Comparative analysis of antioxidant potential in leaf, stem, and root of Paederia foetida L.

Paederia foetida L. is widely used for the treatment of myriad ailments. Thus, searching for plant parts having greater antioxidant potential would make it easy to get suitable materials for herbal drugs. The present effort was made to explore the antioxidant potentials in the plant parts of P. foetida grown under natural conditions by means of physiological and biochemical analyses. The young leaves showed the highest reservoir of non-enzymatic antioxidants such as chlorophylls (0.96 mg g-1), carotenoids (0.43 mg g-1), anthocyanins (53.99 µg g-1), phenolics (728.24 µg g-1), flavonoids (4178.05 µg g-1), and proline (1.46 µmol g-1) as compared to others. Total antioxidant activity was found to be the highest in young leaves (84.82 %) followed by young stems (80.24 %) and matured leaves (79.78 %). Analysis of enzymatic antioxidants resulted in the superior activity of ascorbate peroxidase (13.58 µmol min-1 mg-1) and glutathione S-transferase (3409 nmol min-1 mg-1) in young leaves whereas the highest rate of catalase (409.85 µmol min-1 mg-1) and peroxidase (3.5 nmol min-1 mg-1) activity were found in matured leaves. However, comparatively higher content of reactive oxygen species; hydrogen peroxide, and lipid peroxidation product; malondialdehyde in matured leaves than that of young leaves suggests that young leaf is a suitable source for herbal medicine

A 7×7 diallel cross for developing high-yielding and saline-tolerant barley (Hordeum vulgare L.)

In this experiment, F1s produced from a 7 × 7 half-diallel cross along with their parents were evaluated to develop high yielding and saline-tolerant barley lines. The investigation focused on the general combining ability (GCA) of parents, specific combining ability (SCA) of offspring, genetic action, and heterosis of eight quantitative variables. Genetic analysis and potence ratio suggested that different degrees of dominance controlling the inheritance of the studied traits. Significant GCA and SCA variances suggested the presence of both additive and non-additive gene actions controlling the traits. However, a GCA:SCA ratio lower than 1 indicated the preponderance of the non-additive gene action involved in the expression of the traits. The parents P5 and P6 possess the genetic potential favorable for early and short stature in their F1s. Conversely, P2 and P4 were more likely to produce short F1s with high yield potential. Based on the mean performance, SCA, and heterobeltiosis, crosses P2 × P3, P2 × P7, P3 × P4, P4 × P5, P5 × P6, and P6 × P7 were selected as promising F1s for earliness, short stature, and high yield potential. These crosses are recommended for further breeding to obtain early-maturing and high-yielding segregants. To identify saline-tolerant F1s, screening was conducted in saline media prepared in half-strength Hoagland solution. The salinity stress involved exposing F1s to 100 mM NaCl for first 10 days, and followed by an increase to 150 mM until maturity. Among the F1s, five crosses (P1 × P2, P2 × P3, P3 × P5, P4 × P6, and P4 × P7) exhibited promising signs of saline tolerance based on a comprehensive evaluation of healthy seed set, K+/Na+ ratio, root volume, generation of reactive oxygen species (O2•− and H2O2), and activities of key antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR). These crosses will undergo further evaluation in the next filial generation to confirm heritable saline tolerance

Variation of Wheat Cultivars in Their Response to Elevated Temperature on Starch and Dry Matter Accumulation in Grain

Three wheat cultivars, namely, BARI Gom 25, BARI Gom 26, and Pavon 76, were sown in experimental field of Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, in Bangladesh, on 18 November, 2013. Two temperature regimes, namely, normal (23°C in open field) and elevated (6 ± 1°C higher compared to open field mean air temperature in polythene chamber) temperature, were created immediately after anthesis to investigate the response of wheat cultivars to heat stress. Elevated temperature cuts back the duration of grain filling by 5 days in BARI Gom 25 and BARI Gom 26 and 10 days in Pavon 76. Starch synthesis was also cut back by the same duration in respective cultivars under elevated temperature condition. Results indicate that failure of conversion of sugar to starch rather than limited supply of sugar under high temperature condition was responsible for shortening of grain filling duration in all wheat cultivars. However, the response of elevated temperature on grain starch and main stem grain dry matter was less profound in BARI Gom 25 and BARI Gom 26 compared to Pavon 76 indicating their better tolerance to elevated temperature

NADPH oxidase-mediated reactive oxygen species, antioxidant isozymes, and redox homeostasis regulate salt sensitivity in maize genotypes

