Search

Euryodendron excelsum H. T. Chang, a critically endangered species endemic to China, is a source of valuable material for the furniture and construction industries. However, this species has some challenges associated with rooting during in vitro propagation that have yet to be resolved. In this study, we optimized rooting and conducted a transcriptomic analysis to appreciate its molecular mechanism, thereby promoting the practical application of in vitro propagation of E. excelsum, and providing technical support for the ecological protection of this rare and endangered species. Results showed that ex vitro rooting performed the highest rooting percentage with 98.33% at 25 d. During ex vitro rooting, there was a wide fluctuation of endogenous levels of indole-3-acetic acid (IAA) and hydrogen peroxide (H2O2) at the stage of root primordia formation. Transcriptome analysis revealed multiple differentially expressed genes (DEGs) involved in AR development. DEGs involved in plant hormone signal transduction, such as genes encoding auxin-induced protein, auxin-responsive protein, and IAA-amido synthetase Gretchen Hagen3, and in response to H2O2, oxidative stress, abiotic and biotic stimuli were significantly up- or down-regulated by ex vitro treatment with 1 mM indole-3-butyric acid (IBA). Our results indicate that ex vitro rooting is an effective method to induce AR from E. excelsum plantlets during micropropagation. DEGs involved in the plant hormone signal transduction pathway played a crucial role in AR formation. H2O2, produced by environmental stimulation, might be related to AR induction as a result of the synergistic action with IBA, ultimately regulating the level of endogenous IAA.

Kendala utama dalam budidaya tanaman manggis adalah lambatnya pertumbuhan fase seedling karena minimnya akar yang terbentuk. Untuk mengatasi masalah tersebut salah satu upaya yang dapat dilakukan yaitu dengan pemberian zat pengatur tumbuh pemacu pertumbuhan akar, salah satunya menggunakan ZPT alami dari ekstrak bawang merah dan tomat. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi ekstrak bawang merah dan ekstrak tomat yang terbaik pada pertumbuhan seedling manggis. Kedua bahan ini dipilih sebagai sumber zpt karena bawang merah sering digunakan untuk pemacuan akar pada setek dan tomat sering digunakan sebagai bahan addenda pada media kultur jaringan. Penelitian ini disusun secara faktorial (3×2) menggunakan rancangan acak kelompok (RAK) dengan perlakuan ekstrak bawang merah konsentrasi 0 g L-1, 400 g L-1, dan 800 g L-1, dan ekstrak tomat konsentrasi 0 g L-1 dan 100 g L-1 yang diulang sebanyak tiga kali. Data dianalisis dengan sidik ragam dan uji lanjut BNT pada taraf 5%. Hasil penelitian menunjukkan bahwa pemberian ekstrak bawang merah konsentrasi 400 g L-1 dapat meningkatkan diameter batang, bobot segar tanaman, dan menunjukkan kecenderungan perlakuan yang terbaik pada jumlah akar sekunder seedling manggis. Pemberian ekstrak tomat 100 g L-1 dapat meningkatkan bobot segar tanaman dan terjadi interaksi antara pemberian ekstrak bawang merah dengan ekstrak tomat pada luas daun. Pada perlakuan ekstrak bawang merah konsentrasi 400 g L-1 tanpa penambahan ekstrak tomat atau perlakuan ekstrak tomat 100 g L-1 tanpa ekstrak bawang merah menghasilkan luas daun yang lebih tinggi dibandingkan dengan penggunaan kedua campuran ekstrak tersebut.

Sedum aizoon L. is a medicinal plant that contains various flavonoids and phenolic acids, and plays positive roles in lowering blood pressure, hemostasis, anti-bacterial and anti-inflammatory. However, the clinical application of Sedum aizoon L. is limited because of its low yield in natural state. Here, we aim to explore the application of adventitious root culture technology in Sedum aizoon L., further to improve the yield of Sedum aizoon L. and the production of secondary metabolites. We found that the callus of Sedum aizoon L. could be induced in MS medium containing 2.0 mg L−1 2,4-D and 0.5 mg L−1 BA. Then, the adventitious roots were obtained in Sedum aizoon L. with maximum induction rate (98.32%) when the callus were cultured in a stratified combination MS medium supplemented with 4.0 mg L−1 IBA, 1.0 mg L−1 KT, 1.0 mg·L−1 NAA and 60 mmol L−1 NO3−/NH4+ (5:1 ratio). Furthermore, the production of flavonoids in adventitious roots of S. aizoon L. (16.32±0.51 mg·g−1 DW) was obviously higher than those in the callus (3.66±0.65 mg g−1 DW). In conclusion, we determined that adventitious roots culture might be an effective alternative in improving the potential application of Sedum aizoon L..

Pyrus communis is a difficult-to-root species, and its optimal rooting depends on applying an accurate concentration of various chemicals. Since statistical modeling can be applied to estimate the approximate range of factors needed for the success of in vitro plant propagation, we tried to optimize the rooting medium using response surface methodology. Therefore, sucrose and polyvinyl alcohol were selected as independent variables in the central composite design of response surface methodology with α = 1. Based on the pre-test, it was found that the independent variables for the root formation were 2 to 3% sucrose and 0.5 to 1.5 g L−1 polyvinyl alcohol in studied cultivars. The statistical analysis results showed that the quadratic models were significant, with high R2 values > 0.9 for rooting rate response. The optimized values for independent variables in rooting of the studied cultivars included 2% sucrose, 1.5 g L−1 polyvinyl alcohol in ‘Williams’; 2.85% sucrose, 1.47 g L−1 polyvinyl alcohol in ‘Natanzi’; and 3% sucrose, 0.99 g L−1 polyvinyl alcohol in ‘Ghosi’. A separate validation experiment detected that the experimental values of the studied responses are in close agreement with predicted values in all cultivars. For the first time, the methodology was developed using a central composite design to optimize the rooting in P. communis.

Adventitious roots (ARs) are an important root type for plants and display a high phenotypic plasticity in response to different environmental stimuli. Previous studies found that dark-light transition can trigger AR formation from the hypocotyl of etiolated Arabidopsis thaliana, which was used as a model for the identification of regulators of AR biogenesis. However, the central regulatory machinery for darkness-induced hypocotyl AR (HAR) remains elusive. Here, we report that photoreceptors suppress HAR biogenesis through regulating the molecular module essential for lateral roots. We found that hypocotyls embedded in soil or in continuous darkness are able to develop HARs, wherein photoreceptors act as negative regulators. Distinct from wound-induced ARs that require WOX11 and WOX12, darkness-induced HARs are fully dependent on ARF7, ARF19, WOX5/7, and LBD16. Further studies established that PHYB interacts with IAA14, ARF7, and ARF9. The interactions stabilize IAA14 and inhibit the transcriptional activities of ARF7 and ARF19 and thus suppress biogenesis of darkness-induced HARs. This finding not only revealed the central machinery controlling HAR biogenesis but also illustrated that AR formation could be initiated by multiple pathways.

