توصيفگر ها :
تنش خشكي , كاج , همزيستي , قارچ اكتومايكوريزا , فضاي سبز , رنگدانههاي فتوسنتزي، , آنزيمهاي آنتي اكسيداني , نشانگرSRAP , نشانگر SCoT
چكيده انگليسي :
Therefore, this study aimed to investigate the effects of drought stress and the symbiosis with ectomycorrhizal (ECM)) fungi on the growth and physiological characteristics of some pine species during their juvenile stage in three separate experiments. The first study aimed to assess the genetic diversity among seedlings of pine species adapted to the Iranian climate (Pinus mugo, P. nigra, and P. brutia Ten var. eldarica) and two populations of native Canadian pine (P. banksiana) using SRAP and SCoT markers. The results showed that the samples were genetically divided into two distinct groups, with Iranian pine species in one category and two populations of P. banksiana in separate groups, indicating genetic differences among the samples that could potentially confer different levels of resistance to stresses or adaptability to different growth conditions in the propagated seedlings. In the second experiment, the effect of different levels of drought stress on several one-year pine species, a research in the form of a factorial experiment in the form of a completely randomized design (CRD) with two factors including five populations of four Tehran pine species (Pinus brutia Ten var. eldarica, P. nigra Arnold, P. mugo and P. banksiana Lamb (including populations 1 and 2), and three irrigation levels (100%, 75% and 50% FC) were done with three replications. Irrigation with 50% of field capacity significantly reduced the morphological, physiological traits, content of elements and appearance quality, but the percentage of ion leakage, proline, soluble carbohydrates, content of malondialdehyde, total phenol, activity of antioxidant enzymes increased. Irrigation based on 75% of the crop capacity compared to 100% of the crop capacity reduced the morphological and physiological traits, but compared to severe drought stress, the seedlings had acceptable quality. At the end of the second study, P. mugo and and P. brutia Ten var. eldarica species showed the highest drought tolerance and Banksiana species of population 8960049 showed the lowest tolerance. The third study was factorial in the form of a randomized complete block design with three factors including three species of pine (P. brutia Ten var. eldarica, P. mugo and P. banksiana Lamb population 8960049), three levels of drought stress (irrigation regime 100, 75, 50% of the crop capacity based on the weight and volume moisture method) and two levels of ectomycorrhizal fungus Sphaerosporella brunnea (inoculated or not inoculated with it) were implemented. Severe drought stress compared to irrigation treatment without drought stress significantly reduced height, fresh and dry weight of branches, root traits, photosynthetic pigments, relative content of leaf water, starch, protein, content of nutrients, symbiosis, ergosterol and appearance quality , but on the other hand, it increased the percentage of ion leakage, proline, soluble carbohydrates, content of malondialdehyde, total phenol, activity of antioxidant enzymes and hormone abscisic acid (ABA). The symbiosis with ectomycorrhizal fungus caused a significant increase in height traits, fresh and dry weight of branches, photosynthetic pigments, root traits, relative leaf water content, total phenol, nutritional elements, symbiosis, ergestrel, content of antioxidant enzyme activity, protein and appearance quality. Traits such as ion leakage, malondialdehyde content, proline, soluble carbohydrates, starch and abscisic acid hormone decreased in coexistence with ectomycorrhiza.
