EFFECT OF MYCORRHIZAL INOCULATION ON YIELD AND DROUGHT TOLERANCE OF SOME FLAX VARIETIES.

Two field experiments were conducted at Ismailia Agric. Res. Station Farm, Ismailia Governorate, Egypt, in two successive seasons of 2004/05 and 2005/06, to study the influence of  vesicular - arbuscular (VA) mycorrhizal and sprinkler irrigation intervals (2,4 and 6 days) on the yield and yield components  as well as drought tolerance of the three flax genotypes viz., Sakha 2 (dual  type), S.2419/1/1 (oil type) and Viking (fiber type).
        Results indicated that, all characters under study were significantly affected by irrigation  intervals (Ir). Soil inoculation with VA mycorrhizal  fungi (M) significantly increased plant height, technical stem length, straw weight per plant, straw yield per fed, fiber yield per fed, number of capsules per plant, number of seeds per capsule, 1000-seed weight, seeds weight per plant, seed yield per fed, oil yield per fed, long fiber percentage, oil percentage compared with those un-inoculation. In contrast, soil inoculated with VA mycorrhizal fungi significantly decreased fiber fineness. 
         Sakha 2 gave the highest  means of straw weight per plant as well as straw yield per fed but, Viking ranked first for plant height, technical stem length and long fiber yield per fed while, S.2419/1/1 gave the highest means of capsules number per plant, 1000-seed weight, seeds weight per plant, seed and oil yields per fed when soil was inoculated with mycorrhizal and irrigated every / 2 or 4 days, without significant differences between them (2 and 4 days).
         Results revealed significant differences among flax varieties (V) in straw, seed yields and their components as well as quality characters. Also, all interactions between the studied factors were not significant except Irx M  for straw, seeds and oil yields per fed as well as  plant height, number of capsules per plant, 1000-seed weight, fiber fineness, and oil percentage as well as  M x V for fiber yield per fed in addition  Ir x M x V for plant height, technical stem length, number of capsules per plant, 1000-seed weight, fiber fineness, oil percentage as well as  straw,  fiber, seed and oil yields / fed.
          It can be concluded that under sandy soil condition its recommended to cultivate flax and inoculation with VA mycorrhizal fungi with irrigation at intervals of  2 or 4 days to obtain the highest straw yield, seeds yield and oil yield. This means that, soil inoculation by mycorrhizal fungi can increase the drought tolerance of flax plant from one irrigation / 2days to one irrigation / 4days.