Dry matter production and partitioning in different plant parts of rice cultivars under irrigation regimes and systems of cultivation

Growth and yield characteristics of genotypes depend on genetic and environmental factors. Among the different production factors, varietal selection at any location plays an important role. Proper crop management depends on the growth characteristics of various varieties to get maximum benefit from new genetic material. Among the different water-saving irrigation methods in rice, the most widely adopted is alternate wetting and drying (AWD). Many of the rice cultivars vary in their performance under different systems of cultivation. A field experiment was conducted on a clay loam soil at Indian Institute of Rice Research (IIRR) Rajendranagar, Hyderabad, Telangana during the kharif seasons of 2017 and 2018. to study the “productivity and water use efficiency of rice cultivars under different irrigation regimes and systems of cultivation” The treatments consisted of two irrigation regimes Alternate wetting and drying and Saturation as main plot treatments, three establishment methods System of Rice Intensification (SRI), Drum Seeding (DS) and Normal transplanting (NTP) as sub plot treatments and four Cultivars namely DRR Dhan 42, DRR Dhan 43, MTU-1010 and NLR-34449 as sub-sub plot treatments summing up to 24 treatment combinations laid out in split-split plot design with three replications. At 60, 90 DAS/DAT and harvest significantly dry matter production (DMP) was recorded with DRR Dhan 43 cultivar (607, 4320 and 11548 kg ha⁻¹ respectively in pooled means of both 2017 and 2018) than other cultivars. Whereas MTU-1010 and NLR-34449 recorded on par dry matter production values at all the crop growth stages during both the years of study. However, DRR Dhan 42 produced the lowest dry matter production compared to other genotypes. DRR Dhan 43 recorded higher dry matter accumulation (g m²) in root, stem and leaves at all the crop growth stages, during both the years of the study over other cultivars. Alternative wetting and drying method of irrigation recorded significantly higher DMP at all the growth stages of rice (60, 90 DAS/DAT and at harvest) except at 30 DAS/DAT during both 2017 and 2018 as compared to saturation. SRI recorded significantly higher DMP as compared to normal transplanting; however, it was comparably at par with drum seeding at all the growth stages.