Direct plant regeneration from shoot tips and nodal explants of Wedelia calendulacea Less. was carried out in MS with different concentrations and combinations of BAP, Kn and NAA. Of the two explants nodal segments showed the best response towards the formation of multiple shoots in MS containing BAP (2.0 mg/l), Kn (1.0 mg/l) and NAA (0.5 mg/l). In this combination, the maximum number of shoots/explant obtained was 18.33 ± 0.72 from shoot tips and 26.64 ± 0.47 from nodal explants. Cent per cent root formation was obtained in MS with IBA (0.2 mg/l) within three weeks. The in vitro regenerated plantlets were successfully transplanted to soil for further growth and development. Plant Tissue Cult. & Biotech. 30(2): 277-283, 2020 (December)

The influences of indole-3-butyric acid (IBA) concentrations of 0–30 mg·g−1 on the success and speed of adventitious root development of Zamia furfuracea L.f. and Zamia integrifolia L.f. stem cuttings were determined. Root formation success for both species was greater than 95%. The IBA concentrations did not influence the speed of root development for Z. furfuracea, but the Z. integrifolia cuttings that received IBA concentration of 3 mg·g−1 generated adventitious roots more slowly than the cuttings in the control group. The ending dry weights of the stems, leaves, and roots were not influenced by IBA concentration for either species. Our results indicated that adventitious root formation on stem cuttings of these two Zamia species is successful without horticultural application of IBA. Additional IBA studies are needed on the other 300+ cycad species, especially those that are in a threatened category.

Investigation on in vitro multiple shoot regeneration in Bacopa monnieri (L.) Penn. using leaf and nodal explants was carried out on MS containing various concentrations and combinations of BAP, Kn, NAA and 2,4-D. Of the two explants, leaf showed the best response towards shoot regeneration and subsequent plant development on MS with 1.0 mg/l BAP and 0.25 mg/l Kn. In this combination, the mean number of shoots/explant was 10.6 ± 0.11 in leaf and 9.6 ± 0.29 in nodal explants. Maximum shoot length was recorded as 12.6 ± 0.21 and 11.20 ± 0.30 from leaf and nodal explants after six weeks of culture, respectively. Half strength of MS supplemented with 0.25 mg/l IBA was found to be the best medium for root formation. The in vitro regenerated plantlets were successfully transplanted in soil after acclimatization. Plant Tissue Cult. & Biotech. 30(1): 57-63, 2020 (June)

Background: Blueberry (Vaccinium corymbosum L.) is one of the most important commercial fruit tree species. The development of high-quality seedlings is a prerequisite for fruit production. Stem cutting and tissue culture methods are widely applied for propagating blueberry seedlings. Both methods require adventitious roots (ARs), indicating ARs are critical for vegetative propagation. However, the underlying factors and molecular mechanisms regulating blueberry AR formation remain relatively unknown. Results: In this study, the rooting abilities of differentially lignified cuttings from various cultivars or the same cultivars cultured differently were evaluated following an indole-3-butyric acid (IBA) treatment. Field-grown semi-lignified and tissue culture-grown cuttings formed ARs, but the latter had more pericycle and secondary xylem cells and formed ARs more easily and faster. WUSCHEL-related homeobox genes are commonly involved in vascular tissue development and early root meristem maintenance. On the basis of the available Vaccinium corymbosum genome data, 29 putative WOX genes with conserved homeodomains were identified and divided into three major clades (modern/WUS, intermediate, and ancient). These 29 WOX genes were differentially expressed in the root, shoot, leaf, flower bud, and fruit. Additionally, a qRT-PCR analysis revealed that five selected VcWOX genes were responsive to an IBA treatment during AR formation. Accordingly, VcWOX4b was functionally characterized. The overexpression of VcWOX4b in transgenic tobacco inhibited AR formation by altering vascular cell division and differentiation and the indole-3-acetic acid (IAA):cytokinin (CTK) ratio. These observations suggest that VcWOX4b regulates the IAA:CTK ratio to promote primary xylem cell differentiation, thereby inhibiting AR formation. However, an IBA treatment can induce AR formation by inhibiting VcWOX4b expression. Conclusions: Current study elucidates the rooting abilities of various cultivars and the cytological characters of influence on AR formation of blueberry cuttings, which may provide novel insights into the selection of high-quality blueberry cuttings. VcWOX4b, VcWOX8/9a, VcWOX11/12c, and VcWOX13b might regulate blueberry AR formation in an IBA-dependent manner. Ectopic expression of VcWOX4b modulated the IAA:CTK ratio to promotes primary xylem cell differentiation, but inhibit secondary xylem cell differentiation, ultimately leading to decreased AR formation.

BarkgroundAdventitious roots (ARs), which are considered as an important member of root system, have an unmatched status in plant growth and metabolism due to the degeneration of primary roots in lotus. The regulation of AR formation was previously revealed and multiple factors were recognized to be involved in this biological process. ResultsIn the present study, we sought to assess the effect of sucrose on AR formation. Based on our results, lignin metabolism, which is regulated by the sucrose signal transduction pathway, is involved in AR development. The lignification degree of the AR primordium was weaker in plants treated with 20 g/L sucrose than in control plants. However, based on the microstructural observation of the AR developmental process, 50 g/L sucrose promoted the lignification process. Lignin content, including monomer and polymer lignin, was determined in the present study. Compared with control plants, the monomer (containing 30%–45% S type and 55%–70% G type) and polymer lignin contents were lower in plants treated with 20 g/L sucrose and higher in plants treated with 50 g/L sucrose. The precursors of monomer lignin were identified in four libraries of differential developmental stages in seedlings using LC-MS/MS technique. The contents of four metabolites, including p-coumaric acid, caffeate, sinapinal aldehyde and ferulic acid for monomer lignin synthsis were lower in the GL50 library than in the GL20 library. Further analysis revealed that the gene expression of these four metabolites had no novel difference in the GL50/GL20 libraries. However, NnLAC17, a gene involved in polymer lignin synthesis, had a higher expression in the GL50 library than in the GL20 library. ConclusionsTherefore, NnLAC17 was cloned, and the overexpression of NnLAC17 was found to directly result in a decrease in AR number in transgenic Arabidopsis plants. These findings suggest that NnLAC17, which is relevant to lignin synthesis, is involved in AR formation in lotus seedlings.

El objetivo principal del experimento fue comprobar y mostrar al productor la forma correcta de siembra y manejo del cultivo de vainilla enriqueciendo el acahual con tutores de Gliricidia sepium para generar ingresos en la región asociado a la producción de vainilla, además de integrar a personas de la comunidad en las diferentes actividades del huerto. Las variables de respuesta utilizadas fueron crecimiento de brotes, distancia entre nudos, días de formación de raíces terrestres, número de hojas, longitud y ancho de las hojas encontrando que las condiciones edafoclimáticas de la Sierra Otontepec, Veracruz son perfectamente viables para el cultivo de Vanilla planifolia A, incitando a la comunidad a crear más huertos en toda la región, ya que el experimento presentó una excelente adaptación a pesar de que la época de siembra de los esquejes no fue la indicada.

Luehea divaricata, conhecida popularmente como açoita-cavalo, é uma espécie florestal nativa da Mata Atlântica muito utilizada para a recuperação de áreas degradadas. Sua madeira pode ser empregada para as mais diversas finalidades, o que contribuiu para a redução de suas populações naturais e ocasionou dificuldades na obtenção de sementes com qualidade genética, fisiológica e sanitária para uso na produção de mudas. Sendo assim, a micropropagação é uma alternativa para a produção de mudas da espécie para uso em projetos ambientais. Com isso, o presente trabalho teve como objetivo otimizar o processo de rizogênese in vitro e, para isso, foram avaliadas, inicialmente, diferentes concentrações de sais do meio nutritivo WPM. Em seguida, foram estudados os efeitos do ácido indolbutírico (AIB), adicionado ao meio em tratamento “pulse” por 15 dias, e do ácido naftalenoacético (ANA), na rizogênese, em ambos os casos em cultivo em meio WPM cuja concentração de sais foi reduzida à metade (WPM/2). Por fim, também foi analisado o efeito da combinação de volumes de vermiculita com WPM/2. Os resultados indicaram que o meio WPM/2 apresentou resultados promissores para o estabelecimento (98%) in vitro e, no que diz respeito à formação de raízes adventícias primárias, após 45 dias de cultivo in vitro observaram-se as maiores médias (40,52%), independentemente da concentração de sais do meio. O tratamento “pulse” após 30 dias de cultivo in vitro, independentemente da concentração de AIB, resultou em uma média de 25,18% de formação de raízes adventícias primárias. As combinações de 20 mL + 15 cm³, 20 mL + 30 cm³ e 30 mL + 30 cm³ de meio nutritivo e de vermiculita, respectivamente, foram as mais favoráveis para a formação de raízes adventícias laterais de segunda ordem, proporcionando médias entre 38 e 49,5% após 45 dias de cultivo in vitro. Para otimizar o processo de rizogênese de Luehea divaricata é indicado o cultivo in vitro por 45 dias em meio nutritivo WPM/2, combinado com vermiculita, prescindindo da adição de auxinas.

