His Innovation To Graft A Poisonous Weed With An Edible Fruit Won Him An International Science Award.

Stephen Ng'ang'a Wainaina showing the length taproot of a young bug weed . The weed was propagated with tree tomato to develop a resistant species of the fruit.

When you meet him in the streets, he looks just like any other ordinary fellow in town but Alas! You are so mistaken. This man is just too valuable to this country and to the world at large especially in the field of innovations and organic farming.

His name is Stephen Ng’ang’a Wainaina, the 2014 Winner of the Organic Farming Innovation Award (OFIA) at an awards ceremony held in Istanbul, Turkey on the 14^th of October.

Wainaina, who is the Executive Director of Organic Agriculture Centre of Kenya (OACK), was crowned the Science Prize Winner for his Tamarillo or Solanum betaceum (popularly known as the tree tomato) grafting technology, an innovation that enhances resistance to fruit diseases, pests and drought.

IFOAM - Organics International is an international umbrella organisation of the organic world with 800 affiliates in more than 100 countries that unites an enormous diversity of stakeholders contributing to the organic vision. Every three years, at the Organic World Congress (OWC), IFOAM-Organics International, the Rural Development Administration (RDA) of Republic of Korea and the IFOAM Technology Innovation Platform (TIPI) award great organic innovators with the Organic Farming Innovation Award (OFIA).

OFIA is an initiative of the government of the Republic of Korea in remembrance of the 17th Organic World Congress (OWC) 2011 held in its Gyeonggi Province. OFIA is awarded in two categories: the Grand Prize and the Science Prize.

In the year 1982, when Wainaina was studying an advanced Agriculture course at the Murrumbidgee College of Agriculture, New South Wales Australia, he came across the Bug weed variously known as wild tobacco or Solanum mauritianum (indigenous Muthakwa plant) growing among other weeds.

A year later, he found the same weed growing in his rural home in Murang’a County. At the time, he was growing ungrafted tree tomatoes on his farm, which were by then withering and drying up due to the dry weather conditions. He realised that the bug weed was still green and showed no effects of the dry weather. It is from this observation that Wainaina got interested in understanding the reason why the two plants behaved differently.

After doing his analysis, he discovered that the bug weed survived the drought due to its deep rooting.

“I realised that my tree tomato plants had shallow root system, thus the reason they were unable to withstand the dry weather for a long period. I took a sample of the bug weed to Kabete University for some genetic and taxonomic analysis where I discovered that it belonged to the same family with the tree tomato,” explained Wainaina.

When he came back to his farm, Wainaina experimented by propagating the bug weed with his tree tomatoes just in case it developed a better species that would withstand the drought. The two became compatible and grew well without any problem. They both belong to Solanaceae family, hence compatibility.

“The grafted tree tomato never withered or showed signs of being overcome by the dry weather. They developed some vigour, were able to grow faster before the pests and diseases accumulated and even before the water became scarce. This way they were able to evade pest and disease destruction and water shortage hence ended up giving me a higher yield. Additionally, the mixture of genes enabled functions such as photosynthesis to work better. When this happened, my hybrid plants produced bigger fruits compared to the ungrafted ones,” he said.

The ordinary tree tomato plants which usually have shallow root system, were bettered through grafting. The bug weed-grafted variety did not require a lot of water because its deep rooted taproot allowed them to get nutrients and water underground.

Poisonous Plant.

The bug weed is an invasive weed and some people have declared it poisonous to both human beings and animals. It has been for a long time regarded as uneconomic weed to be eliminated, even included in the Global Invasive Database (GIS D. 2006) because it serves no economic purpose and is regarded to pose characteristics harmful to humans and environment.

Wainaina showing a mature bug weed that has grown wildly in a tree tomato farm.

The bug weed is resistant to diseases and drought. It shows a healthy growth in the wild, where it is found.

All these statistics did not put off Wainaina and he went ahead to propagate it with his tree tomatoes.

“Before my retirement from the University of Nairobi as a plant propagator, I had gained a great wealth of experience in that field. Over 32 years’ experience to be precise. I knew that the fruits would not sap any poison from the weed as they originate from the scion and the poisonous part of the plant originate from the bug weed. Therefore, the poison cannot be transferred to the scion which is now the tree tomato,” he explained.

In this way, the bug weed was robbed of all its powers to harm the tree tomato. Once grafted with the tree-tomato, the result was a crop with a promise as the grafted tree tomato seedling improved its capability to resist disease and drought.

The tree tomato, being shallow rooted, profited from the deep tap root and the many strong auxiliary roots of the bug weed. Grafting these two plants improved the stem and root system, as the grafted fruit plant has a stronger anchoring. Long term resistance to fruit diseases, pests and drought are the other gains that were developed from this innovation.

The grafted plants bear improved fruits, can be used for own consumption or sold for fruit consumption and for making fresh juices to earn extra money. Improved tree tomato has further potentials to ensure food security and generate income.

Tree tomato is an important source of vitamins A and C that are lacking in many African diets. Low intake of vitamins by around 50 million African children is considered to be the third biggest public health problem in Africa after HIV/AIDS and Malaria.

It also provides fodder for livestock.

Nowadays, there has emerged a high demand among farmers for the grafted tree tomato seedlings as the quality fruits are attracting higher prices. There is also the need to sensitise consumers about benefits of eating the fruits.

Wainaina holds a Post Graduate Diploma in Horticulture from University of Greenwich England, and has attended an Advanced Agriculture Course at Murrumbidgee College of Agriculture, New South Wales, Australia.

  

You can reach Wainaina through contact:  

Stephen Ng’ang’a Wainaina, OACK, P.O BOX 69-10218, Kangari, Kenya

E-mail: stephenoack@gmail.com 

Web: www.oack.or.ke