Statement i: The National Mission for Sustainable Agriculture has 10 key dimensions to promote sustainable agricultural practices.
Statement ii: It emphasizes the need to harness traditional knowledge for in-situ conservation of genetic resources.

Both statements i and ii are correct.

Explanation:
The National Mission for Sustainable Agriculture (NMSA) is one of the eight missions under the National Action Plan on Climate Change. It aims to make agriculture more productive, sustainable, and resilient to climate change. The mission focuses on various dimensions to promote sustainable agricultural practices. Some of these dimensions include:

1. Soil health management: The NMSA promotes the use of organic manure, crop rotation, and integrated nutrient management to improve soil health and fertility.

2. Water use efficiency: It encourages the adoption of techniques like drip irrigation, sprinkler irrigation, and rainwater harvesting to optimize water use in agriculture.

3. Seed production and distribution: The NMSA supports the production and distribution of high-quality seeds to ensure better crop yield and genetic diversity.

4. Crop diversification: It promotes the cultivation of a variety of crops to reduce risks associated with mono-cropping and to enhance farmers' income.

5. Livestock management: The mission aims to improve livestock management practices, including breed improvement, animal health care, and fodder development.

6. Pest and disease management: It emphasizes the adoption of integrated pest management techniques, use of biopesticides, and proper disease surveillance to minimize crop losses.

7. Market linkages: The NMSA focuses on creating market linkages for farmers to ensure fair prices for their produce and reduce post-harvest losses.

8. Capacity building: It emphasizes the need for training and capacity building of farmers, extension workers, and other stakeholders to enhance their knowledge and skills in sustainable agriculture.

9. Climate-resilient agriculture: The mission promotes the adoption of climate-resilient agricultural practices to mitigate the adverse effects of climate change on agriculture.

10. Harnessing traditional knowledge: The NMSA recognizes the importance of traditional knowledge in sustainable agriculture and aims to harness this knowledge for the in-situ conservation of genetic resources.

Therefore, both statements i and ii are correct as the NMSA does have 10 key dimensions to promote sustainable agricultural practices, and it also emphasizes the need to harness traditional knowledge for in-situ conservation of genetic resources.