Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges & Opportunities
during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
date of planting were exposed to the exceptionally lower minimum temperature (below 10°C)
for about 9 weeks (49 to 5 th SMW). The 54.2 percent increase in fruit yield under black
polythene as compared to the non-mulched condition might be attributed to the fact of
recording of higher soil temperature (weekly mean), particularly during 49thto 5thSMW by up
to 1.84°C under black polythene as compared to non-mulched condition.
Thermal indices:
Irrespective of mulching treatments, the GDD accumulation from planting to end of the fruit
harvest in tomato variety Arka Rakshak reduced from 2140 to 1463°C Day, when planting the
tomato cultivar was delayed from 25 th October to 3 rd December, but it again increased to
1687°C Day when planting was further delayed to 8th January. Irrespective of planting dates,
the highest GDD accumulation to attain the end of harvest from planting was observed under
black polythene (1857°C Day), followed by rice straw (1784°C Day) and non-mulched
treatment (1669°C Day), which might be due to increasing in crop duration as a whole under
black polythene.
Day temperature accumulation from planting to the end of the harvest was the highest on the
first date of planting (3526°C) and lowest on the third date of planting (2502°C) without
considering the effect of mulching treatment. The marginal increase in accumulated Day
temperature on the last date of planting compared to the third date of planting was probably
due to exposure of both vegetative as well as reproductive stages of the last planting to a
continuous rise in both daily maximum and minimum temperatures. Irrespective of planting
dates, the highest Day temperature accumulation from planting to physiological maturity was
observed under black polythene (3064°C), followed by rice straw (2955°C) and non-mulched
treatment (2782°C Day). The lower coefficient of variation of Day temperature accumulation
to attain any maturity as compared with GDD is the indication of the efficiency of Day
temperature as a better thermal index.
The heat use efficiency (HUE) for fruit yield was influenced by both dates of planting and
mulching treatments. Irrespective of mulching treatments, HUE for fruit yield ranged from 1.3
to 5.2 kg ha -1 °C -1 , respectively. Relatively higher HUE recorded under the second date of
planting as compared to later dates of plantings was possibly due to higher fruit yield in the
crop planted on 14th November. Perhaps for the same region, HUE for both biomass and fruit
yields was highest under black polythene (5.4 and 3.6 kg ha -1 °C -1 ) mulch as compared to rice
straw (4.9 and 3. kg ha -1 °C -1 ) and non-mulched condition (3.6 and 2.3 kg ha -1 °C -1 ).
Correlation studies between crop growth parameters and fruit yield, and thermal indices
(Thermal time, Day temperature, and Heat use efficiency) confirmed the existence of a
significant and positive correlation between fruit yield and thermal indices. Therefore, these
indices can be utilized for developing equations for predicting the fruit yield of the tomato.
Ecosystem based approaches for climate change adaptation, ecosystem services, integrated farming system
models, Land degradation neutrality
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