Showing 3 results for Root Dry Weight
A Borzouei, S.s Jamali, F Paknejad,
Volume 5, Issue 4 (3-2015)
Abstract
In order to investigate the effects of irrigation water salinity on root traits and absorption of sodium (Na+) and potassium (K+) by wheat cultivars, a factorial experiment, based on completely randomized design with 3 replications, was conducted under greenhouse conditions. The main factor was 7 wheat genotypes ]Ghods, Marvdasht and Bahar (sensitive to salinity) and Arg, Bam, Sistani and Singh-2 (tolerant to salinity)] and the second factor was three levels of irrigation water salinity [1.3 (control), 5 and 10 dS/m]. In this study, the effect of salinity stress on root growth traits including root dry weight, root/shoot ratio, root volume and length, Na+/K+ ratio and grain yield were assessed. Results showed that increasing the salinity of irrigation water increased Na+/K+ ratio significantly, other studied traits were decreased significantly, and 10 dS/m salinity treatment caused the most negative effects. Means of the measured traits showed superiority of Arg, Bam, Sistani and Singh-2 cultivars, as compared to three other cultivars. Also, in all the studied traits, the highest percentage of reduction in 10 dS/m salinity, compared to control, was for Marvdasht cultivar, which shows the sensitivity of this genotype. Therefore, considerable superiority of some root characteristics and Na+/K+ ratio in salinity tolerant cultivars of wheat may be useful for screening the salinity tolerant wheat genotypes
H.r. Zekavati, M. Shoor, H. Rohani, F. Fazeli Kakhki, E. Ganji Moghadam,
Volume 10, Issue 3 (10-2019)
Abstract
In order to evaluate the effect of different Trichoderma isolates on reducing the effects of drought stress on Polianthes tuberose, two factorial experiments were carried out based on completely randomized design with three replications. The first factor in the first experiment was bi isolate, and in the second experiment was isolate 65 of Trichoderma harzianum, each at three levels (0, 10, 20% v/v) and the second factor was three levels of drought stress (25, 50, 100% of pot capacity). Results showed that both isolates increased fresh and dry weight of the biomass and root dry weight of Polianthes tuberose plant under stress conditions. The fresh weight of the biomass was increased by 20% in 25% stress by bi isolate and 29.5% by isolate 65, indicating that the growth of Polianthes tuberose in the presence of Trichoderma fungus increased. Proline content was increased by 40 and 32% by isolates bi and 65 in 25% stress compared to 100% pot capacity. The relative water content and leaf area were increased by applying different levels of the two fungi with increasing stress levels. The leaf area in the 25% stress and 20% fungus treatment were increased by 26 and 24%, respectively, in isolates bi and 65, compared to fungus-free pots. It seems that the isolates bi and 65 of Trichoderma harzianum have different effects under drought stress conditions. In terms of stress, 100% pot capacity and bi-isolate treatment, the root dry weight, fresh and dry weight of biomass, relative water content and leaf green area were more than the same traits in isolate 65 treatment.
E. Karimi, N. Alisgharzad, S. B. Mousavi, A. Aliloo,
Volume 13, Issue 2 (9-2022)
Abstract
Under water stress conditions, growth-promoting rhizobacteria could alter root characteristics, leading to increased plants yield. A controlled experiment with two barley cultivars, Dasht, and Kavir, was carried out with four inoculations of Bacillus simplex strains (31-2, 42-3, 51-4, and control), in two irrigation levels of 80 and 50% of field capacity. The results showed that inoculation with the mentioned bacteria increased the biological yield of barley by 28% under water stress condition compared to the control treatment. The effect of bacteria was cultivar dependent. B. simplex 31-2 had the most significant effect on the biological yield of Kavir cultivar, and B. simplex 42-3 on the Dasht cultivar. Linear relationships between root characteristics and barley's biological yield were observed. The highest coefficients of determination (R2) were obtained with fresh root weight (84%), root volume (83%), and root surface (81%). Considering the relationship between root traits and the biological yield of barley and the role of B. simplex 31-2 in a 121% increase in root area under water stress, it seems that this trait is the essential mediator of yield. Due to the insignificance effect of B. simplex 3-32 on the root characteristics, against the increase of shoot performance by this bacterium, its mode of action may be due to inducing improvement on other physiological pathways. Overall Bacillus bacteria are effective in mitigating the negative effect of water stress on barley and these bacteria can be considered effective candidates for the production of biofertilizers.
