Culture Of Barley Research Articles

The effect of plant growth promoting bacteria both in vitro and hydroponic culture of barley (Hordeum vulgare) growth

The effect of plant growth promoting bacteria both in vitro and hydroponic culture of barley (Hordeum vulgare) growth

Generating homozygous mutant populations of barley microspores by ethyl methanesulfonate treatment

AbstractInduced mutations are important for genetic research and breeding. Mutations induced by physical or chemical mutagenesis are usually heterozygous during the early generations. However, mutations must be fixed prior to phenotyping or field trials, which requires additional rounds of self-pollination. Microspore culture is an effective method to produce double-haploid (DH) plants that are fixed homozygotes. In this study, we conducted ethyl methanesulfonate (EMS)-induced mutagenesis of microspore cultures of barley (Hordeum vulgare) cultivar ‘Hua30’ and landrace ‘HTX’. The EMS concentrations were negatively correlated with the efficiency of callus induction and the frequency of mutant plant regeneration. The two genotypes showed different regeneration efficiencies. The phenotypic variation of the regenerated M1 plants and the presence of genome-wide nucleotide mutations, revealed by whole-genome sequencing, highlight the utility of EMS-induced mutagenesis of isolated microspore cultures for developing DH mutants. Genome-wide analysis of the mutation frequency in the regenerated plants revealed that a considerable proportion of mutations resulted from microspore culture (somaclonal variation) rather than EMS-induced mutagenesis. In addition to producing a population of 1972 homozygous mutant lines that are available for future field trials, this study lays the foundation for optimizing the regeneration efficiency of DH plants and the richness of mutations (mainly by fine-tuning the mutagen dosage).

Supplementation of the Plant Conditioner ELICE Vakcina® Product with β-Aminobutyric Acid and Salicylic Acid May Lead to Trans-Priming Signaling in Barley (Hordeum vulgare).

Plant immunological memory, priming, is a defense mechanism that can be triggered by external stimuli, leading to the activation of biochemical pathways and preparing plants for disease resistance. Plant conditioners improve yield and crop quality through nutrient efficiency and abiotic stress tolerance, which is enhanced by the addition of resistance- and priming-induced compounds. Based on this hypothesis, this study aimed to investigate plant responses to priming actives of different natures, including salicylic acid and beta-aminobutyric acid, in combination with the plant conditioning agent ELICE Vakcina®. Phytotron experiments and RNA-Seq analyses of differentially expressed genes using the combinations of these three investigated compounds were performed in a barley culture to investigate possible synergistic relationships in the genetic regulatory network. The results indicated a strong regulation of defense responses, which was enhanced by supplemental treatments; however, both synergistic and antagonistic effects were enhanced with one or two components, depending on the supplementation. The overexpressed transcripts were functionally annotated to assess their involvement in jasmonic acid and salicylic acid signaling; however, their determinant genes were highly dependent on the supplemental treatments. Although the effects overlapped, the potential effects of trans-priming the two supplements tested could be largely separated.

Gum Arabic influences the activity of antioxidant enzymes during androgenesis in barley anthers

This study investigated the antioxidant activity of gum Arabic (GA) during androgenesis in barley anthers. After stress pretreatment the anthers were cultured in the presence of 10 mg L−1 GA (Gm) or on control medium (Cm) and compared with respect to activity of selected antioxidant and respiratory enzymes and endogenous hydrogen peroxide (H2O2) content. The anthers from Cm and Gm differed in the strategy against H2O2 overproduction, in that the total peroxidase (POX) activity and the number of POX isoforms were significantly higher in Gm- than in Cm-cultured material. High POX activity on Gm paralleled with H2O2 decrease, suggesting the utilization of this chemical for the POX-mediated cell wall formation and reconstruction during growth of multicellular structures. The total superoxide dismutase (SOD) activity on Cm and Gm were at similar level for most of the culture period but the activity of MnSOD was dozen times higher on Gm and this coincided with high activity of fumarase and cytochrome c oxidase. It indicates close interplay between efficient antioxidative protection and high metabolic rate accompanying efficient androgenesis. Mass spectrometry analysis confirmed the presence of POX and other antioxidative and defense enzymes in protein fraction of GA used in the experiments, however as revealed by 2,2-diphenyl-1-picrylhydrazyl assay, the Gm and Cm displayed similar total antioxidant capacity. Thus, the effect of GA on androgenic cultures of barley can be linked to its influence on the activity of anther antioxidant system, rather than its native antioxidative properties.

