期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2009
卷号：XXXVIII-8/W3
页码：44
出版社：Copernicus Publications
摘要：Cotton cultivation in semi-arid region of Indian Punjab provides the full potential to offer livelihood security to millions of marginal and small farmers. But the farmers consider it most risky crop as its yield varies with season and prices fluctuate in the market largely. Temporally, its production has increased from 176 lakh bales in 1996-97 and an all time record of 280 lakh bales during 2006-07. This record production became possible only due to the good weather and introduction of Bt cotton hybrids. The unpredictability of cotton yield is a great concern to the cotton industry. Many factors, such as length of the growing season, climate (including solar radiation, temperature, light, wind, rainfall, and dew), cultivar, availability of nutrients and soil moisture, pests, and cultural practices affect cotton growth. Of these, it is thought that environmental factors exert the major influence on yield development during each season. Temperature is considered to be one of the main environmental factors contributing to variable yields in cotton. Till now limited information exists on the effects of temperature on Bt cotton growth and yield in this region. To generate such information CropSyst model was used rather than field experimentation as the later is not feasible due to difficulty in controlling/ creating variability in weather parameters. The model was customized using the data of crop, soil and weather for an experiment conducted on Bt cotton hybrid RCH 134 during 2005 at Bathinda and simulations were made for 15 years 1991-2005. From the simulated results, relationships between temperature and duration of total crop growth period as well as of phenophases (sowing to flowering, flowering to boll formation and boll formation and maturity) and subsequently between duration of phenophases and cotton seed yields were developed. The results indicated that by the increase in temperature from 28 to 32 oC cotton seed yield decreased from 4700 to 2300 kg ha-1following a linear relation with high coefficient of determination (0.97) and the reduction was more during sowing to flowering stage than others. Regarding water relationships, real crop water productivity was more (10.2 kg mm-1) than apparent (8.8 kg mm
