Fifteen genotypes of sweet potato were evaluated for salinity stress tolerance under in vitro NaCl mediated salinity stress conditions (MS, MS + 0.5% and MS + 1.0% NaCl). The growth parameters such as number of leaves, number of shoots, number of roots, length of plantlets and length of roots decreased significantly among the genotypes with increase in level of salinity. Of the 15 genotypes tested, six genotypes (108X1, 90/606, 90/696, CIP 8, S-30X15 and SP-61) were unable to sprout even at 0.5% NaCl and were characterized as susceptible to salt stress, three genotypes (CIP 6, 90/774 and CIP 3) which could tolerate 0.5% NaCl as moderately tolerant and six genotypes (CIP 12, CIP 13, JO 14, JP 13, and Gouri) as tolerant to salinity at 1.0% NaCl. Amongst the six genotypes showing tolerance to 1.0% NaCl, the exotic genotypes--JP 13, CIP 12 and indigenous one SB-198/115 continued to exhibit significant higher values for growth parameters over the susceptible one. Based on the performance under NaCl mediated salinity stress (1.0%), the pattern of salinity tolerance in the genotypes through shoot apex culture was JP 13 . The effect of salt stress on the activity of antioxidative enzymes was studied in leaves of 8-week-old plantlets of those six genotypes, which responded at higher NaCl stress along with a susceptible genotype 90/606. In leaves of salt stressed plants, superoxide dismutase (SOD), guaiacol peroxidase (GPX) and catalase (CAT) activities increased when compared with the stress free control. The increase was more pronounced in the tolerant genotypes than that in the susceptible one. These results indicate that oxidative stress may play an important role in salt stressed sweet potato plants and that the greater protection of tolerant plants from salt induced oxidative damage results, at least in part, through the increase in the activity of antioxidant enzymes.

A secreted cellulase of Xanthomonas oryzae pv. oryzae induces innate immune responses in rice including a hypersensitive response (HR) like reaction. Microarray analysis was conducted using RNA isolated 12 h following ClsA treatment of leaves. BLAST searches were performed for the 267 (152 up-and 115 downregulated) differentially expressed (≥2-fold) genes. A number of defense and stressresponse functions are upregulated while a number of functions involved in metabolism and transport are downregulated following induction of HR. A significant proportion of the differentially expressed genes (41/267) are predicted to encode transcription factors. Co-infiltration of X. oryzae pv. oryzae suppresses ClsA-induced expression of two transcription factors, OsAP2/ethylene response factor (ERF) and OsRERJ1, that are predicted to be involved in the jasmonic-acid-mediated defense pathway. Transient transfer of OsAP2/ERF via Agrobacterium results in the induction of callose deposition, programmed cell death, and resistance against subsequent X. oryzae pv. oryzae infection.

The objective of the study was to identify the fertility‐associated metabolites in bovine spermatozoa using liquid chromatography‐mass spectrometry (LC‐MS). Six Holstein Friesian crossbred bulls (three high‐fertile and three low‐fertile bulls) were the experimental animals. Sperm proteins were isolated and protein‐normalized samples were processed for metabolite extraction and subjected to LC‐MS/MS analysis. Mass spectrometry data were processed using iMETQ software and metabolites were identified using Human Metabolome DataBase while, Metaboanalyst 4.0 tool was used for statistical and pathway analysis. A total of 3,704 metabolites belonging to various chemical classes were identified in bull spermatozoa. After sorting out exogenous metabolites, 56 metabolites were observed common to both the groups while 44 and 35 metabolites were found unique to high‐ and low‐fertile spermatozoa, respectively. Among the common metabolites, concentrations of 19 metabolites were higher in high‐fertile compared to low‐fertile spermatozoa (fold change > 1.00). Spermatozoa metabolites with variable importance in projections score of more than 1.5 included hypotaurine, d‐cysteine, selenocystine. In addition, metabolites such as spermine and l‐cysteine were identified exclusively in high‐fertile spermatozoa. Collectively, the present study established the metabolic profile of bovine spermatozoa and identified the metabolomic differences between spermatozoa from high‐ and low‐fertile bulls. Among the sperm metabolites, hypotaurine, selenocysteine, l‐malic acid, d‐cysteine, and chondroitin 4‐sulfate hold the potential to be recognized as fertility‐associated metabolites.

