London — A research study carried out in two semi-arid areas in Mozambique has found that watermelon is a good companion crop for intercropping with grain to mitigate the risk of total crop failure due to drought.
The findings, published in the academic journal "Experimental Agriculture", show that although the yield of each crop does fall, the overall productivity of the land increases by thirteen per cent.
Researchers from Mozambique and Denmark, led by Paulino Munisse of the Agriculture Research Institute of Mozambique, point out that intercropping is common practice in tropical developing countries, but state that most research has gone into intercropping with legumes, due to their ability to fix nitrogen into the soil.
Intercropping has the advantage of increasing canopy coverage, which reduces water loss and weeds. In addition, it provides a safety net in case of complete crop failure due to pests or disease affecting the main harvest.
In this study, the researchers looked at two villages in Mabalane district, in the southern province of Gaza (namely Mathize and Yimba Yimue B). The experiment took place on 33 farms between December 2009 and May 2010.
The study found that intercropping maize and watermelon has important implications for food and income security, because the drought tolerant watermelon yields even under extreme conditions where the cereal crop might fail.
The study does not look at whether profit rates would rise due to the intercropping, but pointed out that during the experiment farmer income was "supported by a group of women traders who transported part of the watermelons about 300 kilometres to a better price market in Maputo".
The research noted that although maize is not recommended for the specific agro-ecological conditions of this area, the crop is highly valued by local communities and is still a dominant crop in the area.
Taking this factor into account, the researchers found that "watermelon intercropping with maize does not seriously reduce the yield of the maize crop.
However, it reduces the risk of complete crop failure when only maize is cultivated in such drought prone areas. This is an example of farmers' ability to mitigate drought risk and ensure regular supply of food and income through the use of diversified cropping systems".
The research paper concluded that "strategies for agriculture adaptation to drought and extreme climate events are needed, as it is predicted that climate change will affect agriculture in many African countries, particularly in semi-arid areas.
Diversification of agriculture and promotion of locally adapted, drought tolerant crops is one strategy to mitigate the effect of this development".