﺋﺺ parenchyma is most simple and unspecialized primitive tissue. it mainly consists of thin walled cells which have intercellular spaces between them. the cell wall is made up of cellulose or calcium pectate. each cell has a prominent nucleus and a vacuolate cytoplasm. the cells are living and perform metabolic processes. there is a large central vacuole in each cell.