Refrigerated storage period of Rhizophores for Yacon propagation / Períodos de armazenamento refrigerado de rizóforos para propagação de yacon

The yacon plant produces tuberous roots, used mostly for fresh consumption. This crop is propagated primarily via vegetative structures, called rhizophores. However, since these propagules have short periods of viability after harvest, storing them in cold chamber conditions may be a viable alternative to optimize yacon seedling production. The objective of this study was to test the effect of the refrigerated storage period of yacon rhizophores on seedling development. The experimental design was completely randomized, with eight replications, containing 30 useful plants per replication. Treatments were cold storage periods of propagative materials (35, 28, 21, 14, and 7 days) and a control (planting without storage). The results show that keeping rhizophores in cold storage under temperatures of 8 ºC (± 2 ºC) for a period between 21 to 35 days improves sprouting rates (speed and vigorousness), reducing seedling mortality and favoring initial yacon growth. The refrigerated storage for 21 and 35 days proved to be an alternative to achieve improved plant stand in production fields, reflecting in more uniform harvest, and minimizing the problem of seasonal availability of propagative material.Yacon, is known for its tuberous roots, which are consumed as functional food and is propagated mostly in the vegetative form, via propagules, so-called rhizophores. However, they are organs with little durability in its propagation form. Storing them in cold chamber conditions, can be a viable alternative for the seedlings production of the culture. The objective of this study was to verify the influence of the refrigerated storage period of yacon rhizophores in the initial plant development. The experimental design was completely randomized with eight replicates and six treatments and the rhizophores were place in the refrigerated storage for: 7, 14, 21, 28 and 35 days; and time zero (planting without storage). The results show that the rhizophores in the refrigerated storage in a temperature of 8 to 10°C, for a period between 21 to 35 days had better sprouting rate (speed and vigor), reducing mortality, which favored the initial yacon growth. The refrigerated storage between 21 and 35 days showed to be an alternative that resulted in a uniform plant stand in crops, also reflecting the uniformity in the harvest, and minimizes the problem of seasonality offering culture propagation material.

A yacon, conhecida por suas raízes tuberosas, que são consumidas como alimento funcional, é propagada em sua maioria na forma vegetativa, via propágulos, assim chamados de rizóforos. No entanto, são órgãos de pouca durabilidade na sua forma propagativa. Logo, o armazenamento dos mesmos em condições de câmara fria, pode vir a ser uma alternativa viável para a produção de mudas da cultura. Assim, objetivou-se com o presente trabalho, verificar a influência do período de armazenamento refrigerado dos rizóforos de yacon no desenvolvimento inicial das plantas. O delineamento experimental foi inteiramente casualizado com oito repetições e seis tratamentos constituídos pelos períodos de armazenamento refrigerado em que os rizóforos foram submetidos: 7, 14, 21, 28 e 35 dias; e o tempo zero (plantio sem armazenamento). Os resultados demonstraram que o armazenamento refrigerado dos rizóforos, em temperatura de 8 a 10 ºC, por um período entre 21 a 35 dias, proporcionou melhores índices de brotação (velocidade e vigorosidade), diminuindo a taxa de mortalidade, o que favoreceu o crescimento inicial da yacon. O armazenamento refrigerado entre 21 e 35 dias apresentou ser uma alternativa que resultou em maior uniformidade na formação do estande de plantas na lavoura, inclusive repercutindo na uniformidade de colheita, além de minimizar o problema de sazonalidade da oferta de material propagativo da cultura.

Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions / O investimento de tiro aumentado faz plantas invasivas exposição de vantagens de crescimento em altas condições de nitrógeno

