Antioxidant Compounds of Potato Breeding Genotypes and Commercial Cultivars with Yellow, Light Yellow, and White Flesh in Iran

Potatoes are a staple food with high antioxidant properties that can positively affect population health. The beneficial effects of potatoes have been attributed to tuber quality. However, the tuber quality related researches at genetic levels are very few. Sexual hybridization is a powerful strategy for producing new and valuable genotypes with high quality. In this study, 42 breeding potato genotypes in Iran were selected based on appearance characteristics such as shape, size, color, eyes of tubers, and tuber yield and marketability. The tubers were evaluated for their nutritional value and properties, viz. phenolic content, flavonoids, carotenoids, vitamins, sugars, proteins, and antioxidant activity. Potato tubers with white flesh and colored skin had significantly higher levels of ascorbic acid and total sugar. The result showed that higher phenolic, flavonoid, carotenoid, protein concentration, and antioxidant activity were noted in yellow-fleshed. Burren (yellow-fleshed) tubers had more antioxidant capacity in comparison to genotypes and cultivars, which did not differ significantly with genotypes 58, 68, 67 (light yellow), 26, 22, and 12 (white). The highest correlation coefficients in antioxidant compounds were related to total phenol content and FRAP, suggesting that phenolics might be crucial predictors of antioxidant activities. The concentration of antioxidant compounds in the breeding genotypes was higher than in some commercial cultivars, and higher antioxidant compounds content and activity were detected in yellow-fleshed cultivars. Based on current results, understanding the relationship between antioxidant compounds and the antioxidant activity of potatoes could be very helpful in potato breeding projects

Morphological and physiological responses of in vitro-grown cucurbita sp. landraces seedlings under osmotic stress by mannitol and PEG

Screening and identification of tolerant genotypes using osmotic materials under in vitro culture could be rapid, easy, and even accurate. In this research, three Iranian landraces of Cucurbita sp. included Tanbal Ajili (Cucurbita maxima Duch.), Ajili Razan (Cucurbita pepo L.), and Balghabakhi (Cucurbita moschata Duch.) seeds were cultured in 1/4 MS medium. After germination, plantlets were transferred to MS media containing mannitol and PEG 6000. Mannitol and PEG at three concentrations of 0.1, 0.2, and 0.4 M and 0.009, 0.012, and 0.015 M, respectively, were added into the MS medium, while the MS medium without any adding was used as control. Our findings revealed that osmotic treatments significantly increased shoot and root dry weight (DW), malondialdehyde (MDA), and proline content, but significantly reduced coleoptile length, shoot and root fresh weight, and photosynthesis pigments content. Protein content, phenols, and flavonoids content, enzymatic and non-enzymatic antioxidant including ascorbate peroxidase (APX), guaiacol peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) activity, reduced ascorbate (AsA), reduced ascorbate/dehydroascorbic acid (AsA/DHA), reduced glutathione (GSH), dehydroascorbic acid (DHA) and oxidized glutathione (GSSG), and reduced glutathione/oxidized glutathione (GSH/GSSG) were significantly increased at moderate osmotic stress induced by mannitol and PEG. In contrast, the previous physiological parameters were significantly reduced at higher water deficit conditions. With respect to most attributes and concentrations, mannitol simulated osmotic stress better than PEG. Our results revealed that applying PEG and mannitol under in vitro conditions could be an efficient way to evaluate and screen cucurbit genotypes for future breeding programs.IGA/FT/2022/004; University of MaraghehUniversity of Maragheh, Iran; [IGA/FT/2022/004

Polyethylene glycol and sorbitol-mediated in vitro screening for drought stress as an efficient and rapid tool to reach the tolerant cucumis melo l. genotypes

An efficient method to instantly assess drought-tolerant plants after germination is using osmoregulation in tissue culture media. In this study, the responses of three Iranian melon genotypes to sorbitol (0.1, 0.2, and 0.4 M) or polyethylene glycol (PEG) (0.009, 0.012, and 0.015 M) were evaluated as drought stress simulators in MS medium. 'Girke' (GIR), 'Ghobadloo' (GHO), and 'Toghermezi' (TOG) were the genotypes. GIR is reputed as a drought-tolerant genotype in Iran. The PEG or sorbitol decreased the coleoptile length, fresh weight, and photosynthetic pigments content while enhancing proline and malondialdehyde (MDA) contents. Protein content and antioxidant enzyme activity were utterly dependent on genotype, osmotic regulators, and their concentration. Coleoptile length, root and shoot fresh weight, root dry weight, proline and MDA content, and guaiacol peroxidase (GPX) activity can be used as indicators for in vitro screening of Cucumis melo L. genotypes. The results showed that sorbitol mimics drought stress better than PEG. Overall, our findings suggest that in vitro screening could be an accurate, rapid, and reliable methodology for evaluating and identifying drought-tolerant genotypes.IGA/FT/2023/003; University of MaraghehUniversity of Maragheh, Iran; TBU in Zlin [IGA/FT/2023/003

