Effect of transplanting date and age of seedlings on growth, yield and quality of hybrids under system of rice (Oryza sativa) intensification and their effect on soil fertility

A field experiment to study the effect of transplanting date and age of seedlings on growth, yield and quality of rice hybrids under SRI and their effect on soil fertility was conducted on sandy-clay loam soil at Varanasi during rainy (kharif) seasons of 2012 and 2013. The experiment on sandy loam soil was laid out in split-split plot design assigning three dates of transplanting (27 June, 7 July and 17 July) in main plot, two rice hybrids (PHB-71 and Pusa RH-10) in sub-plot and three age of seedlings (10, 14 and 18-day old) in sub-sub plot with three replications. Results revealed that higher growth parameters, viz. plant height (104.2 cm), tillers/hill (20.4), leaf area index (5.16) and dry matter accumulation/hill (31.2 g) and yield attributes, viz. effective tillers/m2 (248.2), panicle length (30.5 cm), grains/ panicle (176), weight/panicle (5.08 g) and test weight (23.11 g), grain and straw yield (6.67 and 8.71 tonnes/ha, respectively) and harvest index (43.17) were observed under 27 June transplanting as compared to rest of the two dates of planting. Protein content in grain and kernel length before and after cooking also registered significant improvement in 27 June transplanted crop. The magnitude of increase in grain and straw yield of hybrid under SRI by the early transplanting (27 June) as compared to the late transplanting (17 July) was 19.9 and 15.2 %, respectively on pooled basis. However, soil pH, EC, organic carbon, available NPK, hulling, milling and head rice recovery percentage, kernel breadth (B) before and after cooking, length (L) elongation ratio and L/B ratio remained unaffected due to different dates of transplanting. Among the hybrids, PHB-71 produced markedly higher plant height (104.8 cm), tillers/hill (17.6), leaf-area index (4.91), dry matter accumulation/hill (29.5 g), effective tillers/m2 (236.4), panicle length (30.1 cm), grains/panicle (188), weight/panicle (4.62 g), test weight (22.67 g), grain yield (7.00 tonnes/ha), straw yield (8.95 tonnes/ha) and harvest index (43.87) over Pusa RH-10. Organic carbon content in soil as well as quality parameters viz. hulling, milling and head rice recovery percentage, protein content and kernel breadth before and after cooking were also recorded higher with PHB-71 than the Pusa RH-10. However, maximum available NPK, kernel length before and after cooking, length elongation and length breadth ratio before cooking were recorded with ‘Pusa RH-10’. Younger aged seedlings (10-day old) r