Assessment of the differential expression of antioxidative enzymes and their isozymes, was done in 30 day-old ex vitro raised plants of three highly resistant (DP-25, Jhankri and Duradim) and one highly susceptible (N-118) genotypes of taro [Colocasia esculenta (L.) Schott]. Antioxidative enzymes were assayed in the ex vitro plants, 7 days after inoculation with the spores (15,000 spores ml(-1) water) of Phytophthora colocasiae Raciborski to induce taro leaf blight disease. Uninoculated ex vitro plants in each genotype were used as control. The activity of superoxide dismutase (SOD) and guaiacol peroxidase (GPX) increased under induced blight condition when compared with control. Increase in antioxidative enzymes was more (67-92%) in the resistant genotypes than that (21-29%) of the susceptible genotype. The zymograms of SOD and GPX in the resistant genotypes, with pathogenic infection, showed increased activity for anodal isoform of SOD and increased expression and/or induction of either POX 1 or POX 2 isoforms of GPX. In susceptible genotype, expression of the above isoforms was faint for SOD and nearly absent for GPX under both blight free and induced blight conditions. Induction and/or increased activity of particular isoform of SOD and GPX against infection of Phytophthora colocasiae in the resistant genotypes studied led to the apparent conclusion of linkage of isozyme expression with blight resistance in taro. This might be an important criterion in breeding of taro for Phytophthora leaf blight resistance.

Climate change is a critical yield–limiting factor that has threatened the entire global crop production system in the present scenario. The use of biostimulants in agriculture has shown tremendous potential in combating climate change–induced stresses such as drought, salinity, temperature stress, etc. Biostimulants are organic compounds, microbes, or amalgamation of both that could regulate plant growth behavior through molecular alteration and physiological, biochemical, and anatomical modulations. Their nature is diverse due to the varying composition of bioactive compounds, and they function through various modes of action. To generate a successful biostimulatory action on crops under different parameters, a multi–omics approach would be beneficial to identify or predict its outcome comprehensively. The ‘omics’ approach has greatly helped us to understand the mode of action of biostimulants on plants at cellular levels. Biostimulants acting as a messenger in signal transduction resembling phytohormones and other chemical compounds and their cross–talk in various abiotic stresses help us design future crop management under changing climate, thus, sustaining food security with finite natural resources. This review article elucidates the strategic potential and prospects of biostimulants in mitigating the adverse impacts of harsh environmental conditions on plants.