Relevance Biotechnological methods are generally used to speed up breeding programs and to enhance genetic diversity, so the culture of isolated microspore in vitro can be regarded as one of very suitable methods. Nontraditional and uncommon vegetable crops belonging to Brassicaceae Burnett. are becoming more popular. Methods Accessions of sarepta mustard (Brassica juncea L. Czern.) and rocket salad (Eruca sativa Mill.) were taken for the study with the aim to optimize the basic protocol for these species. Results As a result of the study the optimum cultivation conditions have been determined for the species. Sizes of buds 2.5-3.5 mm long for sarepta mustard and 7.0-7.5 long for rocket salad which were used for cultivation had been experimentally defined. It was also shown that the cold pretreatment had improved the embryo yield. The nutritional NLN-13 medium with pH 6.1 and pretreatment at 32°C during a cultivation day had been shown to be more favourable for all accessions. All conditions that had been used were suitable for embryo formation. First divisions had been seen after 4 days of cultivation, while the embryos at primary cotyledonary stage only appeared after 2 weeks of cultivation. The embryo yield per 5 buds reached 25-30 and 5-7 in the sarepta mustard and the rocket salad, respectively. It is worth noticing that the root formation and plant adaptation had passed better and faster in sarepta mustard than in rocket salad. Thus, whole process of homozygous line developing can be completed for 4-5 months, making the breeding program 3 times shorter.

MicroRNAs (miRNAs) have been shown to play key roles in the regulation of plant growth and development by modifying the expression of their target genes. However, the influence of miRNAs on root formation and development in woody plants, such as Taxus chinensis, remains largely unknown. In the current study, we explored the phytohormone-response and nutrition-response miRNA expression profiles during T. chinensis rooting by quantitative real-time PCR (qPCR). We identified six phytohormone-response miRNAs, namely, miR164a, miR165, miR167a, miR171b, miR319, and miR391, and eight nutrition-response miRNAs, namely, miR169b, miR395a, miR399c, miR408, miR826, miR827, miR857, and miR2111a, that were differentially expressed at different rooting phases of T. chinensis. Using northern blot analysis of the putative target genes of these miRNAs, we detected the relative gene expression changes of the target genes. Taken together, our results suggest that miRNAs are involved in root formation of T. chinensis and that miRNAs may play important regulatory roles in primary root, crown root, and root hair formation by targeting phytohormone and/or nutrition response genes in T. chinensis. For the first time, these results expand our understanding of the molecular mechanisms of plant root formation and development in a conifer species.

SUMMARY: Sequoia sempervirens is a fast-growing, long-lived tree with pest-resistant wood. The objective of this study was to quantify the adventitious rooting ability of sequoia clones in two environments as well as determining rooting behavior during the evaluation period. Mini-cuttings of five clones grown in a clonal mini-garden were planted for rooting in two different environments: a mini-tunnel and an intermittently fogging greenhouse. Weekly assessments (from 30 to 93 days) of the variables were performed: survival, rooted mini-cuttings and number of roots emitted. Rooting speed varied in relation to the clones, occurring mainly between 50 and 60 days after planting, with the appearance of new roots between 70 and 80 days. The cultivation environment promoted distinct responses in the rooting process, being earlier in the greenhouse environment, although with a higher index in the mini-tunnel at the end of the evaluation. The process of differentiation of mini-cuttings occurs initially with the formation of calluses, around 15 days, followed by rooting (between 30 and 60 days) and the subsequent appearance of new roots. The rooting of sequoia mini-cuttings can be done in a mini-tunnel, with good indexes for all clones. It is recommended to keep mini-cuttings in this environment for 90 days for good root formation.

The article presents data on the complex influence study of new microbial preparations Diazophyte, Phosphoenterin, Biopolicide, Aurill and Azotobacterin on biometric indicators of growth and development of grapes rootstock at separate rhizogenesis stages. Standard cuttings of the Berlandieri x Riparia Kober 5 BB rootstock grape variety were used as objects of the four-year study. For the first time, the optimal breeding range of the studied microbial complexes (MPC-1 and MPC-2 in dilution 1:10) was determined; with it, stable efficiency of root formation stimulation of subpar grape variety Berlandieri x Riparia Kober 5BB cuttings was observed. In turn, this is the basis for future studies aimed at finding the optimal concentration in this range. By its effectiveness, the use of these microbial complexes approaches the action of the traditional chemical stimulant Heteroauxin at a concentration of 0.02%.

MADS-box genes are important transcription factors affecting overall development, but their role in sweet potato [Ipomoea batatas (L.) Lam.] has not been fully studied. This study isolated six novel MADS-box genes (IbSOC1, IbFUL1, IbAGL6, IbSVP1, IbSVP2, and IbSVP3) from sweet potato [Ipomoea batatas (L.) Lam. cv. Annouimo] during the early root differentiation stage using the de novo transcriptome assembly sequencing method. At the early root differentiation (between 0 and 3 days after transplanting), the IbSOC1, IbFUL1, and IbSVP2 genes decreased rapidly, whereas the IbSVP3 gene decreased gradually. In the early stages of root formation (0-30 days), the levels of IbSVP1 and IbSVP3 expression were steady, but the levels of IbSOC1 expression decreased gradually. The expression of six novel genes was also conducted in the tuberous root formation stage (30-90 days), and the IbSVP3 gene increased significantly according to the formation of the tuberous root. Six novel MADS-box genes that were believed to influence the entire root formation of sweet potato were isolated from the sweet potato. This study provides a genetic basis for further research on sweet potato root formation and development.

The aim of the study was to find an efficient culture medium for regeneration of Physalis species in vitro to provide their further propagation ex vitro and obtain fructiferous plants from the regenerants. Physalis peruviana L., P. ixocarpa Broth. (cv. Likhtaryk), and P. pubescens L. (cv. Zarynka) were taken as plant material for the research. Plant introduction into culture and regenerant production were carried out in vitro; the rooting of mature plants and obtaining plants with ripe fruits took place in a greenhouse and in open ground (ex vitro). To obtain regenerants, we used Murashige and Skoog (MC30) medium supplemented with the growth stimulant zeatin (Zea) at a concentration of 0.5–3 mg/l. The growth stimulant 6-benzylaminopurine (BAP) was used to elongate the regenerant stalks, and the growth stimulator α-naphthylacetic acid (NAA) was used to initiate root formation. Plant regeneration frequency and the number of regenerants per explant served as indicators of the efficiency of various zeatin concentrations on the physalis regenerative capacity. The most effective media for the shoot regeneration from cotyledonous leaf explants were MC30 + 1 mg/l Zea and MC30 + 2 mg/l Zea. Regeneration frequency on these media was 46.15 % and 53.84 % for P. ixocarpa (cv. Likhtaryk), 38.46 % and 45 % for P. peruviana, and 27 % and 34 % for P. pubescens (cv. Zarynka) respectively. The emerged regenerants were separated from explants and transferred to MC30 medium supplemented with 1 mg/l of BAP + 0.1 mg/l of NAA for stalk growth and rooting. After a month of cultivation, juvenile plants were obtained. They were transferred to a greenhouse for adaptation, and later to open ground at the experimental plot. Three months after the regenerant emergence, we obtained fertile plants, which bloomed and bore fruit. The regenerants for domestic varieties of P. ixocarpa (cv. Likhtaryk) and P. pubescens (cv. Zarynka) were obtained for the first time. We established a direct relationship between the concentration of zeatin and both the frequency of plant regeneration and the number of regenerants per explant.

