Natural Sciences
Mak Scientists Unveil New Method of Measuring Stress Levels in Plants
Just like animals and human beings, plants too can be stressed. Whereas one may easily detect stress in animals and humans basing on their behavior, plant “behavior” is not easy to interpret.
Why should we be concerned about stress in plants?
Plants under stress cannot reproduce or grow well because they have to divert much of their physiological energy to fighting stress. If the plants are critical food crops, this will lead to perpetual food shortages because their energy resources are spent fighting stress.
New study on measuring stress in plants
A new study titled “Sandwich Enzyme-Linked Immunosorbent Assay for Quantification of Callose” and led by a team of scientists at the Department of Plant Sciences, Microbiology and Biotechnology at Makerere University in collaboration with the University of California, Davis, USA, shows how stress in plants can be measured. According to Prof. Arthur Tugume, the lead scientist of this study and expert in plant diseases, when plants are stressed, they produce numerous molecules within their cells mostly as means of adapting to stress or avoiding the impact of stress. “For example, plants produce reactive oxygen species like hydrogen peroxide, superoxide ions, and hydroxyl ions. These reactive oxygen species are produced rapidly and act as rapid messengers in the plant tissues to activate additional responses spreading over the entire plant body. This helps the plant to withstand or avoid the impact of stress”.
Dr. Ssenku E. Jamilu, a plant physiology expert on the team explains that in plants, stress can be induced by many factors such as pollution in the soil and atmosphere, high soil salinity (salt stress), excessive lack of water (drought), extreme temperatures, lack of oxygen (anoxia), excess radiation, mechanical injury by wounding or by pests that feed on the plants, and infestation by disease-causing microorganisms (pathogens). “Such factors are worsened by climate change, implying the importance of measuring their impact on individual plants to guide plant breeding programmes to ensure sustainable food production in the face of climate change”.
The research indicates that reactive oxygen species set in motion additional processes to ensure limited impact of stress on the plant. For example, a unique carbohydrate, named “callose” starts to accumulate in large quantities within plant cells as a means of fortifying plant cells. Callose differs from the other usual plant carbohydrates such as starch or cellulose because of the way its structures are formed. Also, the production of callose gets increased during stress. Callose acts as a road-block to any pathogen such as bacteria by limiting bacterial movement that would otherwise ease attack on other tissues or cells.
“If we can artificially induce the stress on the plant, and then measure the amount of reactive oxygen species or callose or any other responses in the plant, we should be able to directly and quantitatively measure the stress,” Prof. Tugume explains.
He however notes that callose participates in many other normal developmental processes of plants and for that reason, there is always some “housekeeping” callose in the plant tissues even without stress. “This means that one must be able to accurately and quantitatively distinguish between ‘stress-induced’ and normal ‘housekeeping’ callose”.
In this study, the researchers used young (2.5-months old) banana plantlets that had been generated from tissue culture at Kawanda Agricultural Research Institute. They then infected the plantlets with a bacterium called Xanthomonas campestris pv. musacearum. This bacterium induces so much stress on the banana plants resulting into a destructive disease known as banana xanthomonas wilt (BXW), the most destructive disease of bananas in East and Central Africa.
The banana leaves, pseudostems and corms were analyzed for callose and compared with the control plants that had been inoculated with water instead of bacteria. The analysis was done using a method called S-ELISA (Sandwich Enzyme-linked immunosorbent Assay), that was designed by scientists in this study. This method is specific to callose.
Callose-specific primary antibodies were used to coat the wells of 96-well microplates followed by incubation with callose extracts from tissues of stressed plants. Additional incubation with same primary callose-specific antibodies was done, and finally, incubation with a secondary antibody that is conjugated to an enzyme. When a substrate is supplied to the enzyme, colour changes were monitored. The presence of callose (and thus stress on the plants) was assessed quantitatively by measuring the intensity of color change resulting from enzymatic action on the substrate. This method proved effective in comparison to the gold standard method of detecting and quantifying aniline blue stained callose using fluorescence microscopy.
This research was part of the PhD studies for Mr. Abubakar S. Mustafa at Makerere University and University of California, Davis. According to Mr. Mustafa, his method is new and can be applied to any plant that is subjected to any stress because generally, plants produce callose in response to stress.” Mr. Mustafa further states that the method is convenient because, if necessary, samples can be processed between a few hours to one year (or even longer), which allows exchange of materials between laboratories and countries when needed, something that was not possible before. The S-ELISA method used 96-well plates which allows high throughout studies, hence, hundreds of samples can be analyzed simultaneously within a few days.
This study has been published as a Protocol by Multidisciplinary Publishing Institute (MDPI) in an open access journal, “Methods and Protocols”, in the section: Biochemical and Chemical Analysis & Synthesis and is freely accessible on https://www.mdpi.com/2409-9279/5/4/54/htm.
