Plant breeders of the Philippine Rice Research Institute (PhilRice) have bred promising hybrid lines with outstanding yield performance and resistance to bacterial leaf blight (BLB).
Joanne D. Caguiat, PhilRice hybrid project leader, said most of the previously released hybrid varieties lack sufficient resistance to BLB, one of the common rice plant diseases that can cause yield loss of 70%.
The first hybrid line, PR4064OH, is an improved version of the Mestiso 3 (M3) with Xa21, a gene that exhibits resistance to BLB. Based on the evaluation, this hybrid is more resistant to most BLB isolates in the country compared with M3.
The other hybrid line, PR47216H, has an average yield of 9.6 tons per hectare which is 22.24% and 31.06% higher compared with Mestiso 19 and PSB Rc82, respectively.
PR40640H will soon be submitted to the National Cooperative Test (NCT), while PR47216H is currently being tested for multi-location trials. NCT evaluates rice lines in terms of yield, pest and disease resistance, and grain quality across locations.
As soon as these lines pass the NCT, they will be recommended for registration at the National Seed Industry Council which approves the release of rice varieties.
According to Caguiat, hybrid rice varieties are not developed in a snap. “Their development starts with careful selection and testing of genetically diverse inbred lines, making crosses, and choosing the best hybrid combinations through years of testing for field performance, disease and insect resistance, and grain quality,” she elaborated. (PhilRice Press Release).