Salt stress is one of several major abiotic stresses that affect plant growth and development, and there are many evidences that silicon can ameliorate the injuries caused by high salinity. This study presents the results of an assay concerning: (1) the effect of in vitro NaCl-induced salt stress in cape gooseberry plants and (2) the possible mitigating effect of silicon in saline conditions. For that, nodal segments were inoculated in Murashige and Skoog (MS) medium under salinity (0.5 and 1.0% NaCl) with different silicic acid concentrations (0, 0.5 and 1.0g L-1). Phytotechnical characteristics, photosynthetic pigments content, and leaf anatomy were evaluated after 30 days. Shoot length, root length, number of leaves and buds, fresh and dry weight, pigment content, stomatal density and leaf blade thickness were drastically reduced by increased salt level. The supply of silicon (1.0g L-1) has successfully mitigated the effect of salinity at 0.5% NaCl for chlorophyll, carotenoids, stomatal density and leaf blade thickness. When salt stress was about 1.0%, Si was not effective anymore. In conclusion, we affirmed that, in in vitro conditions, salt stress is harmful for cape gooseberry plants and the addition of silicon showed effective in mitigating the saline effects of some features.

-The objective of this work was to evaluate the effects of the solidifying agents agar and phytagel and of activated charcoal on the in vitro cultivation of two maná cubiu (Solanum sessiliflorum) varieties: Thaís and Santa Luzia. The phytotechnical characteristics analyzed included number of leaves, number of roots, shoot and root length, and fresh matter of shoot and root. Regardless of the variety, phytagel was superior to agar as a culture medium. A greater number of leaves and longer shoots were observed in the Santa Luzia variety, in the absence of charcoal. The Thaís variety showed longer shoots and roots in the presence of charcoal.

The addition of silicon is known to produce satisfactory results in several types of plant cultures. However, there are no reports on the effects of addition of silicon to yam (Dioscorea spp.) micropropagation culture medium. The objective of the present study was to evaluate the effects of different silicon concentrations and sources on the growth characteristics of yam plants cultivated in vitro.Three sources of silicon were tested: potassium silicate, calcium silicate, and sodium silicate, each at concentrations of 0.0, 0.5, 1.0, and 2.0 mg L -1 , in all possible combinations. The experimental design was entirely randomized in a 3 × 4 factorial scheme with four replicates and twelve plants per treatment. The 2 mg L -1 sodium silicate supplement yielded the highest number of leaves (7.0) whereas the 1 mg L -1 sodium silicate produced the longest shoots (4.02 cm). Calcium silicate and potassium silicate yielded the highest fresh weight (0.2835 g and 0.2627 g, respectively). Overall, silicon promotes better plant development, with calcium silicate yielding the highest fresh weight. For in vitro yam cultivation, sodium silicate concentrations ranging between 1-2 mg L -1 are ideal.

The objective of this work was to evaluate the effects of temperature and osmotic agents on the in vitro conservation of Cape gooseberry (Physalis peruviana). Temperatures at 18 and 25°C, as well as the osmotic agents sucrose, mannitol, and sorbitol were tested. A short-term in vitro conservation of Cape gooseberry can be achieved at 18°C, using 30 g L-1 sucrose.

The biotechnological interest in genus Physalis has increased in the last decades, however, there are still few micropropagation studies of this genus. The objective of this study was to evaluate P. angulata photoautotrophic and photomixotrophic micropropagation with gas exchange under seven light spectra and five concentrations of sucrose. Lighting were yellow, blue, white, red, green, red + blue LEDs and natural light filtered by mesh. Sucrose concentrations were 0, 7.5, 15, 22.5 and 30 g.L-1. Phytotechnical, anatomical features and photopigment contents were evaluated through stem and root segment length, leaf number, leaf area, chlorophyll a and b contents, carotenoids, adaxial epidermis, palisadic and spongy parenchyma and abaxial epidermis. The data were compared by Scott-Knott's mean test and principal components analysis using the R software. Comparing the variables within lighting types, it was observed that only the screen treatment, screen-filtered natural illumination, obtained assessment in all variables. Comparing the levels of sucrose, it was observed that the treatment 15 g.L-1 sucrose obtained the highest number of averages with maximum evaluation. It was concluded that the natural light filtered by screen with 50% of shading allowed the photoautotrophic micropropagation of P. angulata. Better development results were observed in photomixotrophic micropropagation with 15 g.L-1 of sucrose.

