Screening and Biochemical Characterization of Wheat Cultivars Resistance to Magnaporthe oryzae pv Triticum (MoT)

Global food security is seriously threatened due to increased frequency and occurrence of fungal diseases. One example is wheat blast caused by Magnaporthe oryzae is a fungal diseases of rice, wheat, and other grasses, that can destroy the whole food production to sustain millions of people. Wheat blast was first detected in february 2016 with a serious outbreak in Asia. Assessment of the available germplasms to stress tolerant/resistant is one of the best options for developing stress tolerant crop varieties. In this study, a total of sixteen wheat cultivars were collected and test their disease severity to blast pathogen Magnaporthe oryzae pv. Triticum (MoT). Among the varieties, BARI Gom 33 exhibited partially resistance against blast pathogen, whereas all other genotypes become susceptible to MoT. Different yield and yield contributing characters of both resistant and susceptible cultivars were also evaluated and found no significant differences among them. To understand the underlying mechanism of resistance in BARI Gom 33, antioxidant enzyme activity, concentration of reactive oxygen species and cellular damage after fungal infection were also evaluated and found that activities of ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) were higher in BARI Gom 33 than BARI Gom 25 and BARI Gom 31. The hydrogen peroxide (H2O2) and malondealdehyde (MDA) content in BARI Gom 33 was low compare to BARI Gom 25 and BARI Gom 31, which may due to greater increase of the APX, CAT and POD in resistant genotypes. Thus, it may suggest that a more efficient antioxidative defense system in BARI Gom 33 during the infection process of M. oryzae restricts the cell damage caused by the fungus. The identified genotypes can either be used directly in the blast prone area or as a source of resistance to further development of blast resistance high yielding wheat variety

Developing Student Engagement in China Through Collaborative Action Research

As its market and society open up, China has transformed itself from a closed agrarian socialist economy to an urban state and an economic force. This has released accumulated tourism demand, led to the development of a diversified industry, and the spread of university and vocational courses in this field. However, the industry faces challenges to recruit and retain staff, with tourism education in higher education blamed for the shortfall in numbers and quality of candidates with suitable purpose, knowledge, and passion to serve. This chapter provides a background to the development of and problems facing tourism education in China, and suggests how to support student engagement and hence the future workforce

Characterization of wheat genotypes for terminal heat stress tolerance in Bangladesh

This study was aimed to determine the types and levels of variability, heritability, genetic progress, relationships between yield and the features that contribute to it, and some key indicators of terminal heat stress tolerance. Twenty different wheat genotypes were planted in the fields over the course of six different treatments spaced 10 days interval following a Randomized Complete Block Design (RCBD) with three replications. A high degree of significant variation was observed for all the characters studied. Estimates of the genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) revealed that the phenotypic coefficient of variation was higher than the genotypic coefficient of variation, which indicates a large effect of environment on the expression of the characters studied. The highest estimates of PCV and GCV were observed for grain yield/plant followed by the number of tillers/plant. Heritability estimates revealed that characters like pollen fertility and sterility exhibited the highest heritability followed by days to maturity. The genetic advance was higher for grains/plants followed by plant height. Grain yield showed significant and positive phenotypic and genotypic correlations with grains/plant and 100-grain weight. Phenotypic path analysis revealed a significant direct positive effect of 100-grain weight on grain yield. Principal component analysis (PCA) revealed that the first five components having greater than one Eigenvalue contributed to 83.41% variability. The heat stress tolerance indices revealed that Bijoy and BARI Gom-25 had the lowest tolerance index (TOL), stress susceptibility index (SSI) values and highest yield susceptibility index (YSI) values which show more tolerance and less susceptibility to terminal heat stress and produce moderate grain yield under terminal heat stress. Balaka and Shughat had the highest mean productivity (MP), geometric mean productivity (GMP), and stress tolerance index (STI) values and produce high yields under terminal heat stress conditions. [J Bangladesh Agril Univ 2023; 21(1.000): 23-32

Genotype-environment interaction for grain and sink characters in spring wheat (Triticum aestivum L.)