Chitosan–Selenium Nanoparticle (Cs–Se NP) Foliar Spray Alleviates Salt Stress in Bitter Melon

Salt stress severely reduces growth and yield of plants. Considering the positive effects of selenium (Se) and chitosan (Cs) separately against abiotic stress, in these experiments, we synthesized chitosan–selenium nanoparticles (Cs–Se NPs) and investigated their ability to reduce the negative effects of salt stress on growth and some biochemical parameters of bitter melon (Momordica charantia). Bitter melon plants were grown at three NaCl salinity levels (0, 50, and 100 mM) and a foliar spray of Cs–Se NPs (0, 10, and 20 mg L−1) was applied. Some key morphological, biochemical, and physiological parameters in leaf samples and essential oil from fruit were measured at harvest. Salinity decreased growth and yield while foliar application of Cs–Se NPs increased these critical parameters. Furthermore, Cs–Se NPs enhanced bitter melon tolerance to salinity by increasing antioxidant enzyme activity, proline concentration, relative water content, and K+, and decreasing MDA and H2O2 oxidants and Na aggregation in plant tissues. Yield was also improved, as the highest amount of essential oils was produced by plants treated with Cs–Se NPs. Generally, the greatest improvement in measured parameters under saline conditions was obtained by treating plants with 20 mg L−1 Cs–Se NPs, which significantly increased salinity tolerance in bitter melon plants

Morphological and Physiological Responses of In Vitro-Grown Cucurbita sp. Landraces Seedlings under Osmotic Stress by Mannitol and PEG

Screening and identification of tolerant genotypes using osmotic materials under in vitro culture could be rapid, easy, and even accurate. In this research, three Iranian landraces of Cucurbita sp. included Tanbal Ajili (Cucurbita maxima Duch.), Ajili Razan (Cucurbita pepo L.), and Balghabakhi (Cucurbita moschata Duch.) seeds were cultured in ¼ MS medium. After germination, plantlets were transferred to MS media containing mannitol and PEG 6000. Mannitol and PEG at three concentrations of 0.1, 0.2, and 0.4 M and 0.009, 0.012, and 0.015 M, respectively, were added into the MS medium, while the MS medium without any adding was used as control. Our findings revealed that osmotic treatments significantly increased shoot and root dry weight (DW), malondialdehyde (MDA), and proline content, but significantly reduced coleoptile length, shoot and root fresh weight, and photosynthesis pigments content. Protein content, phenols, and flavonoids content, enzymatic and non-enzymatic antioxidant including ascorbate peroxidase (APX), guaiacol peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) activity, reduced ascorbate (AsA), reduced ascorbate/dehydroascorbic acid (AsA/DHA), reduced glutathione (GSH), dehydroascorbic acid (DHA) and oxidized glutathione (GSSG), and reduced glutathione/oxidized glutathione (GSH/GSSG) were significantly increased at moderate osmotic stress induced by mannitol and PEG. In contrast, the previous physiological parameters were significantly reduced at higher water deficit conditions. With respect to most attributes and concentrations, mannitol simulated osmotic stress better than PEG. Our results revealed that applying PEG and mannitol under in vitro conditions could be an efficient way to evaluate and screen cucurbit genotypes for future breeding programs

Morphological and Physiological Responses of In Vitro-Grown <i>Cucurbita</i> sp. Landraces Seedlings under Osmotic Stress by Mannitol and PEG

