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The current article presents the results of the influence of lighting conditions on the morphogenetic potential of Ipomoea batatas (L.) microcuttings in vitro. The studied objects were 4 sweet potato cultivars - Jewel, Purple, Porto Rico, Vinnitsa pink. Microcuttings of I. batatas were cultivated in vitro. We used nutrient medium with mineral salts (according to the prescription of Murashige and Skoog (MS)) and medium only with distilled water (without mineral salts). All nutrient media contained sucrose 2% and agar 0.7%. Hormones were not added to the nutrient media. We studied the influence of the different red (R) and far red (FR) ratios, as well as the red and blue light spectrum on the formation of microshoots and the root system. It was shown that the lighting regimes (R and FR ratio) had a stimulating effect on the roots and shoots growth regardless of the medium composition. Moreover, significant results were obtained under conditions of complete nutrition (mineral salts according to MS) in contrast to the control treatment (fluorescent lamps) and the treatment without salts. The best results were obtained at the R=FR treatment. This light treatment can be recommended for inclusion in the technology of clonal micropropagation of sweet potato. When red and blue spectra were added to normal illumination in different proportions, it did not lead to an increase in the morphogenetic potential of cultivated explants. The growth rate (μ) of the main shoot from axillary buds was about 2 times less than in the control treatment.

Fusarium oxysporum fungus is the pathogen that causes wilts or root and crown rots on many economically important field crops, causing significant losses to agricultural production. The use of plant extracts to control this fungus is an alternative to synthetic fungicides. Black cardamom (Amomum tsao-ko Crevost et Lemairé), which belongs to the monophyletic Zingiberaceae family, is a valuable medicinal plant in Vietnam. The antifungal activity of black cardamom seed extract has been reported in several previous studies. This study aimed to determine the antifungal activity of black cardamom extracts against the F. oxysporum fungus. The fungicidal effects of black cardamom extracts (including ethanol extract of leaf, seed, rhizome + root, and pseudo-stem) concentrations of 50 and 100 mg/L were investigated. Results indicated that the black cardamom extracts had different fungicidal effects on the growth of F. oxysporum mycelium. A significant inhibitory effect on the growth of F. oxysporum mycelium was obtained using the seed extract at a concentration of 100 mg/L. In addition, in the variant with the use of the extract obtained from the seeds, the lowest indicator of the specific growth rate (m) of the fungus was observed. The antifungal components from black cardamom plant could be used in developing novel fungicides (biopesticides) for the diseases caused by F. oxysporum.

Cardamom (Amomum tsao-ko Crevost & Lemarié) belongs to the genus Amomum Roxb. (Family: Zingiberaceae), is widely used as a flavoring and spicy ingredient in many traditional Vietnamese dishes; furthermore, it is also used in many traditional Vietnamese remedies to treat digestive ailments, malaria, bad breath, tooth decay, etc. Due to the presence of hard seed coat, cardamom has low seed germination potential. Therefore the aims of the present investigation were undertaken to study the effect of different sterilization agents, mechanical scarification, and various culture media on germination parameters of cardamom seeds. From there, an efficient in vitro cardamom seed germination protocol allows for a high germination rate and provides efficient production of high-quality sterile seedlings was described. Intact seeds were removed from aril and were soaked in warm water for 8 hours before sterilization; in the next step, they were disinfected in 0.1% mercuric chloride for 10 minutes and rinsed 4-5 times with sterile distilled water; then, they were scarified manually by cutting 1-1.5 mm of the seed coat at the opposite site of hilum by a sterile scalpel; lastly, they were inoculated onto MS medium diluted to 1/16 concentration at 25±2°C under a 16 h-photoperiod in cool white fluorescent light (2000-2500 lux). With this procedure, on average more than 33.33% of the seeds germinated after 90 days of culture, germination mean time (GMT) is 43.98 days, and germination rate index (GRI) is 0.1917.

Presents the results of years of research of cell selection of safflower varieties Krasa Stupinskiy for resistance to Fusarium oxysporum. The studies were performed on well proliferating callus tissue obtained from cotyledon leaves and hypocotyl segments isolated from sterile safflower seedlings. The culture filtrate (CF) of the pathogen (Fusarium oxysporum) in concentrations of 5%, 10%, 20% and 50% was used as a selective factor. Toxicity of CF was determined by germination of seeds, as well as by the growth of callus tissue. It was found that the culture filtrate in different concentrations has a toxic effect on the biometric parameters of safflower seedlings and on the growth of callus tissue. Moreover, with an increase in the concentration of CF phytotoxic effect is enhanced, and at a concentration of 100% there is a complete inhibition of seed germination. The optimal concentration of CF for cell selection is 15%. Adaptation of callus cells to the action of cf pathogen is caused by cell wall lignification. The resulting plants-regenerante who undergo further testing.

The results of cultivation of Cichoriumintybus L. in culture in vitro are presented. It is shown that the processes of morphogenesis are significantly influenced by growing conditions, in particular, the hormonal and mineral composition of the nutrient medium, as well as lighting modes. Callus tissue was obtained from leaf explants isolated from C. intybus plants. Leaf segments were cultivated on a nutrient medium containing mineral salts according to the MS prescription, as well as auxins - indolyl-3-acetic (IAA), naphthylacetic (NAA) and 2,4-dichlorophenoxyacetic (2,4-D) acids at a concentration of 5.5 - 9.5 mg / l in combination with cytokinin 6-benzylaminopurine (BAP) - 2 mg / l. The formed tissue was transplanted onto a fresh nutrient medium every four weeks, taking into account the color and consistency. Callus growth was determined by weighing in a laminar box at the beginning and end of the passage (mg). Callus tissue was cultured on agar nutrient medium in Petri dishes. Then they were placed in opaque grow tents with radiation aligned with the flux density of photosynthetic photons and different ratios of its levels in the region of 660 nm (R - red) and 730 nm (FR - far red). The control variant was placed in a light room, where illumination was created with white linear fluorescent lamps with an intensity of 150 µmol/m2s. At the end of the growing cycle, the color, texture of the callus and its growth were taken into account. It is shown that the process of callus formation depends on the auxin used and its concentration. The maximum increase in callus tissue was obtained on an MS medium containing IAA or NAA at a concentration of 8.5 mg/l. In the presence of NAA, a non–morphogenic callus was formed, and when using IAA, a morphogenic callus was formed. Studies have shown that the use of various lighting conditions (FR>R, FR=R, FRR variant, as well as on a nutrient medium containing IAA.