Sakha108 Egyptian Rice Variety Japonica Type High Yielding and Resistant to Blast

Abstract

Sakha108 was released in 2018 as a high yielding cultivar amended for enhancing rice production in Egypt. Sakha108 was developed from backcrossing between Sakha101 and HR5824-B-3-2-3 to retrieve blast resistance that was broken in wide spread variety Sakha101. The cross between Sakha101 and HR5824-B-3-2-3 was initiated in 2003, F1 then was backcrossed with Sakha101 as to produce F1BC1. This backcross was advanced up to 2008 to enrich the genetic background of the recurrent parent Sakha101 along with blast resistance and reach homozygosity up to F1BC6. Five selected promising sister lines were evaluated in preliminary yield trial (GZ8564-SP70-20-6-1-1, GZ8564-SP70-20-6-1-2, GZ8564-SP70-2-6-1-3, GZ8564-SP70-20-6-1-4 and GZ8564-SP70-20-6-1-5). The promising line GZ8564-SP70-20-6-1-1 surpassed all selected lines and was evaluated from 2010 to 2015 in multi-location yield trials, regional, final and verification yield trials. The results indicated that GZ8564-SP70-2-6-1-1 exceeded yield potential of recurrent parent Sakha101, yet with shorter growth duration and blast resistance. The selected line grain yield recorded 10.75 and 11.00 t/haduring 2015 and 2016 seasons with total duration 137 day, while Sakha101 recorded 10.32 and 10.50 t/ha, respectively with a total growth duration of 145 day. GZ8564-SP70-2-6-1-1 showed high level of blast resistance in the field and artificial inoculation under greenhouse conditions compared with Sakha101 that showed susceptible reaction to rice blast under both field and greenhouse conditions. The application of 165 kg N/ha-1 and wider space (25x20 cm) significantly increased growth, yield attributes and grain yield of the new cultivar Sakha108. The new cultivar exhibited multiple resistance to other important biotic stresses.