ABSTRACT
Magnolia biondii Pamp is an important ornamental tree species widely grown and used as a rootstock in the propagation of different Magnolia varieties. In the current studies, anatomical, physiological and endogenous hormones were studied to check the effect of IBA 750 mg/L on the adventitious rooting and to provide theoretical and technical support for the propagation of Magnolia biondii Pamp through stem cuttings. Two thousand stem cuttings were prepared and divided into two groups i.e., IBA treated cuttings and water control. For the evaluation of antioxidant enzyme activities, and endogenous hormones levels, samples were collected on the day of planting and each 5th day and further steps were carried out in the laboratory according to the protocols and proper precautions. For the anatomical observations, samples were collected on the 13th, 15th, and 17th day for IBA treated cuttings while 21st, 23rd, and 25th day for control. Collected samples were preserved in the FAA solution and further observations were carried out in the laboratory. Anatomical observations showed that it took 13 days for the differentiation of root primordia to the appearance of young adventitious roots in IBA treated cuttings, while it took 21 days to develop primordia in the control. Antioxidant enzyme activities involved in ROS were significantly higher in the IBA treated cuttings compared to control. POD showed a peak on the 13th day before the emergence of roots in IBA treated cuttings while it showed a peak on the 21st day in the control. PPO showed a peak on the 21st day in the IBA treated cuttings while it showed a peak on the 29th day in the control. SOD showed a peak on the 17th day in IBA treated cuttings, while it showed a peak on the 25th day in the control. Exogenous application of IBA enhanced the endogenous IAA and GA3 levels compared to CK, while it reduced the levels of ABA continuously at the time of rooting and then increased gradually. Inclusively, our study suggests that IBA 750 mg/L is efficient for the rooting of Magnolia biondii Pamp cuttings, as it enhanced the process of antioxidant enzyme activities, endogenous hormones levels and reduced the time of root formation which is evident from the anatomical observations.
Magnolia biondii Pamp é uma importante espécie de árvore ornamental muito cultivada e utilizada como porta-enxerto na propagação de diferentes variedades de Magnolia. Nos estudos atuais, hormônios anatômicos, fisiológicos e endógenos foram estudados para verificar o efeito do AIB na dose de 750 mg / L no enraizamento adventício e fornecer suporte teórico e técnico para a propagação de M. biondii Pamp por meio de estacas. Duas mil estacas foram preparadas e divididas em dois grupos, ou seja, tratadas com AIB e controle de água. Para a avaliação das atividades das enzimas antioxidantes e dos níveis de hormônios endógenos, as amostras foram coletadas no dia do plantio e a cada 5 dias, enquanto as demais etapas foram realizadas em laboratório de acordo com os protocolos e os devidos cuidados. Para as observações anatômicas, as amostras foram coletadas no 13º, 15º e 17º dias para estacas tratadas com AIB e no 21º, 23º e 25º dias para o controle. As amostras coletadas foram preservadas em solução FAA, e outras observações foram realizadas em laboratório. Observações anatômicas mostraram a necessidade de 13 dias para a diferenciação dos primórdios radiculares até o aparecimento de raízes adventícias jovens em estacas tratadas com AIB e de 21 dias para o desenvolvimento dos primórdios no controle. As atividades das enzimas antioxidantes envolvidas nas ROS foram significativamente maiores nas estacas tratadas com AIB em comparação com o controle. A POD apresentou pico no 13º dia antes da emergência das raízes nas estacas tratadas com AIB, enquanto no 21º dia apresentou pico no controle. A PPO teve pico no 21º dia nas estacas tratadas com AIB e no 29º dia no controle. A SOD apresentou pico no 17º dia nas estacas tratadas com AIB e no 25º dia no controle. A aplicação exógena de AIB aumentou os níveis endógenos de IAA e GA3 em relação ao controle, enquanto reduziu os níveis de ABA continuamente no momento do enraizamento e, em seguida, aumentou gradativamente. Inclusive, nosso estudo sugere que o AIB na dose de 750 mg / L é eficiente para o enraizamento de estacas de M. biondii Pamp, visto que potencializou o processo de atividades de enzimas antioxidantes e os níveis de hormônios endógenos, além de reduzir o tempo de formação de raízes, o que fica evidente nas observações anatômicas.
