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Myrtle rust disease is a vital fungal plant disease caused by Puccinia psidii fungi and mostly affecting the plants of the Myrtaceae family. The disease is highly destructive and disastrous as it is rapidly spread courtesy of its potential to produce numerous spores, spreadable by the wind, humans or animals, making it difficult to control (Tan, Collins, Chen, Englezou & Wilkins, 2014). The most affected parts of the plant are the actively growing leaves, shoots, fruits, bud and flowers. Therefore, some of the techniques should be employed such as the nucleic acid detection techniques should be imposed and implemented in the control and even treatment of the disease. Due to the high resistance genes embedded on the disease some nucleic acid detection techniques can be carried out to determine the size and the composition of the myrtle rust genome and its taxonomic status (Tan et al, 2014).

One of the techniques used is the use of the film detecting methods for tritium-Labeled proteins and nucleic acids in polyacrylamide gels. This method detects the 3H in polyacrylamide gels by scintillation autograph using x-ray film. The gel is dehydrated in dimethyl sulphoxide, soaked in a solution of 2,5-diphenyloxazole (PPO) in dimethylsulphoxide. It is then dried and exposed to RP Royal “X-Omat” film at -70 “C. The β-particles from 3H interact with the 2,5-diphenyloxazole emitting light which causes local blackening of an X-ray film (Bonner & Laskey, 1974). Therefore, the spores produced by the myrtle rust disease can be examined through this method to identify its content. The gel, in this case, can be the spores of myrtle rust. The detection efficiency of 3H on paper can be increased by inserting the chromatograms with a scintillator before applying the film. Thus, the film is not exposed by the β-particles themselves, but by light generated by the interaction of the β-particles with 2,5-diphenyloxazole (PPO). Proteins available in the spore can be labeled and identified by using a solution of 0.1%coomassie blue in 30% methanol-10% acetic acid (Bonner & Laskey, 1974).

. The procedures of the method are therefore followed on the spores. once the electrophoresis us complete, the gel is soaked in about 20 times its volume of sulphoxide (Me2SO) for 30 minutes followed by 30 minutes immersion in fresh Me2SO. The next step includes Immersing the gel in 4 volumes of 20% (w/w) PPO in Me2SO (22.2%, w/v) for 3 h. Then Immerse the gel in 20 volumes of water for 1 hour. Subsequently, dry the gel under vacuum for one hour. Lastly Place RP Royal “X-Omat” or equivalent Medical X-ray film in contact with the dried gel and expose at -70 “C. by passing the gel through the process determination of 14C and 35S are obtain in slab gels by autoradiography.According to Bonner & Laskey (1974), when the β-particles are converted to light in situ by PPO this difference is greatly reduced. Thus, the efficiency of direct autoradiographic detection of β-particles from 14C or 35S in polyacrylamide gels is so low that conversion of β-particles to light by PPO causes a ten-fold improvement, permitting the design of experiment with far smaller amounts of radioactivity. More so, 3H isotopes are also detected in the spores from the process 3000 dis. 3H/min in a band 1 x 0.1 cm will detectably blacken RP Royal “X-Omat” film in 24 h at -70 “C. Bands containing 500 dis. 3H/min can be detected in one-week exposures (Bonner & Laskey, 1974).

When the process is concluded, the information can be interpreted in deferent ways. One of the methods of interpretation is through graphical methods. Plotting the variance in the graph simplifies the understanding. Another way of representation is by use of table content, and lastly one can represent the information in image forms from the x-rays (Rabilloud, 2012).

From the technique, the nucleotide sequence of the spores of the myrtle rust diseases are established and it genetic markers. This further, gives the up the proteins for DNA integration and RNA- dependent. This leads to finding ways and solutions for the control of the disease. This can involve study on the formulation of fungicide that can eradicate the high resistance gene present in Myrtle rust disease (Rabilloud, 2012).

The most impressive thing about the technique is that it is among the most efficient methods of determining the nucleic acids in gels. Nevertheless, the process is excellent and advisable for the poorly soluble proteins such as the membrane proteins. The yield of 2D electrophoresis has been found to be rather moderate (20-40%) depending on the class of protein as well as the efficiency of sample preparation. Through this process also one can detect motifs on gel separated proteins such as sugar or phosphates group offering a very palette of detection schemes with broad versatility (Rabilloud, 2012).

The technique has some limitations; one of the limitations is the high biological variability that makes it very difficult to find all protein spots showing a statistically significant variation in the process. This is due to fluorescent molecules are bound per protein molecules resulting, in general, low intensity for many proteins. Furthermore, the process is associated with more time consuming and cumbersome process that includes the image reproducibility that is a very complex process (Rabilloud, 2012).


Bonner, W. M., & Laskey, R. A. (1974). A Film Detection Method for Tritium‐Labelled Proteins and Nucleic Acids in Polyacrylamide Gels. European Journal of Biochemistry46(1), 83-88.

Tan, M. K., Collins, D., Chen, Z., Englezou, A., & Wilkins, M. R. (2014). A brief overview of the size and composition of the myrtle rust genome and its taxonomic status. Mycology5(2), 52-63.

Rabilloud, T. (2012). The whereabouts of 2D gels in quantitative proteomics. In Quantitative Methods in Proteomics (pp. 25-35). Humana Press.