Abstract: For the study of salinity stress on Vicia villosa and calcium effect for modulation of that, an experiment was conducted under hydroponic condition, and some important morphological and physiological characteristics were evaluated. This experiment was conducted as a factorial based on randomized complete design with three replications. The treatments include salinity stress in three levels (0, 50, and 100 mM NaCl) and calcium in two levels (content in Hoagland solution and double content). The results showed that all morphological and physiological traits include root and shoot length, root and shoot wet and dry weight, leaf area, leaf chlorophyll content, RWC, CMS, and biological yield was significantly different from the control and is affected by the salinity stress severely. But, calcium effect on them was not significant despite of decreasing salinity effect.
Abstract: Salinity is one of the major factors limiting crop
production in an arid environment. Despite its global importance
soybean production suffer the problems of salinity stress causing
damages at plant development. So it is implacable to either search for
salinity enhancement of soybean plants. Therefore, in the current
study we try to clarify the mechanism that might be involved in the
ameliorating effects of osmo-protectants such as proline and glycine
betaine as well as, compost application on soybean plants grown
under salinity stress. The experiment was conducted under
greenhouse conditions at the Graduate School of Biosphere Science
Laboratory of Hiroshima University, Japan in 2011. The experiment
was designed as a spilt-split plot based on randomized complete
block design with four replications. The treatments could be
summarized as follows; (i) salinity concentrations (0 and 15 mM), (ii)
compost treatments (0 and 24 t ha-1) and (iii) the exogenous, proline
and glycine betaine concentrations (0 mM and 25 mM) for each.
Results indicated that salinity stress induced reduction in growth and
physiological aspects (dry weight per plant, chlorophyll content, N
and K+ content) of soybean plant compared with those of the
unstressed plants. On the other hand, salinity stress led to increases in
the electrolyte leakage ratio, Na and proline contents. Special
attention was paid to, the tolerance against salt stress was observed,
the improvement of salt tolerance resulted from proline, glycine
betaine and compost were accompanied with improved K+, and
proline accumulation. While, significantly decreased electrolyte
leakage ratio and Na+ content. These results clearly demonstrate that
harmful effect of salinity could reduce on growth aspects of soybean.
Consequently, exogenous osmoprotectants combine with compost
will effectively solve seasonal salinity stress problem and are a good
strategy to increase salinity resistance of soybean in the drylands.
Abstract: The effect of exogenous application; seed priming or foliar spraying of salicylic acid (SA) on Yecora Rojo and Paragon wheat cv. under NaCl-salinity. Gas exchange parameters, growth parameters, yield and yield components were reduced in both cultivars under salinity stress with foliar spray and soaking seeds. Exogenous application of SA through foliar spraying or seed soaking showed a slight increases or decreases with the application method or between cultivars. SA foliar spraying exhibited a slight improvement over SA seed soaking in most parameters, particularly in Paragon. Although, seed soaking was less effective than foliar spraying, it was a slightly better with Yecora Rojo in some parameters. However, the low SA concentration; 0.5mM tended to improve most parameters in both cultivars. From data of the experiment, it has been concluded that the effect of SA depends on cultivar genotype and SA concentration.
Abstract: Evaluation of crop plants resistance to environmental
stresses specially in germination stage is a critical factor in their
selection in different conditions of cultivation. Therefore use of a
procedure in controllable situation can help to evaluate plants
reaction to stress quickly and precisely. In order to study germination
characteristics of flax in water and salinity stress conditions were
conducted two laboratories experimental. The two experimental were
conducted in 4-replicant completing random design for salinity and
water stress. The treatment, for salinity and water stress was three
potential (zero, 40, 80 mM) of NaCl and three potential (zero, -2, -4
bar) of PEG respectively. Germination percentage and rate, in
addition to Radical and plumule length and dry-weight and
plumule/Radical ration were measured. All of characteristics reduce
under water stress conditions. salinity stress significant reduce
germination rate and Radical and plumule length of flax seeds.
Hydropriming and osmopriming significant increased germination
rate, plumule length and plumule/Radical ration ration of flax seeds.
But germination percentage and Radical and plumule dry weight
significant increased only in hydropriming treat. Hydropriming and
osmopriming could not be used to improved germination under saline
and drought stress. But has more tolerance in salinity and drought
stress in flax by less reduce in Radical and plumule length under
saline and drought stress.
Abstract: An experiment was implemented in a filed in the south of Morocco to evaluate the effects of domestic treated wastewater use for irrigation of amaranth crop under semi-arid conditions. Three varieties (A0020, A0057 & A211) were tested and irrigated using domestic treated wastewater EC1 (0,92 dS/m) as control, EC3 (3dS/m) and EC6 (6dS/m) obtained by adding sea water. In term of growth, an increase of the EC level of applied irrigation water reduced significantly the plant-s height, leaf area, fresh and dry weight measured at vegetative, flowering and maturity stage for all varieties. Even with the application of the EC6, yields were relatively higher in comparison with the once obtained in normal cultivation conditions. A significant accumulation of nitrate, chloride and sodium in soil layers during the crop cycle was noted. The use of treated waste water for its irrigation is proved to be possible. The variety A211 had showed to be less sensitive to salinity stress and it could be more promising its introduction to study area.
Abstract: The heterotrophic seedling growth can be defined as a
product of two components: (1) the weight of mobilized seed reserve,
and (2) conversion efficiency of utilized seed reserve to seedling
tissue. The first component can be further divided into (1) initial seed
weight, and (2) the fraction of seed reserve, which is mobilized. The
objective of this study was the identification of the sensitive seedling
growth component(s) in response to drought and salinity stresses.
Two experiments were separately conducted using various salinity
levels (osmotic pressure) of 0, 0.25, 0.50, 0.75, 1, 1.25 and 1.5 MPa
created using NaCl as first experiment and by polyethylene glycol
(drought stress) of 0, 0.2, 0.4, 0.6, 0.8, 1, 1.2 and 1.4 MPa in second
experiment. Seeds of five crops species (Hordeum vulgare, Brassica
napus, Zea mays, Medicago sativa and Medicago scutellata) were
used in each experiment. In both experiments, seedling growth,
fraction of seed reserve utilization and weight of mobilized seed
reserve decreased with increasing drought and salt intensity.
However, drought and salinity stresses had no effect on the
conversion efficiency. It was concluded that the sensitive component
of seedling growth is the weight of mobilized seed reserve.