I am solving age-old problems in horticulture with new ways of thinking

Occasionally, in Kenya, there is a season of disruptive tomato shortage. It strikes, a biting scarcity persists for months, and the tomato becomes a major import commodity from neighbouring countries.

It indeed becomes a premium item on many shopping lists, and Kenyans who can't afford it even stop using it in their cooking as prices skyrocket. 

Kenyan scientist, Annah Indeche, has been watching this annual event with clenched teeth. 

Dr. Indeche, a lecturer at the Jomo Kenyatta University of Agriculture and Technology (JKUAT) horticulture and food security department, first took note of how big a problem the blossom end rot (BER) was, during farm visits and interaction with farmers on vibrant Farmers' groups (African Farmers Club and Digital Farmers) on Facebook. 

Blossom-end rot (BER) is a physiological disorder that causes a dark, sunken area on the lower (blossom) end of the tomato, pepper, and eggplant fruits. 

"It bothered me quite a bit. But I knew it was within my purview to do something about it, and that is how I decided that amongst all the other things that I was doing I would dedicate my research to addressing this tomato problem," she says.

She says she decided to focus her project on understanding the tomato rot, because a lot was already being done on pests and diseases while their physiological disorders were being ignored, yet they were also responsible for lowering yield and quality. 

Results of a study Dr. Indeche did among tomato farmers in Kenya in 2018 showed that "BER" is one of the most important physiological disorders in tomatoes. 

"So I decided to look into that aspect of tomato production and was very fortunate in 2016 to get a scholarship courtesy of Africa-ai-Japan project, a Japan International Cooperation Agency (JICA) initiative, to go to Okayama University in Japan to study for my Ph.D. in Agriculture focusing my project on the tomato," she added, when I caught up with her at a trial site for tomato plants in JKUAT. 

In a greenhouse at the university, she is growing tomatoes under different root volume restriction systems to test out how the rot can be managed.

"My research is focused on understanding the development of BER," she explained, "It is associated with calcium deficiency in the fruits and is characterised by the appearance of a dead black patch on the fruits, observed at the end of the fruit that is not attached to the stem, leading to diminished yield and quality." 

In the greenhouse and back in the lab she curiously studies calcium transport into fruit and deficiency symptoms. 

As Dr. Indeche explains, her Ph.D. work was on determining the effect of stripping of leaves on the tomatoes due to BER incidences and calcium transport into the fruits as influenced by environmental factors under moderate water stress. She is building on the research currently.

With her experiment, she measures carefully the amount of nutrient solution that goes into each plant. "Every drop of water that goes into the roots is calculated," she notes. 

In Japan, using Japanese tomato varieties, she found a technique that can be used to manage tomato rot especially in large fruit cultivars (tomatoes that are produced and maintained by horticulturists but do not produce true-to-seed), which are more susceptible to the condition. 

"I'm trying to see which root volume restriction (by growing the tomatoes in different size small pots and using sensor technology for irrigation in the greenhouse), will produce a better quality of tomato. 

While doing my Ph.D. research in Japan the results showed that stripping the leaves significantly reduced tomato rot in all experiments under this root restriction system.

"With resources from JICA, I'm trying to replicate it here to see if we can get similar results with our different varieties so that I can give a practical recommendation to farmers," she explains. 

"This experiment is very relevant to Kenya because BER is one of the physiological disorders that greatly reduce yield and quality of tomatoes thus affecting both farmers in terms of reduced income and consumers in terms of reduced quality. I just hope that I can provide in a small way a solution to the huge problem the tomato farmers are facing especially those growing tomatoes under greenhouse conditions," she adds. 

Dr. Indeche is not using the normal soil in her experiments to avoid soil-borne diseases. "I am using peat moss that is readily available locally. Cocopeat too can be used. It is not expensive. For nutrients, I am using soluble fertilizers under a hydroponic system to feed my tomatoes. These fertilisers are also not very expensive and under the system, we have developed, there is efficiency in supply because irrigation occurs only when the plants need the solution," she says. 

She says the blanket application of nutrients, by most farmers leads to wastage and pushes up the costs. 

"I am evaluating this system to see whether it makes economic sense before I can be able to make a sound recommendation to the farmers," the lecturer notes. 

But her determination to find solutions to some of Africa's food production problems does not stop with the tomato. 

She hopes this experiment can enrich the current knowledge on the mechanisms of development of physiological disorders associated with Calcium nutrition and environmental conditions on all fruits.

"Improving our agricultural technologies will enhance food and nutrition security and increase incomes," she says, "that is what gets me out of bed every morning." 

Beyond the tomato project, Dr. Indeche says she has done other related research like assessing the factors influencing farmers' application of sustainable agricultural practices in rice farming in Kenya and the readiness of indigenous vegetables women farmers to satisfy quality standards of high-value markets in Kenya.

"I share with my students at the university to enrich their aspiration for evidence-based knowledge," says the lecturer who has been in the department of horticulture actively involved in assisting students for the last 24 years. "Teaching is also about setting the pace, stimulating and arousing the students' desire for problem-solving. I hope what I'm doing filters through to them." 

Dr. Indeche is currently writing a book titled "Field handbook on physiological disorders of horticultural crops" that will assist in the correct diagnosis of physiological disorders. 

"It will appeal to farmers, students, researchers, and teachers. It can also be used as extension training material by agricultural officers in Africa," she says. 

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