Application of Straw and Biopreparations as a Sustainable Method for Increasing the Organic Carbon Content and Chemical, Physical, and Biological Soil Properties in Spring Barley Culture

Increasing climate change, through its impact on the economy, results in measures to reduce its negative effects. In agriculture, the expected positive effects may come from the implementation of practices with high carbon sequestration potential (e.g., straw incorporation). The idea of using straw as an energy feedstock requires an in-depth analysis of the impact of this practice on the organic carbon content of arable soils. Straw incorporation combined with the use of biopreparations can provide an attractive alternative to conventional fertilization and plant protection systems. This study aimed to assess the effect of straw, effective microorganisms preparation, and biostimulant on the physicochemical and biological soil parameters. The analyses included organic carbon, available P, K, and Mg, total and mineral nitrogen content, pH, bulk density, soil penetration resistance, and the number of soil-culturable heterotrophic bacteria, actinobacteria, and fungi determination. It was found that straw and EM addition resulted in the highest SOC content. Statistically lower values of bulk density and soil penetration resistance were also observed after straw incorporation. The results of our research revealed that, while the addition of straw beneficially affects soil quality, the impact of biopreparations application on soil parameters varies depending on the experimental combination used.

. Influence of critical excess of microelements on development of barley culture (Hordeum)

Aspects of ecological danger of microelements imbalance in the soil-plant system are stated. The supercritical supply of nutrients to crops can be accompanied by various emergencies and man-made disasters, including military, chemical and pyrogenic. The main signs of toxic effects of micronutrients excess on cereals are presented. There is a positive linear correlation between soil contamination and reduced grain yields. The purpose, tasks and basic conditions of vegetative laboratory experiment on cultivation of barley of Virazh variety on the substrate of soil mix «Green Line» are presented. The peculiarity of the research is to study the influence of monoelement supercritical concentrations of Zn, Cu, Mo in the conditions of root and foliar feeding in barley cultivation. 7 experimental vegetation schemes of soil-plant with the use of sub-root and foliar receipt were studied. Based on the results of a 57-day experiment, quantitative parameters of culture, leaf morphology and root system were determined. Peculiarities of plant development at supercritical levels of microelements receipt and their deviation from the conditions of control plants within significant biogeochemical excess of Zn, Cu, Mo in soils are described. The inflow of zinc on the soil surface inhibits the relative development of the root system by 1.2 times and increases the height of shoots and leaves. The inflow of zinc on the plant surface inhibits the development of the leaf apparatus of barley 1.4 times and promotes the development of the root system. The influx of copper on the soil surface slightly inhibits the relative development of the root system and the height of the shoots. The influx of copper on the surface of the plant slightly inhibits the development of the leaf apparatus and does not change the root system of barley. The inflow of molybdenum to the soil surface inhibits the relative development of the root system by 1.4 times, and the growth of stem and leaf apparatus by 1.1–1.2 times. The entry of molybdenum on the surface of barley crops is less harmful than in the soil. It has been established that the greatest danger for the root system of barley and the location of its sprouts is the supercritical supply of molybdenum, which increased the position of the sprouts by 4–5 times and reduced the development and length of the root system to 2 times. The greatest danger for the leaf plate of barley sprouts is the supercritical foliar inflow of zinc, which reduced the height of the sprouts by 1.2 times and the length of the leaf blade by 1.4 times. It is concluded that differences in cultures in need of Mo, Zn, Cu affect the peculiarities of their response to toxic concentrations of nutrients in the food system. It is proposed to apply estimates of levels of man-made contaminated areas with heavy metals and trace elements in the preparation of areas for agricultural activities in modern anthropogenic conditions.

The Response of Three Barley Cultivars to Cumin Extract at Different Soaking Times and the Identification of the Active Compounds Using GCMS

The research was carried out at the Agricultural Technical College / Mosul, to study the effect of cumin extract on barley culture with three factors, the first is (comparator and cumin extract), the second is the duration of soaking (6 and 12) hours, and the third is barley varieties (local, rayhan, zanbaqa), using the design of (CRD) and three replicates. At the end of the research, the data were recorded and analyzed according to the SAS program, and the different averages were distinguished by different alphabets, and the results were: Cumin extract was significantly superior to the control treatment in all studied traits, except for the number of roots. The duration of (12) hours was significantly superior to the duration of (6) hours in the wet and dry weight of the seedling. The barley zanbaqa cultivar outperformed the local and rayhan cultivars in all the studied traits. The interaction between cumin extract and the duration of (12) hours achieved significant superiority in all the studied traits. The interaction between cumin extract and zanbaqa cultivar was significantly superior in seedling wet weight, root length and vegetative length. The interaction between the period (12) hours and the zanbaqa variety caused a significant superiority in all the studied traits. The interaction between cumin extract, duration (12) hours, and zanbaqa cultivar was significantly superior to the rest of the interactions in wet and dry weight and root length.. The active compounds separated from the aqueous extract of cumin were diagnosed by GCMS and it was found that there are 9 compounds, 2 of which are phenolic and 7 of which are fatty acids.

