Question

Give one significant contribution to the following scientist. P. Maheshwari.

Answer 1

Hint: We know that The Panchanan Maheshwari was an eminent Indian botanist and he was known for his discovery in the technique of test-tube fertilization of angiosperms. With the invention of this technique, it becomes easier to develop the plant varieties that earlier can’t be produced by natural crossbred techniques.

Complete answer:
- Panchanan Maheswari was an eminent Indian botanist and he was known for his discovery in the technique of test-tube fertilization of angiosperms.
- Test tube fertilization or in vitro fertilization is a type of process involving fertilization where the egg is fused with the sperm outside i.e. in a glass or test tube. The whole process is monitored as the fertilized egg is developed into an embryo.
- Cultivation of plant tissue and other organs on an artificial media in a test tube is in vitro technique.

This process takes place in three different ways
> Stigma fertilization- in this method an anther is removed from the flower. The flower is sterilized and then isolated in vitro. Pollen from a ripe anther (sterilized) is then placed on the stigma.
> Placental fertilization- the ovules of the flower dissected and placed on a nutrient medium then the anthers are opened under sterile conditions and the pollen grains placed near the ovules.
> Fertilization of an ovule by removing a placenta

- This technique is followed by members of Caryophyllaceae, Gossypium and Zea mays, etc.

Note: There are some barriers also during in vitro pollination and fertilization
- Pollen lacking the ability to germinate on foreign stigma.
- Bursting of pollen tube in style.
- Failure of the pollen tube to reach the ovule.