Castor Hybrid Variety Ubol 90

Abstract

A hybrid breeding program for castor has been carried out since 1981. Female plants (pistillate line - A1) were developed from the hybrid H78 introduced from South Africa. A1 has a short plant height, is green in colour, and has waxy coating on stem friut and vein (undernath the leaf), is spiny fruit and has a complex overley pattern on seed. It was crossed with male parents such as Lynn dwarf, Aruna, Baker tall type and LAC-38. f1 hybrids from their crosses were tested for yielding ability and other agronomic characters in perliminary trial. some promusing hybrids were tested further in standard, regional and fram trials including farm test with H 22, a hybrid from Israel, used as a standard check 91983 - 1989). Ubol 90, a bybrid between A1 and baker tall type, gave the average yield 199 kg2rai which was 10% higher than JH 22, Ubol 90 has a short plant height, red collour, waxy coating on stem, fruit and spike and smaller seed than H 22. The oil content of Ubol 90 was higher than H 22.