Evaluation drought resistance of two species of Bromus (Bromus kopetdaghenis, Bromus tometolus) using mycorrhizal symbiosis

In order to study evaluation of resistance to dryness  in two species of Bromos by using micorhyza symbiosis, a test has been conducted in split split plot in the form of block basis plan fully randomly by four iterations  in two agricultural  years  of 1396_1397 and 1397-1398 in the south of Tehran  province. The main  court consisted of dryness tension in three levels: 1-control(without tension in field capacity limit)(s1), 2-average tension (60%  field capacity )( s2), 3-intensive tension (40% field capacity )(s3)and minor  court also consisted of using  micorhyza fungus in three levels including:1-without micorhyza as 1- control (M1), 2-the specie of Glomus intraradices (M2) 3- specie of  Glomus mosseae (M3), two species  of Bromus plant considered as minor court  in two levels including:1_ (B1)Bromus kopetdaghensis (B1) -and Bromus tometolus (B2).Results showed that dryness tension  resulted in decrease of  number of leaf . Productivity geometrical average  rate (MP) and productivity arithmetical average (MP)in the average tension  condition was higher than intensive tension. Using Micorhyza species (M2) resulted in significant increase of  the number of  leaf, grass qualityand productivity  arithmetical  average  index. In the  comparison of average (S×M), tension  and application of micorhyza resulted in increasing  root length and dry weight of entire plant.The most  dry weight of entire plant in (S3M2)resulted to the rate of 6/8 grams and  root length  in (S3M3)gained 7/37 cm.Application of (M2) in the third level resulted in  1/21 %of dry weight of entire plant toward lack of application of micorhyza in this tension rate.Also tension resulted in  decrease of grass quality and in every three levels of dry tension ,application of micorhyza  resulted in significant increase of grass quality toward control and this increase in (M2)was more than (M3).In this test the greatest root length gained in (S3B2).In the comparison between interaction average (M×B),the greatest  root length  gained in (M3B2)condition.Based on the result of  interaction average  comparison,(S×M×B),the highest height of plant gained in the treatment (S1M2B2).The greatest  GMP in both years in tometolus grass species gained  along with the application of G.intraradices micorhyza species (M2B2Y1) and (M2B2Y2). Based on results of interaction  (S×M×B×Y),the highest stand to dryness index gained (S3M2B2Y2) and (S3M2B2Y1).In general, the species  Bromus tometolus and using of fungus species  Glomus intraradices suggested for this region in dryness tension condition.