Influence of polyethylene glycol (PEG) mediated osmotic stress on reactive oxygen species (ROS) scavenging machinery of Chinese potato (Solenostemon rotundifolius (Poir.) J. K. Morton) was investigated. Five genotypes of Chinese potato were raised in Murashige and Skoog (MS) basal medium containing 6-benzylaminopurine (BAP, 1 mg L-1) along with various concentrations of PEG-6000 mediated stress conditions (0,-0.2 and-0.5 MPa) and evaluated for osmotic stress tolerance in vitro. The medium containing PEG-6000 had a detrimental effect on plantlet growth and development while compared with the control. Accumulation of H 2 o 2 was lower in Sreedhara and Subala and higher in Nidhi under PEG stress, which was evident by in situ detection in leaves. Lipid peroxidation product such as malondialdehyde (MDA) content was increased due to PEG stress which was more in susceptible genotype than that in tolerant ones. An enhanced ROS-scavenging antioxidant enzyme was observed under stress with respect to the control. The enzymes of ascorbate-glutathione cycle showed an important role in scavenging ROS. The imposition of PEG stress also increased the non-enzymatic antioxidants viz., the ascorbate and reduced glutathione content which was prominent in tolerant genotypes in comparison to susceptible. The present study indicated that, Sreedhara and Subala showed more tolerance to osmotic stress with better ROS scavenging machineries which would be the lines of interest for augmenting future breeding strategies in this climate resilient minor tuber crop. Chinese potato (Solenostemon rotundifolius (Poir.) J. K. Morton), belongs to the family Lamiaceae, is one of the important minor tuber crops grown in the tropics of the world. The tubers of this crop are rich in carbohydrates and minerals 1 which provide essential dietary and energy supplements during the lean periods. It could be the better alternative to potato (Solanum tuberosum L.) for the tropics of the world under changing climatic conditions; where potato fails to grow due to global warming. Chinese potato can grow in a wide range of environmental conditions. Despite its wide adaptability, the productivity (18-20 t/ha) was severely affected due to osmotic stress. Under natural conditions, plant growth and development often challenged by various stresses 2 , of which, osmotic stress is one of the most limiting factors which can cause 20-98% of yield reductions 3. To elucidate the plant response to osmotic stress, in vitro cultures are preferred as it minimizes nutrient and environmental variations under control conditions 4. In this investigation, we have used polyethylene glycol (PEG-6000) to induce osmotic stress conditions in vitro. In plant osmotic stress studies, PEG is widely used as a potential osmoticum in the nutrient medium to induce water deficit 5. Induced osmotic stress resulted in overproduction of reactive oxygen species (ROS) which was considered as a hallmark of plant stress response. To scavenge the toxic consequences of ROS, plant deploys antioxidative mecha...

Taro hybrid TSL (Topi X Satasankha), along with its parental lines, was evaluated for stress tolerance under in vitro and in vivo polyethelene glycol (PEG) -mediated osmotic stress conditions. Aseptic cultures were raised in vitro under control and PEG-mediated stress conditions. Stress index for survival and growth parameters like rooting ability in cultures and number of leaves produced per plantlet revealed the better response of hybrid lineTSL than its parental lines. The plantlets were hardened and transferred to pots for evaluation of morpho-physico-biochemical parameters under PEG-mediated osmotic stress conditions. Significant variations were observed in stress index for plant height. number of leaves, leaf area, % relative water content (RWC), chlorophyll stability mdex (CSI), % injury by dessication and yield. Decline in biochemical traits like protein content but increase in catalase and peroxidase activities was observed under the osmotic stress conditions. Less variation in morpho-physico-biochemical characters were recorded in TSL under stress conditions as compared to its parents. The hybrid line-TSL showed tolerance to osmotic stress with a minimum yield reduction. TSL can be used for the future breeding program for the development of drought tolerant lines and can become the source of favorable genes for drought tolerance in taro.

Aim: To determine the serum variations of two major acute phase proteins, serum amyloid A (SAA) and haptoglobin (Hp) levels in crossbred endometritis cows following pre and post immunomodulation therapy.Materials and Methods: 21 endometritis cows were randomly assigned to three groups (n=7) and treated with three different immunomodulators while seven healthy cows served as control. Uterine flushing collected from all animals was subjected to bacteriological study and serum samples were analyzed for SAA and Hp by sandwich ELISA method.Results: Escherichia coli was most prevalent Gram-negative bacteria (6.02 × 10 6 CFU/ml) while Staphylococcus (0.86 × 10 6 CFU/ml) and Streptococcus (0.52 × 10 6 CFU/ml) were most predominant Gram-positive species isolated from uterine flushing. The pre-treatment SAA values (μg/ml) varied significantly (p<0.01) between the treatment groups whereas no difference was observed in post-treatment groups. No significant difference (p<0.01) was observed for Hp values between the treatment groups, but the mean SAA (μg/ml) and Hp (μg/ml) levels were significantly (p<0.01) higher in pre-treatment when compared to post-treatment within the groups. Conclusion:In the diagnosis and monitoring of bovine endometritis, both SAA and Hp might serve as reliable biomarkers.