The research was funded by the Bill and Melinda Gates Foundation through the National Agricultural Research Organization (NARO), Uganda. The project had partners including the International Institute of Tropical Agriculture, the Alliance for Bioversity International and International Centre for Tropical Agriculture (CIAT) and CABI.
For more details, contact;
- Prof. Arthur Tugume, Lead Scientist of the study, College of Natural Sciences, Makerere University, Email: arthur.tugume@mak.ac.ug, Tel: +256772514841
- Mr. Abubakar S. Mustafa, Co-Author and PhD student on the study, Email: mustafa.abubakar.sadik@gmail.com, Tel: +256702813233
- Hasifa Kabejja, Principal Communication Officer, College of Natural Sciences, Makerere University, Email: pr.cns@mak.ac.ug, Tel: +256774904211
Natural Sciences
Preparing Graduates for Life after University: CoNAS Launches Terminal Seminar for Final Year Students
Relevance of the seminar
Transitioning from university life to the professional world can be a daunting experience for many graduates. This challenge is particularly pronounced in Uganda, the broader East African region, and across Africa, where many university leavers find themselves ill-equipped to face the realities of life after school. Issues such as limited career guidance, lack of personal development resources, and insufficient awareness of societal expectations leave many graduates unprepared for what lies ahead.
According to data from the Uganda Bureau of Statistics (UBOS), the youth unemployment rate in the country stands at approximately 13.3%. Each year, over 400,000 graduates join the job market, all vying for a mere 9,000 available formal employment opportunities. This staggering imbalance creates a climate of intense competition, often resulting in widespread disillusionment, anxiety, and in severe cases, depression – largely due to the absence of structured transition programmes to support young people during this critical phase of life.
While some graduates manage to find employment, launch entrepreneurial ventures, or pursue further academic study, many others struggle with prolonged unemployment or underemployment. This vulnerable group is at risk of turning to detrimental coping mechanisms such as substance abuse, criminal activity, or social withdrawal. One of the root causes of this unpreparedness is the lack of mentorship and real-world guidance in key areas such as workplace conduct, professional ethics, entrepreneurship, leadership, and personal financial management.
In response to this pressing need, the College of Natural Sciences (CoNAS) at Makerere University, through its School of Biosciences, has launched an innovative initiative – the Terminal Seminar/Symposium for Final-Year Students. Spearheaded by Heads of Departments within the School, the seminar is designed to bridge the gap between academic knowledge and the realities of post-university life by equipping students with essential life and career skills.
Objectives of the Terminal Seminar
The seminar aims to:
- Impart practical knowledge on workplace ethics, professional behaviour, and employability.
- Cultivate entrepreneurial thinking and leadership skills, enabling students to create their own opportunities.
- Provide strategies for coping with unemployment, social pressure, and the transition period.
- Raise awareness about mental health and equip students with tools to manage transition-related stress.
- Offer insights into navigating employment in public and private sectors, non-governmental organizations (NGOs), and the global job market.
Expected Outcomes
By the end of the programme, students are expected to:
- Gain a broader awareness of career and self-employment opportunities.
- Develop realistic expectations about the challenges and opportunities post-university.
- Experience reduced levels of frustration and vulnerability to harmful behaviours.
- Build connections and networks with industry professionals and mentors.
2025 Terminal Seminar Event Highlights
On 23rd April 2025, CoNAS held its flagship Terminal Seminar for Final Year students set to complete their studies in June 2025. The seminar was coordinated by Dr. Godfrey Kawooya Kubiriza, Head, Department of Zoology, Entomology, and Fisheries Sciences, with support from Dr. Barbra Nerima and Dr. Joel Isanga, both faculty members from the Department of Biochemistry and Systems Biology.
The event featured a series of empowering sessions, designed to help students navigate the transition from academic life to the professional world. Key topics included career planning, workplace ethics, entrepreneurship, and mental well-being.
A line-up of seasoned professionals and motivational speakers – including Mr. John Walugembe, Executive Director of the Federation of Small and Medium Sized Enterprises Uganda, and Dr. Catherine Mbidde, Ag Director, Makerere University Innovations Pod (UniPod), also Lecturer at the School of Business at CoBAMS, shared their personal journeys, professional insights, and practical advice for thriving beyond the university walls. Other Speakers included Dr. Alex Behakanira from the Department of Mathematics, Makerere University; Mr. Henry Nsubuga, Manager, Counselling and Guidance Centre, Makerere University; Mr. Maurice Ssebisubi, Senior Programme Officer (Fisheries and Environment) at the Embassy of Iceland; and Ms. Sylvia Kajubi, Deputy Principal at the Insurance Training College of Uganda.
Sharing his personal journey, Mr. John Walugembe offered valuable insights to students, emphasizing the critical importance of time management in shaping a successful career. He encouraged them to cultivate patience, resilience, and integrity as they transition from academic life into the professional world.