The emerging problem in cereal crops in North-Eastern Tunisia: The cereal leaf beetles Oulema spp. (Coleoptera; Chrysomelidae; Criocerinae) dynamic populations and infestation rate

Cereals are attacked by several pests which reduce their yield and cause important losses. The Cereal Leaf Beetles (CLB) are emerging pests on cereals responsible of considerable damages. Oulema spp. (Coleoptera; Chrysomelidae; Criocerinae) populations and their infestation rates were evaluated on barley culture. Obtained results showed that cereal leaf beetles colonized the two barley plots (P1 and P2) in the same way during the survey period unless P1 was attacked earlier than P2 due to the quick development of plants as a consequence of the suitable climate conditions and the soil structure. Highest infestation rates reached values about 72% and 70% for P1 and P2 respectively. Then, they tended to decrease approaching hot season. Cereal leaf beetles prefer a humid space with fresh vegetation without chemical applications.

Zinc Plant Uptake as Result of Edaphic Factors Acting.

The influence of soil characteristics on the lability and bioavailability of zinc at both background and phytotoxic concentrations in Albic Retisol soil (Loamic, Ochric) was studied using various methods. Ranges of insufficient, non-phytotoxic, and phytotoxic zinc concentrations in soil solutions were established in an experiment with an aqueous barley culture. It was experimentally revealed that for a wide range of non-toxic concentrations of Zn in the soil corresponding to the indicative type of plant response, there was constancy of the concentration ratio (CR) and concentration factor (CF) migration parameters. As a result, a new method for assessing the buffer capacity of soils with respect to Zn (PBCZn) is proposed. The transformation processes of the chemical forms and root uptake of native (natural) zinc contained in the Albic Retisol (Loamic, Ochric) through the aqueous culture of barley were studied using a cyclic lysimetric installation and radioactive 65Zn tracer. The distribution patterns of Zn(65Zn) between different forms (chemical fractions) in the soil were established using the sequential fractionation scheme of BCR. The coefficients of distribution and concentration factors of natural Zn and 65Zn, as well as accumulation and removal of the metal by plants were estimated. The values of the enrichment factor of natural (stable) Zn contained in sequentially extracted chemical fractions with the 65Zn radioisotope were determined and the amount of the pool of labile zinc compounds in the studied soil was calculated.

Influence of stubble biodestructor on soil microbiological activity and grain yield of winter wheat (Triticum aestivum L.)

The aim of the work was to improve soil fertility and increase the yield of winter wheat using the stubble biodestructor by activating the microbiological activity of the soil. The experimental studies were on the research field of Mykolayiv National Agrarian University (Ukraine). After harvesting the precursor cultures of spring barley and peas the post-harvest residues of these crops were treated with a stubble biodestructor. After treatment of crop residues of spring barley and pea by the stubble biodestructor in the soil layer of 0 up to 20 cm the quantity of cellulose-destructive microorganisms increased by 27.9·105 up to 36.0·105 cfu/g of soil depending on the predecessor culture and the degree of degradation of these residues increased by 31.4 up to 45.1%. The number of nitrogen fixators in the 0-10 cm soil layer grew under the action of treatment of crop residues of spring barley and peas by stubble biodestructor on 13.4 up to 14.1 ·106 cfu/g of soilor 30.3 up to 35.0%. At the same time, a somewhat large number of bacteria in the soil was determined by the processing of post-harvest residues of peas, which was due to the biological characteristics of this legume culture. The average for years of researches at cultivating of winter wheat after spring barley using the stubble biodestructor the grain yield increased by 0.45 t ha–1, or 20.9%, and after pea it increased by 0.67 t ha–1 or 18.8% compared to the treatment variant of stubble just with water.

Structural Equation Modeling (SEM) Analysis of Sequence Variation and Green Plant Regeneration via Anther Culture in Barley.