The aim of the study is to examine the relationship between oxidative bursts, their regulation with ion homeostasis, and NADPH oxidase (NOX) in different salt-sensitive maize genotypes. For this, in the first study, four differently salt-sensitive maize genotypes (BIL214 × BIL218 as tolerant, BHM-5 as sensitive, and BHM-7 and BHM-9 as moderate-tolerant) were selected on the basis of phenotype, histochemical detection of reactive oxygen species (ROS), malondialdehyde (MDA) content, and specific and in-gel activity of NOX. In the next experiment, these genotypes were further examined in 200 mM NaCl solution in half-strength Hoagland media for nine days to study salt-induced changes in NOX activity, ROS accumulation, ion and redox homeostasis, the activity of antioxidants and their isozyme responses, and to find out potential relationships among the traits. Methylglyoxal (MG) and glyoxalse enzymes (Gly I and II) were also evaluated. Fully expanded leaf samplings were collected at 0 (control), 3, 6, 9-day, and after 7 days of recovery to assay different parameters. Na+/K+, NOX, ROS, and MDA contents increased significantly with the progression of stress duration in all maize genotypes, with a significantly higher value in BHM-5 as compared to tolerant and moderate-tolerant genotypes. A continual induction of Cu/Zn-SOD was observed in BIL214 × BIL218 due to salt stress. Substantial decreases in CAT2 and CAT3 isozymes in BHM-5 might be critical for the highest H2O2 burst in that sensitive genotype under salt stress. The highest intensified POD isozymes were visualized in BHM-5, BHM-7, and BHM-9, whereas BIL214 × BIL218 showed a continual induction of POD isozymes, although GPX activity decreased in all the genotypes at 9 days. Under salt stress, the tolerant genotype BIL214 × BIL218 showed superior ASA- and GSH-redox homeostasis by keeping GR and MDHAR activity high. This genotype also had a stronger MG detoxification system by having higher glyoxalase activity. Correlation, comparative heatmap, and PCA analyses revealed positive correlations among Na+/K+, NOX, O2•−, H2O2, MG, proline, GR, GST, and Gly I activities. Importantly, the relationship depends on the salt sensitivity of the genotypes. The reduced CAT activity as well as redox homeostasis were critical to the survival of the sensitive genotype

Assessment of Genetic Diversity of Bread Wheat Genotypes for Drought Tolerance Using Canopy Reflectance-Based Phenotyping and SSR Marker-Based Genotyping

This study investigated the genetic diversity of bread-wheat genotypes using canopy reflectance-based vegetation indices (VIs) and simple sequence repeat (SSR) marker-based genotyping for drought tolerance. A total of 56 wheat genotypes were assessed using phenotypic traits (combination of VIs and yield traits) and 30 SSR markers. The data of the phenotypic traits were averaged over two growing seasons under irrigated and drought-stressed conditions. The hierarchical clustering of the wheat genotypes unveiled three drought-tolerant groups. Cluster 1 genotypes showed minimal phenotypic alterations, conferring superior drought tolerance and yield stability than clusters 2 and 3. The polymorphism information content values for the SSR markers ranged from 0.434 to 0.932, averaging 0.83. A total of 458 alleles (18.32 alleles per locus) were detected, with the most polymorphic markers, wmc177 and wms292, having the most alleles (24). A comparative study of SSR diversity among phenotypic clusters indicated that genotypes under cluster 1 had higher genetic diversity (0.879) and unique alleles (47%), suggesting their potential in future breeding programs. The unweighted neighbor-joining tree grouped the wheat genotypes into five major clusters. Wheat genotypes from all phenotypic clusters were distributed throughout all SSR-based clusters, indicating that genetically heterogeneous genotypes were allocated to different drought-tolerant groups. However, SSR-based clusters and model-based populations showed significant co-linearity (86.7%). The findings of the present study suggest that combining reflectance-based indirect phenotyping with SSR-based genotyping might be an effective technique for assessing genetic diversity to improve the drought tolerance of bread-wheat genotypes

Assessment of Genetic Diversity of Bread Wheat Genotypes for Drought Tolerance Using Canopy Reflectance-Based Phenotyping and SSR Marker-Based Genotyping

