plant breeding

In this research, the seeds of 12 sugar beet hybrids along with four control genotypes were planted in microplot conditions. After evaluating the roots against Rhizoctonia solani AG 2-2, the six genotypes that had the lowest amount of fungal infection were selected and tested for their reaction to Rhizomania virus disease. After examining ten soil samples from the farms of Kermanshah province and microplots located in Mahidasht research station, the contamination of the microplots of the experimental site with Rhizomania was confirmed based on serological and molecular methods. The seeds of six selected genotypes were planted in sterile soil and the seedlings were transferred to the microplate at the four-leaf stage. After harvesting, the roots were evaluated for BNYVV contamination using the ELISA method and based on Duncan's comparative test, they were divided into three groups. In general, due to the favorable resistance of the hybrid genotype (SB36*7112)* S1-92309 to both diseases, the use of the parents of this hybrid is suggested to continue for breeding experiments.

  Plant pathogens, insects and weeds contribute to more than 30% of crop losses annually. Toxic chemical bactericides have been extensively used to control plant pathogenic bacteria. These chemicals pose a health threat to humans and the environment and eventually lead to resistance of pathogens. Hence, breeding cultivars resistance to bacterial pathogens is a valuable and sustainable solution. Antimicrobial peptides (AMP) are a part of the immune system of all living organisms, including plants, to combat pathogenic bacteria. Hairy roots (HRs) system is a valuable tool to produce and evaluate the activity of AMPs in planta. The aim of this study was to produce a Dermaseptin B1 (Drs-B1) recombinant AMP in transgenic tobacco HRs using Agrobacterium rhizogenes and test its antibacterial activities.
Material and The DNA encoding sequence of a Drs-B1 peptide of a frog was codon optimized based and synthesized in the pGSA1285 expression vector under the control of 35S CaMV promoter (×3). A gene cassette containing the Drs-B1 gene was introduced to tobacco roots by Agrobacterium rhizogenesis mediated transformation. The transgenic HRs were confirmed by molecular methods. Antimicrobial activity of the protein extracts from transgenic HRs showed that the recombinant protein was able to prevent Pectobacterium carotovorum, Erwinia amylovora and Xanthomonas citri plant pathogenic bacteria growth. The anti-bacterial effects of Drs-B1 peptide against plant pathogenic bacteria were in the order of X. citri> E. amylovora >P. carotovorum. The peptide present in transgenic DrsB1-expressing HRs clones inhibited devastating plant pathogenic bacteria growth, suggesting that DrsB1 retains its antibacterial activity in plant cells. The results of present study may open promising opportunities to produce transgenic plants expressing antimicrobial peptides resistance to plant pathogens