Abstract Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

Resumo As alterações de recursos geralmente promovem invasões de plantas, suscitando preocupações quanto às conseqüências potenciais da deposição de nitrogênio (N); No entanto, não está claro se os invasores se beneficiarão da deposição de N mais do que com os nativos. O crescimento é um dos traços inerentes mais fundamentais das plantas e, portanto, os bons invasores podem ter vantagens de crescimento superiores em resposta a alterações de recursos. Comparamos o crescimento e a alocação entre plantas invasivas e nativas em diferentes regimes de N, incluindo controles (concentrações ambientais de N). Descobrimos que as plantas invasivas sempre cresceram muito mais do que as plantas nativas em diferentes condições de N, independentemente das análises baseadas em crescimento ou filogenia, e que o primeiro atribuiu mais biomassa aos rebentos do que o segundo. Embora N aumentou o crescimento de plantas invasivas, esse aumento não aumentou com o aumento da adição de N. Através das espécies invasivas e nativas, as mudanças na alocação da biomassa do extrato foram correlacionadas positivamente com as mudanças na biomassa da planta inteira; e a inclinação desse relacionamento foi maior em plantas invasivas do que plantas nativas. Essas descobertas sugerem que o aumento do investimento em lançamentos faz com que as plantas invasivas mantenham uma vantagem de crescimento em altas condições de N em relação aos nativos, e também destacar que a futura deposição de N pode aumentar os riscos de invasões de plantas.

De novo in vitro shoot morphogenesis from shoot tip-induced callus cultures of Gymnema sylvestre (Retz.) R. Br. ex Sm

BACKGROUND: Gymnema sylvestre is a medicinal woody perennial vine known for its sweetening properties and antidiabetic therapeutic uses in the modern and traditional medicines. Its over-exploitation for the therapeutic uses and to meet the demand of pharmaceutical industry in raw materials supply for the production of anti-diabetic drugs has led to considerable decline in its natural population. RESULTS: An efficient system of shoot bud sprouting from nodal segment explants and indirect plant regeneration from apical meristem-induced callus cultures of G. sylvestre have been developed on Murashige and Skoog (MS) medium amended with concentrations of cytokinins. Of the three growth regulators tested, N6-benzylaminopurine (BAP) was the most efficient and 2.0 mg L-1 gave the best shoot formation efficiency. This was followed by thidiazuron (TDZ) and kinetin (Kin) but, most of the TDZ-induced micro shoots showed stunted growth. Multiple shoot formation was observed on medium amended with BAP or TDZ at higher concentrations. The produced micro shoots were rooted on half strength MS medium amended with auxins and rooted plantlets acclimatized with 87% survival of the regenerates. CONCLUSIONS: The developed regeneration system can be exploited for genetic transformation studies, particularly when aimed at producing its high yielding cell lines for the anti-diabetic phytochemicals. It also offers opportunities for exploring the expression of totipotency in the anti-diabetic perennial vine.

Micropropagation of Calophyllum brasiliense (Cambess) from nodal segments / Micropropagação de Calophyllum brasiliense (Cambess) a partir de segmentos nodais

Abstract Micropropagation of Calophyllum brasiliense Cambess. (Clusiaceae) is a way to overcome difficulties in achieving large-scale plant production, given the recalcitrant nature of the seeds, irregular fructification and absence of natural vegetative propagation of the species. Cultures were established using nodal segments 2 cm in length, obtained from 1-2 year old seedlings, maintained in a greenhouse. Mercury chloride and Plant Preservative Mixture™ were used in the surface sterilizing stage, better results being achieved with Plant Preservative Mixture™ incorporation in culture medium, at any concentration. Polyvinylpyrrolidone, activated charcoal, cysteine, ascorbic acid or citric acid were added to the culture medium to avoid oxidation. After 30 days of culture, polyvinylpirrolidone and ascorbic acid gave better results, eliminating oxidation in most explants. For shoot multiplication, benzylaminopurine was used in concentrations of 4.4 and 8.8 µM in Woody Plant Medium, resulting in an average of 4.43 and 4.68 shoots per explant, respectively, after 90 days. Indole-3-butyric acid and α-naphthalene acetic acid were used to induce root formation, reaching a maximum rooting rate of 24% with 20µM α-naphthalene acetic acid. For acclimatization. the rooted plants were transferred to Plantmax® substrate and cultured in a greenhouse, reaching 79% of survival after 30 days and 60% after one year.

