Review on double haploid in rice plant (Oryza sativa L.)

Abstract

Rice (Oryza sativa L.) is an important and indigenous crop in India. Rice is a plant belonging to the family of grasses, Gramineae (Poaceae). It is a major food crop of the world and forms the staple diet of about half of the world's population. Rice is repeatedly mentioned in ancient Indian texts, including the Yajur Veda. The area under cultivation of rice in India is 45416 thousand hectare, Total production of Rice during 2020-21 is estimated at record 122.27 million tonnes. Two major Asian cultivated varieties of rice have been historically recognized as japonica and indica subspecies. Japonica rice is sticky and indica rice is non sticky. Obtaining high quality homozygous pure lines by classical breeding methods is very time consuming and labour intensive. Due to uncontrolled pollination, the results are hard to obtain through this method. In-vitro haploid production offers an excellent solution for development of high quality homozygous pure lines in lesser time. Indica rice is mainly cultivated in tropical and subtropical environments at lower latitudes or altitudes, whereas japonica rice is grown mainly in more temperate environments at higher latitudes or altitudes. Anther culture is easy in japonica rice, but its application in Indica rice is limited as it is difficult to breed through anther culture. Indica cultivars of rice showed low anther culturability (1.2% callus induction) whereas Japonica cultivars had 20-fold higher (28.1%) anther culturability.