The process of anther culture involves numerous abiotic stresses required for cellular reprogramming, microspore developmental switch, and plant regeneration. These stresses affect DNA methylation patterns, sequence variation, and the number of green plants regenerated. Recently, in barley (Hordeum vulgare L.), mediation analysis linked DNA methylation changes, copper (Cu2+) and silver (Ag+) ion concentrations, sequence variation, β-glucans, green plants, and duration of anther culture (Time). Although several models were used to explain particular aspects of the relationships between these factors, a generalized complex model employing all these types of data was not established. In this study, we combined the previously described partial models into a single complex model using the structural equation modeling approach. Based on the evaluated model, we demonstrated that stress conditions (such as starvation and darkness) influence β-glucans employed by cells for glycolysis and the tricarboxylic acid cycle. Additionally, Cu2+ and Ag+ ions affect DNA methylation and induce sequence variation. Moreover, these ions link DNA methylation with green plants. The structural equation model also showed the role of time in relationships between parameters included in the model and influencing plant regeneration via anther culture. Utilization of structural equation modeling may have both scientific and practical implications, as it demonstrates links between biological phenomena (e.g., culture-induced variation, green plant regeneration and biochemical pathways), and provides opportunities for regulating these phenomena for particular biotechnological purposes.

Impact of Ascorbate-Glutathione Cycle Components on the Effectiveness of Embryogenesis Induction in Isolated Microspore Cultures of Barley and Triticale.

Enhanced antioxidant defence plays an essential role in plant survival under stress conditions. However, excessive antioxidant activity sometimes suppresses the signal necessary for the initiation of the desired biological reactions. One such example is microspore embryogenesis (ME)—a process of embryo-like structure formation triggered by stress in immature male gametophytes. The study focused on the role of reactive oxygen species and antioxidant defence in triticale (×Triticosecale Wittm.) and barley (Hordeum vulgare L.) microspore reprogramming. ME was induced through various stress treatments of tillers and its effectiveness was analysed in terms of ascorbate and glutathione contents, total activity of low molecular weight antioxidants and activities of glutathione–ascorbate cycle enzymes. The most effective treatment for both species was a combination of low temperature and exogenous application of 0.3 M mannitol, with or without 0.3 mM reduced glutathione. The applied treatments induced genotype-specific defence responses. In triticale, both ascorbate and glutathione were associated with ME induction, though the role of glutathione did not seem to be related to its function as a reducing agent. In barley, effective ME was accompanied by an accumulation of ascorbate and high activity of enzymes regulating its redox status, without direct relation to glutathione content.

Оцінка біологічної ефективності перспективних домінантних штамів бактерій ризосфери ячменю ярого

An important task of modern agricultural production is the creation of new environmentally friendly agricultural technologies aimed at increasing the productivity of crops. Spring barley is an important forage crop, which occupies a significant place in the balance of concentrated feed. Therefore, our study is quite relevant today, given the trend towards the transition to organic farming and the development of biological fertilizers. The aim of the study was to determine the efficiency of inoculation with dominant strains of rhizosphere bacteria Phyllobacterium ifriqiyense 1 and Bacillus methylotrophicus 10 seeds of spring barley and physiological parameters of growth and development of the culture in model conditions. The task of the study is to determine the titer of viable bacteria, exposure of spring barley seeds in bacterial suspension, accounting for the growth of spring barley plants and fixing its biometric parameters after bacterization; determination of physiological parameters of plant growth and development in model conditions. Research methods – microbiological (direct calculation of viable colony-forming units using Goryaev's camera). Indicators of photosynthetic activity of the leaf were determined using the biophysical method of induction of chlorophyll fluorescence by a portable device "Floratest". The results of studies – the strain Phyllobacterium ifriqiyense 1 showed the maximum biological effect on the growth of test culture of barley (including dilution of culture fluid). It was found that treatment with bacterial suspensions of Phyllobacterium ifriqiyense 1 and Bacillus methylotrophicus 10 promotes the activation of the functions of the photosynthetic apparatus of barley plants in the laboratory. Prospects – rhizosphere microorganisms are important components of the environment in the early stages of ontogeny of cereals, so the use of dominant inoculating bacteria has scientific and practical significance in the optimization of agricultural production technologies.

Site-Directed Mutagenesis in Barley Using RNA-Guided Cas Endonucleases During Microspore-Derived Generation of Doubled Haploids.

