Question

Which of the following statements is not correct ?

• A. Insects that consume pollen or nectar without bringing about pollination are called pollen / nector robbers.
• B. Pollen germination and pollen tube growth are regulated by chemical components of pollen interacting with those of the pistil
• C. Pollen grains of many species can germinate on the stigma of a flower, but only one pollen tube of the same species grows into the style
• D. Some reptiles have also been reported as pollinators in some plant species

Answer 1

The Correct Option is D

Option 1: "Insects that consume pollen or nectar without bringing about pollination are called pollen/nectar robbers." 
This statement is correct. Insects that visit flowers to consume pollen or nectar but do not contribute to the pollination process (i.e., they do not transfer pollen from one flower to another) are called "pollen robbers" or "nectar robbers." They take resources from the plant without aiding in its reproductive process.

Option 2: "Pollen germination and pollen tube growth are regulated by chemical components of pollen interacting with those of the pistil." 
This statement is correct. The process of pollen germination and the growth of the pollen tube is regulated by chemical signals. These signals come from the pistil (the female part of the flower). Chemical components in the pistil attract the pollen tube, which grows through the style to reach the ovary for fertilization to occur.

Option 3: "Pollen grains of many species can germinate on the stigma of a flower, but only one pollen tube of the same species grows into the style." 
This statement is correct. When pollen grains land on the stigma of a flower, they begin to germinate. However, only one pollen tube (from the same species) will grow down the style to reach the ovary. This ensures that the right pollen from the correct species fertilizes the ovules.

Option 4: "Some reptiles have also been reported as pollinators in some plant species." 
This statement is incorrect. While some reptiles have been observed interacting with plants, they are not typical pollinators. Reptiles like lizards or iguanas may occasionally visit flowers, but their role in pollination is minimal compared to insects (such as bees) or birds (such as hummingbirds), which are the primary pollinators for many plants. The primary pollinators of most plant species are insects, birds, and sometimes mammals.

Conclusion: The incorrect statement is Option 3. While reptiles may occasionally interact with flowers, they are not considered important or common pollinators. Pollination is mainly carried out by insects, birds, and sometimes mammals. Thus, Option 3 is the answer that is not correct.