Investigation of Physiological Indices of Different Rice ( Oryza sativa L.) Varieties in Relation to Source and Sink Limitation

摘要

An experiment was conducted at Iran Rice Research Institute-Deputy of Mazandaran (Amol) in 2007, to study the physiological and morphological indices of different rice varieties. The experiment was carried out with, Factorial experiment in randomized completely block design comprising four replications. Studied factors were limitation of source and sink in 4 treatments viz., (1) cut all of leaves except flag leaf, (2) cut flag leaves, (3) cut 1/3 end of panicle and (4) control. Variety in four treatment was as Tarom, Neda, Shafagh and Fajr. Completion of source and sink limitation treatments were carried out at 50% flowering stage. Results showed that the most CGR was related to Shafagh variety (25.18 g/m²/day) in 1650 GDD and the least CGR was produced in the Tarom variety (21.1 g/m²/day) in 1452 GDD. The most RGR was obtained in the Shafagh and the least RGR was obtained in the Neda variety at the 850 GDD. Completion source and sink limitation treatments on leaf area index showed that cut all leaves except flag leaves had least leaf area index also with cut all of leaves and flag leaves in all of varieties the RGR was decreased. Results of morphological characteristics measurement showed that highest plant height and least plant height were produced in the Tarom and Shafag varieties, respectively. Maximum leaves number in the Tarom variety was produced in the 1180 GDD. Also, the Neda variety with produced 24 tillers per plant had most tiller number. The Tarom variety with coefficient 81.25% had most conversion all tillers to fertile tiller percentage.