Please use this identifier to cite or link to this item:
|Advisor:||Singh, K N|
|Title:||Growth and yield simulation studies of wheat (Triticum aestivum L. emend. Fiori & Paol) genotypes as influenced by sowing dates under temperate Kashmir|
|Agrotags:||Cropping sequence, Cultivar, Simulation, Sowing date, Wheat, Yield|
|Abstract:||The field experimentation was undertaken at Shalimar campus of S.K. University of Agricultural Sciences and Technology during 2003-04 and 2004-05 with the objectives to find optimum sowing date of wheat and suitable cultivar under lower belts of Kashmir valley and to simulate trends of wheat production. Experiment was laid in split plot design assigning sowing dates (1, 15 and 30 October) main plot and six cultivars of wheat (HS 240, HS 295, HS 365, SKW 191, SKW 193 and SKW 196) sub-plots. Genetic coefficients of six cultivars were generated for calibration and validation of model CERES-wheat Ver 4 (DSSAT4). Wheat sown on 1 October produced highest grain yield of 43.27 and 57.01 q ha-1 also during 2003-04 and 2004-05, respectively, over 15 October (38.78 and 52.08 q ha-1) and 30 October (35.94 and 44.12 q ha-1). Magnitude of superiority of 1 October sowing over 15 and 30 October was 10.38 and 16.94 per cent during 2003-04 and 8.65 and 22.61 per cent, respectively during 2004-05. Growth characters like dry matter, tillers m-2 and yield attributes like effective tillers and test weight were recorded highest with 1 October sowing. To complete growth phases more days were taken by early sowing and accumulated heat units were comparatively also more with the early sowing. Cultivar SKW 191 and HS 240 recorded highest grain yield and N, P, K uptake. The superiority of genotype SKW 191 over HS 295, HS 365, SKW 193 and Shalimar wheat-1 was 6.72, 20.56, 19.80 and 16.0 per cent, respectively during 2003-04 and corresponding values for 2004-05 were 3.27, 11.6, 7.65 and 4.65 per cent, respectively. Growth characters like LAI, dry matter and tillers, yield attributes, ear weight at maturity, number of grains ear-1, effective tillers were also recorded higher with these varieties (SKW 191 and HS 240). In cropping sequence rice was transplanted after harvest of wheat during both the years. However, gap between wheat harvest and transplanting of rice was only 2-3 days. Rice yield of 55 and 48 q ha-1 was recorded during 2003-04 and 2004-05, respectively. Simulation studies showed that existing cultivars of wheat can not be harvested before 20 June, except during those years when temperature is mainly higher than normal or sown during first week of September. To evaluate the performance of model as sensitivity analysis revealed that elevated carbon dioxide levels increased simulated wheat yield and increased temperature decreased simulated yield markedly. Simulation studies indicated that the most appropriate time for wheat sowing under existing agroclimatic conditions is between 20 to 30 September. Further nitrogen dose of 200 kg ha-1 at 1 October sowing recorded highest simulated grain yield but difference between 100 and 200 kg nitrogen was marginal. At each sowing date, increasing level of nitrogen increased grain yield. It can be concluded that optimum sowing date of wheat is 20 September to 1 October and suitable cultivars are SKW 191 and HS 240. Further rice can be cultivated in wheat-rice sequence under mechanised agriculture.|
|Description:||PhD Thesis submitted to SKUAST Kashmir|
|Appears in Collections:||Thesis|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.