Resumo A micropropagação de Calophyllum brasiliense Cambess. (Clusiaceae) é uma maneira de superar dificuldades para sua produção em larga escala, devido à natureza recalcitrante das sementes, frutificação irregular e ausência de propagação vegetativa natural da espécie. Culturas foram estabelecidas utilizando segmentos nodais com 2 cm de comprimento, obtidos de plantas com 1 a 2 anos de idade, mantidas em casa de vegetação. Cloreto de mercúrio e Plant Preservative Mixture™ foram utilizados durante a etapa de desinfestação, com melhores resultados alcançados com a incorporação de Plant Preservative Mixture™ ao meio de cultura. Polivinilpirrolidona, carvão ativado, cisteína, ácido ascórbico ou ácido cítrico foram adicionados ao meio de cultura para evitar a oxidação dos explantes. Após 30 dias de cultivo, o uso de polivinilpirrolidona ou ácido ascórbico proporcionou melhores resultados, eliminando a oxidação na maioria dos explantes. Para multiplicação das brotações, benzilaminopurina foi usada em concentrações de 4.4 e 8.8 µM em meio WPM, resultando em uma média de 4.43 e 4.68 brotações por explante, respectivamente, após 90 dias. Ácido indol-3-butírico e ácido α-naftaleno acético foram usados para a indução de raízes, alcançando um enraizamento máximo de 24% com o uso de 20µM de ácido α-naftaleno acético. As plantas enraizadas foram transferidas para substrato Plantmax® e cultivadas em casa de vegetação, alcançando 79% de sobrevivência após 30 dias e 60% após um ano.

Effect of arbuscular mycorrhizal fungi on young vines in copper-contaminated soil

Abstract High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.

Plant Growth Promotion and Root Colonization by EPS Producing Enterobacter sp. RZS5 under Heavy Metal Contaminated Soil.

The heavy metal resistant bacterium isolated from field soil and identified as Enterobacter sp. RZS5 tolerates a high concentration (100-2000 mM) of various heavy metal ions such as Mn2+, Ni2+, Zn2+, Cu2+, CO2+ and Fe2+ when grown in such environment and produces exopolysaccharides (EPS). Here, we have demonstrated EPS production by Enterobacter sp. RZS5 during 60 h of growth in yeast extract mannitol broth (YEMB). The yield increased by two fold after the addition of 60 M of Ca2+; 50 M of Fe2+ and 60 M of Mg2+ ions in YEMB, and the optimization of physico-chemical parameters. EPS was extracted with 30% (v/v) of isopropanol as against the commonly used 50% (v/v) isopropanol method. EPS-rich broth promoted seed germination, shoot height, root length, number of leaves and chlorophyll content of wheat (Triticum aestivum) and peanut (Arachis hypogaea) seeds. The higher colony-forming unit of Enterobacter sp. in soil inoculated with EPS rich broth of Enterobacter sp. indicated the root colonizing potential and rhizosphere competence of the isolate. The FTIR spectra of the EPS extract confirmed the presence of the functional group characteristics of EPS known to exhibit a high binding affinity towards certain metal ions. This overall growth and vigour in plants along with the effective root colonization, reflected the potential of the isolate as an efficient bio-inoculant in bioremediation.

Chromium accumulation potential of Zea mays grown under four different fertilizers.

Chromium (Cr) contamination in soil is a growing concern in sustainable agriculture production and food safety. We performed pot experiment with chromium (30 mg/ soil) to assess the accumulation potential of Zea mays and study the influence of four fertilizers, viz. Farm Yard Manure (FYM), NPK, Panchakavya (PK) and Vermicompost (VC) with respect to Cr accumulation. The oxidative stress and pigment (chlorophyll) levels were also examined. The results showed increased accumulation of chromium in both shoots and roots of Zea mays under FYM and NPK supply, and reduced with PK and VC. While the protein and pigment contents decreased in Cr treated plants, the fertilizers substantiated the loss to overcome the stress. Similarly, accumulation of Cr increased the levels of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) indicating the enhanced damage control activity. However, these levels were relatively low in plants supplemented with fertilizers. Our results confirm that the maize can play an effective role in bioremediation of soils polluted with chromium, particularly in supplementation with fertilizers such as farm yard manure and NPK.

Mannitol-induced drought stress on calli of Trigonella foenum-graecum L. Var. RMt-303.

