Determining plant resistance to salinity is very important for selecting the favorable plant species for saline rangelands. The objective of this study was to compare the salinity tolerance of three rangeland species (Agropyron elongatum, Kochia prostrata and Puccinellia distans). The experiment was conducted in a greenhouse, with a factorial arrangement in a completely randomized design using 5 replications. Salinity levels of 4 (as control), 20, 30 and 40 dS/m were applied. The results showed that increasing salinity level caused reduction in shoot height, shoot dry weight, root length, root weight and survival scores in all studied plant species. The maximum length and weight of the roots and the maximum height and weight of the shoot and the survival scores were found in the lowest salinity level (4 dS/m) treatment. However, the minimum length and weight of the roots and the minimum height and weight of the shoots and the survival scores were observed in the highest salinity level (40 dS/m) treatment. Among the studied species, Agropyron elongatum had the maximum and Kochia prostrata had the minimum salt tolerance.

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Studying the Effects of Salinity Stress on the Growth of Various Halophytic Plant Species (Agropyron elongatum, Kochia prostrata and Puccinellia distans)

Understory vegetation as an indicator of soil characteristics in the Hyrcanian area, N. Iran

Salinity is one of the most important agricultural issues causing considerable yield reduction in agricultural crops. The main adverse effects of salinity are due to excess amount of sodium ions that is toxic to plant cells. Most halophytes are equipped with defense mechanisms enabling them to tolerate the salty habitats. Among grass plants, Aeluropus littoralis is a known monocots halophyte that can tolerate harsh saline conditions. In this study, salt treatment was applied in three levels of 0, 200 and 400 mM NaCl after 45 days and biological samples were collected at 7, 14 and 21 days after treatment (DAT). For microscopic analysis, the tissues were cross-sectioned and stained using methylene blue for lignified tissues and Congo red for cellulosic tissues. The amounts of Na+ and K+ were measured by flame photometer and the content of lignin was measured by polymeric thioglycolic acid derivatives method. The results showed that the amount of Na+ increased 13-fold, while the stem length, stem diameter, vascular bundle number, metaxylem diameter, phloem diameter, K+, fresh weight and dry weight decreased significantly by 35%, 48%, 59%, 19%, 25%, 45%, 64% and 55% under salt treatment, respectively. The amount of lignin in stem did not significantly change under salinity. According to these results, A. littoralis can tolerate saline habitats by different adaptation strategies like the limitation of minerals transition and reduction of plant biomass. Furthermore, the concentration of lignin in metaxylem tissues and stele parenchyma led to increased resistance of halophytes in excess amounts of Na+.

http://www.jpmb-gabit.ir/article_27294_c9ddf362da8a85c792e333976969b16e.pdf

Morphological and anatomical changes in stems of Aeluropus littoralis under salt stress

3 Abstract: Determining plant resistance to salinity, aridity and grazing is very important for selecting the favorable plant species for rangelands. The objective of this study was to compare the salinity, aridity and grazing tolerance of three rangeland species (Agropyron elongatum, Kochia prostrata and Puccinellia distans). The experiment was conducted in a greenhouse, with a factorial arrangement in a completely randomized design using 3 replications. Salinity levels of 4 (as control), 20, 30 and 40 dS/m; Aridity levels of field capacity irrigation (as control), -12 and -14 bars; Grazing levels of 0% (as control), 25%, 50% and 75% cutting were applied. The results showed that increasing salinity and aridity level caused reduction in dry matter production and residual dry matter in all studied plant species. 25% cutting caused increment in residual dry matter. Increasing grazing level caused increment in dry matter production. The maximum survival scores were found in the lowest salinity, aridity and grazing level treatments. However, the minimum survival scores were observed in the highest salinity, aridity and grazing level treatments. Agropyron elongatum had the maximum and Kochia prostrata had the minimum salinity, aridity and grazing tolerance.

/pdf/studying-the-effects-of-salinity-aridity-and-grazing-stress-2kj5rjv701.pdf

Studying the Effects of Salinity, Aridity and Grazing Stress on the Growth of Various Halophytic Plant Species (Agropyron elongatum, Kochia prostrata and Puccinellia distans)

The study was accomplished in pure and mixed stands of Quercus castaneifolia and Quercus macranthera in northern Iran. collection of the sample and study of the ecological factors including the seasons, spring, summer and autumn of the years 2009 and 2010 was conducted and the scientific name of the species, life forms and Chorology were recorded using the available resources . 186 species have been identified of 6 Pteridophytes families, 2 families from Gymnosperms and 52 families of Angiosperms (8 families from a Dicotyledone and 44 families of Monocotyledon). The maximum number of species was related to the flowing family: Asteraceae, Papilionaceae, Lamiaceae, Orchidaceae and Poaceae. Raunkiaer’s classification of Hemicryptophytes 49%, Cryptophytes 20%, Phanerophytes 19%, and 8% Therophytes, Chamaephytes 3 percent and 1 percent of Epiphytic species are allocated to the region. Chorology study area showed the highest value in zone of EuropeSiberia (the Caspian), with 41% belonging. The study of the list of endangered species showed one endangered species, 5 vulnerable species. 20 species were identified as lower risk. Lilium ledebourii was identified as a rare species with relatively wide distribution in different parts of the region.

Biodiversity in oak forests (Quercus castaneifolia and Quercus macranthera) in Ramsar, northern Iran.

Investigation of the morphologic - physiologic changes of puccinelia distance and aeluropus littoralis to salinity and drought resistance

In order to obtain an optimum management of natural resources, determination of variables that control plant presence and distribution is needed. In the present research, the relationship between some character plants of drylands and some soil and environmental variables were investigated. After primary survey and selection of main plant species, sampling was done in each vegetation type within 3-4 transects (200 m length) by randomized-systematic method. Dominant species included Tamarix ramosissima , Salsola kali , Phragmites australis and Ephedra distachya . Vegetation sampling was done in 200 plots and soil sampling was done from two depth 0-20 and 20-60 cm in 38 plots. SHAZAM 10 package was used to find the logical relationship between plant species and environmental variables. The statistical pattern for this research was based on qualitative function. Therefore, logic function was evaluated. Results show that for T. ramosissima , potassium in the first depth and available water in the second depth; for S. kali , available water in the second depth; for P. australis , pH in the first depth and organic matter in the second depth, and for E. distachya , saturated moisture in the first depth and available water in the second depth have the most important role in plant presence and absence probability.

https://rostaniha.areeo.ac.ir/article_101489_1e0fb1216648ef0b731ae1756afcfa51.pdf

Habitat conditions and plant-environment relationship in some arid and semiarid lands character plants (case study: Shahriyar Rangelands, Tehran Province)

Jafari Mohammad

Papers

Investigation of the morphologic - physiologic changes of puccinelia distance and aeluropus littoralis to salinity and drought resistance

Habitat conditions and plant-environment relationship in some arid and semiarid lands character plants (case study: Shahriyar Rangelands, Tehran Province)

The effects of salinity stress on some of anatomical and morphological characteristics in three salsola species: s. rigida, s. dendroides, s. richteri