著者
Noriyuki Kuya Jian Sun Ken Iijima Ramaiah Venuprasad Toshio Yamamoto
出版者
日本育種学会
雑誌
Breeding Science (ISSN:13447610)
巻号頁・発行日
pp.19003, (Released:2019-10-04)
被引用文献数
10

Direct seeding saves time and labour in the cultivation of rice. However, seedling establishment is often unstable, and yields are lower than in transplanting. Anaerobic germination (AG) is a key trait for improvement of direct seeding of rice. We established a simple and reliable method of evaluating AG in rice breeding. We germinated seeds in distilled water or deoxygenated water and measured coleoptile length several days later; compared the results of each method with survival rate in flooded soil; and used the anoxic water method for QTL analysis and for testing cultivars. Coleoptile elongation in anoxic water and survival rate in flooded soil were significantly correlated (r = 0.879, P < 0.01). A significant QTL, likely to be a major gene (AG1), was found in chromosome segment substitution lines and in a backcrossed F2 population derived from tolerant and sensitive lines. Diverse rice genetic resources were classified into tolerant or sensitive accession groups reflecting their ecotypes. Our study revealed that anoxic water evaluation method saves space and time in a stable environment compared with flooded soil evaluation. It is applicable to QTL analysis and isolation of genes underlying anaerobic germination.
著者
Mouritala Sikirou Kazuki Saito Enoch G. Achigan-Dako Khady Nani Dramé Adam Ahanchédé Ramaiah Venuprasad
出版者
日本作物学会
雑誌
Plant Production Science (ISSN:1343943X)
巻号頁・発行日
vol.18, no.4, pp.423-434, 2015 (Released:2015-09-19)
参考文献数
89
被引用文献数
39

In sub-Saharan Africa, the demand for higher rice production continues to grow rapidly. Although there is a huge potential for increasing rice production through expansion of the rice cultivation area in wetlands, iron (Fe) toxicity tends to occur and consequently results in low rice yield. Development and deployment of varieties tolerant to Fe toxicity is one of the practical options to overcome this constraint. Several tolerant varieties have been developed through conventional breeding but progress in breeding has been generally slow mainly due to large genotype × environment interaction and field heterogeneity, which make rice selection ineffective. In addition, there are no valid managed-stress screening protocols which are highly efficient and that can predict rice performance in the diverse target environments of West Africa. Many O. glaberrima accessions have superior tolerance, but only a few of them have been utilized in breeding programs. The known quantitative trait loci (QTLs) related to Fe toxicity, have not been used for marker-assisted selection (MAS), as they gave small effects with a large confidence interval. Accelerating rice breeding efficiency for tolerance to Fe toxicity requires establishment of reliable screening protocols, use of O. glaberrima accessions as donors, identification of large-effect QTLs and MAS using such QTLs. This paper reviews the past and current efforts in West Africa to develop new varieties with superior tolerance to Fe toxicity.