This study aimed to investigate and compare the effects of exogenous glycinebetaine (GB) and trehalose (TR) on the biological responses of duckweed (Lemna gibba L.) against cadmium (Cd) accumulation. Duckweed samples were exposed to 0.5, 1, and 3 mM of Cd for 6 days in the presence and absence of GB (0.5, 1, 2, and 5 mM) or TR (0.5, 1, 2, and 5 mM). The accumulation of Cd, GB, and TR were investigated, and their influence on the rates of lipid peroxidation, photosynthetic activity, proline content and enzymatic antioxidant performance was examined. Two-way ANOVA showed that exposure to Cd and/or GB or TR caused an increase in Cd accumulation concentration dependently. TR had significant effects on Cd accumulation. The application of 0.5 mM TR increased Cd accumulation, whereas 5 mM decreased Cd accumulation. However, Cd accumulation was not significantly affected by the presence of GB. Cd concentration alone or in combination with GB or TR had a significant effect on lipid peroxidation, photosynthetic activity, proline content, and antioxidant enzyme activities. In addition, statistically significant GB-Cd and TR-Cd interactions were observed. We conclude that both GB and TR play protective roles against Cd stress in aquatic plants. The use of a low level of TR (i.e., 0.5 mM) may be more useful than GB in phytoremediation studies.

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This study is conducted to characterize some nutritional attributes and starch properties of 156 Turkish sorghum populations and 4 standard cultivars (Sorghum bicolor L.). Crude protein contents of the populations vary between 6.67% and 14.33%, digestible protein ratios between 6.67% and 82.24%, crude oil contents between 2.15% and 6.40%, phytic acid contents between 0.37% and 4.09%, resistant starch between 1.10% and 34.23%, nonresistant starch between 10.79% and 79.61%, total starch between 15.42% and 85.54%, amylose between 5.67% and 43.48%, amylopectin between 9.45% and 65.67%, total phenolic between 0.19% and 5.06 mg GAE/g and antiradical activity between 3.72% and 91.48%. Significant differences are obtained from starch‐based Rapid Visco Analyzer parameters of sorghum genotypes. As compared standard cultivars, several superior genotypes are identified in terms of nutritional characteristics. Genotype treatment (GT) biplot analysis revealed ideal genotypes for investigated parameters. Present findings confirmed that there are many genotypes with superior nutritional properties in local sorghum genotypes.

To assess its response to the herbicide, tribenuron-methyl, samples of Nasturtium officinale were exposed to 0, 0.01, 0.05, 0.1, and 0.5 mg L -1 of tribenuron-methyl for 1, 2, 4 and 7 days.The influence of this herbicide on the relative growth rate, electrolyte leakage, lipid peroxidation, photosynthetic pigmentation, protein content, and performance of anti-oxidant enzymes, such as superoxide dismutase (SOD), catalase, and ascorbate peroxidase (APX), was examined.The results indicated that tribenuron-methyl, applied at 0.5 mg L -1 , affected plant growth negatively. It also was determined that chlorophyll a is the most responsive photosynthetic pigment to tribenuron-methyl exposure. Under stress conditions, the anti-oxidant enzymes were up-regulated compared to the control.The SOD activity was significantly stimulated, while the activity of APX was inhibited. A significant correlation was found between lipid peroxidation and SOD activity.The exposure period and herbicide concentration had significant effects on the biological responses against tribenuron-methyl stress. These results may be useful for clarifying the effect of herbicides on non-target aquatic plants.

Bacillus spp. can promote the growth of plants and reduce plant disease incidence or severity by triggering induced systemic resistance to plant pathogens. In addition, bacteria of this genus are chitinase enzyme producers. Chitinase inhibits the growth of fungi by breaking down the chitin-containing cell wall of plant pathogenic fungi. In this study, 270 native Bacillus spp., isolated from various habitats in Kayseri and Adana, Turkey, were screened by PCR for the chitinase gene and 66 of them were found to have this gene. Nine Bacillus thuringiensis (Bt) isolates showing high insecticidal activity against insect pests in our previous studies were selected from 66 isolates containing the chitinase gene. Chitinases with different molecular weights ranging from 40 to 113 kDa were determined by SDS-PAGE. To determine the antagonistic effects against plant pathogenic fungi (Fusarium oxysporum f.sp. niveum, Verticillium dahliae and Aspergillus niger), a dual culture assay was used with nine native and two standard strains of Bt, and radial growth inhibition was calculated as a percentage. Of all the tested isolates, SY33.3 showed the strongest antagonistic activity and thus, can be used as an effective biological control agent against plant pathogenic fungi.

Objective:Sorghum has received great interest for resistance to heavy metals. Therefore, effects of Aluminum (Al), Chromium (Cr) and Lead (Pb) concentrations (2, 4, 8, 16, 32 and 64 ppm) on antioxidant enzyme systems of Sorghum in root and leaf tissues were investigated.Methods:Seeds were cultivated in hydroponic Hoagland solution containing heavy metal concentrations in a growth chamber. Malondialdehyde (MDA), proline levels, catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) and glutathione S-transferase (GST) activities were evaluated after treatment.Results:Al doses decreased chlorophyll a (Chl a) at 4 ppm and subsequent doses, and total Chl at 32 and 64 ppm doses, however, it did not cause any change at Chl b except at 2 ppm. Although 64 ppm of Al, Cr, and Pb decreased total Chl, it increased proline level (nearly 5, 21 and 40 times higher compared to control, respectively) in leaf. Common observation is that positive correlation was apparent between proline, MDA, APX and GST activity for Al and Cr treatments and GST activity for three elements in root. Also, the only positive correlation was evident between proline and MDA for Al and Cr applications in leaf.Conclusion:Although sorghum is resistant to heavy metals, induction of antioxidant enzymes seem to be not enough at higher concentrations to protect cells from heavy metal toxicity; however, it has great importance for further studies to find out whether phenolic compounds produced in sorghum have additive role in this regard.

In this study, the cry1Ab gene of previously characterized and Lepidoptera-, Diptera-, and Coleoptera-active Bacillus thuringiensis SY49-1 strain was cloned, expressed and individually tested on Ephestia kuehniella (Lepidoptera: Pyralidae) and Plodia interpunctella (Lepidoptera: Pyralidae) larvae. pET-cry1Ab plasmids were constructed by ligating the cry1Ab into pET28a (+) expression vector. Constructed plasmids were transferred to an Escherichia coli BL21 (DE3) strain rendered competent with CaCl2. Isopropyl β-d-1-thiogalactopyranoside was used to induce the expression of cry1Ab in E. coli BL21(DE3), and consequently, ∼130 kDa of Cry1Ab was obtained. Bioassay results indicated that recombinant Cry1Ab at a dose of 1000 μg g−1 caused 40% and 64% mortality on P. interpunctella and E. kuehniella larvae, respectively. However, the mortality rates of Bt SY49-1 strains’ spore–crystal mixture at the same dose were observed to be 70% on P. interpunctella and 90% on E. kuehniella larvae. The results indicated that cry1Ab may be considered as a good candidate in transgenic crop production and as an alternative biocontrol agent in controlling stored product moths.

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