In plant research and breeding, haploid technology is employed upon crossing, induced mutagenesis or genetic engineering to generate populations of meiotic recombinants that are themselves genetically fixed. Thanks to the speed and efficiency in producing true-breeding lines, haploid technology has become a major driver of modern crop improvement. In the present study, we used embryogenic pollen cultures of winter barley ( Hordeum vulgare ) for Cas9 endonuclease-mediated targeted mutagenesis in haploid cells, which facilitates the generation of homozygous primary mutant plants. To this end, microspores were extracted from immature anthers, induced to undergo cell proliferation and embryogenic development in vitro, and were then inoculated with Agrobacterium for the delivery of T-DNAs comprising expression units for Cas9 endonuclease and target gene-specific guide RNAs (gRNAs). Amongst the regenerated plantlets, mutants were identified by PCR amplification of the target regions followed by sequencing of the amplicons. This approach also enabled us to discriminate between homozygous and heterozygous or chimeric mutants. The heritability of induced mutations and their homozygous state were experimentally confirmed by progeny analyses. The major advantage of the method lies in the preferential production of genetically fixed primary mutants, which facilitates immediate phenotypic analyses and, relying on that, a particularly efficient preselection of valuable lines for detailed investigations using their progenies.

Grain barley starch as a gelling agent of nutrient media for cultivation of anthers and isolated embryos of H. vulgare L.

Aim. Determination the possibility of agar replacement with normal and waxy type starches produced from barley seeds in the nutrient media for spring barley haploid production. Methods. Anthers of spring barley line DH00-126 were inoculated on inductive media containing N6 macro-, MS micronutrients, organic supplements, maltose (9.0 %) and differed in solidifying agents (agar, starch from barley seeds or chemically modified starch D5a-1). Trophic capacities of barley starch were determined both in anther and embryo culture of barley. Results. It was determined that barley starch of waxy type was not suitable for solidifying of nutrient medium. Use of normal type barley starch (6.5 %) resulted in sufficient decrease in the frequency of green plant regeneration. At the same time, this modification had no effect on the number of morphogenic anthers. Barley starch was inferior to pea starch in the ability to support seedling growth in embryo culture in vitro. Conclusions. Barley starch of normal type has worse trophic capacities in comparison to pea starch in embryo culture. It was appeared barley starch to be a less suitable gelling agent of medium for spring barley haploid production in anther culture in vitro than agar and chemically modified starch D5a-1.
 Keywords: Hordeum vulgare L., anther culture in vitro, embryo culture in vitro, agar, barley starch.

Time of In Vitro Anther Culture May Moderate Action of Copper and Silver Ions that Affect the Relationship between DNA Methylation Change and the Yield of Barley Green Regenerants.

Plant anther culture allows for the regeneration of uniform and homozygous double haploids. However, off-type regenerants may appear as a result of so-called tissue culture-induced variation (TCIV). In addition, the presence of Cu2+ and Ag+ ions in the culture medium might influence the number of green plants. The regenerants were obtained via anther cultures of barley under varying Cu2+ and Ag+ ion concentrations in the induction medium during distinct time conditions. DArTseqMet markers were evaluated based on regenerants and donor plants and delivering data on DNA demethylation (DM) and de novo methylation (DNM) and changes in methylation (Delta). The number of green regenerated plants per 100 anthers (GPs) was evaluated. The Cu2+ and Ag+ ion concentrations moderated relationships between Delta and the number of green plants conditional on time of tissue cultures. Depending on the ions, moderated moderation is valid within the different time of anther culture. When the highest concentration of copper is analyzed, plant regeneration is possible under short ‘Time’ (21 days) of anther culture wherein Delta is negative or under elongated Time when Delta is positive. Under 21 days of culture, the highest concentration of silver ions and when Delta is negative, some regenerants could be evaluated. However, under high Ag+ concentration when Time of culture is long and Delta positive, the highest number of green plants could be obtained.

CG Demethylation Leads to Sequence Mutations in an Anther Culture of Barley Due to the Presence of Cu, Ag Ions in the Medium and Culture Time.

