Mercury level is dipping – Know which Rabi crops can get affected

Most of us would be aware that crops are dependent on light, temperature, moisture and carbon dioxide concentration in order to produce the grains and other crop products (which are crucial to our nutrition and health). But the levels of these variable inputs, such as rainfall, and temperature have deviations location wise every year. 

Temperature variations can result in implications for crop production, and the livelihood of crop producers. Crop management is therefore about managing climate risk as well, in order to provide a financially viable and sustainable agricultural system to the feeding population. These climatic changes can ultimately have an impact on global trade, with implications for net exporters, net importers and consumers, also for national and global food security.  

Temperature plays an important role in photosynthesis & respiration, plant growth and phenological development. Phenology is the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life. Extreme temperature can be often detrimental for crop yields growth and can even result in death of the plant.  As per the IMD, the next 6-8 weeks are expected to be dominated by frequent and intense episodes of cold waves in the country. The main factor behind the chilling winter forecast is the prevailing weak La Niña over the Pacific Ocean since August 2020. Already the Northern part of the country has started feeling the impact of mercury levels (I.e. temperature) dipping. Let us know about the temperature conditions preferable in cultivation of major Rabi crops, because in forthcoming weeks it will be crucial to monitor the effect of temperature variations over the yields and the crop size.  

1. Chickpeas: This crop performs optimally in 21° to 26° C during daytime and around 18° to 21°C at nights.   Cold stress adversely affects the mobilization of food reserves from cotyledons that decreases embryonic growth, germination, and growth of chickpea seedlings 

2. Mustard: Temperature about 15-25°c is suitable for the cultivation, and the effect of low temperature (frost) during pods and seed development stage, leads to freezing injury in seeds and significant reduction in the yield.  

3. Cumin :The seeds need 2 to 5 °C (36 to 41 °F) for emergence, and an optimum of 20–30 °C (68–86 °F) is suggested by scientists. This crop therefore requires a relatively cooler climate, but vulnerable to frost damage, especially at flowering and early seed formation stages. 

4. Maize: (Rabi season) is grown in temperatures between 18°C and 27°C during the day and around 14°C during the night. But the most important factor is the 140 frost-free day during its growth phase.  

5. Coriander: is a cool-season crop that grows best at temperatures between 10 and 30 degrees C. It can tolerate temperatures as low as -12 degrees C, but if temperature exceeds 30 degrees C it will start to bolt. Bolting is the production of a flowering stem (or stems) on agricultural and horticultural crops before the crop is harvested, in a natural attempt to produce seeds and reproduce.  

6. Barley: The crop requires around 12-15 degree C during growing period and around 30 degree C at maturity. It cannot tolerate frost at any stage of growth and occurrence of frost at flowering stage is highly detrimental for yield.