Plant Breeding, Biotechnology and Biostatistics – Botany Optional PYQs (1995–2026)

Here are all 135 Plant Breeding, Biotechnology and Biostatistics questions asked in UPSC Botany Optional Paper II from 1995 to 2026, arranged under the 5 topics of the official syllabus. Within each topic the latest questions come first.

Each question ends with a code such as [2024/15m/3b] – the year, the marks, the word limit (where UPSC set one) and the question number in the paper.

3.1] Methods of plant breeding

20 questions

1. Explain in detail the various methods of plant hybridization. [2025/15m/3c]

2. Explain how mass selection will be of help in a successful breeding program. Elaborate the answer with a suitable example. [2024/15m/4b]

3. What are the major requirements for a successful back-crossing programme? Describe its procedure, advantages and limitations. [2023/15m/3a]

4. Write brief notes on the following: (i) Southern blotting (ii) RT-PCR (iii) Mass selection. [2017/15m/4c]

5. Back cross method. [2016/10m/4a]

6. Describe the method of developing disease and insect resistant varieties through back cross method of breeding crop varieties. [2015/15m/3c]

7. Discuss briefly the mechanism of disease resistance. [2015/15m/4c]

8. How would you develop improved variety of basmati rice for organic farming conditions? [2014/20m/2c]

9. Explain interspecific and intergeneric hybridization. Comment on Raphano-brassica. [2011/15m/5a]

10. Backcross method of breeding. [2009/20m/200w/1d]

11. Describe the methods of selection and hybridization used in plant breeding. [2007/30m/4a]

12. Techniques of breeding self-pollinated crops. [2006/20m/3a]

13. Define hybrid vigour. Describe anyone method of hybridization for crop improvement. [2005/60m/4]

14. Mass selection. [2004/20m/200w/1c]

15. Describe the back-cross method of breeding in crop varieties. [2004/30m/4a]

16. Describe in detail the various uses of back-cross method of breeding and its limitations. [2004/30m/4b]

17. Pure Line Selection. [2003/20m/200w/1c]

18. Give a brief account of hybridization work on India crop plants. [2000/60m/4]

19. M.S. Swaminathan. [1995/20m/4a]

20. Write a note on green revolution. [1995/20m/200w/5b]

3.2] Mutation, polyploidy and heterosis breeding

28 questions

1. Explain the significance of polyploidy in Agriculture. [2026/7m/3c(ii)]

2. Explain the causes of Heterosis and its impact in Agriculture. [2026/15m/4b]

3. Discuss in detail the role of mutations in plant breeding and crop improvement. [2025/15m/4c]

4. Explain briefly the process and importance of the following:

(i) Male sterility and heterosis breeding. [2024/5m/2a(i)]

(ii) Molecular basis of cell cycle. [2024/5m/2a(ii)]

(iii) Gene silencing. [2024/5m/2a(iii)]

5. Explain what is apomixis and how this may be of help in plant breeding? Elaborate the answer with suitable examples. [2024/15m/2c]

6. How male sterility helps in heterosis breeding? Discuss the application of barnase-barstar system in achieving heterosis. [2022/20m/4a]

7. Use of apomixis in plant breeding. [2021/10m/1e]

8. Describe the significance and uses of the following: (i) Male sterility (ii) Polyploidy in plant breeding. [2020/15m/2b]

9. Enumerate the different causes of heterosis. [2018/10m/3b(ii)]

10. Briefly describe the following terms and emphasize their applications: (i) Restriction endonucleases (ii) Mutation breeding (iii) Gene mapping. [2018/15m/4a]

11. Explain the importance of numerical and structural variations in chromosomes with respect to crop varieties. [2017/20m/2a]

12. What is apomixis? Write about its relevance in plant breeding. [2017/15m/2c]

13. Discuss Inbreeding depression versus Heterosis. [2016/15m/3b]

14. Hybrid vigour. [2015/10m/1d]

15. Giving reasons explain the following: Selection of cytoplasmic-genetic male sterility in the development of hybrid varieties. [2014/10m/1b]

16. Discuss the use of apomixes in plant breeding. [2012/15m/4d]

17. Describe the method of developing maize hybrids. [2010/30m/4b]

18. Discuss the origin, production and uses of haploids. [2009/30m/3a]

19. Male sterility. [2007/20m/200w/1c]

20. Define hybrid vigour. Describe anyone method of hybridization for crop improvement. [2005/60m/4]

21. Describe in detail the method of producing hybrid seeds using Cytoplasmic-genetic male sterility system. [2003/30m/3c]

22. Critically examine the following alternatives and substantiate with reasons which of the two is preferable: Mutation for breeding versus protoplast fusion for crop improvement. [2001/20m/4c]