Different explants of fenugreek, T. foenum-graecum L. (Var. RMt-303), were compared for their callus induction and subsequent shoot regeneration capabilities on Murashige and Skoog media supplemented with different phytohormones in varying concentration. The highest percentage of callus induction frequency was observed in 1ppm benzylaminopurine (BAP). Maximum shoots were induced on media supplemented with 0.5ppm BAP using leaf and stem tissues as explants. However, root tissues showed only callusing with no subsequent shooting. Cotyledonary node responded better than hypocotyls in terms of shoot induction on media supplemented with thidiazuron (0.1ppm). The callus was subjected to drought stress as simulated by reduced water potential of growth media due to addition of mannitol. Calli could withstand -2 MPa water potential till 30 days indicating that the drought stress tolerance mechanisms are functional in this variety. Chlorophyll a and b and total chlorophyll, proline and total phenolic contents, total peroxidase and catalase activities increased under stress conditions suggesting the tolerance of callus to drought stress. However, ascorbate peroxidase, guaiacol peroxidase activities were found to decrease slightly. Malondialdehyde and H2O2 contents were found to decrease while only a slight disturbance was found in membrane stability index. These results underline the mechanisms that are crucial for drought stress tolerance in fenugreek.

In vitro regeneration and ploidy level analysis of Eulophia ochreata Lindl.

Various parameters including explant-type, medium compositions, use of phytohormones and additives were optimized for direct and indirect regeneration of E. ochreata, a medicinal orchid under threat. Protocorm-like-bodies (PLBs) proved to be the best explants for shoot initiation, proliferation and callus induction. Murashige and Skoog’s (MS) medium containing 2.5 mg L-1 6-benzylaminopurine (BAP), 1.0 mg L-1 kinetin (Kin) and additives (adenine sulfate, arginine, citric acid, 30 mg L-1 each and 50 mg L-1 ascorbic acid) was optimal for shoot multiplication (12.1 shoots and 7.1 PLBs per explant with synchronized growth), which also produced callus. Shoot number was further increased with three successive subcultures on same media and ~40 shoots per explant were achieved after 3 cycles of 30 days each. Additives and casein hydrolysate (CH) showed advantageous effects on indirect shoot regeneration via protocorm-derived callus. Optimum indirect regeneration was achieved on MS containing additives, 500 mg L-1 CH, 2.5 mg L-1 BAP and 1.0 mg L-1 Kin with 30 PLBs and 6 shoots per callus mass (~5 mm size). The shoots were rooted (70% frequency) on one by fourth-MS medium containing 2.0 mg L-1 indole-3-butyric acid, 200 mg L-1 activated charcoal and additives. The rooted plantlets were hardened and transferred to greenhouse with 63% survival rate. Flow-cytometry based DNA content analysis revealed that the ploidy levels were maintained in in vitro regenerated plants. This is the first report for in vitro plant regeneration in E. ochreata.

Histology of the regeneration of Paulownia tomentosa (Paulowniaceae) by organogenesis / Histología de la regeneración por organogénesis en Paulownia tomentosa (Paulowniaceae)

Paulownia tomentosa is a fast-growing tree species with a considerable economic potential because of its value for wood as well as its high biomass production, and elevated stress tolerance. The objective of the present study was to evaluate the development of adventitious buds in leaves obtained from four-week-old shoots of P. tomentosa, in order to identify the cells involved in in vitro adventitious bud development. Leaves (proximal halves with the petiole) from the first node were excised from four-week-old micropropagated shoots, and cultured on Murashige and Skoog medium, supplemented with 3% (w/v) sucrose, 0.6% (w/v) Sigma agar, 22.7µM thidiazuron (TDZ) and 2.9µM indole-3-acetic acid for two weeks, explants were then transferred to the same medium with 0.44µM N6-benzyladenine for another four weeks. Five explants were collected daily during the two first weeks in TDZ treatment. A total of 140 samples were processed. Most of the buds developed indirectly from the callus formed in the petiole stub, and they became visible after eight-ten days of culture, although some buds were also observed in the area of the laminar cut at the level of the veins. The first histological changes could be observed after two-three days of culture, with the dedifferentiation of some subepidermal and inner parenchyma cells, which exhibited a large, prominent nucleus, densely-stained cytoplasm and a high nucleusto-cell area ratio. Proliferation of these cells gives rise to meristemoid formation after seven-ten days of culture. Organized cell division in meristemoids allows the formation of bud primordia that emerged from the explants surface. The progressive structural differentiation of the apical meristem, leaf primordia, and procambium strands, led to formation of complete buds that were observed in the exterior of the explants after 10-15 days of culture. Direct development of buds from cells in the subepidermic and/or epidermic layers were observed ...