Mr. Walugembe also urged the students to maintain an open mind when approaching the job market. “You should not confine yourselves to roles within your academic fields. Remain open to exploring a wide range of opportunities that may arise. You need to approach the job market with flexibility,” he advised.
In addition, he highlighted the dual significance of academic excellence and strong professional networks, noting that good grades can open doors, but relationships and connections often determine how far one can go in their career journey. “The best way to build networks is to improve your value,” he advised.
Addressing the students on how to leverage the digital landscape to advance their careers, Dr. Catherine Mbidde emphasized the transformative potential of digital tools in shaping future opportunities. She, however, expressed concern over the growing trend of digital tool misuse – platforms that could otherwise be harnessed to explore career paths and unlock job prospects.
Dr. Mbidde urged the students to invest in nurturing their entrepreneurial skills, encouraging them to proactively develop plans, engage in regular self-assessment, and seek out mentors who can offer guidance and support along their professional journeys. She underscored the importance of spiritual grounding, advising students to cultivate a strong relationship with God as a source of direction and resilience in navigating the complexities of their career paths.
Mr. Basiima Collins from UniPod emphasized the importance of a mind-set shift as graduates navigate their career paths. He urged students to actively participate in networking events and foster an entrepreneurial mind-set, stressing that these actions are essential for personal and professional growth. “By embracing opportunities for networking, you can build valuable connections and open doors to new possibilities. Additionally, cultivating an entrepreneurial mind-set allows you to approach challenges with creativity, resilience, and a proactive attitude, which are crucial qualities for success in today’s dynamic job market.”
Addressing students on the significance of mental health in the journey of career development, Dr. Alex Behakanira emphasized the need to remain open-minded and adaptable. He noted that although job opportunities may appear scarce, the broader landscape of opportunities remains vast and ever-evolving. Dr. Behakanira encouraged students to strive for relevance not only in their professional environments but also within their homes and communities, underlining the importance of being well-rounded individuals. Echoing this sentiment, Mr. Henry Nsubuga stressed the importance of safeguarding one’s mental well-being throughout their career path. He advised students to cultivate a resilient mind-set and to be intentional about steering clear of situations that may lead to emotional distress or depression.
In his remarks, Prof. Juma Kasozi, the Deputy Principal of the College of Natural Sciences (CoNAS) and Head of Academics, expressed his appreciation for the initiative. He commended the effort as a timely and strategic intervention aimed at equipping students with the practical knowledge and emotional resilience necessary to navigate the dynamic and often challenging world of work. Prof. Kasozi emphasized that such initiatives play a crucial role in bridging the gap between academic theory and real-world application. He extended sincere gratitude to the seminar coordinators, praising their foresight and dedication in conceptualizing and organizing the programme.
The Terminal Seminar will be held on an annual basis.
By Dr. Alice Nabatanzi
Due to the frequent use of antibiotics for prophylaxis and treatment of poultry by Ugandan farmers, antibiotic resistance is on the rise. This has resulted in an outbreak of poultry and human diseases in addition to drug residues in chicken meat being consumed by the majority of Ugandans. Thus, “If you are eating chicken daily then you could be at a high risk.” These residues have spilled into the environment and also contaminated the food for the indigenous free-range chicken which people thought were safer to eat. Interestingly, some consumers think cooking chicken can reduce antibiotic residue levels, but it does not completely remove them. Boiling or frying chicken can cause antibiotic residues to migrate into the cooking liquid, but they don’t guarantee full degradation or elimination.
Looking at the situation at hand, I went back to our indigenous knowledge systems in a quest to formulate an organic poultry feed since natural solutions have proven safer, effective, and sustainable. But remember, to break the cycle or solve any problem, we have to start from the roots and this is by improving the diet for our poultry and ruling out the use of conventional antibiotics. Thus, I went ahead to investigate natural bacteriocins and phytobiotics which I integrated into a special feed for chicken. In addition to the feed is a probiotic solution for gut health.
Special thanks to the Government of Uganda through the Makerere University Research and Innovations Fund (Mak-RIF) for funding this research to prototypes.
Soon we will commence bulk processing and take the feed to the market but before that, we will scientifically validate the feed through efficiency testing in comparison with imported feeds and Uganda-produced feeds. Furthermore, we will produce different feeds to meet the needs of the different types of chicken (broilers, layers, dual-purpose). This will put our product in a better place on the market and also be able to convince our customers with concrete scientific evidence. In addition, we want to change the mindsets of the majority of Ugandans, especially poultry farmers, and let them understand that Organic poultry farming is the best as it results in quality meat, quality eggs, quality fertilizer, and more returns/ profits.
In conclusion, we need to embrace our indigenous systems and remember that once we were healthier without cancer, strange disease conditions, and rampant fertility issues. This is majorly because we consumed clean food as opposed to now where our food is highly contaminated with drug residues.
Dr. Alice Nabatanzi is a Senior Lecturer in the College of Natural Sciences (CoNAS), Makerere University
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