Study on in vitro propagation of Sophora tonkinensis Gagnep through stem node culture

In the present study, authors propagated Sophora tonkinensisGagnep plants using stem nodal culture. The results indicated that on MS medium supplemented with 30 g/l sucrose, 5.5 g/l agar, 200 ml/l coconut water, 1 g/l activated charcoal, 0.75 mg/l TDZ shoots proliferated from stem segments have the best count and height of shoots. The most appropriate medium for multiplication of shoots was the MS medium supplemented with 30 g/l sucrose, 5.5 g/l agar, 200 ml/l coconut water, 1 g/l activated charcoal, 0.75 mg/l TDZ, 0.5 mg/l IBA, 2.0 g/l peptone, 30 g/l carrot puree, pH 5.5 with the results of 20.60 shoots/explant, shoot height of 3.75 cm and 4.6 leaves/shoot after 8 weeks of culture. Root formation of shoots carried out on the MS medium supplemented with 30 g/l sucrose, 5.5 g/l agar, 200 ml/l coconut water, 1 g/l activated charcoal, 1.0 mg/l αNAA gave the best result. In the nursery, a mixture of humus + coconut fiber powder (70:30 ratio) was regarded as the best substrate due to the high survival rate of plantlets (92%) and healthy plantlets (10.30 cm high with 7.2 leaves and 4.3 new roots/a plantlet) at 10 weeks after planting

HISTOPLASMOSIS IN NON-HIV IMMUNOCOMPROMISED PATIENT RESIDING IN A NON-ENDEMIC AREA IN BRAZIL

Introduction: Histoplasmosis is a fungal disease, caused by Histoplasma capsulatum. Goal: To report a case of an immunocompromised patient with diagnosis of histoplasmosis in a non-endemic region. Methodology: Case report. Case report: Patient carrier of rheumatoid arthritis, makes continuous use of methotrexate and has reported contact with large amount of bat guano. Result of cervical lymph node culture was positive for H. capsulatum. Discussion: The infection was presented related to drug-induced immunosuppression in a non-endemic area. Conclusion: In view of the location where the infection occurred, the geographic expansion of the disease and the importance of this report for the literature are clear.

RECENT ADVANCEMENT ON ISOLATION, ACTIVATION AND CRYOPRESERVATION OF LYMPH NODE CELLS IN MICE.

ABSTRACT Lymph nodes are found within the body has B, T and other immune cells and help to filter and trap foreign particles. Like any other primary culture lymph node culture would retain many of differentiated characteristics of cells in vivo thus they have potential for acting as alternative method to mammalian model. For setting up primary lymph node culture in mice different types of lymph nodes were collected from mice followed with isolation, activation and cryopreservation of cells from lymph node. The present review emphasize on various procedures used for isolation, activation and cryopreservation of lymph node cells. Isolation of cells was performed by collagenase digestion, teasing apart of lymph node using dissecting needle or lymph nodes were disrupted between two frosted slides. Concanavalin A have been widely used to stimulate mice lymph node cells. Low dose of Con A have stimulatory effect on T cells but high dose have inhibitory action and caused suppression of proliferation of T cell. Balb/c mice and C57Bl/6 mice were used for different dose of Con A. The addition of cryoprotective agents, e.g.dimethylsulphoxide and careful control of cooling rates affords protection from cell damage during freezing.

Improved node culture methods for rapid vegetative propagation of switchgrass (Panicum virgatum L.)