One of the biggest challenges in clonal propagation of grapevine (Vitis vinifera) is difficulty of rooting. Adventitious root initiation and development are the critical steps in the cutting and layering process of grapevine, but the molecular mechanism of these processes remains unclear. Previous reports have found that microRNA (miRNA)-encoded peptides (miPEPs) can regulate plant root development by increasing the transcription of their corresponding primary miRNA. Here, we report the role of a miPEP in increasing adventitious root formation in grapevine. In this study, we performed a global analysis of miPEPs in grapevine and characterized the function of vvi-miPEP171d1, a functional, small peptide encoded by primary-miR171d. There were three small open reading frames in the 500-bp upstream sequence of pre-miR171d. One of them encoded a small peptide, vvi-miPEP171d1, which could increase the transcription of vvi-MIR171d. Exogenous application of vvi-miPEP171d1 to grape tissue culture plantlets promoted adventitious root development by activating the expression of vvi-MIR171d. Interestingly, neither exogenous application of the vvi-miPEP171d1 peptide nor overexpression of the vvi-miPEP171d1 coding sequence resulted in phenotypic changes in Arabidopsis (Arabidopsis thaliana). Similarly, application of synthetic ath-miPEP171c, the small peptide encoded by the Arabidopsis ortholog of vvi-MIR171d, inhibited the growth of primary roots and induced the early initiation of lateral and adventitious roots in Arabidopsis, while it had no effect on grape root development. Our findings reveal that miPEP171d1 regulates root development by promoting vvi-MIR171d expression in a species-specific manner, further enriching the theoretical research into miPEPs.

Ganoderma is a major pathogen in oil palm crops. Some efforts related to control the growth of Ganoderma have been conducted but still have not found an effective method. This study aims to develop an organic fungicide that has been tested in vitro , which effective in controlling the growth of Ganoderma . The optimization carried out includes the determination of the dose and time interval for application in 13-year-old mature oil palm. This organic fungicide application was the continuation of application during the previous year especially for the two best treatment which is application organic fungicide every week (1w) and every two weeks (2w). In this study, the treatments tested were three levels dose of organic fungicide (0, 1x and 2x) and two types of frequency application, i.e. every week (1w) and every other week (2w). The results showed that the best application of organic fungicides was every week application with twice doses (1w.2x), based on the parameters of the inhibition of Ganoderma’s fruiting body formation, primary and secondary root formation, the opening of spear leaves, and harvesting parameters. The application of organic fungicide able to recover the oil palm infected Ganoderma sp., with increasing the fresh fruit bunch and its weight around 70% and 78%, respectively .

Background: Lotus is an aquatic horticultural crop, and widely cultivated in most regions of China. Lotus is often used as a kind of an important off-season vegetable with various nutrients. Principle root of lotus is degenerated, and the role of adventitious roots (ARs) is Irreplaceable for plant growth. We found that no ARs could be formed under darkness condition, and high light significantly promote the development of root primordium. Therefore, four libraries with three light intensities were constructed to monitor metabolism changes, especially in IAA and sugar metabolism. Results: We found that ARs formation was significantly affected by light, high light intensity accelerated ARs development. The change of metabolism during ARs formation under different light intensity was evaluated according to gene expression profiling by high-throughput tag-sequencing. It was shown that more than 2.2× 10 4 genes was obtained in each library, and the expression level of most genes were distributed between 1e-01 and 1e+03 (FPKF value). Among these identified genes, 1739, 1683 and 1462 genes were up-regulated, and 1533, 995 and 834 genes were down-regulated in D/CK, E/CK and F/CK libraries respectively. In addition, we also found that 1454 and 478 genes changed expression in D/CK and F/CK libraries when compared D/CK with F/CK libraries. In F/D libraries, the transcriptional level of most differentially expressed genes was between -5~5 fold, and twenty differentially expressed genes were involved in signal transduction pathway. Twenty-eight genes related with IAA response and thirty-five genes involved in sugar metabolism were found to change expression. It was elucidated that IAA content was enhanced after seed germinated, even in darkness condition, which was responsible for ARs formation. Conclusion: The process of ARs formation was very complex, and regulated by multiple factors. The ARs formation was regulated by IAA, even in the dark, induction and developmental process could also be completed. In addition, the genes (36 genes) changed expression level in carbohydrate metabolism showed the third number, so sucrose metabolism was involved in the ARs development (expressed stage) according to genes expression and content change characteristic.

Catasetum macrocarpum is an epiphytic orchid that has been subjected to strong environmental pressure in the state of Tocantins. This investigation aimed at studying the germination, growth and morpho-anatomical development of C. macrocarpum under in vitro conditions. The effects of three culture media on the in vitro germination and on the multiplication and growth of 90-day-old seedlings were studied: Murashige & Skoog (full- and half-strength), Knudson C, and Vacin & Went. The effects of different concentrations of benzyladenine (BA) and naphthaleneacetic acid (NAA) on the multiplication and growth of 120-day-old plants were evaluated. Anatomical studies were conducted on protocorms at different developmental stages. Acclimatization was also carried out. Knudson C was the best medium for seed germination whereas Vacin & Went promoted the greatest protocorm development. Half-strength Murashige & Skoog was the most effective medium for seedling multiplication and growth. The results revealed that 1 mg L-1 BA was the best treatment for shoot proliferation and leaf production. NAA at 0.5 mg L-1 strongly favored root formation. The anatomical study revealed that the early stages of C. macrocarpum development do not always coincide with the morphological phases described. The acclimatization of C. macrocarpum plants provided successful results regarding plant survival.

In sweetpotato (Ipomoea batatas), the successful emergence and development of lateral roots (LRs), the main determinant of root system architecture (RSA), determines the competency of adventitious roots (ARs) to undergo storage root formation. The present study investigated the effect of three levels of root-knot nematode (RKN) inoculum of race 3 of Meloidogyne incognita on LR length, number, area, and volume in ‘Beauregard’, ‘Evangeline’, and ‘Bayou Belle’, sweetpotato cultivars which are highly susceptible, moderately resistant, and highly resistant, respectively, to M. incognita. The three RKN levels were control (untreated), medium (500 eggs/pot), and high (5000 eggs/pot). In general, the number of galls after 20 days for each cultivar was consistent across RKN levels and two planting dates (PDs). ‘Beauregard’ inoculated with medium and high RKN levels showed 2.9 and 18.9 galls on each AR, respectively. ‘Evangeline’ had 0.5 and 3.4 galls at medium and high RKN levels, respectively. By contrast, ‘Bayou Belle’ showed only 0.9 galls at the high inoculum level. There was a significant PD × cultivar effect and cultivar × RKN level effect for all root attributes. LR attributes varied within and among resistant and susceptible cultivars with a general trend for increase in all root growth attributes in response to RKN infection in the first (PD1) and second PD (PD2). ‘Evangeline’ showed relatively consistent within-cultivar increase across PD1 (medium and high RKN levels) and PD2 (medium RKN level only). LR length, number, area, and volume within ‘Evangeline’ plants subjected to high RKN increased 122%, 126%, 154%, and 136%, respectively, relative to the untreated control plants in PD1. ‘Evangeline’ (PD1 and PD2) and ‘Bayou Belle’ (PD1 only) showed significant increase in all root attributes relative to the susceptible ‘Beauregard’ at medium or high RKN levels. In PD1, LR length, number, area, and volume in ‘Evangeline’ plants subjected to high RKN increased 165%, 167%, 176%, and 190%, respectively, relative to ‘Beauregard’ plants at the same RKN level. These findings are consistent with some data in other systems wherein nematode infection is associated with cultivar-specific root compensatory growth and demonstrate how genotype and environment interact to modify root development responses. These data can be used to further understand the role of cultivar-specific responses to nematode infection and can lead to the consideration of root traits in selection strategies.