During plant tissue cultures the changes affecting regenerants have a broad range of genetic and epigenetic implications. These changes can be seen at the DNA methylation and sequence variation levels. In light of the latest studies, DNA methylation change plays an essential role in determining doubled haploid (DH) regenerants. The present study focuses on exploring the relationship between DNA methylation in CG and CHG contexts, and sequence variation, mediated by microelements (CuSO4 and AgNO3) supplemented during barley anther incubation on induction medium. To estimate such a relationship, a mediation analysis was used based on the results previously obtained through metAFLP method. Here, an interaction was observed between DNA demethylation in the context of CG and the time of culture. It was also noted that the reduction in DNA methylation was associated with a total decrease in the amount of Cu and Ag ions in the induction medium. Moreover, the total increase in Cu and Ag ions increased sequence variation. The importance of the time of tissue culture in the light of the observed changes resulted from the grouping of regenerants obtained after incubation on the induction medium for 28 days. The present study demonstrated that under a relatively short time of tissue culture (28 days), the multiplication of the Cu2+ and Ag+ ion concentrations (‘Cu*Ag’) acts as a mediator of demethylation in CG context. Change (increase) in the demethylation in CG sequence results in the decrease of ‘Cu*Ag’, and that change induces sequence variation equal to the value of the indirect effect. Thus, Cu and Ag ions mediate sequence variation. It seems that the observed changes at the level of methylation and DNA sequence may accompany the transition from direct to indirect embryogenesis

Ecological and biological conformity of conditions of the brewing barley cultivation zone

The correspondence of agro-ecological and climatic factors of the external environment of the industrial zone of brewing barley to the biological requirements of barley culture has been analyzed. The peculiarity of brewing barley in the formation of the crop and its quality is characterized by the necessity of directing, in the process of photosynthesis, the accumulation of the carbohydrate component of the grain more than in the protein content. The important role of ensuring these requirements depends mainly on the PAR of the long-wavelength range, especially during the second half of the growing season, during the growth and development of the grain. At this time, an important factor in ensuring the brewing quality of barley is the moisture supply of soil moisture, as it depends on the growth process of the grain. The barley culture belongs to the early spring cereals. Due to the changes in climatic conditions, which is directly related to the zone of industrial brewing of barley by analysis of ten-year temperature data, the favorable conditions for the growth and development of barley, the conditions of sowing in early spring have been found. In particular, sowing time is actually possible 20-25 days earlier than traditional, this is the first and second ten days of March. Conducted trial reconnaissance crops in the first decade of March ensured the effective development of plants and the formation of crops favorable to meet the quality requirements for the cultivation of products for the production of malt. The vegetative period of development before the onset of the generative has increased in plants up to 45 days, which by itself is a rather positive component of the efficiency of cultivation technology according to the results of the analysis of climatic factors of the zone of industrial production of brewing barley. As a result of analytical studies the improvement of ecological and biological compliance of spring barley development for the period 2010-2019 has been revealed. Due to the early onset of heat in March, there was a need to make adjustments to certain elements of technology based on appropriate research to ensure effective implementation of the agro-ecological resource of the area. The urgent tasks, with the aim of balanced processes of spring barley development to energy conditions of the environment, are research with seeding rate, row spacing, depth of seeds wrapping, application of mineral fertilizers.

Anatomy and Biochemical Study of Collar Rot Resistance in Eggplant

Disease reaction of three eggplant varieties (BAUBegun-1, BAUBegun-2 and Dohazari G) to collar rot (Sclerotium rolfsii) at early flowering stage, as well as the anatomy and biochemical effects of the infection on the collar region of the plant was studied. The plants were inoculated following soil inoculation technique, using barley culture of the pathogen. All the varieties were infected, with percentage infection ranging from 62.50 to 100%. Varieties varied in percent mortality (0.00 - 100). Plants of the eggplant variety BAUBegun-2, although infected, all regenerated and were graded resistant. The varieties Dohazari G and BAUBegun-1 were graded as susceptible. Anatomy and biochemical constituents, namely total phenols, ascorbic acid, total sugar, reducing sugar and Ca-oxalate contents of the collar region were investigated. BAUBegun-2 was characterized with thick cuticle, thick epidermal cells, many trichomes and smaller intercellular spaces in the cortex which could have restricted the entry of S. rolfsii into the cell. A higher level of biochemical activities was observed in eggplant var. BAUBegun-2. There was a clear correlation between anatomical features and biochemical constituents, and collar rot incidence. Anatomical features and biochemical constituents, as detected to be responsible for the resistance, could be used for the development of superior variety with resistance to collar rot.

Isolated Microspore Culture in Barley.

Isolated microspore culture (IMC) is the most efficient way to produce large numbers of doubled-haploid (DH) barley plants in a short time. Yet, while IMC is more cost-efficient and less labor-intensive than anther culture, it is technically more complex and requires more experienced personnel if it is to yield its full potential. In part, this is because of multiple and important interactions that exist between factors at its many different phases, including genotype effects as well. When every phase is fine-tuned, the protocol that is presented below yields a useful number of DHs with almost all genotypes and can allow the production of up to 300 DH plants from a single F1 plant in just a few months.