Climatic requirement

• Rice is heat and water loving plant, requiring high temperature and adequate moisture supply.
• For germination a minimum of 10^oC and for flowering a temperature of 22-25^oC is considered as an optimum. Grain formation takes place at 20-21^oC.
• Low temperature particularly during 10-11 days before heading causes considerable loss in grain yield because of sterile spikelets.
• At ripening temperature should be in between 20-25^oC.
• Rice is a short day, thermosensitive plant but now many thermoinsensitive varieties have been developed.
• It is mostly grown in areas receiving 1000-1500 mm rain.