Breeding rice for salinity tolerance and salt-affected soils in Africa: A review

Soil salinity is one of the most severe and common abiotic stresses affecting Africa’s rice productivity. To better present the current state and help future scientists better understand the challenges and focus their efforts toward developing salt-tolerant rice varieties, this study provides an overview of the various approaches, that can be employed to attain salt stress tolerance in rice.

Agriculture is the backbone of the African economy, which accounts for one-third of the Sub-Saharan African countries’ gross domestic product, employing about 65-70% of the African workforce.

However, the region lags behind others worldwide regarding agricultural productivity. This is due to several reasons that apply at different levels of the food value chain, making Africa a food-insecure continent.

A core problem with soils in Africa is degradation caused by escalating salinization, accelerated soil erosion, acidification, plant nutrient depletion, and soil biodiversity loss.

In most of the sub-Saharan African countries, land and soil degradation undermines efforts toward sustainable agricultural production and poses a major threat to the future of agriculture.

Soil salinity, among the causes of agricultural land degradation in Africa, is one of the most severe and common abiotic stresses affecting rice productivity.

There are several approaches for the management of salt-affected soils. However, one of the best approaches to overcoming salt stress problems in Africa could be through breeding crops with stress-tolerant genes so that they can be grown in salt-prone areas. Salt tolerance rice genotypes have been identified using conventional breeding and modern biotechnology approaches.

Furthermore, quantitative trait loci (QTLs) associated with salt stress tolerance have been mapped on different regions of the rice genome. The identified genes and genotypes are the potential donors in the development of new tolerant rice cultivars adapted to local environments.

Conventional breeding has been a successful method; however, the approach has been time-consuming as it requires many years to develop a new variety.

Biotechnology approaches are more advantageous, offer an improved alternative for transferring salt tolerance genes, and provide a rapid way to develop new tolerant rice cultivars that could help reduce the consequences caused by soil salinity effects in Africa.

Using modern breeding methods, the development of salt-tolerant rice varieties is guaranteed and ensures increased and sustainable agricultural productivity.