The article presents data on the use of growth stimulators on the rooting of hardwood cuttings. Treatment drug “Samorod” increases the rooting of hardwood cuttings of Philadelphus coronarius and on Tamarix of 69,8 and 73,1%, and increases the length by 57,1-58,8 percent, compared to the control variant. The use of growth stimulator “Heteroauksin” promotes the formation of roots of hardwood cuttings by 34,4-68,1%, and an increase in length by 43,8-69,5%, relative to the control option. Treatment with growth regulators “Heteroauxin” and “ Samorod “ enhances the processes of root formation of hardwood cuttings of Philadelphia coronarius and Tamarix, contributing to an increase in the number and length of roots formed.

Large stem cuttings were removed from Cycas micronesica K.D. Hill trees and used for asexual propagation to more fully understand resource factors that influence adventitious root formation success. Healthy source trees had received insecticide protection from ubiquitous Aulacaspsis yasumatsui Takagi infestations and unhealthy source trees had suffered from chronic A. yasumatsui infestations. Nonstructural carbohydrates were quantified from stem tissues at the base of each 1-m cutting, and induction of adventitious roots was attempted using field soil as the medium. Carbohydrate concentrations were increased in healthy, protected tree cuttings above those in unhealthy, infested tree cuttings. The relative increase was greatest in the hexoses, intermediate in sucrose, and least in starch. The total nonstructural carbohydrate concentration in cuttings of infested trees was 54% of that of protected trees, and the sugar/starch quotient of infested trees exceeded that of protected trees. Asexual propagation success was 30% for the unhealthy tree cuttings and 100% for the healthy tree cuttings. These manipulative experiments confirm that chronic A. yasumatsui herbivory of C. micronesica trees reduces stem carbohydrates and decreases asexual propagation success. The results indicate that the use of large cuttings from unhealthy C. micronesica trees to rescue tree populations from construction sites is not a wise conservation decision in habitats where A. yasumatsui herbivory has been uncontrolled. Protocols for future rescue operations designed to transplant C. micronesica trees from construction sites may be improved by this new knowledge.

Impact of ANA and sucrose concentrations on the in vitro rooting of Butia odorata (Barb. Rodr.) Noblick. The objective of this study was to evaluate the culture medium seeking the development and root formation of pindo palm seedlings for acclimatization. The MS medium were used at a concentration of 70% ammonium nitrate and potassium nitrate, and 0.8% of agar. In the fi rst experiment, concentrations of naphthaleneacetic acid (ANA) added to the medium were tested. In the second, the rooting and growth of the seedlings were evaluated after varying the sucrose concentration (15, 30 and 45 g.L-1) in medium with 0.6 mg.L-1 of ANA. A third experiment was carried out to adjust the ANA concentration, based on the results of the fi rst two tests. The rooting of Butia odorata seedlings were optimized in vitro in medium with 0.3 to 0.9 mg.L-1 of ANA, combined with concentrations of sucrose between 30 and 45 g.L-1 El objetivo del estudio fue evaluar medios de cultivo buscando el desarrollo y formación de raíces en plantas de butiacero para la fase de aclimatización. Se utilizó el medio MS con 70% de la concentración del nitrato de amonio y nitrato de potasio y 0,8% de agar. En el primer experimento se testaron concentraciones del ácido naftalenacético (ANA) en el medio. En el segundo, se evaluó el enraizamiento y el crecimiento de las plantas respecto a la variación de la concentración de sacarosa (15, 30 y 45 g.L-1) en medio añadido con 0,6 mg.L-1 del ANA. El tercer experimento se realizó con el fi n de ajustar la concentración del ANA a partir de los resultados de los dos primeros estudios. Plantas de Butia odorata tienen su enraizamiento in vitro optimizado en medio con 0,3 hasta 0,9 mg.L-1 ANA combinado a concentraciones de sacarosa entre 30 y 45 g.L-1.

The formation of adventitious roots (ARs) is an important process for lotus (Nelumbo nucifera), which does not have a well-formed main root. In lotus, the removal of leaves above the waterline significantly promoted AR formation, while the removal of leaves below the waterline inhibited AR formation. Proteins were identified using isobaric tags for relative and absolute quantization technique. The number of proteins decreased with increasing sequencing coverage, and most of the identified proteins had fewer than 10 peptides. In the A1/A0 and A2/A1 stages, 661 and 154 proteins showed increased abundance, respectively, and 498 and 111 proteins showed decreased abundance, respectively. In the B1/B0 and B2/B1 stages, 498 and 436 proteins showed increased abundance, respectively, and 358 and 348 proteins showed decreased abundance, respectively. Among the proteins showing large differences in abundance, 17 were identified as being related to AR formation. Proteins involved in the glycolytic pathway and the citrate cycle showed differences in abundance between the two types of leaf removal. The transcriptional levels of nine genes encoding relevant proteins were assessed by quantitative polymerase chain reaction. The results of this study illustrate the changes in metabolism after different types of leaf removal during AR formation in lotus.

Medicinal plants are important objects for botany, systematics and plant geography research, as well as physiology, pharmacology, and biotechnology. Medicinal plants from the Lamiaceae family are being intensively studied for medical and pharmacological reasons. This family also includes the medicinal herbaceous plant oregano (Origanum vulgare L.), known from ancient times for its antimicrobial and antifungal properties, the ability to strengthen the human immune system, and to improve the general state of an organism. At present, the study of its antimicrobial, antifungal, insecticidal, anticoagulant, antitumor, therapeutic and many other properties is being actively continued. Due to the relevance of the development of the principles of O. vulgare micropropagation in vitro and the undeveloped conditions and methods of its cultivation, the aim of this work was to optimize microclonation in vitro of oregano via the activation of auxiliary buds. The research tasks were to test the ability of auxiliary buds to be activated depending on the localization on the donor shoot internodes and to intensify the root formation of cuttings through medium content optimization. The influence of the location of the auxiliary buds on donor shoots on their activation in vitro was studied on such indicators as the length of newly formed shoots, the number of nodules per one newly formed shoot, and the number of newly formed shoots per one bud. In plant microclonal propagation, the stage of root formation is very important for further adaptation in soil. Practical experience has shown that for the effective adaptation of oregano in soil, the length of the root system for cuttings should be 1.5–2.0 cm, the degree of root system development – 4–5 points under shoot length of 3–5 cm. The study of peculiarities of oregano microclonal propagation via activation of auxiliary buds has allowed us to optimize the stage of explant selection for cutting and the formation of cuttings’ roots. It has been established that for optimal length, the number of nodules of the newly formed shoots and the number of newly formed shoots, the first internode, located on the top of a parent shoot, as well as the third to fifth ones are more suitable. For rooting oregano cuttings, the optimal medium on the ratio of length and density of root system and on shoot length is the nutrient one containing half of the macro-, microsalts and vitamins on Murashige-Skoog, 20 g/l sucrose and 0.75 mg/l kinetin.