Subject(s)
Magnolia/growth & development , HormonesABSTRACT
Abstract Magnolia biondii Pamp is an important ornamental tree species widely grown and used as a rootstock in the propagation of different Magnolia varieties. In the current studies, anatomical, physiological and endogenous hormones were studied to check the effect of IBA 750 mg/L on the adventitious rooting and to provide theoretical and technical support for the propagation of Magnolia biondii Pamp through stem cuttings. Two thousand stem cuttings were prepared and divided into two groups i.e., IBA treated cuttings and water control. For the evaluation of antioxidant enzyme activities, and endogenous hormones levels, samples were collected on the day of planting and each 5th day and further steps were carried out in the laboratory according to the protocols and proper precautions. For the anatomical observations, samples were collected on the 13th, 15th, and 17th day for IBA treated cuttings while 21st, 23rd, and 25th day for control. Collected samples were preserved in the FAA solution and further observations were carried out in the laboratory. Anatomical observations showed that it took 13 days for the differentiation of root primordia to the appearance of young adventitious roots in IBA treated cuttings, while it took 21 days to develop primordia in the control. Antioxidant enzyme activities involved in ROS were significantly higher in the IBA treated cuttings compared to control. POD showed a peak on the 13th day before the emergence of roots in IBA treated cuttings while it showed a peak on the 21st day in the control. PPO showed a peak on the 21st day in the IBA treated cuttings while it showed a peak on the 29th day in the control. SOD showed a peak on the 17th day in IBA treated cuttings, while it showed a peak on the 25th day in the control. Exogenous application of IBA enhanced the endogenous IAA and GA3 levels compared to CK, while it reduced the levels of ABA continuously at the time of rooting and then increased gradually. Inclusively, our study suggests that IBA 750 mg/L is efficient for the rooting of Magnolia biondii Pamp cuttings, as it enhanced the process of antioxidant enzyme activities, endogenous hormones levels and reduced the time of root formation which is evident from the anatomical observations.
Resumo Magnolia biondii Pamp é uma importante espécie de árvore ornamental muito cultivada e utilizada como porta-enxerto na propagação de diferentes variedades de Magnolia. Nos estudos atuais, hormônios anatômicos, fisiológicos e endógenos foram estudados para verificar o efeito do AIB na dose de 750 mg / L no enraizamento adventício e fornecer suporte teórico e técnico para a propagação de M. biondii Pamp por meio de estacas. Duas mil estacas foram preparadas e divididas em dois grupos, ou seja, tratadas com AIB e controle de água. Para a avaliação das atividades das enzimas antioxidantes e dos níveis de hormônios endógenos, as amostras foram coletadas no dia do plantio e a cada 5 dias, enquanto as demais etapas foram realizadas em laboratório de acordo com os protocolos e os devidos cuidados. Para as observações anatômicas, as amostras foram coletadas no 13º, 15º e 17º dias para estacas tratadas com AIB e no 21º, 23º e 25º dias para o controle. As amostras coletadas foram preservadas em solução FAA, e outras observações foram realizadas em laboratório. Observações anatômicas mostraram a necessidade de 13 dias para a diferenciação dos primórdios radiculares até o aparecimento de raízes adventícias jovens em estacas tratadas com AIB e de 21 dias para o desenvolvimento dos primórdios no controle. As atividades das enzimas antioxidantes envolvidas nas ROS foram significativamente maiores nas estacas tratadas com AIB em comparação com o controle. A POD apresentou pico no 13º dia antes da emergência das raízes nas estacas tratadas com AIB, enquanto no 21º dia apresentou pico no controle. A PPO teve pico no 21º dia nas estacas tratadas com AIB e no 29º dia no controle. A SOD apresentou pico no 17º dia nas estacas tratadas com AIB e no 25º dia no controle. A aplicação exógena de AIB aumentou os níveis endógenos de IAA e GA3 em relação ao controle, enquanto reduziu os níveis de ABA continuamente no momento do enraizamento e, em seguida, aumentou gradativamente. Inclusive, nosso estudo sugere que o AIB na dose de 750 mg / L é eficiente para o enraizamento de estacas de M. biondii Pamp, visto que potencializou o processo de atividades de enzimas antioxidantes e os níveis de hormônios endógenos, além de reduzir o tempo de formação de raízes, o que fica evidente nas observações anatômicas.
