A Wonderful Expedition to The Botanical Garden, University of Ibadan: Collection of Leaves

By: Queendaline Ebere Nwofor

 

Our journey towards Ficus phyllospheres started at the front gate of the University of Ibadan’s Botanical garden on the 5th of November 2015.  The garden is rich, diverse and a distance from the working laboratory but I was not tired of going there because the garden was a worthy reward. The garden is fascinating and serene with abundant ‘first class’ fresh air and smooth floor which tempted me to sit for a while. Thank God for the ever-helpful garden attendants especially Mr. Sam for his patience and readiness to provide answers to my questions. I wish I could be allowed a little time out in the garden on weekly basis.

 

THE PLANTS

The plants of interest are Ficus natalensis and Ficus mucoso.

These plants belong to angiosperm kingdom and of the family Moraceae.

           

Figures 1-3.  The leaves, branches and stems of Ficus natalensis respectively.

 

FICUS NATALENSIS         

Ficus natalensis is in the ornamental section of the University of Ibadan Botanical garden.  It is commonly known as the Natal fig,(Pooley, 1993). The species name ‘natalensis’ refers to the plant’s place of origin in Natal, a province in eastern South Africa. The tree is quite robust with intertwining and bridging of trunk and branches and a wide-spreading crown. It has multiple branches with aerial roots that spread down and weld with the trunk. The leaves are relatively small, smooth and thick with parallel venation, evergreen and smooth while the bark is quite smooth and dark grey. I was told that the tree is grown for many reasons such as wind break. It was also stated that it can grow higher than we met it to attain heights of over 20m, with a very extensive canopy if left and can live for a hundred years.   What an amazing plant!

    

Figures 4 and 5. The leaves on the branches and the stem of Ficus mucoso respectively. F.  mucoso is in the arboretum section of the garden.

 

      

 

FICUS MUCOSO

We met this species as a free-standing tree which forms the garden canopy in association with other trees. It has very pale orange coloured bark. The leaves have a fairly netted venation, are rough to touch and have cordate bases. At each node, there is a ring of hairs on the scar left by the fallen stipule. It had no fruits at the time of collection but is known to produce fruits called ‘figs’ which could measure between 3–4 cm wide. On breaking a twig   a sticky white latex exuded and amazingly turned pale orange after a short while unlike every other leaf I had plucked in the past.

 

 

 

 

 

 


 

MY EXPERIENCE WITH POLYMERASE CHAIN REACTION (PCR)

By: Anderson Osemuahu Oaikhena

As part of our Master of Science degree program, we set out to isolate and identify the bacteria living on the leaf of Ficus natalensis, an African medicinal plant used locally to treat a variety of bacterial infections. This was done as a class project and the entire class was divided into groups of two. Our hypothesis was that the organisms living on this great reserve of phytochemicals would have intrinsic resistance to the active constituents.  As part of the process of identifying the bacteria associated with the leaf, we undertook a culture independent analysis of the leaf’s microbiome. We extracted DNA of the microorganisms on the surface of the leaf   using the Mo Bio Power Soil DNA Isolation Kit.

 


   

Figure 6. Agarose gel after electrophoresis where lane 2 is the band for control 

   

After the DNA extraction, we set up a PCR to amplify 16S rRNA genes but to my utmost surprise, after electrophoresis, we didn’t get our desired band. I need to state at this point that this was my first PCR ever. I had read about PCR, prior to this laboratory course, and just saw it as a straight forward process which would always yield results. Thus, I wasn’t prepared for this disappointment; I expected everything to go exactly as planned. Why didn’t I get a band on my gel? The PCR set-up obviously was not the problem as our positive and negative controls yielded satisfactory results. What then could be the problem, I thought to myself. Could it be that our DNA extraction process was faulty or could it be that our primers weren’t complementary to the DNA present in the sample? Could it be that there were no bacteria on the leaves? These and some other questions I asked as I yearned for a solution.

 

We weren’t going to give up easily despite the seemingly dissatisfactory results, at least not without troubleshooting to find out what went wrong. A part of me wished this wasn’t going to be the end as there were some other downstream applications from which I would accrue vast practical knowledge and experience. What a moment of confusion! At this point my Professor intervened. She had so much confidence in the power soil extraction kit and insisted


   

Figure 7. Agarose gel showing DNA bands. Lane 3 shows a band of the highly sought after PCR product. Lane 4 is the band of positive.

 

   

that there is most likely DNA in the sample but possibly, the concentration was too small to be visualized without amplification. Also, from our culture dependent study we found that the leaf was sparsely colonized, correlating that the DNA in the sample would likely be small. She suggested we set up another PCR, this time with a different pair of 16S rRNA primers and more volume of DNA sample. That’s one of the great differences between an amateur and an experienced researcher. My professor never gave up! She always thought of a way forward.

 

After amplification and electrophoresis, the much-dreaded time came to view the gels and I had mixed feelings. You ought to have seen the expectancy on my face as we put the gel in the transilluminator. I had seen too much disappointment, I thought, and I just couldn’t bear the thought of another. Of course, this time, my precious 1.5 Kb band of interest showed up and my heart was filled with joy! What a great relief!

 

This experience went a great deal in making me realize that hurdles are inevitable in research, there is bound to be something unexpected. The fact that we had to trouble shoot on a few occasions made the entire process interesting. Just a little more thought and effort led to the desired results.

Indeed, it was an experience to be remembered, especially for a beginning researcher like me.