Paulownia tomentosa es un árbol de rápido crecimiento y con un gran potencial económico por su madera, su utilización para la producción de biocombustible, así como su alto rendimiento en la producción de biomasa y su elevada tolerancia al estrés. El objetivo del presente trabajo ha sido evaluar el desarrollo a nivel histológico de yemas adventicias en hojas de Paulownia tomentosa. Hojas del primer entrenudo de brotes de cuatro semanas cultivados in vitro, fueron cultivadas en medio de Murashige y Skoog complementado con 22.7µM tidiazuron y 2.9µM ácido indol acético durante dos semanas. Los explantos fueron posteriormente transferidos a igual medio con 0.44µM N6 -benciladenina durante otras cuatro semanas. Se recogieron cinco muestras diarias durante las dos primeras semanas de tratamiento en medio con TDZ, procesando un total de 140 muestras. La mayoría de las yemas se desarrollan indirectamente a partir del callo formado en la superficie de corte del pecíolo. Después de dos-tres días de cultivo se observan los primeros cambios histológicos, con la desdiferenciación de algunas células de las capas subepidérmicas y del parénquima interno. La posterior proliferación de estas células da lugar a la formación de los meristemoides después de siete-diez días de cultivo. La progresiva diferenciación de estos meristemoides da lugar a la formación de las yemas que son visibles al exterior a partir de los 10-15 días. En la superficie adaxial del pecíolo se observó la formación de yemas adventicias de forma directa. Este protocolo puede ser de gran utilidad para la determinación de las células más adecuadas para los procesos de transformación genética.

Large scale propagation of an exotic edible bamboo, Phyllostachys pubescens Mazel ex H. De Lehale (Moso Bamboo) using seeds.

For ex vitro propagation, seeds of P.pubescens were treated with different concentrations of gibberellic acid (GA3) and germination of seeds was tested both in plastic pots as well as by direct sowing in the nursery beds. Maximum seed germination was achieved when treated with 200 mgL–1 (w/v) GA3. For in vitro propagation, an exposure of nodal explants from in vitro raised seedlings to 0.2 mgL–1 1–phenyl–3–(1,2,3–thiadiazol–5–yl) urea and 1 mgL–1 kinetin supplemented medium for 30 days and thereafter to hormone free Murashige and Skoog basal medium resulted in axillary shoot proliferation. For rooting, in vitro raised shoots were exposed to MS medium containing 2 mgL–1 indole-3-butyric acid for 15 days and then shifted to hormone free medium. On an average, 2.8 shoots were obtained in 75% of the cultures within 4 weeks. Such in vitro raised plants were successfully hardened and shifted to field conditions.

Bioinformatics based structural characterization of glucose dehydrogenase (gdh) gene and growth promoting activity of Leclercia sp. QAU-66

Glucose dehydrogenase (GDH; EC 1.1. 5.2) is the member of quinoproteins group that use the redox cofactor pyrroloquinoline quinoine, calcium ions and glucose as substrate for its activity. In present study, Leclercia sp. QAU-66, isolated from rhizosphere of Vigna mungo, was characterized for phosphate solubilization and the role of GDH in plant growth promotion of Phaseolus vulgaris. The strain QAU-66 had ability to solubilize phosphorus and significantly (p < 0.05) promoted the shoot and root lengths of Phaseolus vulgaris. The structural determination of GDH protein was carried out using bioinformatics tools like Pfam, InterProScan, I-TASSER and COFACTOR. These tools predicted the structural based functional homology of pyrroloquinoline quinone domains in GDH. GDH of Leclercia sp. QAU-66 is one of the main factor that involved in plant growth promotion and provides a solid background for further research in plant growth promoting activities.

Establishment of an in vitro plantlet regeneration protocol for unique varieties of brinjal (Solanum melongena L.) var. Mattu Gulla and Perampalli Gulla.

