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The present work is focused on the synthesis and detailed study of biopolymer phytagel and ionic liquid 1-ethyl-3-methylimidazolium tricyanomethanide (EMIm[TCM]) blended polymer electrolyte films for energy applications. Here, biopolymer phytagel-based polymeric films are synthesized with different concentrations of ionic liquid (EMIm[TCM]) using the solution cast technique. The synthesized films are characterized for their structural, electrochemical, and dielectric properties using different characterization tools i.e., XRD, FTIR, Electrochemical Impedance Spectroscopy, Linear Sweep Voltammetry, and Wagnor polarization technique. The film with 30wt% EMIm[TCM] shows a maximum conductivity of 3.64 × 10-4 S cm-1 and an electrochemical stability window of 3.1 V. The dielectric properties such as dielectric constant (κ), dielectric loss tangent (tanδ), relaxation time, and frequency are also studied for the prepared pure phytagel and phytagel/EMIm[TCM] polymeric films.

Agarwood (Aquilaria malaccensis Lamk.) is a forest product commodity with high economic value, but its availability in nature is decreasing due to deforestation and overexploitation. The availability of high-quality seedlings is necessary to meet the demand and conserve the sources of agarwood plants. Therefore, this study investigates the interaction effect between media types and 1-Naphthaleneacetic acid (NAA) concentrations on agarwood shoot development. It also aims to determine the best medium type and NAA concentration to stimulate agarwood shoot development. This research had two stages, namely the shoot induction and development. The shoot induction stage was conducted experimentally, using a completely randomized design (CRD) on a factorial treatment pattern of 2 factors i.e., the types of media and NAA concentrations. The shoots produced from the induction stage were cultured on Murashige-Skoog (MS) media with the same media types but without any NAA addition. Furthermore, the variables observed in both stages were the development of agarwood shoots, and the parameters measured included the number of shoots, number of leaves and shoot lengths. The results showed that the development of agarwood shoots was controlled by the type of medium used. Liquid MS medium supported with filter paper bridge produced the highest average number of shoots with 4.93 and 5.87 shoots explants-1 and length at 3.25 and 3.64 cm explant-1 in the induction and development stage, respectively. These findings will facilitate mass propagation of agarwood shoots, and in turn the availability of agarwood plantlets supports its conservation and production.

Abstract: 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.

Banana cultivation is an agricultural activity practiced in different regions and constantly subjected to abiotic stresses that limit its productivity. To treat the effect of these stresses research can be undertake by simulating them in vitro since it limit the effect of the external factor in the experiment. Therefore, the objective of this study was to simulate the compaction in banana plant cultivated in vitro using Phytagel. To realize the experiment, we used MS culture medium with two distinct consistency added in the testing tubes. In the bottom part was added 10 mL of culture medium with consistency of jellification: 1.8, 2.8, 3.8, 4.8 and 5.8 g L-1 of Phytagel. Over this culture medium was added 5mL of half MS with consistency standard 1.8 g L-1 of Phytagel. Posteriorly, the planting materials from cultivar Grand Naine, BRS Vitória and BRS Princesa were inoculated in the growth medium. After 30 days of culture the plant materials were submitted for agronomic and physiological evaluation. The result showed non-significant difference among the compaction factors on physiological parameters however variety Grand Naine presents better performance in this character. Besides variety Grand Naine increased the rate of photosynthesis under compaction. This behaviour probably occurred due to overcoming the effect of stress by the variety. Therefore, it can be concluded that the cultivar Grand Naine is superior to cultivars BRS Vitória and BRS Princesa since it produces superior performance on rate of photosynthesis, stomatal conductance, and transpiration under simulated compaction conditions that favor the accumulation of plant biomass.