Cape gooseberry (Physalis peruviana L.) cannot tolerate high levels of salinity. Salt stress is one of the most damaging abiotic stresses that affects plant development. However, there are some evidences that silicon (Si) can act as a mitigating agent of environmental stresses. Towards understanding the stress using tissue culture, we investigated the effect of in vitro NaCl-induced salt stress in cape gooseberry and the potential mitigating effect provided by Si. Nodal segments were inoculated in MS medium with different combinations of NaCl concentrations (0.5 and 1.0% NaCl) and silicic acid (0.0, 0.5, and 1.0 g L -1 ). The experimental design was completely randomized, in a factorial design with a control treatment [(2x3) + 1], totalizing 7 treatments. The control treatment consisted of an additional treatment without the addition of any of the factors. Isoenzyme activity, proline content, CO 2 level and biological activity were assessed after 30 d. We found an increase in all antioxidant enzymes (SOD, CAT and POD) activities when salt stress was imposed, indicating that the plant has an efficient system to protect itself against stress. Among these enzymes, Si played a mitigating role only in POD activity. In relation to other evaluated enzymes, NaCl enhanced the EST and MDH activities, followed by a subsequent decrease in MDH. Si showed different performances according to the concentration of NaCl. Electrophoretic analysis represented by bands illustrated these behaviors. Proline content increased as salinity increased, and Si effect was observed by increasing the levels of this amino acid. High CO 2 level was found at the concentration of 1.0% NaCl, and Si contributed to decrease this variable to normal levels. The reduction in the respiratory rates may contribute to the allocation of carbon to other chemical reactions such as the synthesis of new tissues. Salt stress also increased the biological activity of leaves and there was no effect of Si for this variable. We conclude that salt stress causes a great damage to in vitro-grown cape gooseberry plants and the addition of 1.0 g L -1 Si can ameliorate that damage for some characteristics. However, more studies are necessary since the physiological changes played by Si have been poorly understood for dicots.

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Physalis alkekengi is an ornamental plant that can also be used as a medicinal plant due to its anti-inflammatory, bactericidal, antitumor and fungicidal properties. Polyploidization can be an important tool in the genetic improvement of this species. The objective this work was to obtain tetraploids in vitro and to evaluate the phytotechnical traits of P. alkekengi. For this, nodal segments of P. alkekengi var. Franchettii were inoculated into petri dishes containing 100 ml of MS medium supplemented with colchicine at concentrations 0; 0.04; 0.08; 0.12; and 0.16% and kept in the dark for 24 and 48h. After the respective treatment periods with colchicine the segments were inoculated into test tubes. The tetraploids were identified by flow cytometry and classical cytogenetics. In vitro seedlings were measured: root length, nodal segment length, leaflet number and total leaf area. In the acclimatization phase, the area of ​​the second leaf and total leaf, petiole radius, stem length, fruit weight with calyx, without calyx, fruit diameter, number of seeds and brix of the pulp were evaluated. Chlorophyll a, chlorophyll b, total chlorophyll, total carotenoid, total chlorophyll / total carotenoid ratio and chlorophyll a / b ratio were also estimated. The treatment that most produced tetraploid seedlings was with 0.08% colchicine per 24h. No significant difference was observed in 7 (seven) variables, these being all variables of photopigments, stem diameter (steam) and brix. In general, diploid (2x) plants were better in 9 (nine) while tetraploid seedlings were better in 6 (six) of the phytotechnical variables. It was concluded that the MS medium supplemented with 0.08% colchicine for 24 h allowed P. alkekengi tetraploides to be obtained with better phytotechnical qualities.