The mycorrhizal-like fungus Piriformospora indica has demonstrated potential to enhance adventitious root formation (ARF) and increase root weight when applied to the propagation substrate of unrooted cuttings (URCs). Experiments were conducted to determine the effect of P. indica on ARF of six floriculture species: cape daisy (Osteospermum ×hybrida ‘Side Show White’), crossandra (Crossandra infundibuliformis ‘Orange Marmalade’), dahlia (Dahlia ×hybrida ‘Dahlietta Margaret’), lantana (Lantana camara ‘Lucky Yellow’), poinsettia (Euphorbia pulcherrima ‘Champion Fire’, ‘Premium White’, and ‘Supreme Bright Red’), and scaevola (Scaevola aemula ‘Fan Dancer’). The treatments consisted of a peat-based growing medium that contained 5%, 10%, 20%, or 30% perlite colonized with P. indica (volume of colonized perlite/volume of growing medium). Inoculation with 10% to 20% colonized perlite significantly increased the root fresh weight for one cultivar, Supreme Bright Red poinsettia, whereas the 20% colonized perlite treatment resulted in a decrease in root fresh weight of scaevola and cape daisy. Rooting percentage of ‘Champion Fire’ poinsettia and dahlia showed a benefit at specific P. indica treatments, whereas cape daisy displayed a decrease in rooting percentage. Conventional rooting hormone treatment showed beneficial responses for dahlia, and ‘Champion Fire’ poinsettia rooting percentage and a negative response on lantana root fresh weight. This project demonstrates a novel method for delivering a root endophyte to URCs for the purpose of increasing ARF, and the results suggest the potential for P. indica usage for ARF enhancement. However, the results were not consistently beneficial across the eight cultivars tested, so growers would need to conduct in-house trials to identify the best treatments across a range of crop species and cultivars.

Miscanthus can help achieve renewable energy and GHG mitigation targets but establishment costs of rhizome systems are high. The objective of this study was to examine if stem material could be used to establish field miscanthus crops. Field trials were established to investigate the optimum sowing time for miscanthus stem segments. In two planting seasons, stem segments of miscanthus were cut in September, October or March and either planted immediately or placed in cold storage. These stem segments of 1.8 m length were planted horizontally underneath the ground at a depth of 100 mm. In a separate set of experiments conducted under control conditions, stem segments were harvested each month and placed in a growth cabinet for sixty days. Basal stem pieces of 650 mm length were harvested from a rhizome crop established in 1994 and 2010 and these stems were either stripped of leaves or left with leaves attached to the stem. The growth cabinet experiments showed that the age of the mother crop or leaf removal had no effect on shoot or root formation but that both root and shoot formation were at a maximum in September and decreased thereafter. Establishment rates, average height, stem numbers and biomass yield in the field trials was maximised through a September harvest and planting date in both trial years (P

An efficient protocol for in vitro plant regeneration from cotyledonary nodal segment explants of Prosopis cineraria (L.) Druce., a multipurpose leguminous tree, was established. Nodal explants were excised from 5-day-old seedlings and cultured on Murashige and Skoog (MS) medium fortified with different concentrations of BAP (0.44–2.22 µmol/l) alone for shoot bud regeneration. Highest percent of shoot bud regeneration (87.66%) was noticed on MS medium supplemented with 2.22 µmol/l BAP. The nodal segments derived from seedlings were placed on MS medium with different concentrations of BAP (0.44–2.22 µmol/l) in combination with 0.46 µmol/l for shoot bud multiplication. The highest percent of shoot bud multiplication (93.50%) with 3.5 shoots/explant was recorded on MS medium containing 2.22 µmol/l BAP and 0.46 µmol/l KIN combination. The number of multiple shoots was further increased to 12.0 shoots/culture when the combination of 2.22 µmol/l BAP, 0.46 µmol/l KIN and 0.59 µmol/l AgNO3 was used. For rooting, the elongated shoots (>2 cm) were cultured on MS medium augmented with various concentrations of NAA (0.53–2.68 µmol/l) along with 0.46 µmol/l KIN and 0.59 µmol/l AgNO3. Among the combinations tested, the highest percent of root formation (87.66%) with 4 roots/shoot was observed in the medium containing 0.53 µmol/l NAA, 0.46 µmol/l KIN and 0.59 µmol/l AgNO3 combination. Rooted plantlets were successfully transferred into plastic cups and acclimatized under greenhouse conditions. Subsequently, they were established in the field and grew normally.

La Caña Agria (Cheilocostus speciosus. J. Koenig) es una planta floral decorativa, usada en la producción de artesanías derivadas de la Caña Flecha (Gynerium sagittatum. Aubl.), en los municipios de San Andrés de Sotavento y Tuchín, del departamento de Córdoba en Colombia, por sus propiedades para el blanqueamiento de fibras de Caña Flecha. Debido a la escasa presencia de plantas de Caña Agria en los resguardos indígenas de Túchin y San Andrés de Sotavento, se consideró necesario investigar nuevos métodos de propagación con el objetivo de conformar bancos de semillas que permitan aumentar la disponibilidad de material vegetal. Para ello, se seleccionaron esquejes de tallo de aproximadamente 11 cm de longitud, y se evaluó el efecto de tres concentraciones (0,0; 500 y 1000 mg·L-1 de ANA), sobre el enraizamiento. Los esquejes se colocaron en cada concentración por 10 días, y transcurrido el tiempo, se pasaron a bandejas con tierra en condiciones semicontroladas de temperatura y humedad. 30 días posteriores al trasplante, se establecieron los porcentajes de sobrevivencia y de enraizamiento de los esquejes. Como resultado, se encontró que los tratamientos con ANA aumentan la formación de raíces. El mejor tratamiento para enraizar esquejes fue el de 500 mg·L-1, con un porcentaje de enraizamiento del 96% a los 10 días después de la inducción. Por otra parte, Los tratamientos correspondientes a 0,0 mg·L-1 y 1000 mg·L-1 generaron porcentajes de enraizamiento del 24% y 70% respectivamente. El mayor número de raíces por planta con promedio de 8,76, se obtuvo en la solución 500 mg·L-1 de ANA. The Caña Agria (Cheilocostus speciosus, J. Koenig) is a decorative floral plant, used in the production of handicrafts derived from the Cane Flecha (Gynerium sagittatum, Aubl.), in the municipalities of San Andrés de Sotavento and Túchin, department of Córdoba in Colombia, for its properties for the fiber whitening of Caña Flecha. Due to the scarce presence of Caña Agria plants in the indigenous reserves of Túchin and San Andrés de Sotavento, it was considered necessary to investigate new methods of propagation with the objective of forming seed banks that allow to increase the availability of plant material. To do this, stem cuttings of approximately 11 cm in length were selected, and the effect of three concentrations (0.0, 500 and 1000 mg • L-1 of ANA) was evaluated on the rooting. The cuttings were placed in each concentration for 10 days, and after the time, they were transferred to trays with soil under semicontrolled conditions of temperature and humidity. 30 days after the transplant, the percentage of survival and rooting of the cuttings were established. As a result, it was found that ANA treatments increase root formation. The best treatment to root cuttings was the 500 mg • L-1, with a percentage of rooting of 96% at 10 days after induction. On the other hand, the treatments corresponding to 0.0 mg • L-1 and 1000 mg • L-1 generated percentages of rooting of 24% and 70% respectively. The highest number of roots per plant with an average of 8.76 was obtained in the 500 mg • L-1 ANA solution.

