Question

Choose the incorrect statements among the following I. Hairy leaves in plants are associated with resistance to insect pest.
II. Solid stem of wheat rejects stem saw fly.
III. Smooth leaves and nector less cotton attracts bollworms.
IV. Resistance to maize stem borer is by low aspartic acid and high nitrogen and sugar.

• A. I, II
• B. II, III
• C. III, IV
• D. II, IV

Hint:

Remember specific examples of morphological and biochemical adaptations in plants for pest resistance: \begin{itemize} \item \textbf{Hairy leaves (e.g., cotton, jassids):} Provide physical resistance to insects. \item \textbf{Solid stems (e.g., wheat, stem sawfly):} Act as a physical barrier against pests. \item \textbf{Smooth leaves/nectar-less (e.g., cotton, bollworms):} Offer resistance by making feeding or egg-laying difficult. \item \textbf{Chemical composition (e.g., maize, stem borer):} High aspartic acid and low nitrogen/sugar content contribute to resistance. \end{itemize}

Answer 1

The Correct Option is C

Step 1: Analyze Statement I)
Statement I says: "Hairy leaves in plants are associated with resistance to insect pest."
Hairy leaves (presence of trichomes) can indeed provide resistance to insect pests. For example, hairiness in cotton leaves provides resistance to jassids.
Therefore, Statement I is Correct. Step 2: Analyze Statement II)
Statement II says: "Solid stem of wheat rejects stem saw fly." In wheat, varieties with solid stems are known to resist the stem sawfly.
Therefore, Statement II is Correct. Step 3: Analyze Statement III)
Statement III says: "Smooth leaves and nector less cotton attracts bollworms."
In cotton, smooth-leaved and nectar-less varieties do not attract bollworms. Instead, they offer resistance to bollworms, as the absence of nectar and smooth surfaces makes it difficult for bollworms to feed or lay eggs. Therefore, the statement that they "attracts bollworms" is Incorrect. Step 4: Analyze Statement IV)
Statement IV says: "Resistance to maize stem borer is by low aspartic acid and high nitrogen and sugar."
Resistance to maize stem borer in maize is actually due to high aspartic acid, and low nitrogen and sugar content in the plant. These chemical characteristics make the plant less palatable or suitable for the borer.
Therefore, the statement is Incorrect. Step 5: Identify the incorrect statements
Based on the analysis:
Statement I is Correct.
Statement II is Correct.
Statement III is Incorrect.
Statement IV is Incorrect.
The question asks to choose the incorrect statements. The incorrect statements are III and IV. Step 6: Choose the correct option
The option that contains both III and IV is (3).