Quantifying the thermal heat requirement of Brassica in assessing biophysical parameters under semi-arid microenvironments |
| |
Authors: | Tarun Adak N V K Chakravarty |
| |
Institution: | (1) Division of Agricultural Physics, Indian Agricultural Research Institute, Pusa Campus, New Delhi-12, India |
| |
Abstract: | Evaluation of the thermal heat requirement of Brassica spp. across agro-ecological regions is required in order to understand the further effects of climate change. Spatio-temporal
changes in hydrothermal regimes are likely to affect the physiological growth pattern of the crop, which in turn will affect
economic yields and crop quality. Such information is helpful in developing crop simulation models to describe the differential
thermal regimes that prevail at different phenophases of the crop. Thus, the current lack of quantitative information on the
thermal heat requirement of Brassica crops under debranched microenvironments prompted the present study, which set out to examine the response of biophysical
parameters leaf area index (LAI), dry biomass production, seed yield and oil content] to modified microenvironments. Following
2 years of field experiments on Typic Ustocrepts soils under semi-arid climatic conditions, it was concluded that the Brassica crop is significantly responsive to microenvironment modification. A highly significant and curvilinear relationship was
observed between LAI and dry biomass production with accumulated heat units, with thermal accumulation explaining ≥80% of
the variation in LAI and dry biomass production. It was further observed that the economic seed yield and oil content, which
are a function of the prevailing weather conditions, were significantly responsive to the heat units accumulated from sowing
to 50% physiological maturity. Linear regression analysis showed that growing degree days (GDD) could indicate 60–70% variation
in seed yield and oil content, probably because of the significant response to differential thermal microenvironments. The
present study illustrates the statistically strong and significant response of biophysical parameters of Brassica spp. to microenvironment modification in semi-arid regions of northern India. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|