Establishment of an efficient explants surface disinfection protocol is essential for in vitro cell and tissue culture as well as germplasm conservation, such as the case of Grapevine (Vitis spp.) culture. In this research, different procedures for disinfection and regeneration of field-grown grapevine cv. ‘Flame seedless’ axillary buds were evaluated. The buds were disinfected using either NaOCl or allyl, benzyl, phenyl and 2-phenylethyl isothiocyanates. Two different media for shooting and four media for rooting were tested. Shoot and root development per buds were registered. The best disinfection procedure with 90 % of tissue survival involved shaking for 60 min in a solution containing 20 % Clorox with 50 drops/L Triton® X-100. These tissues showed the potential to regenerate a complete plant. Plant regeneration was conducted using full strength Murashigue and Skoog (MS) medium supplemented with 8 µM benzyl aminopurine for shoot induction and multiplication, whereas rooting was obtained on half strength MS supplemented with 2 mg L−1 of indole-3-butyric acid and 200 mg L−1 of activated charcoal. In this work, it was designed the protocols for obtaining sterile field-grown grapevine buds and in vitro plant development. This methodology showed potential to produce vigorous and healthy plants in 5 weeks for clonal grapevine propagation. Regenerated plants were successfully established in soil.

Cryopreservation is used for the long-term conservation of plant genetic resources. This technique very often induces lethal injury or tissue damage. In this study, we measured indicators of viability and cell damage following cryopreservation and vitrification-cryopreservation in Vitis vinifera L. axillary buds cv. "Flame seedless" stored in liquid nitrogen (LN) for: three seconds, one hour, one day, one week and one month; after LN thawed at 38 °C for three minutes. The enzymatic activity of catalase (CAT) and superoxide dismutase (SOD), as well as the amount of malondialdehyde (MDA), total protein and viability were assayed.

Wheat cultivation makes an important contribution to human nutrition. Trehalose synthesis plays a role in the tolerance to drought stress. A bifunctional TPS-TPP enzyme gene from yeast was used to obtain transgenic wheat plants to increase trehalose synthesis. Mature wheat embryos were transformed using pGreen rd29A::TPS1-TPS2 or pGreen 35S::TPS1-TPS2 constructs. The transgene presence in mature leaves of T3 plants was confirmed by sequencing a PCR fragment of the inserted transgene. Transgenic and NT plants were submitted to drought stress for eight days. Transformed wheat lines retained a higher relative water content than NT plants during drought stress, and the Rubisco activity was unaffected. Plants transformed with the 35S construct showed a lower photosynthetic rate and lower fructose 1–6-bisphosphatase (FBPase) activity during drought, suggesting that constitutive trehalose and sucrose synthesis caused a reduced ribulose 1,5-bisphosphate (RuBP) regeneration. Lines transformed with the rd29A promoter showed a higher photosynthetic rate after eight days of drought, as the RuBP regeneration was unaffected. Transgenic wheat plants had higher biomass and grain weight than NT plants after drought. These results suggest that trehalose synthesis improves photosynthesis during stress and induces changes in the activity of some Calvin-cycle enzymes, reflected in plant metabolism and growth.