Brinjal (Solanum melongena L.) var. Mattu Gulla (MG) and var. Perampalli Gulla (PG) are unique varieties with distinct flavour cultivated in Udupi, Karnataka State, and are exposed to several biotic and abiotic stresses. An efficient and reproducible in vitro regeneration method is required to expedite the manipulation of these brinjal varieties to cope up with stress by tissue culture and gene transfer methods. The present study, reports a rapid and efficient in vitro regeneration protocol for these two varieties. The in vitro growth response was studied on Murashige and Skoog (MS) medium supplemented with 2, 4-D, BAP and IAA, and the plantlets were regenerated efficiently from callus cultures of leaf, cotyledon and hypocotyl explants. Among the three explants, the hypocotyl explants were found to have better callus induction and multiple shoot regeneration. High frequency of shoot initiation was achieved from hypocotyl derived calluses in MS media with 2.0 mg/L BAP and 0.5 mg/L IAA in MG and PG. Efficient and rapid shoot proliferation, and elongation were noted in MS medium with 1.0 mg/L BAP and 0.3 mg/L GA3. The in vitro regenerated shoots produced healthy roots when they were cultured on MS medium supplemented with 0.5 mg/L IBA. A significant difference was observed in percentage of callus induction, number of shoots per callus, shoot elongation and number of hardened plantlets of MG and PG. MG showed maximum response in all stages of culture than PG. Hardening of plantlets in tissue culture was achieved in three weeks. The hardened plantlets were grown in pots for further acclimatization in green house and finally transplanted to experimental garden where they developed into flowering plants and produced mature fruits with viable seeds.

Multiplicação in vitro de segmentos apicais caulinares de segurelha (Satureja hortensis L. ) / In vitro multiplication of apical shoot segments of Summer Savory (Satureja hortensis L. )

O presente estudo teve por objetivo avaliar o efeito de BAP, na presença e ausência de ANA, sobre a multiplicação in vitro de segmentos apicais caulinares de Satureja hortensis. Os explantes foram isolados de plântulas germinadas in vitro e cultivados em meio nutritivo MS. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 2x5, correspondendo às concentrações de ANA (0 e 1 µM) e de BAP (0; 5; 10; 15 e 20 µM), com seis repetições, cada uma composta por três explantes. Para a porcentagem de explantes com brotações houve efeito significativo para o fator BAP, aumentando à medida que cresce a concentração da citocinina. A variável "número de brotos por explante" apresentou interação entre os fatores, havendo a maior formação de brotos na presença de ANA na faixa de 10 - 15 µM de BAP. Na presença da auxina, o maior valor ocorreu com 15 µM de BAP tendendo a diminuir independente da presença de ANA. O enraizamento dos segmentos apicais foi maior na presença de ANA e ausência de BAP, diminuindo com o aumento da citocinina. O número de folhas foi influenciado pela maior concentração de BAP sendo que a 15 µM foi observado o maior número, tendendo à queda com aumento da concentração. A concentração de 15 µM de BAP, independente de ANA, proporcionou os melhores resultados na multiplicação da espécie produzindo aumento de brotações e número de folhas, à exceção do enraizamento que foi influenciado pela auxina.

This study aimed to evaluate the effect of BAP in the presence and absence of NAA, on the in vitro multiplication of shoot apical segments of Satureja hortensis. The explants were isolated from seedlings germinated in vitro and cultured in nutrient medium MS. The experimental design was completely randomized in a 2x5 factorial arrangement, corresponding to the concentrations of NAA (0 and 1 µM) and BAP (0, 5, 10, 15 and 20 µM), with six replicates, each consisting of three explants. For the percentage of explants with shoots, there was no significant effect for the factor BAP, increasing as the concentration of BAP grows. The variable number of shoots per explant showed interaction between factors, with the highest shoot formation in the presence of NAA and BAP in the range of 10 -15 µM. In the presence of auxin, the highest value occurred with 15 µM BAP, tending to decline regardless of the presence of NAA. The rooting of the apical segments was higher in the presence of NAA and absence of BAP, decreasing with increasing cytokinin. Leaf number was influenced by the higher concentration of BAP, and the amount of 15 µMhadthe largest number, tending to decrease with increasing concentration. The concentration of 15 µM BAP, regardless of NAA, provided better results in the multiplication of the species, producing increased number of shoots and leaves, except for rooting, whichwas influenced by auxin.

A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub.].