The paper presented herein dealt with studies on genotype-environment interaction following genetic approach for grain yield and different sink characters in seven crosses (Balaka x Pavon, Gourav x Kanchan, Kanchan x Sonora, Gourav x Protiva, Kanchan x Pavon, Kanchan x Pavon, Sonora x Pavon) of spring wheat grown at BAU in the winter season of 2005. According to G x E interaction study on crosses genotype, environment and GxE interaction were significant for all the characters. Relative contribution of different parameters such as additive [d], dominance [h], environment ej, additive x env. gdj and dominance x env. ghj were determined for all the five characters studied. Most of the crosses for yield/plant showed incomplete dominance, while one cross (Gaurab x Protiva) showed overdominance of increasing allele and another one (Balaka x Pavon) showed overdominance of decreasing allele. The expression of heterosis for yield per plant in Gaurab x Kanchan was done away within adverse environment. Profound environmental effect was observed for days to 50% flowering, number of spikelets per spike, number of grains per spike, yield per plant and 100- grain weight. In general, hybrids were more reactive to the changes of environment than their parents for all the characters studied

A Polyamine Oxidase from <i>Selaginella lepidophylla</i> (SelPAO5) can Replace AtPAO5 in <i>Arabidopsis</i> through Converting Thermospermine to Norspermidine instead to Spermidine

Of the five polyamine oxidases in Arabidopsis thaliana, AtPAO5 has a substrate preference for the tetraamine thermospermine (T-Spm) which is converted to triamine spermidine (Spd) in a back-conversion reaction in vitro. A homologue of AtPAO5 from the lycophyte Selaginella lepidophylla (SelPAO5) back-converts T-Spm to the uncommon polyamine norspermidine (NorSpd) instead of Spd. An Atpao5 loss-of-function mutant shows a strong reduced growth phenotype when growing on a T-Spm containing medium. When SelPAO5 was expressed in the Atpao5 mutant, T-Spm level decreased to almost normal values of wild type plants, and NorSpd was produced. Furthermore the reduced growth phenotype was cured by the expression of SelPAO5. Thus, a NorSpd synthesis pathway by PAO reaction and T-Spm as substrate was demonstrated in planta and the assumption that a balanced T-Spm homeostasis is needed for normal growth was strengthened

Garlic bulb extracts inhibitory to Phomopsis vexans

Garlic bulbs (A/hum sativum) extracts were made in benzene, diethyl ether, dichloromethane and water. at room temperature (25±2 °C). The solvents were These extracts were applied to determine their inhibitory effects against Phomopsis vexans. TLC of these extracts was done by using different pure and suitably mixed solvents.Growth inhibition test of Phomopsis vexans by each of these extracts in different solvents revealed different mode of action. Dichloromethane extract of garlic were found to be very satisfactory in inhibition (83.52-86.45 %).TLC of these extracts showed the presence of a number of compounds having very low to high polarity. Four single compounds were separated and tested against Phomopsis vexans individually. Among the separated compounds, three compounds P1B1, BlEi and E were completely inhibitory against Phomopsis vexans while the other compound P1133 had little inhibitory effect. The Rf values of TLC spots produced by different compounds present in garlic extract revealed their distinct polar and non polar nature. These studies lead us in near future to the elucidation of complete structure of these active compounds

Identification of the actual coding region for polyamine oxidase 6 from rice (OsPAO6) and its partial characterization

<p>Polyamines (PA) in plant play roles in growth and development and in responses to environmental stresses. The family of polyamine oxidases (PAO) contributes to a balanced homeostasis of PAs catalyzing two different reactions, terminal catabolic (TC) and back-conversion (BC) pathway, in PA catabolism. From the seven PAOs encoded by the rice genome (OsPAO1 – OsPAO7) OsPAO6 could so far not be characterized due to failure in obtaining the coding cDNA based on accessions in the genomic databases. We report cloning and characterization of the correct OsPAO6 cDNA with a length of 1,742 bp. The 1,491 bp long open reading frame codes for a 497-amino acid protein from nine exons. The protein which has 92% identity to OsPAO7 localizes to plasma membrane.</p