23. Heterosis. [2000/20m/3a]

24. Genetic basis of inbreeding depression and heterosis. [1999/20m/200w/1d]

25. Male sterility in plants. [1998/20m/200w/5c]

26. What is male sterility? Explain its importance. [1995/20m/200w/1b]

27. What is mutation and how can it be induced? Write a note on mutation breeding with special reference to achievements made in India. [1995/60m/2]

28. Explain the term Hybrid vigour and write about its importance. [1995/30m/3b]

3.3] Genetic engineering and transgenic crops

41 questions

1. Reporter genes. [2026/10m/150w/1c]

2. What are the different methods of DNA sequencing? Elaborate the shotgun sequencing method. [2025/20m/2a]

3. What are transgenic crops? Discuss the prospects and risks involved in their cultivation. [2025/20m/6a]

4. What are the different gene transfer methods in plants? Give a brief account of direct gene transfer methods. [2025/20m/7a]

5. Discuss briefly the following and comment on their significance:

(i) In what way the transfer of genes in plants help in their sustainable development? Support the answer with an example. [2024/10m/4a(i)]

(ii) Importance of biosafety aspects of transgenic crops. [2024/5m/4a(ii)]

(iii) Polytene chromosomes. [2024/5m/4a(iii)]

6. Describe the problems associated with gene transfer in plants. Write a note on the status of transgenic research in India. [2023/20m/2c]

7. What is gene editing? Discuss its applications and advantages for genetic engineering. [2022/20m/3c]

8. How male sterility helps in heterosis breeding? Discuss the application of barnase-barstar system in achieving heterosis. [2022/20m/4a]

9. Describe the steps in DNA sequencing. What are its applications? [2022/15m/4b]

10. Discuss the biosafety concerns of transgenic plants. [2021/15m/3c]

11. Describe various methods of gene transfer in plants. [2021/20m/4a]

12. Transgenic technology is a breakthrough innovation. Justify with examples. [2020/20m/2c]

13. Describe sequentially the steps of T-DNA transfer process from Agrobacterium cell to plant nuclear genome. Write a brief note on achievements of ‘gene transfer technology’ in crop improvement. [2019/20m/3b]

14. Discuss two DNA sequencing methods with suitable illustrations. Name two fully sequenced eukaryotic genomes with their sizes. [2019/20m/4b]

15. Briefly describe the different methods of gene transfer in plants. [2018/10m/1e]

16. How are insect resistant transgenic plants developed? Which gene is used in this technology? Briefly explain the rationale of the technology. [2018/20m/2b]

17. Briefly describe the following terms and emphasize their applications: (i) Restriction endonucleases (ii) Mutation breeding (iii) Gene mapping. [2018/15m/4a]

18. Explain the significance and importance of the following with at least one example: (i) Gene silencing (ii) Multigene families (iii) Transgenic crops and their future. [2017/15m/3c]

19. Restriction endonucleases. [2016/10m/4b]

20. Transgenic plants as living bioreactors. [2016/10m/4c]

21. Retroviruses as vectors. [2016/10m/4e]

22. Biosafety and Bioremediation. [2016/10m/8d]

23. Describe briefly the various methods of gene transfer. [2015/20m/2c]

24. Explain antisense RNA technology with an example. Highlight its applications. [2011/15m/1c]

25. Discuss the mechanism of T-DNA transfer from Agrobacterium tumefaciens to host plant. [2011/15m/2a]

26. Comment on ‘EPSPS’ and ‘Tra’ genes. [2011/15m/3a]

27. Describe different methods of gene transfer in plants. [2011/15m/4a]

28. Highlight the biosafety aspects arising out of plant genetic engineering. [2011/15m/6b]

29. Explain the current developments in transgenic technology contributing to crop improvement. [2011/15m/7b]

30. How will you identify the expression of a cloned gene? [2011/15m/8b]

31. Describe in detail the Agrobacterium-mediated gene transfers in the development of transgenic crop plants. [2010/30m/4a]

32. Describe biosafety regulatory measures for raising transgenic crops. [2009/30m/3b]

33. Explain the methods of transfer of genes into plants. [2007/30m/3b]

34. Transgenic plants. [2005/20m/200w/1c]

35. What do you understand by genetic engineering? [2003/15m/4a]

36. Describe in detail the agrobacterium-mediated gene transfer method for producing transgenic plants. [2003/45m/4b]

37. How is recombinant DNA produced? What applications have been found for recombinant DNA? [2002/60m/3]

38. Describe the techniques of gene transfer to produce transgenic plants. Add a critical note on the importance of genetic engineering with special reference to the Indian agriculture. [2001/20m/200w/1c]

39. Critically examine the following alternatives and substantiate with reasons which of the two is preferable: Gene and genome mapping for selective cloning versus cloning without any restriction. [2001/20m/4b]

