Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges & Opportunities
during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
Results
Variation of air temperature during the crop growth period:
The variation of daily maximum temperatures during the growing period of the crop (from 25 th
October 2019 to 12 th May 2020) ranged from 21.7 to 31.7°C with an average temperature and
coefficient of variation of 26.7°C and 11.7 percent, respectively. The weekly maximum
temperature recorded in the second week of the crop season was 30.4°C, which reduced
continuously and reached the minimum of 20.7°C during 1 st SMW. Thereafter, the weekly
maximum temperature started to increase and reached a maximum value of 31.7°C during the
13 th standard week. It was observed that the daily maximum temperature never exceeded
34.6°C during the crop growth period and always remained lower than the maximum cardinal
temperature (38°C). However, increasing the daily maximum temperature above 30°C after
mid-March (11 SMW) was detrimental to the growth and yield of the crop as it was well above
the optimum cardinal temperature of 18 to 24°C of the crop.
The mean daily minimum temperatures during different standard meteorological weeks in the
crop growing season varied from 8.4°C to 20.8°C at 2 nd SMW and 19 th SMW, respectively.
From the 45thSMW onwards, the minimum temperature decreased gradually and attained the
minimum value of 8.4°C at 52 nd SMW, thereafter, it increased gradually and became 20.8°C at
18 th SMW. It was observed that the mean daily minimum temperature during the first week of
December to the first week of February remained below 10°C, with the maximum limit of
6.2°C, which was even lower than the base temperature (7°C) of the crop.
Variation of soil temperature under different microclimates
The weekly mean morning and evening soil temperatures ranged from 11.4 to 23.7°Cand 15.1
to 34.5°C, respectively under different planting dates and mulching treatments (Fig. 1). The
highest morning soil temperatures with a weekly mean of 16.9°C were recorded under P1,
which reduced gradually with successive delay in planting with the mean morning soil
temperatures of 15.7 (P 2), 15.3 (P 3) and 14.9°C (P 4). The highest and the lowest mean evening
soil temperature of 26.3°C and 23.6°Cwere recorded under P1 and P2, respectively. Like
morning soil temperature, evening weekly average soil temperatures reduced gradually in the
last two dates of plantings (P 3 and P 4). As expected in all planting dates irrespective of the
mulching treatments, both weekly morning and evening soil temperatures started to decline
from 47 th SMW and became the minimum between 1stto 3 rd SMW, thereafter it started to
increase gradually towards the end of the crop season. Thus, the early stages of crop growth of
the first planting were exposed to higher soil temperatures, while in reproductive growth stages
of that planting were exposed to lower temperatures. On the other hand, early and later growth
stages of the crop planted on later dates (P3 and P4) were sequentially exposed to lower and
higher soil temperatures.
Ecosystem based approaches for climate change adaptation, ecosystem services, integrated farming system
models, Land degradation neutrality
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