Registration of ‘CLL17’ rice

Abstract

‘CLL17’ (Reg. no. CV-160; PI 693941), a high-yielding long-grain rice (Oryza sativa L.) cultivar, was developed by the Louisiana State University Agricultural Center at the H. Rouse Caffey Rice Research Station near Crowley, LA, and approved for release in 2020. CLL17 contains the herbicide-resistant gene for use in the Clearfield rice production system. The Clearfield rice production system is defined as the brand of rice cultivars that are tolerant to imidazolinone herbicides. CLL17 was derived from the cross ‘CL131’/‘Trenasse’. It showed good yield potential and favorable agronomic characteristics in the 2015 Clearfield Preliminary Yield Trial. In 2016, it was evaluated in the uniform regional rice nursery trial across four southern states. From 2017 to 2022, CLL17 was evaluated in 50 replicated trials across 10 locations in Louisiana. Three high-yielding commercial cultivars were included as checks: ‘Cheniere’, ‘CL153’, and ‘CL111’. The grain yield of CLL17 was 9.0 t ha⁻¹ compared with 8.9 t ha⁻¹ for CL153, 8.3 t ha⁻¹ for CL111, and 8.2 t ha⁻¹ for Cheniere across 25 commercial advanced trials from 2017 to 2020. CLL17 had a similar plant height to CL111, 2-cm taller than CL153, and 5-cm taller than Cheniere. It exhibits typical US long-grain rice cooking quality with intermediate amylose and gel temperature. CLL17 is susceptible to sheath blight [caused by Rhizoctonia solani Kuhn ], resistant to Cercospora spp., leaf blast [caused by Magnaporthe grisea (T.T. Hebert)], and neck blast, and moderately susceptible to bacterial panicle blight (caused by Burkholderia glumae).