Comparing Salt Tolerance at Seedling and Germination Stages in Local Populations of Medicago ciliaris L. to Medicago intertexta L. and Medicago scutellata L.

Salt stress is one of the most serious environmental stressors that affect productivity of salt-sensitive crops. Medicago ciliaris is an annual legume whose adaptation to agroclimatic conditions has not been well described. This study focused on the salinity tolerance of M. ciliaris genotypes compared to M. intertexta and M. scutellata in terms of plant growth, physiology, and biochemistry. Salt tolerance was determined at both germination and early seedling growth. Germination and hydroponic assays were used with exposing seeds to 0, 50, 100, 150, and 200 mM NaCl. Among seven genotypes of M. ciliaris studied, Pop1, 355, and 667, were most salt tolerant. Populations like 355 and 667 showed marked tolerance to salinity at both germination and seedling stages (TI ≤1, SI(FGP) > 0 increased FGP ≥ 20% and SI(DW) < 0 (DW decline ≤ 20%); at 100 mM); while Pop1 was the most salt tolerant one at seedling stages with (TI =1.79, SI(FGP) < 0 decline of FGP ≤ 40% and with increased DW to 79%); at 150 mM NaCl). The genotypes, 306, 773, and M. scutellata, were moderately tolerant to salt stress depending on salt concentration. Our study may be used as an efficient strategy to reveal genetic variation in response to salt stress. This approach allows selection for desirable traits, enabling more efficient applications in breeding methods to achieve stress-tolerant M. ciliaris populations.

Feasibility Study on Reducing Lead and Cadmium Absorption by Alfalfa (Medicago scutellata L.) in a Contaminated Soil Using Nano-Activated Carbon and Natural Based Nano-Zeolite

The first risk posed by heavy metal pollution in an ecosystem is metal accumulation in the biomass of growing plants, which has harmful effects on human health. Natural-based nanoparticles are efficient in remediating environmental pollutants because they have a high surface/volume ratio, high chemical activity and produce no harmful side-products. The present study investigates the capacity of natural-based nano-porous adsorbents for reducing the availability of heavy metals to annual alfalfa (Medicago scutellata L.) roots and keeps them in soil. In a factorial experiment based on a randomized design (with four replications), three nano-adsorbents (nano-activated carbon, natural nano-zeolite and modified nano-zeolite) and two heavy metals (lead and cadmium) have been tested. The results demonstrated that applying the highest rate of activated carbon and modified nano-zeolite reduced shoot Pb content by 34% and 33.2%, and shoot Cd content by 35.5% and 46.7%, respectively, compared with the adsorbent-free control. ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Effect of seed coating on germination of Ciliate Medick [Medicago ciliaris (L.) All.] and Snail Medick [Medicago scutellata (L.) Mill.]

A study was conducted in the Seed Technology Laboratory of Department of Field Crops, Pasture and Forage Crops Section, Faculty of Agriculture of Ege University, Turkey. Aim of the study was to remove the seed coat hardness by various treatments of Ciliate and Snail Medick to enhance germination which is significant in terms of agronomical handicaps of sowing small seeded legumes under field conditions. Pre-sowing seed treatments (Control, scarification by sandpaper, acid treatment with 95.0-98.0% H2SO4 for 5-10-15 minutes and soaking in water for 24-48 hours) were practiced on these small seeded legumes. All observations and tests were conducted following ISTA regulations and notifications. Germination of tested seeds highly increased by acid treatment for 10-15 minutes duration, while scarification treatment provided favorable germination rates.

Effect of different fertilizing and farming systems in annual medic (Medicago scutellata ’Robinson’) on soil organic matter and nutrients status

<p>This experiment was conducted to study the effect of different fertilizing and farming systems in annual medic (<em>Medicago scutellata</em> ‘Robinson’) on soil organic matter and nutrients status. Fertilizing systems consisted of control (no fertilizer), chemical fertilizer, biological fertilizer and integrated fertilizers (different combinations of chemical and biological fertilizing systems). The farming systems included irrigated and dry-farming systems. The experiment was conducted in two experimental sites with diverse climatic and soil conditions in Kermanshah province, Iran, during 2009 growing season. The highest amount of soil organic matter of 1.28 % was observed in integrated fertilizing system of nitrogen-fixing bacteria + phosphorus-solubilizing bacteria. Most of the nitrogen applied through chemical fertilizers was leached out of the plant access, however, application of integrated fertilizer resulted in increasing the concentration of nitrogen in soil because of its slow release and efficient utilization by plants. According to the results of this study it was concluded that the integrated fertilizing system was more successful in dry farming compared to other fertilizing systems.</p>