Identification of microRNAs Responding to Aluminium, Cadmium and Salt Stresses in Barley Roots

Plants are frequently exposed to various abiotic stresses, including aluminum, cadmium and salinity stress. Barley (Hordeum vulgare) displays wide genetic diversity in its tolerance to various abiotic stresses. In this study, small RNA and degradome libraries from the roots of a barley cultivar, Golden Promise, treated with aluminum, cadmium and salt or controls were constructed to understand the molecular mechanisms of microRNAs in regulating tolerance to these stresses. A total of 525 microRNAs including 198 known and 327 novel members were identified through high-throughput sequencing. Among these, 31 microRNAs in 17 families were responsive to these stresses, and Gene Ontology (GO) analysis revealed that their targeting genes were mostly highlighted as transcription factors. Furthermore, five (miR166a, miR166a-3p, miR167b-5p, miR172b-3p and miR390), four (MIR159a, miR160a, miR172b-5p and miR393) and three (miR156a, miR156d and miR171a-3p) microRNAs were specifically responsive to aluminum, cadmium and salt stress, respectively. Six miRNAs, i.e., miR156b, miR166a-5p, miR169a, miR171a-5p, miR394 and miR396e, were involved in the responses to the three stresses, with different expression patterns. A model of microRNAs responding to aluminum, cadmium and salt stresses was proposed, which may be helpful in comprehensively understanding the mechanisms of microRNAs in regulating stress tolerance in barley.

In-Vitro Study on Fermentation Characteristics of Different Hulless Barley Cultivar Flakes

Barley (Hordium vulgare L.) grain is an important food ingredient due to the presence of essential compounds like β-glucans, proteins, resistant starch, phenolic compounds etc. β-glucans are able to lower cholesterol level in blood plasma and the glycaemic index, to enhance lipid metabolism and to reduce the risk of colon cancer. Hulless barley cultivars are more suitable to the human diet, because the hulls can be easily removed, as well as minimal grain processing in food production contributes to the full benefit of the whole grain. Several studies show that hulless grains have a higher digestible energy, and they have higher protein content compared to hulled grains. Different cultivars have unique composition and physical properties. The hulless barley cultivars are less studied than hulled barley and oats. The aim of this study was to evaluate the fermentation characteristics of flakes of different hulless barley cultivars in vitro and to analyse the fermentation pattern of β-glucans and proteins. Samples of six hulless barley cultivar flakes with different β-glucan (4.17–6.59%), soluble dietary fibre (18.1–32.0%) and resistant starch (0.74–10.65%) content were boiled in water 10 min, and the obtained porridge samples were treated under in vitro fementation conditions. The concentration of fermented porridge solids as well as β-glucans and proteins was measured. The concentration of undigested solids varied from 38.3 to 61.0% depending on barley cultivar. The concentration of protein was not significantly changed, but β-glucan concentration was significantly decreased after in vitro digestion comparing to indigestible samples.

Microalgae and Biochar Agro-Fertilization of the Palestinian Rehan Barley Cultivar under Salinity Stress

The efficient transfer of nutrients to plants in the form of biofertilizers on poor substrate was investigated. Biochar and dried algae biomass as well as mineral fertilizer were used to test the growth of the Palestinian ‘Rehan’ barley cultivar under salinity stress (4, 8, and 16 mS/cm EC). Rehan cultivar showed resilience to moderate levels of salinity and could still grow under high salinity stress (16 mS/cm EC). Rehan barley possessed better growth at early growth stage under the applied biofertilizers such as dried freshwater algal biomass (Chlorella vulgaris) and nutrient-laden biochar. It showed better growth than wheat (ssp. scirocco) under the same conditions. Its growth was highly improved by biochar treatment in low and moderate salinity conditions. Moreover, the combined effect between biochar and dried algae biomass could improve Rehan barley growth, but less than the effect of each biofertilizer separately. The biofertilizers affected most plant growth parameters under the salinity level of 4 and 8 mS/cm EC positively, while the growth declined again at 16 mS/cm EC. Overall, the biochar treatment showed the same effect as the mineral fertilizer on most of the parameters. The dried algae biomass and biochar also affected soil conditions. The highest soil water content (15.09%) was found in algae biomass treatments with 16 mS/cm EC. Biochar with 8 and 16 mS/cm EC had the highest pH value (8.63) near the rhizospheres. The nitrogen level was highest in the bottom soil sample (0.28 g N/kg soil) for biochar with 0 and 4 mS/cm EC. Meanwhile, the phosphate concentration was the highest (3.3 mg PO3−2/kg soil) in algae fertilizer treatments with 0 mS/cm EC in the bottom soil sample and lowest (4.14 mg PO3−2/kg soil) for the biochar with 8 mS/cm EC. The dried algae biomass and the biochar treatments can subsequently be viewed as conditioner substrates for improving the quality and fertility of the soil. Where possible, they should be considered as complement or replacement of mineral and manure fertilization to improve the impact on soil and environment.

