Plant Disease Diagnostics

In Malaysia, we often hear that the agricultural sector will be transformed using biotechnology applications. However, not many understand or are aware of what biotechnology really entails and how its applications can be used in the agricultural sector. We have not heard concrete recommendations on how and which applications will be applied in this field. The main hurdle seems to be the level of knowledge on biotechnology among those who are responsible in developing agriculture. What is important is for officers at all levels and politicians to be exposed to basic biotechnology applications and its potential. Two and a half years have passed since the National Biotechnology Policy was launched with agriculture as the first thrust but we hardly hear of any breakthrough technology introduced to the farmers.

One area of research that is crucial to develop the agriculture sector is plant disease diagnostics. All our crops are threatened by a wide variety of plant diseases and pests. This causes huge loss to farmers and the industry due to damage to crops, lower fruit and vegetable quality, and even can wipe out entire harvest. About 42% of the world’s total agricultural crop is destroyed yearly by diseases and pests. Most of the time, farmers experience the attack of more than one pest or disease on their crops. The other problem is that some pests and pathogens (disease-causing agent) become resistant to the pesticides that are being used currently. However, crop losses can be minimised, and specific treatments can be tailored to combat specific pathogens if plant diseases are correctly diagnosed and identified early.

The traditional method of identifying plant pathogens is through visual examination. This is often possible only after major damage has already been done to the crop, so treatment will be of limited or no use. To save plants from irreparable damage by pathogens, farmers have to be able to identify an infection even before it becomes visible.

How is this possible? An attack by disease-causing organisms generates a complex immune response in a plant, resulting in the production of disease-specific proteins involved in plant defense and in limiting the spread of infection. For their part, pathogens also produce proteins and toxins to facilitate their infection. All this occurs even before the disease symptoms appear, so these molecules can be used for the development of plant diagnostic kits.

Advances in molecular biology, plant pathology, and biotechnology have made the development of such kits possible. These kits are designed to detect plant diseases early, either by identifying the presence of the pathogen in the plant (by testing for the presence of pathogen DNA) or the molecules (proteins) produced by either the pathogen or the plant during infection. These techniques require minimal processing time and are more accurate in identifying pathogens. And while some require laboratory equipment and training, other procedures can be performed on site by a person with no special training.

So far, diagnostic kits have been designed to detect diseases in crops such as rice, potatoes, papaya, tomatoes, and banana. Many pests and diseases are specific to Malaysia, thus there is a need for us to develop our own kits. Moreover, although there are many common pests and pathogens, different countries are plagued by different strains. This area of research will help farmers to reduce loss due to pests and diseases and increase productivity. This is one area that biotechnology can play a crucial role to transform our agricultural sector. Of course, there are many other areas as well that long for urgent attention that could create huge wealth and rebrand the agricultural sector. We should harness the full potential of the biological era instead of being complacent with our old ways of doing things and only create noise when there is a crisis. Agriculture is not about making snacks. That has been perfected by our forefathers. Let us move forward. My usual question: Do we want to be a leader or keep lagging behind in the biology revolution?

By Mahaletchumy Arujanan