Orchids are the most adorable in flowering plants, cultivated as the cut flower and potted plants throughout the world at different occasions. For their commercial exploitation and conservation of endangered species, micropropagation has been extensively practiced, which may be affected by several factors at each step. In vitro rooting is the most important stage that may ultimately be responsible for successful transplantation of the plantlets. Auxins play a vital role for in vitro rooting. In present study NAA and IBA treatments to in vitro developed microshoots produced multiple responses. Findings show that NAA concentrations alone were better and vigorous than IBA alone in terms of number, length and root thickness. Increasing the NAA concentration from 0.1 to 3.0 mg l-1 proved progressive. The highest significant value in root development was obtained with NAA at 3.0 mg l-1. In case of IBA alone, the root number was increased by increasing its concentration up to 1.0 mg l-1 but, root number decreased when the concentration of IBA was increased to 3. 0 mg l-1. However, the combined effect of both the PGRs over root formation indicated a considerable decline in root formation as well as callus formation at microshoot bases.

INFLUENCIA DA AUXINA E TIPOS DE SUBSTRATOS NA FORMACAO DE RAIZES EM ESTACAS DE NIM INDIANO (Azadirachta indica A. Juss) Azadirachta indica e uma planta lenhosa perene da familia Meliaceae, nativa do subcontinente indiano e com distribuicao nas regioes tropicais e subtropicais do mundo. Para a multiplicacao eficiente e a conservacao dos recursos geneticos do nim indiano, avaliou-se os efeitos de diferenes concentracoes de auxina e de diferentes meios de enraizamento (substratos) na formacao de raizes adventicias (ARF) em estacas de madeira semi-dura de Azadirachta indica . Foram avaliados tres meios de enraizamento diferentes (areia, vermiculita e solo), tres tipos de auxina (IBA, IAA e NAA) e 6 concentracoes (100, 250, 500, 750, 1000 e 1500 mg L-1), em delineamento completo de blocos causalizados (DBC). Foram observados efeitos significativos do tipo de auxina, da concentracao e dos meios de enraizamento na formacao de raizes adventicias de estacas semi-duras de nim indiano. As estacas foram avaliadas quanto ao percentual de enraizamento, numero de brotos, numero de raizes, comprimento da raiz e numero de folhas. Os dados revelaram que houve efeito significativo (p < 0,05) de auxina-vermiculita em todas as variaveis analisadas. Os dados mostraram que foi obtido um maximo de 65% de enraizamento com medias de 3.00 brotos, 32.38 raizes com comprimento medio de 5.77 cm e 4.92 numeros de folhas, quando as estacas foram tratadas com 500 ppm de IBA. A determinacao de protocolos de enraizamento adequados e o uso de estacas de madeira semi-duras foram comprovados como as melhores opcoes para a multiplicacao de A. indica. As plântulas enraizadas foram aclimatadas em estufas de polietileno de baixa densidade e em telados com sombreamento agricola. Estas plantas mostraram boa taxa de sobrevivencia de 80% em condicoes de campo. Palavras-chave : estacas de madeira semi-dura, hormonios vegetais, substratos, nim indiano. ABSTRACT: Azadirachta indica is an evergreen woody plant of Meliaceae family, native to Indian subcontinent and distributed in the tropical and subtropical regions of the world. For efficient multiplication and conservation of the genetic resources of neem, the effect auxin, their different concentration in different rooting media on adventitious root formation (ARF) in semi - hard wood cuttings of Azadirachta indica was studied. Three different rooting media (sand, vermiculite and soil) were used and the experiment was established using three types of auxin (IBA, IAA and NAA) and 6 concentration (100, 250, 500, 750, 1000 and 1500 mg L-1), in a complete randomized block design (CRBD). Significant effects of auxin, their concentration and rooting media on adventitious root formation of neem semi hard wood cuttings were observed. Semi hard wood cuttings were assessed for rooting percentage, number of sprouts, number of roots, root length and number of leaves. Data revealed that there was significant effect (p < 0.05) of auxin - vermiculite on rooting percentage, number of sprouts, number of root, length of root and number of leaves. The data showed that a maximum of 65% rooting with 3.00 numbers of sprout, 32.38 number of roots with 5.77 cm root length and 4.92 numbers of leaves was obtained, when these cuttings were treated with 500 ppm IBA. The determination of proper rooting protocols and the use of semi hard wood cuttings were proved important for multiplication of A. indica. The rooted plantlets were successfully hardened and acclimatized in poly house and agro shade house. These plants showed a good survival rate of 80% under field conditions. Keywords : semi - hard wood cutting, vegetable hormone, rooting media. DOI: http://dx.doi.org/10.5935/2318-7670.v05n04a10

A study conducted with the aim of developing a protocol for callus induction and plantlet regeneration in vitro from leaf segments of three accessions of African rice (O. glaberrimaSteud.) indigenous to Ghana. Leaf segments of the accessions namely, Guame, N/4 and SARI 1 were assessed for callus induction and plantlet regeneration ability on different concentrations of plant growth regulators, incorporated into Murashige and Skoog, (1962) (MS) basal medium. Frequency of callus induction which was achieved on MS medium supplemented with (0-10) mg/l 2,4-D differed significantly (p≤0.05) among the accessions, as well as among the levels of 2,4-dichlorophenoxyacetic acid (2,4-D) tested. Highest callus induction frequency was exhibited at a concentration of 6 mg/l 2,4-D for all three accessions.Sub-culturing of callus on regeneration medium, which consisted of MS supplemented with (1:0-5) mg/l NAA:BAP resulted in no plantlet regeneration in all tested accessions. Instead, prolific root formation was observed.

Past endosymbiotic events allowed photosynthetic organisms to flourish and evolve in terrestrial areas. The precursor of chloroplasts was an ancient photosynthetic cyanobacterium. Presently, cyanobacteria are still capable of establishing successful symbioses in a wide range of hosts. One particular host plant among the gymnosperms is cycads (Order Cycadales) in which a special type of root system, referred to as coralloid roots, develops to house symbiotic cyanobacteria. A number of studies have explained coralloid root formation and cyanobiont invasion but the questions on mechanisms of this host-microbe association remains vague. Most researches focus on diversity of symbionts in coralloid roots but equally important is to explore the underlying mechanisms of cycads-Nostoc symbiosis as well. Besides providing an overview of relevant areas presently known about this association and citing putative genes involved in cycad-cyanobacteria symbioses, this paper aims to identify the limitations that hamper attempts to get to the root of the matter and suggests future research directions that may prove useful.

