Asexual Epichloë Fungi—Obligate Mutualists

Asexual Epichloë are obligate fungal mutualists that form symbiosis with many temperate grass species, providing several advantages to the host. These advantages include protection against vertebrate and invertebrate herbivores (i.e., grazing livestock and invertebrate pests, respectively), improved resistance to phytopathogens, increased adaptation to drought stress, nutrient deficiency, and heavy metal-containing soils. Selected Epichloë strains are utilised in agriculture mainly for their pest resistance traits, which are moderated via the production of Epichloë-derived secondary metabolites. For pastoral agriculture, the use of these endophyte infected grasses requires the balancing of protection against insect pests with reduced impacts on animal health and welfare.

Lactoferrin and plant resistance to phytopathogens

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Inbreeding depression and genetic variability in agricultural traits and resistance to phytopathogens in exotic maize populations

The effect known as depression by inbreeding refers to the reduction on the average value of quantitative traits, related to plant reproduction and physiology, due to the homozygosis of deleterious alleles. This study evaluated the inbreeding depression and the genetic variability of agricultural traits and of the resistance to phytopathogens in inbred families of two exotic maize populations. The experiments were done in the experimental area of the Universidade Federal de Goiás, Regional Jataí, in the second harvest 2015. Fifty and 40 FS1 of NAP5 and NAP7 populations, respectively, were evaluated interplanting one row with a mixture of base population at every ten plots to estimate depression by inbreeding of the traits evaluated. The experimental design was randomized blocks, with three replications. The following traits were evaluated: AP – plant height (cm), AE – ear height (cm), FM – male flowering (days), PQ – number of broken plants, AC – number of lodged plants, PG – kernel production (kg plot-1). The greatest estimates of depression by inbreeding in the agricultural traits were observed for kernel production, with values of 51.2 and 38.9% for the populations NAP5 and NAP7, respectively. Among the traits of resistance to phytopathogens, the greatest estimate was observed for the stunting complex, with values of -58.9% in NAP5 and -74.2% in NAP7. Both populations under study presented genetic potential to be used in breeding programs with recurrent selection and, after some selection cycles, lineages with good agricultural standard and resistance to phytopathogens can be obtained.

Influence of different methods of grafted grapes bacterization on the degree of their protection against phytopatogens at the open stratification

The conducted studies allow us to conclude that the complexes KMP-1 (Diazophyte, Phosphoenterin, and Biopolycid) and KMP-2 (Phosphoenterin, Biopolycid, Aurill, and Azotobacterin) in water dilution 1:10 can be recommended for varieties with increased resistance to phytopathogens during open stratification to protect grafted grape cuttings from phytopathogens, while applying partial (apical) bacterization. The effectiveness of these microbial complexes is of the same standard as the action of the traditional chemical antiseptic Chinosolum at a concentration of 0.5 %.

Agrobacterium-mediated transformation of potato with human lactoferrin gene

Aim. Obtaining of the new Ukrainian potato cultivars with complex resistance to phytopathogens. Methods. Agrobacterium-mediated transformation of potato cultivars Vernisage and Zarevo with human lactoferrin gene possessing antimicrobial activity was carried out. For transformation, supervirulent A. tumefaciens strain EHA 105 with hLf gene and gene for the resistance to kanamycine was used. Selection was carried out for 3 months on MSK-S1 and MSK-S2 media supplemented with 100 mg/l kanamycine. Integration of lactoferrin gene in transgenic plant lines was confirmed by polymerase chain reaction with specific for hLf gene primers. Results. After selection, potato lines with the resistance to kanamycine were obtained. The transgenic potato lines with integrated into their genomes hLf gene were obtained. Integration of lactoferrin gene was confirmed for 1 line of Zarevo cultivar and 3 lines of Vernisage cultivar. Transformation frequency was of 6.8% for cv. Vernisage and 6.25% for cv. Zarevo. Conclusions. Selected potato lines would be used in further studies on their resistance to bacterial and fungal pathogens. Keywords: human lactoferrin gene hLf, Solanum tuberosum, Agrobacterium-mediated transformation, transgenic plants.