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Isolation of living sperm cells and in vitro fusion of Torenia fournieri gametes
81-85.Views:189In contrast to most angiosperms, Torenia contains a naked embryo sac and therefore has been considered since many years as an exciting model plant to study the double fertilization process of flowering seed plants. It is thus not surprising that the isolation of protoplasts from the female gametophyte has been reported already 20 years ago by Mol, the isolation of megaspores and megagametophytes has been published by the authors of this manuscript in 1996 and in 1999. The isolation of the male gametophyte and of sperm cells was published by the authors in 2004. The isolation of viable Torenia sperm cells is a crucial part of the elaboration of an in vitro fertilization system. Torenia sperm cells were isolated from in vivo — in vitro cultured pollen tubes. In this system pollen tubes first grow inside a cut style then follow their elongation in a solid isolation medium. The medium contained agarose in order to detain pollen tube contents. Released sperm cells and enzymatically isolated egg cells were collected and handled using glass micropipettes and transmitted to an electrofusion apparatus or polyethylene glycol containing media for fusion probes.
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Results in the determination of some Hosta varieties by the method of isoelectric focusing
90-92.Views:347Mass propagation of 5 newly introduced Hosta varieties was carried out by the method of micropropagation. Our aim was to determine exact variety specificity after the micropropagation period in the pattern of peroxidase isoenzymes by isoelectric focusing in pH 3-9 range and to determine that phenological phase of mother plant in which the isoenzyme pattern of mother plant can safely be comparable to the isoenzyme pattern of micropropagated descendants. The isoenzyme patterns of descendants were similar to the mother plants of the same hybrid lines. The older leaves seemed to be not so suitable for examination than newly developed ones despite of the higher activity of peroxidase enzymes. There were big differences in isoenzyme patterns of leaves in different phenological phases. With this quick and easy method Hosta varieties could be selected already in the very early stage of micropropagation.
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Effect of certain bentonite products on the temporal variation of elemental content in white wine
15-21.Views:46The 'terroir' character of wines can be shaped with certain technological elements such as bentonite fining. Bentonite is an agent used for the removal of thermolabile proteins in wines. However, during fining, the quantity of certain wine components can change, including the elemental composition of the wine. According to the recommendations of bentonite suppliers, wines should be racked off the bentonite fining sediment within 2-3 weeks. However, in winemaking practice, wines can remain on bentonite fining sediment for up to 1-4 months. One reason for this is that racking wines off the sediment has a negative impact on wine quality. Thus, it is a question of how much the later or earlier racking time can alter the elemental content of the wine. Our study aimed to examine the elemental content of wines treated with three different bentonite products sampled from over the bentonite fining sediment at various time points. Our investigation was conducted with the 2019 vintage white wine of the University of Debrecen. Fining was performed with three bentonite products: Nucleobent, BW200, and Granubent Poretec. The sampling schedule following fining was: 0 days - unfined control, 7th, 14th, 27th, 56th, and 85th days. The macro-, meso-, and microelement contents (P, K, Ca, Mg, S, Al, Na, B, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd, Ba, and Pb) of the wines were determined using ICP OES and ICP MS devices. Our results showed significant changes in the Al, Na, Cr, Fe, Co, Ni, Sr, Ba, Cu, and Pb contents of the wines depending on the sampling time. It is noteworthy that all three bentonite products increased the Al and Pb contents of the wines. For Fe, dynamic increases were observed over time with the BW200 product, reaching the threshold value of susceptibility to brakeage. However, from a winemaking technology perspective, it was favorable for the Cu content of the wines to decrease with both earlier and later racking times, for all bentonite products examined. Based on the elemental analyzes of the white wines studied, it can be concluded that racking of wines should be timed according to the recommendations of suppliers.
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Yield and fruit quality response to foliar application of biostimulants in an apple orchard
17-23.Views:505Nutrient supply plays an important role in fruit production technology. Among the methods of nutrient management, the application of foliar fertilization has become an essential tool to harmonize the vegetative and generative performance of fruit trees. This study was conducted to determine the effect of four foliar fertilizers (Bistep, brown juice, Trichoderma harzianum, Clonostachys rosea) on yield and fruit quality in an apple orchard with the cultivar ‘Pinova’, at the University of Debrecen in Hungary. Trees were trained to a slender spindle canopy with a spacing of 4 × 1 m. Treatments were applied five times during different phenological phases in 2021 and 2022. Based on our results, biostimulants had a positive effect on fruit yield and fruit quality, but extreme weather events also influenced the data. In 2021, the effect of the treatments on yield data could not be observed (10.1–13.5 kg/tree; 0.16–0.24 kg/cm²). However, in 2022, plants sprayed with Bistep, T. harzianum, and C. rosea reached 28.7–31.2 kg/tree (0.33–0.46 kg/cm²), while control trees produced only 19.8 kg/tree (0.20 kg/cm²). Fruit size development improved with an increase of 2–6 mm over the two years. Among the treatments, Bistep was able to enhance fruit surface coloration to a greater extent in 2021, as red skin color reached 44% for this foliar fertilizer, while control trees presented only 27%.
