Wheat is the second major cereal crop in India after paddy. It plays an important role in food and nutritional security of the country.
Excess temperature affects seed germination. The seeds must have sufficient moisture to germinate. High temperature increases evaporation of soil and seeds.
Due to this, there is a lack of moisture in both soil and seed.
To get proper yield from wheat crop, it is most important that sowing should be done at the right time.
Seed germination affected at both the highest and lowest temperatures.
In India, wheat is sown from mid-October to November. All stages of crop growth and development are sensitive to temperature.
Temperature is the main factor controlling the growth rate of the crop. At the time of vegetative growth in wheat crop, the establishment & tillering of the crop affected when maximum temperature exceeding 30°C and due to this, yield of the crop also reduced.
Due to the damage caused by high temperature in vegetative stage, the yield decreases despite getting favourable temperature at the time of flowering.
The adverse effect of high temperature mainly affects the fertilization of the crop. This affects pollination, due to which there is a huge reduction in the number of grains in the earrings.
In wheat crop, the growth of grains is good when the maximum temperature for grains is between 10-15 to 13-18 °C. When the temperature rises from 10-21 to 25-30 °C, the growth and size of grains decrease by about 38 percent.
Short periods of moderately high temperatures (25-30 °C) and very high temperatures (33-40 °C and above) during grain filling also severely affect the yield and yield factors of wheat.
Often, the dry weight of wheat crop declines at high temperatures. The crop sown at the appropriate time provides the proper amount of dry weight.
Therefore, to take more production from the crop, it is more important that the crop should be sown at the right time, so that the crop can be saved from the damage caused by the rising temperature in the environment.