Background Switchgrass (Panicum virgatum L.) is an important bioenergy and forage crop. The outcrossing nature of switchgrass makes it infeasible to maintain a genotype through sexual propagation. Current asexual propagation protocols in switchgrass have various limitations. An easy and highly-efficient vegetative propagation method is needed to propagate large natural collections of switchgrass genotypes for genome-wide association studies (GWAS). Results Micropropagation by node culture was found to be a rapid method for vegetative propagation of switchgrass. Bacterial and fungal contamination during node culture is a major cause for cultural failure. Adding the biocide, Plant Preservative Mixture (PPM, 0.2%), and the fungicide, Benomyl (5 mg/l), in the incubation solution after surface sterilization and in the culture medium significantly decreased bacterial and fungal contamination. In addition, “shoot trimming” before subculture had a positive effect on shoot multiplication for most genotypes tested. Using the optimized node culture procedure, we successfully propagated 330 genotypes from a switchgrass GWAS panel in three separate experiments. Large variations in shoot induction efficiency and shoot growth were observed among genotypes. Separately, we developed an in planta node culture method by stimulating the growth of aerial axillary buds into shoots directly on the parent plants, through which rooted plants can be generated within 6 weeks. By circumventing the tissue culture step and avoiding application of exterior hormones, the in planta node culture method is labor- and cost-efficient, easy to master, and has a high success rate. Plants generated by the in planta node culture method are similar to seedlings and can be used directly for various experiments. Conclusions In this study, we optimized a switchgrass node culture protocol by minimizing bacterial and fungal contamination and increasing shoot multiplication. With this improved protocol, we successfully propagated three quarters of the genotypes in a diverse switchgrass GWAS panel. Furthermore, we established a novel and high-throughput in planta node culture method. Together, these methods provide better options for researchers to accelerate vegetative propagation of switchgrass.

Effect of plant growth regulators on plant regeneration of hyacinth bean (Lablab purpureus (L.) Sweet) through nodal explants

Nodal explants of three accessions namely BD-101, BD-122 and BD-8001 of hyacinth bean (Lablab purpureus (L.) Sweet) were cultured for four weeks on MS medium supplemented with different concentrations and combinations of NAA (0, 0.1 mgl-1) and BAP (0.5, 1.0 and 2.5 mgl-1) for plant regeneration. The highest shoot initiation was observed in 0.5 mgl-1 BAP while the lowest shoot initiation was found in 2.5 mgl-1 BAP with 0.1 mgl-1 NAA. Earlier shoot initiation was exhibited in 0.5 mgl-1 BAP with 0.1 mgl-1 NAA. The highest number of leaflets and higher shoot lengths were observed in MS medium. Comparatively higher number of shoots was found in BAP (0.5-2.5 mgl-1). The highest percentage of callus was initiated in medium supplemented with 1.0 mgl-1 BAP. Earlier callus initiation and larger callus size were found in combination of BAP (0.5-2.5 mgl-1) with 0.1 mgl-1 NAA. BD-122 cultured in MS medium was found superior for shoot regeneration through node culture. Four different concentrations of IBA (0.1-1.5 mgl-1) were used for rooting. The highest percentage (86.67 %) of rooting was found in MS medium containing 0.1 mgl-1 IBA at four weeks. Rooting frequency decreased with the increasing concentration of IBA. The accession BD-8001 had 99.60 % rooting in 0.5 mgl-1 IBA. The highest number of longest roots was exhibited in 0.1 mgl-1 IBA. The regeneration protocol developed from nodal explants has applicability in improvement of hyacinth bean. Bangladesh J. Agril. Res. 44(1): 27-42, March 2019

Shoot multiplication via elongated stem node culture under darkness: a novel method in micropropagation of Paphiopedilum villosum

Paphiopedilum villosum is a beautiful orchid species and has high value in trade; however, this is one of the most difficult to propagate orchids. So far, there has been very little publication on micropropagation. In this study, the effects of plant growth regulators on shoot regeneration from stem node culture of elongated P. villosum shoots in the darkness were investigated. Shoots (1.5 cm) were elongated and produced individual stem nodes under darkness condition for 3 months. Stem nodes were cultured on SH medium and supplemented with individually BA, KIN or TDZ to investigate shoot regeneration. The shoot multiplication rate was also recorded in this study. The highest stem node was observed in the dark with 5.25 cm in the height and the number of stem nodes were 3 stem nodes/shoot. The isolated stem node was cultured on SH medium supplemented with 30 g/L sucrose, 8 g/L agar, 1 g/L charcoal and different concentrations of BA, KIN, TDZ. The results observed after 3 months showed that the best shoot regeneration rate (85%) and highest shoot multiplication coefficient (6.6 shoots/stem node) was obtained when shoots derived from stem node were cultured on SH medium supplemented with 0.5 mg/L TDZ, 30 g/L sucrose, 8 g/L agar and 1 g/L charcoal. Those shoots obtained in the above treatments were subcultured on MS medium supplemented with 0.3 mg/L NAA for rooting and gave the highest number of roots (6.6 roots/shoot) after 1 month; and these plantlets were acclimatized in Taiwan sphagnum moss and transferred into greenhouse with the best survival rate (100%) after 3 months.