Grevillea (Proteaceae) is one of the woody Australian native species that have a high commercial value in the floriculture market. Grevillea spp. varies greatly in their ease of propagation from cuttings, and some Grevillea cultivars are considered to be difficult-to- root. Efforts to improve propagation success are essential if this species is to be developed for commercial production. The objectives of this study were to observe the response of Grevillea cuttings to exogenous auxin, and to determine whether or not rooting differences between the difficult and easy-to-root cultivars could be explained by differences in endogenous auxin levels, auxin uptake, transport and/or metabolism.GC-MS analysis was used to measure the levels of auxin in the plants. The level of auxin in the endogenous pool was measured by adding 13C-labelled IAA (I3C6-IAA) and 13C1- labelled IBA (13C1-IBA) as internal standards for quantitative mass-spectral analysis. The capacity for auxin transport in cuttings of the two Grevillea cultivars was estimated by applying radio labelled auxin with high specific activity (3H-IBA, Bioscientific Pty) to the cuttings. The distribution of radioactivity was determined in the cutting base, leaves and the rest of the stem harvested at various time points. Confirmation of the quantity of radiolabel maintained as [3H]-IBA during this period was monitored by HPLC-radio detection.Apical auxin application to the difficult-to-root cultivar "Coastal Dawn" resulted in a higher or comparable percentage of rooting compared to basal application in autumn and might potentially reduce the amount of auxin required to induce rooting.Rooting differences between the difficult and easy-to-root Grevillea cultivars are unlikely to be related to their endogenous auxin levels or their ability to uptake applied auxin. This conclusion was based on the findings that (1) there were no significant differences in the endogenous IAA and IBA levels between the easy and difficult-to-root cultivars and (2) both cultivars demonstrated an increase in endogenous IAA and IBA levels following IBA application; the increase in the difficult-to-root "Coastal Dawn" being more pronounced than in the easy-to-root "Royal Mantle".A different distribution pattern of the applied [3H]-IBA was noted between "Coastal Dawn" and "Royal Mantle". The applied IBA in "Coastal Dawn" moved to the leaf rather than the stem base, whereas in "Royal Mantle" it accumulated in the stem base.Both Greviilea cultivars demonstrated the ability to convert the IBA to IAA. However, the rate of IBA metabolism appears to vary between cultivars and between tissues within the same cultivar. Between cultivars, the stem base of "Royal Mantle" cuttings metabolised IBA more than "Coastal Dawn". Since roots formed in the tissues which showed more IBA metabolism, i.e. in the stem base of "Royal Mantle" and in the upper stem of "Coastal Dawn", it is possible that root formation in Grevillea correlates with the cultivar's ability to metabolise IBA. These findings led to the conclusion that auxin distribution and metabolism might contribute to the different rooting abilities of Grevillea cultivars.

The objective of the present research was to evaluate the effect of different concentrations of indolebutyric acid (IBA) on the rooting of Luehea divaricata minicuttings under two different cultivation periods in a greenhouse environment. The minicuttings were immersed in a hydroethanolic solution containing IBA. All minicuttings survived after 30 and 60 days of cultivation. Root formation at 30 days of cultivation with 1000 mg L-1 of IBA was 91.7%, the same rate as that observed with 4000 mg L-1. At the 1000 mg L-1 concentration, the number of roots was the greatest among all treatments, with 8.42 roots per minicutting after 30 days of cultivation. After 30 days of cultivation, the formation and number of roots with the use of 1000 mg L-1 of IBA in the “pulse” treatment produced the best outcome results, allowing the plants to spend less time in a greenhouse at a reduced concentration of auxin when compared with other treatments. However, to obtain higher averages of secondary root formation, root length, and number of leaves, it is necessary to increase the cultivation period to 60 days. RESUMO: O objetivo do presente trabalho foi avaliar o efeito de diferentes concentrações do ácido indolbutírico (AIB) em dois períodos de cultivo em casa de vegetação sobre o enraizamento de miniestacas de Luehea divaricata. As miniestacas foram imersas por 10s em solução hidroetanólica contendo AIB. Todas as miniestacas sobreviveram tanto após 30 como 60 dias de cultivo. A formação de raízes aos 30 dias com 1000 mg L-1 de AIB foi de 91,7%, mesma média observada com 4000 mg L-1. Em relação ao número de raízes, novamente a concentração 1000 mg L-1destacou-se em relação às demais concentrações, e já aos 30 dias de cultivo houve 8,42 raízes por miniestaca. Aos 30 dias de cultivo, a formação e o número de raízes na presença de 1000 mg L-1 de AIB em tratamento “pulse” já produz resultados satisfatórios, permitindo que as plantas permaneçam menor tempo em casa de vegetação utilizando-se uma concentração reduzida de auxina, comparativamente àquelas que foram testadas. No entanto, para obter maiores médias de formação de raízes secundárias, comprimento das raízes e número de folhas é necessário prolongar o cultivo pelo período de 60 dias.

Adventitious roots (ARs) directly affect lotus seedling growth and product quality because principal root is not well developed. However, the details of AR formation at the molecular level have not been determined in lotus. Therefore, three stages were chosen to identify the change of proteins abundant during rhizome formation, using isobaric tags for relative and absolute quantization coupled with liquid chromatography–tandem mass spectrometry to gain insight into the molecular mechanisms involved in AR formation. We totally obtained 323,375 spectra during AR formation. After filtering to eliminate low-scoring spectra, 66,943 spectra, including 53,106 unique spectra, were identified. These unique spectra matched 28,905 peptides, including 24,992 unique peptides, which were assembled into 6686 proteins. In the C0/C1 and C1/C2 stages, 66 and 32 proteins showed enhanced abundance, and 173 and 73 proteins showed decreased abundance, respectively. Seventeen important AR formation-related proteins from the three stages were identified, and the expressions of nine genes from the above-identified proteins were assessed by qRT-PCR. This article provides a comprehensive understanding of the changes in metabolism during AR formation, and is helpful to accelerate the progress of breeding in fulture in lotus root.

A study was conducted to observe changes in mineral element concentrations within different sections of leafy stem cuttings of Hibiscus acetosella ‘Panama Red’ (PP20121) during a 21-day propagation period under standard industry propagation conditions. Concentrations of 13 mineral elements were analyzed in leaves, lower stems (below substrate), upper stems (above substrate), and roots at 3-day intervals. Before root emergence (day 0–6), P, K, Zn, Ca, and Mg concentrations decreased in the shoots (including upper stems and leaves), whereas Zn, Ca, and B concentrations decreased in the lower stems. Sulfur increase occurred in lower stems before root emergence. After rooting (day 9–21), N, P, Zn, Fe, Cu, and Ni concentrations decreased in the roots; K, S, B, and Mg concentrations increased. In the lower stems, N, P, K, S, and Zn concentrations decreased, whereas B increased. Potassium concentration decreased in the leaves; P, K, S, and Zn decreased in the upper stems. Calcium and Mg increased in leaves. This study indicates specific nutrients are important in adventitious rooting, and that it is important to analyze rooting as a function of fine-scale temporal measurements and fine-scale sectional measurements.

This study evaluated rooting of Pennisetum &lsquo, Vertigo&rsquo, cuttings and development and the nutritional status of rooted plants. Cuttings of Pennisetum &lsquo, rooted in a perlite or peat medium were treated with Go&euml, mar Goteo biostimulator as follows: (1) soaking (2) watering (3) spraying (4) no Goteo applied (control). Then, 83.3&ndash, 100% of cuttings formed adventitious roots. The, 100% rooting was obtained for plants in perlite when Goteo spraying or watering was used for plants rooted in peat only after Goteo watering application. Cuttings rooted in perlite had 30% more roots and they were longer than in peat. Goteo watering of cuttings affected root elongation in both peat and perlite. Neither rooting media nor biostimulator treatment affected root dry weight (DW). Rooting medium after 2 months of pot cultivation had no effect on biometric features of plants, but those grown from cuttings rooted in peat had a higher fresh weight (FW) compared to those rooted in perlite. Plants developed from Goteo-treated cuttings were higher compared to the control plants. Goteo watering during rooting stimulated the formation of new shoots in the greenhouse cultivation. Plants from cuttings rooted in perlite had more Fe and Cu in their leaves, especially when they were Goteo-watered. Goteo increased P content in plants derived from biostimulator-watered cuttings, and K in plants from cuttings soaked in Goteo and rooted in perlite.