Evaluation of barley testing locations in Ontario

In order to develop new barley cultivars, promising genotypes are evaluated for their performance each year at a number of test locations representing the target region. In this study, we analyzed the Ontario barley registration trial data from 2015 to 2020 to understand the barley mega-environment in Ontario and to evaluate the suitability of the test locations. The analysis showed that the barley test locations fall into two mega-environments, with a major mega-environment consists of five test locations and a minor mega-environment with a single test location. Among the six test locations used for the barley registration trials, Palmerston was found to be the most desirable for the barley cultivar evaluation representing the Ontario barley growing region. This study also identified OB2930-35, a recently released cultivar, to be both high yielding and stable across Ontario. These findings are useful for future barley breeding and cultivar evaluation in Ontario.

Genome Assembly of the Canadian Two-row Malting Barley Cultivar AAC Synergy

Barley (Hordeum vulgare L.) is one of the most important global crops. The six-row barley cultivar Morex reference genome has been used by the barley research community worldwide. However, this reference genome can have limitations when used for genomic and genetic diversity analysis studies, gene discovery, and marker development when working in two-row germplasm that is more common to Canadian barley. Here we assembled, for the first time, the genome sequence of a Canadian two-row malting barley, cultivar AAC Synergy. We applied deep Illumina paired-end reads, long mate-pair reads, PacBio sequences, 10X chromium linked read libraries, and chromosome conformation capture sequencing (Hi-C) to generate a contiguous assembly. The genome assembled from super-scaffolds had a size of 4.85 Gb, N50 of 2.32 Mb and an estimated 93.9% of complete genes from a plant database (BUSCO, benchmarking universal single-copy orthologous genes). After removal of small scaffolds (< 300 Kb), the assembly was arranged into pseudomolecules of 4.14 Gb in size with seven chromosomes plus unanchored scaffolds. The completeness and annotation of the assembly were assessed by comparing it with the updated version of six-row Morex and recently released two-row Golden Promise genome assemblies.

Evaluation of resistance of some barley varieties to wheat stem sawfly (Hymenoptera: Cephidae) in Hama Governorate

Wheat stem sawfly (Hymenoptera: Cephidae) is a significant pest on wheat and barley in Syria, and host plant resistance is one of the most effective mitigation of wasps damage. The preference for laying eggs among females of wheat stem sawfly (WSS) was studied in some cultivation barley varieties in Syria, and the reasons for this preference, by comparing the characteristics of plant height in the stages of early wasp propagation, phenological development stages synchronized with late propagation wasps stages that are known having attraction influence for female wasps to put eggs, within the natural conditions at the place of experimenting in Soran region, northern of Hama, about 20 km. The results showed a great variation in the infection rates between the tested barley cultivar varieties. Female of wheat stem sawfly (WSS) preferred to lay eggs in the barley cultivar (Arabi Aswad) (Aswad means black), which was a sensitive variety for infection althoughit is not being the highest height plant in the early stages or the less developed in the late stages of wheat stem sawfly spread, whereas the rest of the tested varieties distinguished (Furat 1, Furat 3, Furat 4, Furat 5, Furat 6, Furat 9, Arabi Abiad, and Arabi Abiad Mohsan) (Abiad means white, Mohsan means improved) by its relative resistance to the injury. Our results suggest conducting other studies to reach the reasons forpredilection preference or lack of preference and benefit from them later for reducing losses resulting from this injury.

Galinsoga parviflora Response to Different Application Rates of the Herbicide Chwastox Turbo 340 SL in Spring Barley

The aim of this study was to evaluate the response of <em>Galinsoga parviflora </em>to different doses of the herbicide Chwastox Turbo 340 SL [2-methyl-4- chlorophenoxyacetic acid (MCPA) + dicamba] used alone and with an adjuvant. The study was conducted on the spring barley cultivar ‘Suweren.’ During the tillering stage of spring barley, a weed control treatment was applied using Chwastox Turbo 340 SL at a rate of 100% and at rates reduced by 33% and 50%, and was applied either alone or with an oil adjuvant. Plots without herbicide and adjuvant application were the control treatment. The present study showed that in spring barley the largest plants of <em>G. parviflora</em>, which produced the highest number of branches, flower heads, and achenes, occurred in the control treatment where no herbicide and adjuvant were applied. Morphology, productivity, and biomass were not found to vary greatly between <em>G. parviflora </em>plants occurring in the plots where the reduced rates of Chwastox Turbo 340 SL and in those where the manufacturer’s recommended rate were applied. The number of achenes produced by <em>G. parviflora </em>was positively correlated with plant height and negatively with plant biomass. The germination capacity of <em>G. parviflora </em>diaspores was not significantly different between the herbicide protection treatments.