Screening and identification of tolerant genotypes using osmotic materials under in vitro culture could be rapid, easy, and even accurate. In this research, three Iranian landraces of Cucurbita sp. included Tanbal Ajili (Cucurbita maxima Duch.), Ajili Razan (Cucurbita pepo L.), and Balghabakhi (Cucurbita moschata Duch.) seeds were cultured in ¼ MS medium. After germination, plantlets were transferred to MS media containing mannitol and PEG 6000. Mannitol and PEG at three concentrations of 0.1, 0.2, and 0.4 M and 0.009, 0.012, and 0.015 M, respectively, were added into the MS medium, while the MS medium without any adding was used as control. Our findings revealed that osmotic treatments significantly increased shoot and root dry weight (DW), malondialdehyde (MDA), and proline content, but significantly reduced coleoptile length, shoot and root fresh weight, and photosynthesis pigments content. Protein content, phenols, and flavonoids content, enzymatic and non-enzymatic antioxidant including ascorbate peroxidase (APX), guaiacol peroxidase (GPX), superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) activity, reduced ascorbate (AsA), reduced ascorbate/dehydroascorbic acid (AsA/DHA), reduced glutathione (GSH), dehydroascorbic acid (DHA) and oxidized glutathione (GSSG), and reduced glutathione/oxidized glutathione (GSH/GSSG) were significantly increased at moderate osmotic stress induced by mannitol and PEG. In contrast, the previous physiological parameters were significantly reduced at higher water deficit conditions. With respect to most attributes and concentrations, mannitol simulated osmotic stress better than PEG. Our results revealed that applying PEG and mannitol under in vitro conditions could be an efficient way to evaluate and screen cucurbit genotypes for future breeding programs

Polyethylene Glycol and Sorbitol-Mediated In Vitro Screening for Drought Stress as an Efficient and Rapid Tool to Reach the Tolerant <i>Cucumis melo</i> L. Genotypes

An efficient method to instantly assess drought-tolerant plants after germination is using osmoregulation in tissue culture media. In this study, the responses of three Iranian melon genotypes to sorbitol (0.1, 0.2, and 0.4 M) or polyethylene glycol (PEG) (0.009, 0.012, and 0.015 M) were evaluated as drought stress simulators in MS medium. ‘Girke’ (GIR), ‘Ghobadloo’ (GHO), and ‘Toghermezi’ (TOG) were the genotypes. GIR is reputed as a drought-tolerant genotype in Iran. The PEG or sorbitol decreased the coleoptile length, fresh weight, and photosynthetic pigments content while enhancing proline and malondialdehyde (MDA) contents. Protein content and antioxidant enzyme activity were utterly dependent on genotype, osmotic regulators, and their concentration. Coleoptile length, root and shoot fresh weight, root dry weight, proline and MDA content, and guaiacol peroxidase (GPX) activity can be used as indicators for in vitro screening of Cucumis melo L. genotypes. The results showed that sorbitol mimics drought stress better than PEG. Overall, our findings suggest that in vitro screening could be an accurate, rapid, and reliable methodology for evaluating and identifying drought-tolerant genotypes

Effect of melatonin foliar sprays on morphophysiological attributes, fruit yield and quality of Momordica charantia L. under salinity stress

: Soil salinity is one of the increasing problems in agricultural fields in many parts of the world, adversely affecting the performance and health of the plants. As a pleiotropic signal and antioxidant molecule in both animals and plants, melatonin has been reported to possess significant roles in combating with stress factors, in general and salt stress, in particular. In this study, the interactive effects of melatonin (0, 75, and 150&nbsp;μM) and salt stress (0, 50 and 100&nbsp;mM NaCl) were investigated by assaying the some agronomic, physlogical and biochemical attributes and essential oil compounds of bitter melon (Momordica charantia). The results showed that exogenous melatonin could promote net photosynthetic rate (Pn) and PSII efficiency (Fv/Fm), increase K+ content and activity of antioxidant enzymes and decrease reactive oxygen species, malondialdehyde and Na+ content in stress-submitted seedlings, in comparison to the non-stressed seedlings (p&nbsp;&lt;&nbsp;0.05). Melatonin increased content of essential oils. Concerning the major compounds of fruits of bitter melon, charantin, momordicin and cucurbitacin were increased with the melatonin treatments, whereas they were critically decreased with the salt stress. In addition, melatonin increased the antioxidant capacity in fruits under non-saline and salinity conditions. Amid the concentrations of melatonin, plants treated with 150&nbsp;μM of melatonin under either non-saline or saline conditions showed better performance and productivity. Therefore, application of 150&nbsp;μM melatonin resulted in a significant improvement of salinity tolerance and essential oil compounds in bitter melon plant, suggesting this as an efficient 'green' strategy for sustainable crop production under salt stress conditions