**9. Challenges of hybrid rice adoption**

Like other continents, Africa will have to overcome the major constraints to large scale adoption of hybrid rice. These include high cost of seeds, poor grain quality issues, pest and diseases susceptibility, human capacity for hybrid rice development and the difficulty of identifying higher heterosis (> 25%) at the field level [30]. Most African rice farmers have built a tradition of using self -saved seeds. This tradition, maybe, was to adapt to the unavailability of adequate reliable seed companies to ensure timely supply of quality rice seeds. Most rice farmers still use traditional varieties. For the few that use improved varieties, it is through the informal system. The business of rice seed production is at the budding stage and will have to be developed before hybrid varieties could have a place. Most African governments still ensures that their farmers get the benefits of improved seeds through the subsidy. The major challenge for hybrid rice includes whether African rice farmers will be willing to buy hybrid seeds for every cropping season and to do so at a higher price. The hybrid rice technology itself could also act as a catalyst to creating a sustainable rice seed business by providing varieties with high yield advantage which can attract farmers to patronize improved rice varieties. That means the realizable yield advantage of hybrids on the field should be high enough. Although initial studies suggest that farmers anticipate above 30% yield advantage over existing best inbred to guarantee adopting a variety that requires seasonal seed purchase [27], there is a technical limitation to the realizable field heterosis by hybrid varieties.

Sub-Saharan Africa is among the few places globally where rice yields are still low with average yield of about 2.2 t/ha. This is largely due to the use of less productive cultivation technologies and inputs particularly fertilize [31]. Although hybrid

varieties perform relatively better under stress conditions, the full potential could be realized under optimal inputs. For African rice farmers to realize the yield benefit of hybrids, there will be the need for hybrid seeds be accompanied with a well-researched and recommended agronomic package that will give farmers the best yield.

Hybrid rice is new to the African continent and knowledge on the technology is limited. There will be the need to train a critical mass of scientists and technicians on hybrid rice research and seed production to spearhead the development, demonstration and adoption of the technology. Aside that, farmers should be educated not to save and replant hybrid seeds.

The African continent is fragmented in terms of essential traits. There will be the need to develop different hybrid combinations for different rice production regions depending on their important traits. Hybrid rice breeding uses concepts, skills, and procedures which are strikingly different from those used for conventional inbred rice development. Unlike conventional inbred rice development which accumulates productive genes that perform well in a homozygous state year after year, hybrid rice breeding exploits hybrid vigor which provides additional genes that add to the yield obtained by the productive genes in the homozygous varieties. Most introduced rice hybrids tend to have problem of susceptibility to local pest and diseases such as blast, rice yellow mottled virus (RYMV) disease and African rice gall midge (AfRGM) [25]. Aside these stresses, poor grain quality was one of the major constraints for large scale adoption of hybrid rice in Asia. Varieties with long slender aromatic grains that cook soft are mostly preferred by consumers within the West African sub-region. Breeders will have to battle with these traits which are mostly quantitatively inherited and difficult to combine in in developing products.

#### **10. Conclusion**

There is an emerging interest to position hybrid rice as a technology that can contribute to attaining rice self-sufficiency in Africa. Some African countries have responded by testing promising introduced and in-house hybrids developed by the pan-African rice research institute (AfricaRice). Some of these hybrids have shown favorable yield advantages over the best available inbred lines, but there are reports of susceptibility to some local pest and diseases. Initial studies on seed production potential indicates that most countries have conducive environment for local hybrid rice seed production. Nonetheless, there is the need to train a critical mass of scientists and technicians to champion the hybrid rice agenda and educate farmers not to save and re-plant hybrid rice seeds. There are a number of traits that hybrid breeders should also consider in developing products for the various market segments. For farmers to appreciate the need for buying seeds every season and at a higher price, hybrid varieties with higher field level heterosis should be developed and demonstrated. Also, promotion of hybrid rice seeds should go along with a well-researched recommended crop management package that will give farmers the best of yield. The hybrid rice agenda should form part of the overall strategy to develop a sustainable integrated rice seed sector to benefit African rice farmers.

#### **Acknowledgements**

This chapter is part of the review of a PhD thesis research funded by Alliance for a Green Revolution in Africa (AGRA) through the West Africa Centre for Crop Improvement (WACCI), University of Ghana. The advice and suggestions of my supervisors are greatly acknowledged.

**57**

**Author details**

Samuel Oppong Abebrese\* and Alex Yeboah

provided the original work is properly cited.

CSIR-Savanna Agricultural Research Institute, Tamale, Ghana

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: sam555oppa@yahoo.com

*Hybrid Rice in Africa: Progress, Prospects, and Challenges*

*DOI: http://dx.doi.org/10.5772/intechopen.93801*

*Hybrid Rice in Africa: Progress, Prospects, and Challenges DOI: http://dx.doi.org/10.5772/intechopen.93801*

*Recent Advances in Rice Research*

to save and replant hybrid seeds.

**10. Conclusion**

varieties perform relatively better under stress conditions, the full potential could be realized under optimal inputs. For African rice farmers to realize the yield benefit of hybrids, there will be the need for hybrid seeds be accompanied with a well-researched

Hybrid rice is new to the African continent and knowledge on the technology is limited. There will be the need to train a critical mass of scientists and technicians on hybrid rice research and seed production to spearhead the development, demonstration and adoption of the technology. Aside that, farmers should be educated not

The African continent is fragmented in terms of essential traits. There will be the need to develop different hybrid combinations for different rice production regions depending on their important traits. Hybrid rice breeding uses concepts, skills, and procedures which are strikingly different from those used for conventional inbred rice development. Unlike conventional inbred rice development which accumulates productive genes that perform well in a homozygous state year after year, hybrid rice breeding exploits hybrid vigor which provides additional genes that add to the yield obtained by the productive genes in the homozygous varieties. Most introduced rice hybrids tend to have problem of susceptibility to local pest and diseases such as blast, rice yellow mottled virus (RYMV) disease and African rice gall midge (AfRGM) [25]. Aside these stresses, poor grain quality was one of the major constraints for large scale adoption of hybrid rice in Asia. Varieties with long slender aromatic grains that cook soft are mostly preferred by consumers within the West African sub-region. Breeders will have to battle with these traits which are mostly quantitatively inherited and difficult to combine in in developing products.

There is an emerging interest to position hybrid rice as a technology that can contribute to attaining rice self-sufficiency in Africa. Some African countries have responded by testing promising introduced and in-house hybrids developed by the pan-African rice research institute (AfricaRice). Some of these hybrids have shown favorable yield advantages over the best available inbred lines, but there are reports of susceptibility to some local pest and diseases. Initial studies on seed production potential indicates that most countries have conducive environment for local hybrid rice seed production. Nonetheless, there is the need to train a critical mass of scientists and technicians to champion the hybrid rice agenda and educate farmers not to save and re-plant hybrid rice seeds. There are a number of traits that hybrid breeders should also consider in developing products for the various market segments. For farmers to appreciate the need for buying seeds every season and at a higher price, hybrid varieties with higher field level heterosis should be developed and demonstrated. Also, promotion of hybrid rice seeds should go along with a well-researched recommended crop management package that will give farmers the best of yield. The hybrid rice agenda should form part of the overall strategy to develop a sustainable integrated rice seed sector to benefit African rice farmers.

This chapter is part of the review of a PhD thesis research funded by Alliance for a Green Revolution in Africa (AGRA) through the West Africa Centre for Crop Improvement (WACCI), University of Ghana. The advice and suggestions of my

and recommended agronomic package that will give farmers the best yield.

**56**

**Acknowledgements**

supervisors are greatly acknowledged.