This study investigated the genetic diversity of bread-wheat genotypes using canopy reflectance-based vegetation indices (VIs) and simple sequence repeat (SSR) marker-based genotyping for drought tolerance. A total of 56 wheat genotypes were assessed using phenotypic traits (combination of VIs and yield traits) and 30 SSR markers. The data of the phenotypic traits were averaged over two growing seasons under irrigated and drought-stressed conditions. The hierarchical clustering of the wheat genotypes unveiled three drought-tolerant groups. Cluster 1 genotypes showed minimal phenotypic alterations, conferring superior drought tolerance and yield stability than clusters 2 and 3. The polymorphism information content values for the SSR markers ranged from 0.434 to 0.932, averaging 0.83. A total of 458 alleles (18.32 alleles per locus) were detected, with the most polymorphic markers, wmc177 and wms292, having the most alleles (24). A comparative study of SSR diversity among phenotypic clusters indicated that genotypes under cluster 1 had higher genetic diversity (0.879) and unique alleles (47%), suggesting their potential in future breeding programs. The unweighted neighbor-joining tree grouped the wheat genotypes into five major clusters. Wheat genotypes from all phenotypic clusters were distributed throughout all SSR-based clusters, indicating that genetically heterogeneous genotypes were allocated to different drought-tolerant groups. However, SSR-based clusters and model-based populations showed significant co-linearity (86.7%). The findings of the present study suggest that combining reflectance-based indirect phenotyping with SSR-based genotyping might be an effective technique for assessing genetic diversity to improve the drought tolerance of bread-wheat genotypes

Cytokinin and gibberellic acid-mediated waterlogging tolerance of mungbean (Vigna radiata L. Wilczek)

Background Mungbean (Vigna radiata L. Wilczek) is one of the most important pulse crops, well-known for its protein-rich seeds. Growth and productivity are severely undermined by waterlogging. Methods In this study, we aim to evaluate how two promising phytohormones, namely cytokinin (CK) and gibberellic acid (GA3), can improve waterlogging tolerance in mungbean by investigating key morphological, physiological, biochemical, and yield-related attributes. Results Our results showed that foliar application of CK and GA3 under 5-day of waterlogged conditions improved mungbean growth and biomass, which was associated with increased levels of photosynthetic rate and pigments. Waterlogged-induced accumulation of reactive oxygen species and the consequently elevated levels of malondialdehyde were considerably reduced by CK and GA3 treatments. Mungbean plants sprayed with either CK or GA3 suffered less oxidative stress due to the enhancement of total phenolics and flavonoids levels. Improvement in the contents of proline and total soluble sugars indicated a better osmotic adjustment following CK and GA3 treatments in waterlogged‐exposed plants. Most fundamentally, CK or GA3-sprayed waterlogged-stressed mungbean plants demonstrated better performance in the aforementioned parameters after the 15-day recovery period as compared to water-sprayed waterlogged-exposed plants. Our results also revealed that CK and GA3 treatments increased yield-associated features in the waterlogged-stressed plant. Here, both phytohormones are efficient in improving mungbean resistance to waterlogging. However, CK was found to be more effective. Overall, our findings suggested that CK or GA3 could be used for managing waterlogging-induced damage to mungbean and perhaps in other cash crops

Pospeševanje odpornosti na sušo pri navadnem fižolu z rizobakterijo Bacillus amyloliquefaciens, ki pospešuje rast rastlin

The study was made to explore the implications of plant growth promoting rhizobacterium in French bean while acclimating to drought stress. Among the bacterial strains used in this study, Bacillus amyloliquefaciens (PPB6) was selected as the suitable candidate for having better growth performances in French bean. Plants provided with drought and PPB6 showed better performances in morpho-physiological attributes as compared to drought-stressed plants only. While facing drought, PPB6 reduced Reactive Oxygen Species (ROS); hydrogen peroxide (H2O2), and lipid peroxidation product; malondialdehyde (MDA), and electrolyte leakage as compared to drought-stressed plants only. Consistently, PPB6 reduced proline, total phenolics and flavonoid contents under drought stress than drought-stressed plants only. Besides, significant reduction of the activity of ascorbate peroxidase, glutathione S-transferase and peroxidase by PPB6 suggesting the lowering of drought-induced oxidative damage by this bacterium. Although, control plants showed best performance in the induction of morpho-physiological parameters and reduction of antioxidative properties, the better permeances in this regard by the plants treated with drought and PPB6 than drought-stressed only, suggesting that PPB6 has the ability to reduce the drought impacts and could partially complements the features of non-stressed control plants. We suggest PPB6 as the potential mitigator of the drought stress in French bean.Raziskava je bila izvedena za preučevanje uporabe rizobakterij, ki pospešujejo prilagajanje navadnega fižola na sušni stres. Z rizobakterijo Bacillus amyloliquefaciens Priest et al., 1987 (PPB6) inokulirane rastline so pokazale boljše morfološke parametre rasti in večji pridelek strokov v primerjavi z neinokuliranimi. PPB6 je povečala učinkovitost fotosinteze v sušnem stresu z izboljšanjem stanja fotosinteznih barvil in večjo fotokemično učinkovitostjo fotosinteze (Fv/Fm) v primerjavi z rastlinami, ki v sušnem stresu niso bile inolkulirane. PPB6 je povečala relativno vsebnost vode (59,67 %) in zmanjšala akumulacijo prolina (0,63 μmol g-1 FM) v razmerah sušnega stresa v primerjavi z neinokuliranimi rastlinami (43,67 % in 1,42 μmol g-1 FM). V sušnem stresu inokulirane rastline so imele manjšo vsebnost vodikovega peroksida, manjšo vsebnost produktov peroksidacije lipidov kot je malondialdehid (0,05 μmol g-1 FM) in manjše puščanje elektrolitov (30,20%) v primerjavi z neinokuliranimi rastlinami rastočimi v razmerah sušnega stresa (136,25 μmol g-1 FM, 0,08 μmol g-1 FM in 55,93 % respectively). V neinokuliranih rastlinah, ki so rastle v razmerah sušnega stresa je bilo ugotovljeno značilno zmanjšanje v vsebnosti celokupnih fenolov in flavonoidov kot tudi v aktivnosti antioksidacijskih encimov kot so askorbat peroksidaza, glutation S-transferaza in peroksidaza. Prepostavljamo, da ima rizobakterija PPB6 sposobnost blaženja učinkov suše pri navadnem fižolu