Banana cultivation is an agricultural activity practiced in different regions and constantly subjected to abiotic stresses that limit its productivity. To treat the effect of these stresses research can be undertake by simulating them in vitro since it limit the effect of the external factor in the experiment. Therefore, the objective of this study was to simulate the compaction in banana plant cultivated in vitro using Phytagel. To realize the experiment, we used MS culture medium with two distinct consistency added in the testing tubes. In the bottom part was added 10 mL of culture medium with consistency of jellification: 1.8, 2.8, 3.8, 4.8 and 5.8 g L-1 of Phytagel. Over this culture medium was added 5mL of half MS with consistency standard 1.8 g L-1 of Phytagel. Posteriorly, the planting materials from cultivar Grand Naine, BRS Vitória and BRS Princesa were inoculated in the growth medium. After 30 days of culture the plant materials were submitted for agronomic and physiological evaluation. The result showed non-significant difference among the compaction factors on physiological parameters however variety Grand Naine presents better performance in this character. Besides variety Grand Naine increased the rate of photosynthesis under compaction. This behaviour probably occurred due to overcoming the effect of stress by the variety. Therefore, it can be concluded that the cultivar Grand Naine is superior to cultivars BRS Vitória and BRS Princesa since it produces superior performance on rate of photosynthesis, stomatal conductance, and transpiration under simulated compaction conditions that favor the accumulation of plant biomass.

Nhằm tạo ra giống mía có năng suất cao, phẩm chất tốt và có khả năng kháng mặn. Trong điều kiện in vitro, các cá thể mía được tái sinh sau khi xử lý đột biến được đánh giá lại trên 2 loại chất làm rắn (agar và phytagel) ở các nồng độ muối khác nhau từ 70 ÷ 160 mM. Phytagel đã được xác định là chất làm rắn phù hợp để đánh giá và chọn lọc các dòng mía có khả năng chịu mặn đáng tin cậy. Bên cạnh đó, đã chọn được những dòng mía có khả năng chịu mặn ở các ngưỡng muối khác nhau để khảo sát ở điều kiện trong nhà màng là D1 sử dụng nồng độ muối 160 mM, D2 sử dụng nồng độ muối 135 mM và D3 sử dụng nồng độ muối 120 mM. Qua các chỉ tiêu sinh trưởng như số lá, số đốt và chiều cao cây, cho thấy dòng mía D1 sinh trưởng và phát triển ổn định ở nồng độ muối 100 mM.

Experiments were conducted to compare the liquid medium with the media solidified with agar or phytagel. Selective subculturing and use of the embryo maturation medium supplemented with higher concentration of phytagel (0.5%; w/v) were also tested for reducing the vitrified embryos. Modified Eeuwens Y3 medium was used as the basal medium. By culturing the anthers on the medium solidified with phytagel (0.25%; w/v), direct embryo formation (86.7%) and embryo conversion (21.5%) were significantly increased. Plant regeneration efficiency of anther derived embryos or calluses developed in the liquid culture medium was extremely low (2.4%). Vitrification was further reduced by incorporating 0.5% (w/v) phytagel into the embryo maturation medium. Highest plant regeneration efficiency was obtained by exposing the embryos to 0.5% (w/v) phytagel for 21 days, which reduced vitrification by 42%. Furthermore, selective subculturing of the embryos was effective for reducing vitrification.

Successful acclimatization and ex vitro rooting are among the key factors reducing the cost of micropropagated plants. We compared the survival of seven Russian cultivars of raspberry (Rubus idaeus) after rooting in vitro and ex vitro. Rooted shoots adapted to nonsterile conditions much better than nonrooted ones, with survival rates of 81%–98% versus 43%–76%, respectively. We studied the effects of different combinations of plant-growth regulators and gelling agents added to a proliferation medium on ex vitro rooting of primocane-fruiting raspberry cultivar “Atlant”. Reducing the agar concentration from 8 to 6.5 g/L increased the multiplication rate, but caused shoot hyperhydricity. The highest survival rate (97.2%) was observed for shoots grown in a medium containing 0.2 and 0.1 mg/L IBA, and gelled with 5 g/L agar and 0.2 g/L Phytagel. The microshoot height at the multiplication stage did not correlate with the plant growth during acclimatization. The obtained results can be used in the commercial micropropagation of the raspberry.