ABSTRACT
Lignin is the second most abundant renewable biopolymer on earth after cellulose. It is being used in many industrial applications due to its abundance. In the present study, lignin was isolated from the stems of Leucaena leucocephala (Lam.) de Wit., a high biomass yielding plant using acidic dioxane under N2 atmosphere. Structural characterization of isolated dioxane lignin (DL) was performed by analytical techniques: UV, FT-IR, 1H NMR and 13C NMR. Their monolignol content was determined by nitrobenzene oxidation followed by HPLC-MS/MS analysis. The data was compared with commercial alkali lignin (AL). The results showed that DL is of hardwood guaiacyl-syringyl (GS) type, whereas AL is softwood type with more guaiacyl units and trace amounts of p-hydroxyphenyl units (H). Thermogravimetric analysis (TGA) of DL showed two stage thermal degradation profile similar to AL. The DTGmax for DL and AL were found in the second major loss event of second stage of TGA at 424°C and 404°C, respectively. Differential scanning calorimetry (DSC) study exhibited the glass transition temperatures (Tg) at 132°C and 122°C for DL and AL, respectively. The results from thermal stability studies suggest that dioxane lignin isolated from the "miracle tree" (subabul) can be exploited in various thermoplastic industrial applications.
ABSTRACT
Casuarina equisetifolia Forst. is a tree crop that provides fuel wood, land reclamation, dune stabilization, and scaffolding for construction, shelter belts, and pulp and paper production. C. equisetifolia fixes atmospheric nitrogen through a symbiotic relationship with Frankia, a soil bacterium of the actinobacteria group. The roots of C. equisetifolia produce root nodules where the bacteria fix atmospheric nitrogen, which is an essential nutrient for all plant metabolic activities. However, rooted stem cuttings of elite clones of C. equisetifolia by vegetative propagation is being planted by the farmers of Pondicherry as costeffective method. As the vegetative propagation method uses inert material (vermiculite) for rooting there is no chance for Frankia association. Therefore after planting of these stocks the farmers are applying 150 kg of di-ammonium phosphate (DAP)/acre/year. To overcome this fertilizer usage, the Frankia-inoculated rooted stem cuttings were propagated under nursery conditions and transplanted in the nutrient-deficient soils of Karaikal, Pondicherry (India), in this study. Under nursery experiments the growth and biomass of C. equisetifolia rooted stem cuttings inoculated with Frankia showed 3 times higher growth and biomass than uninoculated control. These stocks were transplanted and monitored for their growth and survival for 1 year in the nutrient-deficient farm land. The results showed that the rooted stem cuttings of C. equisetifolia significantly improved growth in height (8.8 m), stem girth (9.6 cm) and tissue nitrogen content (3.3 mg g−1) than uninoculated controls. The soil nutrient status was also improved due to inoculation of Frankia.
ABSTRACT
The effects of plant growth promoting rhizobacteria (PGPR) on the rooting and root growth of semi-hardwood and hardwood kiwifruit stem cuttings were investigated. The PGPR used were Bacillus RC23, Paenibacillus polymyxa RC05, Bacillus subtilis OSU142, Bacillus RC03, Comamonas acidovorans RC41, Bacillus megaterium RC01 and Bacillus simplex RC19. All the bacteria showed indole-3-acetic acid (IAA) producing capacity. Among the PGPR used, the highest rooting ratios were obtained at 47.50 percent for semi-hardwood stem cuttings from Bacillus RC03 and Bacillus simplex RC19 treatments and 42.50 percent for hardwood stem cuttings from Bacillus RC03. As well, Comamonas acidovorans RC41 inoculations indicated higher value than control treatments. The results suggest that these PGPR can be used in organic nursery material production and point to the feasibility of synthetic auxin (IBA) replacement by organic management based on PGPR.