Plant probiotic bacteria Bacillus and Paraburkholderia improve growth, yield and content of antioxidants in strawberry fruit

Strawberry is an excellent source of natural antioxidants with high capacity of scavenging free radicals. This study evaluated the effects of two plant probiotic bacteria, Bacillus amylolequefaciens BChi1 and Paraburkholderia fungorum BRRh-4 on growth, fruit yield and antioxidant contents in strawberry fruits. Root dipping of seedlings (plug plants) followed by spray applications of both probiotic bacteria in the field on foliage significantly increased fruit yield (up to 48%) over non-treated control. Enhanced fruit yield likely to be linked with higher root and shoot growth, individual and total fruit weight/plant and production of phytohormone by the probiotic bacteria applied on plants. Interestingly, the fruits from plants inoculated with the isolates BChi1 and BRRh-4 had significantly higher contents of phenolics, carotenoids, flavonoids and anthocyanins over non-treated control. Total antioxidant activities were also significantly higher (p \u3c 0.05) in fruits of strawberry plants treated with both probiotic bacteria. To the best of our knowledge, this is the first report of significant improvement of both yield and quality of strawberry fruits by the application of plant probiotic bacteria BChi1 and BRRh-4 in a field condition. Further study is needed to elucidate underlying mechanism of growth and quality improvement of strawberry fruits by probiotic bacteria

Physiological and Biochemical Dissection Reveals a Trade-Off between Antioxidant Capacity and Heat Tolerance in Bread Wheat (<i>Triticum aestivum</i> L.)

Heat stress alters photosynthetic components and the antioxidant scavenging system, negatively affecting plant growth and development. Plants overcome heat stress damage through an integrated network involving enzymatic and non-enzymatic antioxidants. This study aimed to assess physiological and biochemical responses in contrasting thermo-tolerant wheat varieties exposed to 25 °C (control) and 35 °C (heat stress), during the seedling stage. Our results revealed a substantial decrease in the photosynthetic pigments, carotenoids, anthocyanin content, and increased membrane injury index, malondialdehyde, methylglyoxal (MG), H2O2 contents and lipoxygenase activity compared to non-stress wheat seedlings. The heat-tolerant variety BARI Gom 26 (“BG26”) maintained higher cellular homeostasis compared to the heat susceptible variety Pavon 76 (“Pavon”), perpetuated by higher accumulation of proline, glycine betaine, ascorbate-glutathione cycle associated enzymes, reduced glutathione and ascorbate concentration in plant cells. Significantly lower levels of MG detoxification and antioxidant activities and ascorbate-glutathione cycle-related enzymatic activities lead to increased susceptibility in variety “Pavon”. Hierarchical clustering and principal component analysis revealed that variety “BG26” possess a combination of biochemical responses tailoring antioxidant activities that induced a higher level of tolerance. Taken together, our results provide a pipeline for establishing a trade-off between antioxidant capacity and heat tolerance to facilitate functional genomics and translational research to unravel underlying mechanisms to better adapt wheat to heat stress