The current study was aimed to examine the effects of two types of Arbuscular mycorrhizal Fungi (F. mosseae, C. etunicatum) on the onion plant under two water conditions (normal irrigation and drought treatment). This study has aspects related to improve tolerance of an onion plant (Allium cepa L.) to water stress situations with taking in consideration regulate physiological Growth Parameters PGP of plant and biochemical [fungal root colonization, dry weight of mycorrhizal roots, Spore density of AM fungi, Relative water content, proline content, total carotenoids, Soluble protein content and Phosphorous application] in the existence or lack of AMF. The results indicate that the drought dealing producing increase of spore density of AM fungi, proline content, total carotenoids and soluble protein content except Fugal root colonization, plant root dry weight, Relative water content and Phosphorous uptake which were increased when associating with normal irrigation. The plants inoculated by each F. mosseae, C. etunicatum was noted a significant differences (P < 0.05) increase in some PGP comparing with uninoculated. The highest values of PGP were recorded when onion plant inoculated by two types of AMF. Normal irrigation was showed less enhancement of plants compared with plants that obtained drought stress. The inoculcation by both types of AMF resulted in increasing in an onion plant uptake and protection against drought stress, while the case of relative water content showed relatively similar values in both conditions comparing with non- AMF onion plant.
In order to serve the field of knowledge in the field of design and analysis of experiments by adopting formulas and methods that are easy and simple in arithmetic work, especially in experiments that require many calculations for squares, including tests of type
