Tikka disease, a common fungal disease causing characteristic leaf spots, is primarily associated with which of the following crops?

Introduction:
Plant diseases significantly reduce crop yield and quality, and certain diseases are very closely associated with specific crops. Tikka disease is a well known example in Indian agriculture, frequently mentioned in competitive exams under plant pathology and agronomy sections. This question checks whether you can correctly link tikka disease to the crop on which it is classically reported.

Given Data / Assumptions:
- The disease named in the question is tikka disease. - The crop options are mustard, paddy (rice), groundnut and all of these. - Tikka disease is known for causing round or irregular brown spots on leaves. - We assume standard Indian cropping systems and disease names used in agricultural universities.

Concept / Approach:
Tikka disease is a leaf spot disease that specifically attacks groundnut (Arachis hypogaea). It is caused mainly by fungi such as Cercospora arachidicola and Cercosporidium personatum. The disease produces small circular brown lesions on the leaves, which may coalesce and cause leaf shedding, reducing photosynthetic area and yield. Mustard and paddy have their own characteristic diseases such as powdery mildew and blast, but the name tikka disease is strongly linked with groundnut. Therefore, groundnut is the correct answer.

Step-by-Step Solution:
Step 1: Recall the common crop disease pairs, such as rust in wheat, blight in potato and tikka disease in groundnut. Step 2: Connect the term tikka with the appearance of small dots or spots, similar to the spots on groundnut leaves. Step 3: Recognise that mustard and paddy do not typically have a disease commonly called tikka in standard agronomy texts. Step 4: Discard the all of these option because tikka disease is not a general term for diseases in all the listed crops. Step 5: Select groundnut as the specific crop affected by tikka disease.

Verification / Alternative check:
Plant pathology books and agricultural extension pamphlets describe tikka disease of groundnut in detail, including symptoms, causal organisms and control measures such as fungicidal sprays and resistant varieties. The disease is considered economically significant in many groundnut growing regions. These descriptions consistently use the name tikka disease for groundnut, not for mustard or paddy, confirming that groundnut is the correct association.

Why Other Options Are Wrong:
Mustard: Suffers from diseases like white rust and downy mildew, but tikka disease is not the usual name for any mustard disease. Paddy (rice): Common diseases include blast, bacterial leaf blight and sheath blight; none of these is widely called tikka disease. All of these: Incorrect because tikka disease is specific to groundnut and not a general name for leaf spots in multiple crops.

Common Pitfalls:
Some learners may misinterpret tikka as a generic term for spots and think it might apply to several crops, leading to the selection of all of these. Others may not recall the exact crop and guess based on familiarity with mustard or paddy. To avoid such mistakes, it helps to memorise common disease crop pairs: for example, tikka disease with groundnut, loose smut with wheat, and blast with rice. This pattern based recall is very useful in agriculture related questions.

Final Answer:
Tikka disease is primarily associated with the Groundnut crop.