Question

Which of the following is an example of a weed of Rabi season that infests wheat crops?
A) Chenopodium
B) Motha
C) Jowar
D) None of the above

Answer 1

Hint: Rabi crops are best cultivated from October to March (that is in the winter season). These crops include pea, wheat, gram, linseed, mustard. Weeds that are found responsible for the majority of problems are: Phalaris minor (also known as Canary grass), Avena fatua (also known as Wild oat) and Polypogon monspeliensis.

Complete answer:
Weeds are the unwanted or undesirable plants that might be found growing along with the cultivated crops in the field. They take up the nutrients being supplied for the proper cultivation of desirable species thus starving the crop nutritionally. Thus protection of crops from the weeds is necessary for the improved growth of crops. Wheat farms are mostly affected by Chenopodium which grows at a fast pace round the year.
On the other hand, motha or C. Rotundus mostly affects the sugarcane and cotton crops while Jowar is itself a crop.

Thus, the correct answer is option “A” that is Chenopodium is a weed of Rabi season that infests wheat crops.

Note: Wheat favors lengthy days and high temperature during their reproductive phases while in vegetative phase it requires low temp. Optimum temperature in reproductive phase and vegetative phase is 20-22 degree Celsius and 16-22 degree Celsius respectively. A decrease in height of plant, tiller number and length of root is observed as temperature goes above 22 degree Celsius. Weeds are extremely harmful for the crop therefore proper prevention measures are necessary in early stages of crop cultivation. Monocots can be protected by use of chemicals such as Isoproturon, Methabenzthiazuron and Metoxuron.