A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

Plant regeneration from callus cultures of Vitex trifolia (Lamiales: Lamiaceae): a potential medicinal plant / Regeneración de plantas a partir de cultivos de callos de Vitex trifolia (Lamiales: Lamiaceae): una planta medicinal potencial

Vitex trifolia is a shrub species with popular use as a medicinal plant, for which leaves, roots and flowers have been reported to heal different distresses. The increasing exploitation of these plants has endangered its conservation, and has importantly justified the use of biotechnological tools for their propagation. Our aim was to present an efficient protocol for plant regeneration through organogenesis; and simultaneously, to analyze the genetic homogeneity of the established clonal lines by Randomly Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) markers. Plantlet regeneration was achieved in callus cultures derived from stem, leaf and petiole explants of V. trifolia on a differently supple mented Murashige & Skoog medium, and incubated at 25±2ºC under a light intensity of 61µmol/m2s from cool white fluorescent lamps and a 16h photoperiod. The rate of shoot bud regeneration was positively correlated with the concentration of hormones in the nutrient media. Shoot buds regenerated more rapidly from stem and petiole explants as compared to leaf explants on medium containing 11.10µM BAP in combination with 0.54µMNAA. Addition of 135.74-271.50µM adenine sulphate (Ads) and 0.72-1.44µM gibberellic acid (GA3) to the culture medium increased the growth of shoot buds. The highest rate of shoot bud regeneration responses was obtained in stem explants using 11.10µM BAP in combination with 0.54µM NAA, 271.50µM Ads and 1.44µM GA3. In vitro rooting of the differentiated shoots was achieved in media containing 1.23µM indole butyric acid (IBA) with 2% (w/v) sucrose. Regenerated plantlets were successfully established in soil with 86% survival under field condition. Randomly Amplified Polymorphic DNA and Inter Simple Sequence Repeat markers analyses have confirmed the genetic uniformity of the regenerated plantlets derived from the second up to fifth subcultures. This protocol may help in mass propagation and conservation of this important medicinal plant of great therapeutic potential.

Vitex trifolia es una especie arbustiva de uso popular como planta medicinal, sus hojas, raíces y flores se han reportado para la cura de diferentes aflicciones. El aumento de la explotación de estas plantas ha puesto en peligro su conservación y ha justificado el uso de herramientas biotecnológicas para su propagación. El objetivo de esta investigación fue presentar un protocolo eficiente para la regeneración de estas plantas a través de la organogénesis, y analizar la homogeneidad genética de las líneas clonales establecidas por ADN polimórfico amplificado aleatoriamente (RAPD) mediante la repetición de marcadores de inter secuencia simple (ISSR). La regeneración de plántulas se logró en cultivos de callos derivados de explantes de tallo, hoja y pecíolo de V. trifolia en un medio diferenciado Murashige & Skoog, que se incubaron a 25±2ºC bajo una intensidad de luz de 61μmol/m2s con lámparas fluorescentes blancas y un fotoperíodo de 16h. La tasa de regeneración de brotes se correlacionó positivamente con la concentración de las hormonas en el medio nutritivo. Los brotes se regeneraron más rápidamente a partir de explantes de tallo y pecíolos en comparación con explantes de hoja. La mayor tasa de regeneración de brotes se obtuvo en los explantes de tallo utilizando 11.10μM BAP en combinación con 0.54μM NAA, 271.50μM Ads y 1.44μM GA3. Este protocolo puede ayudar a la propagación masiva y conservación de esta importante planta medicinal de gran potencial terapéutico.

Diferentes concentrações de sais do meio ms e bap na multiplicação in vitro de Physalis peruviana L / Different concentrations of the ms medium and bap on multiplication in vitro of Physalis peruviana L

A Physalis peruviana L. pertence à família Solanaceae, representa um grande potencial econômico, sendo classificada como fruta fina, a exemplo do mirtilo, framboesa, cereja, amora e pitaya. Ainda tem consumo restrito por causa do alto valor agregado, em decorrência da produção limitada, do manejo da colheita, da exigência em mão-de-obra, dos cuidados no transporte e da armazenagem. Objetivou-se com este trabalho a adequação de protocolo para indução de brotações in vitro. O material vegetal utilizado foram segmentos caulinares (de aproximadamente 2 cm, contendo duas gemas) de Physalis peruviana L., oriundos da germinação das sementes in vitro. O meio de cultura básico utilizado foi o de MS nas seguintes concentrações: 0, 25, 50, 75 e 100%, combinadas com diferentes concentrações de BAP: 0, 0,5, 1,0 e 2,0 mg L-1. A adição da citocinina 6-benzilaminopurina (1,3 mg L-1) no meio MS com 50% dos sais foi eficiente para a multiplicação in vitro de Physalis peruviana L.