40. What is genetic engineering? Discuss its importance to agriculture, forestry and medicine. [1996/60m/8]

41. Genetic transformation. [1995/20m/4d]

3.4] Molecular markers and techniques

24 questions

1. DNA finger printing. [2026/10m/150w/1e]

2. Elaborate on the significance of molecular markers. [2026/8m/3c(i)]

3. Discuss on the tools and techniques involved in PCR and FISH. [2026/20m/4a]

4. Describe the procedure, requirements and efficiency level of gene amplification through Polymerase Chain Reaction (PCR). [2023/15m/4c]

5. Southern blotting. [2022/10m/150w/1e]

6. RAPD PCR – strength, weakness and application. [2022/10m/150w/5b]

7. Applications of probes in Southern blotting. [2020/10m/1a]

8. “DNA fingerprinting is important in any plant breeding programme.” Justify the statement with suitable examples. [2019/10m/1a]

9. Explain the importance of the following techniques: (i) FISH (ii) Molecular probe. [2018/10m/3c]

10. Elaborate on the use of molecular markers in plant breeding. [2017/15m/4b]

11. Write brief notes on the following: (i) Southern blotting (ii) RT-PCR (iii) Mass selection. [2017/15m/4c]

12. Explain and describe the tools and techniques of FISH. [2016/20m/2a]

13. Molecular markers. [2016/10m/4d]

14. Giving reasons explain the following: Use of FISH technique in tracking the target organisms. [2014/10m/1c]

15. What are molecular probes? Mention their applications in biology. [2014/15m/2b]

16. Explain how GISH can be used for identifying the putative ancestors of a plant. [2013/15m/2c]

17. Explain the importance of DNA–DNA hybridization techniques in the study of biodiversity. [2012/15m/4b]

18. What are gene markers? Explain their importance in biological studies. [2012/15m/4c]

19. What are primers? Explain their role in PCR. [2012/15m/7b]

20. What is the principle of blotting? Give an illustrated account of the steps involved in Southern blotting. [2012/15m/8b]

21. RFLPs. [2010/15m/150w/1c]

22. Explain FISH technique and its importance in understanding genomic relationships among species. [2010/30m/2a]

23. Give an account of the PCR based molecular markers and their applications in plant breeding. [2009/30m/4b]

24. Molecular markers in plant breeding. [2006/20m/200w/1d]

3.5] Biostatistics

22 questions

1. Correlation and Regression. [2026/10m/150w/5b]

2. Tests of significance. [2025/10m/150w/5a]

3. Probability and distribution are two important factors which should always be taken into account to establish a successful breeding programme. Explain with a suitable example. [2024/10m/150w/1e]

4. Correlation, its types and significance. [2023/10m/150w/1e]

5. In a cross between pea plants with green and yellow coloured pods, the $F_2$ individual segregated into 787 green and 277 yellow pod coloured individuals. If you have to test that these results agree with the expected ratio $3:1$, then apply Chi-square $P=5\%$. The control value of Chi-square at 0.05 for $d_f=2-1=1$ is $=3.84$. [2022/15m/2c]

6. What do you understand by standard deviation and coefficient of variation? Discuss their significance. [2021/15m/2c]

7. Describe Chi-square test and its applications in genetic study. [2020/10m/1e]

8. Which statistical test is used to determine whether the observed progeny of a cross fits or differs from the expected values? Name the test and briefly describe the steps involved. [2018/10m/2c]

9. Student’s $t$-test is a test of significance. Explain. [2017/10m/1e]

10. Chi-square test as a test of goodness of fit. [2016/10m/1c]

11. Giving reasons explain the following: Tests of significance in biology. [2014/10m/1e]

12. Chi-square test. [2013/10m/4d]

13. Normal distribution. [2010/15m/150w/1e]

14. .

(i) Comment briefly on the contributions made by Herman Nilsson-Ehle. [2009/15m/4a(i)]

(ii) List the important statistical methods of studying association and relationship between two variables. [2009/15m/4a(ii)]

15. Probability and distributions, with suitable illustrations. [2007/20m/200w/1d]

16. Uses and applications of correlation and regression analysis in plant genetics. [2006/20m/3c]

17. Standard deviation. [2005/20m/200w/1d]

18. ${\chi }^2$-test (Chi-square test) [2004/20m/200w/1d]

19. Explain ‘test of significance’ and comment on its application in Botanical Research. [2002/20m/200w/1c]

20. Binomial Distribution and Poisson Distribution. [2002/20m/4c]

21. Explain the concept of ‘standard error’ and comment on its application in various research programmes. [2001/20m/200w/1d]

22. Test of significance. [2000/20m/200w/1d]

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Last updated: 31 October 2026