The answer to your first question is NO. Principles and discoveries of a scientific nature, such as the biological process on plant production, as you have discovered and developed, are not patentable under Nigeria's Patents and Designs Act. This is because they are not inventions but merely principles and discoveries.
Regarding your second question on disclosing the details of your invention, including drawings, you require a confidentiality or non-disclosure agreement.
Though you didnt ask, your Harmarain biological plant process may not be patentable in Nigeria.
Principles and discoveries of a scientific nature are not patentable because they are not inventions in the first place.
Section 1(5) of Nigeria's Patents and Designs Act states that principles and discoveries of a scientific nature are not inventions for the purposes of the Act.
Though the Act requires that for an invention to be patentable, it must be new, be a result of an inventive activity, and capable of industrial application, the Act does not accept principles and discoveries of a scientific nature to be inventions at all.
Did the drafters of the Act see these principles and discoveries as some kind of magic or voodoo that should never be granted patent? No. Patents are granted for application of knowledge to provide industrial solutions (just as others create new problems!), not for knowledge itself. Principles and discoveries are a body of knowledge, not inventions.
So a patent may not be granted for discovery of the science of solar energy, for example, but patents have been granted for inventive solar-powered panels.
To prevent the disclosure of your invention including drawings, get the patent agent to sign a confidentiality or non-disclosure agreement.
One irony about patent is disclosure. Before you can get a grant of patent, you have to fully disclose your invention when filing your application for patent. Section 3(1)(a)(ii) of the Patents and Designs Act requires a description of the relevant invention with any appropriate plans and drawings. For this purpose, you are required to disclose the relevant invention in a manner sufficiently clear and complete for the invention to be put into effect by a person skilled in the art or field of knowledge to which the invention relates—section 3(2) of the Act. If the patent agent gets this wrong, the patent may be invalidated in a court of law. So disclose sufficiently.
Apart from when filing patent applications, disclosing your invention before applying for patent is unavoidable in certain situations. Business partners, potential inventors, or—in this case—patent agents may require this. If you say NO, you may never be an inventor. Instead, use a confidentiality or non-disclosure agreement. Use it before you disclose, never after so you can be happy ever after.
Avoid simply downloading just any confidentiality or non-disclosure agreement—or any legal document for that matter—online. Simply downloading a template or a completed one from the Internet may be dangerous. You may pay more for it eventually when things go wrong. And it may be too late to fix it.
Always have your confidentiality or non-disclosure agreement well-drafted and well-reviewed by an IP attorney, tailored to your use.
Bad News: Harmarain may not be patentable in Nigeria because the invention is in respect of a biological process for plant production.
Sorry to break the news.
This is the position in section 1(4)(a) of Nigeria's Patents and Designs Act. It states that patents cannot validly be granted or obtained in respect of plant or animal varieties, or essentially biological processes for the production of plants or animals.
Except you are able to show in your specification that Harmarain is a product of a microbiological process in your plant production, it is not eligible for grant of patent in Nigeria.
For a comprehensive legal advice and guidance, you may consult an IP lawyer or law firm.
Follow-up questions, if any, are welcomed.