The Physalis peruviana L. belongs to the Solanaceae family, represents a great economic potential, and classified as fine fruit, like blueberry, raspberry, cherry, blackberry and pitaya. Although consumption has restricted because of high added value, due of limited production, the management of procurement, the requirement in manpower, transport and care of storage. The aim of this work the suitability of protocol for shoot induction in vitro. The plant material were stem segments (about 2 cm, containing two yolks) Physalis peruviana L., from of seed germination in vitro. The culture medium base used was MS in following concentrations: 0, 25, 50, 75 and 100%, combined with different concentrations of BAP: 0, 0.5, 1.0 and 2.0 mg L-1. The addition of the cytokinin 6-benzylaminopurine (1.3 mg L1 ) in MS medium with 50% of salts was efficient in vitro multiplication of Physalis peruviana L.

Screening of efficient arbuscular mycorrhizal fungi for Azadirachta indica under nursery condition: a step towards afforestation of semi-arid region of western India

To optimize nursery practices for efficient plant production procedures and to keep up to the ever growing demand of seedlings, identification of the most suitable species of arbuscular mycorrhizal fungi (AMF), specific for a given tree species, is clearly a necessary task. Sixty days old seedlings of Neem (Azadirachta indica A. Juss) raised in root trainers were inoculated with six species of AMF and a mixed inoculum (consortia) and kept in green house. Performances of the treatments on this tree species were evaluated in terms of growth parameters like plant height shoot collar diameter, biomass and phosphorous uptake capabilities. Significant and varied increase in the growth parameters and phosphorous uptake was observed for most of the AMF species against control. Consortia culture was found to be the best suited AMF treatment for A.indica, while Glomus intraradices and Glomus mosseae were the best performing single species cultures. It is the first time in the state of Gujarat that a wide variety of AMF species, isolated from the typical semi-arid region of western India, were tested for the best growth performance with one of the most important tree species for the concerned region.

Callus induction and plant regeneration of Ulex europaeus

A callus induction and plant regeneration protocol was developed from leaf and thorn explants for the plant Ulex europaeus. Explants were incubated on 2 percent sucrose half-strength Murashige and Skoog Medium (MS) with various combinations of plant growth regulators and antioxidants. The best frequency of callus and shoot formation was obtained with 2,4-dichlorophenoxyacetic acid (2,4-D) 1 mg/l x kinetin (Kin) 0.2 mg/l (DK Medium; callus induction) and zeatin (Z) 1 mg/l (DK medium; shoot induction). Both media were supplemented with ascorbic acid 200 mg/l to prevent browning and death of the explants. The regenerated shoots transferred to rooting medium (half-strength MS Medium, 2 percent sucrose) showed rapid growth and development of roots (100 percent). Rooted plantlets were successfully transferred to soil in pots containing a 3:1 mixture of soil and vermiculite.

Rapid in vitro plant regeneration from leaf explants of Launaea sarmentosa (Willd.) Sch. Bip. ex Kuntze

An efficient protocol for organogenesis through leaves has been established for Launaea sarmentosa (Willd.) Sch. Bip. ex Kuntze, a highly valuable medicinal plant. The leaf explants produced microshoots on MS basal medium when fortified with cytokinins and auxins. A combination of 6-benzylaminopurine (BAP) at 0.5mg/l and naphthaleneacetic acid (NAA) at 0.2mg/l resulted in the induction of high frequency microshoots in 30 days. The microshoots were successfully subcultured for shoot elongation and eventually for rooting on MS medium supplemented with indole-3-butyric acid (IBA) at 0.5mg/l. The regenerated plantlets were hardened under greenhouse conditions and transferred to garden, resulting in a 90% survival rate.