Agro-morphological characterization of ovary culture-derived plants of rice (Oryza sativa L.)

Plants derived from unpollinated ovary culture of ten rice genotypes showed significant variability in agro-morphological characteristics. The ovary-d erived plant (H-1) populations were completely haploid, doubled haploid or haploid-doubled haploid mixture. Haploids had very drastic reduction in pla nt height, panicle length, grain length, breadth and number and spikelet fe rtility (0.0%-2.1%). Doubled haploids from the hybrid of UPRI 95-121 x UPRI 95-165 were normal with fertility ranging between 69.6% and 97.7%. A genet ic segregation in ratio of 1:1 was observed for five pigmentation character s in the H-1 population derived from hybrid UPRI 95-122 x UPRI 95-165. Plan t height showed the largest coefficient of variability (28.5%) followed by the number of spikelets per panicle (24.2%), number of grains per panicle ( 22.0%), percent seed set (9.2%) and panicle length (9.0%). The range of var iation in the H-1 population from fully fertile hybrid PMS 2A (CMS) x IR 31 802 (restorer) was similar to its corresponding F-2 population for plant he ight, spikelet fertility and number of grains/panicle. A single clone of pl ants from the cultivar BG 1321 exhibited complete male sterility but normal female fertility when pollinated with other varieties. Ovary-derived plant s from the CMS lines PMS 2A and IR 58025A showed stable male sterility and those from thermosensitive genetic male sterile line UPRI 95-140 showed the rmosensitive genetic male sterility. These Lines have potential in the hybr id breeding program and are being currently exploited.