This paper describes a protocol for the efficient vegetative propagation of Cleome rosea by somatic embryogenesis. Leaf and stem explants from nursery-grown seedlings of C. rosea were cultivated on Murashige and Skoog (MS) medium supplemented with indole-3-acetic acid (IAA), a -naphthaleneacetic acid (NAA), 4-amino-3,5,6-trichloropicolinic acid (picloram) or 2,4-dichlorophenoxyacetic acid (2,4-D). Nodular calli were produced from both explant types in the presence of 4.5 and 9.0 µM 2,4-D. Embryo development and maturation were achieved when calli from stem explants were transferred to media containing a ten-fold reduction of 2,4-D concentration initially used (0.45 and 0.90 µM). Leaf-derived calli did not form embryos with the same treatments. The highest frequency of embryogenic callus formation (85%) and number of embryo per callus (13.45 ± 2.8) were achieved during the first subculture on medium supplemented with 0.90 µM 2,4-D. Embryo conversion into plantlets was achieved following transfer to growth regulator-free MS medium solidified with 2 g.L-1 phytagel. An acclimatization rate of 53% was found three months after transfer to ex vitro conditions and the recovered plants presented a normal phenotypic aspect.O trabalho descreve um protocolo para a propagação in vitro de Cleome rosea por embriogênese somática. Explantes foliares e caulinares, obtidos de plantas germinadas sob condições in vivo, foram cultivados em meio de Murashige and Skoog (MS) suplementado com ácido 3-indolacético (AIA), ácido naftalenoacético (ANA), ácido 4-amino-3,5,6-tricloropicolínico (picloram) ou ácido 2,4-diclorofenoxiacético (2,4-D). Calos de aspecto nodular foram produzidos a partir de ambos os tipos de explante na presença de 4,5 e 9,0 μM de 2,4-D. O desenvolvimento e a maturação de embriões somáticos foram alcançados quando calos obtidos de explantes caulinares foram transferidos para meio de cultura suplementado com uma concentração de 2,4-D dez vezes menor do que aquelas utilizadas na indução do processo de calogênese (0,45 e 0,90 μM). Calos derivados de explantes foliares não produziram embriões ao serem submetidos a estes mesmos tratamentos. Os maiores valores de freqüência de calos embriogênicos (85%) e número médio de embriões por calo (13,45±2,8) foram alcançados durante a primeira subcultura em meio suplementado com 0,90 μM de 2,4-D. O processo de conversão dos embriões somáticos em plantas foi observado após transferência dos embriões para meio MS sem suplementação hormonal solidificado com 2 g.L-1 de fitagel. Três meses após a transferência para condições ex vitro a taxa de aclimatização alcançada foi de 53% e as plantas apresentavam um aspecto fenotípico normal.

Mycophagous soil bacteria are able to obtain nutrients from living fungal hyphae. However, with exception of the bacterial genus Collimonas, occurrence of this feeding strategy has not been well examined for soil bacteria. Evaluation of the importance of mycophagy in soil bacterial communities requires targeted isolation methods. In this study, we compared two different approaches to obtain mycophagous bacteria from rhizospheric soil: A short-term method based on baiting for bacteria that can rapidly adhere to fungal hyphae and a long-term method based on the enrichment of bacteria on fungal hyphae via repeated transfer. Hyphae-adhering bacteria were isolated, identified by 16S rDNA sequencing and tested for antifungal activity and the ability to feed on fungi as the sole source of carbon. Both methods yielded a range of mycophagous bacterial isolates with little overlap between the methods. We also found indications for feeding preferences among mycophagous bacteria. Our results provide evidence for mycophagy being an important growth strategy for rhizosphere bacteria.To our surprise, we found several potential plant pathogenic bacteria among the mycophagous isolates. We discuss the possible benefits that these bacteria might gain from being associated with fungi.