JNTU B.Pharmacy IV HERBAL DRUG TECHNOLOGY Previous Question Paper (July/August-2022 - R17)

A pest is any organism—including insects, rodents, weeds, fungi, or bacteria—that interferes with the cultivation, growth, or storage of medicinal plants, causing economic loss or reduction in quality. Pest control involves integrated strategies to manage these populations.

Methods of pest control include:

1. Cultural Methods: These involve modifying the environment to make it less favorable for pests. Examples include crop rotation to break pest life cycles, intercropping with repellent plants (e.g., marigolds), and maintaining proper field sanitation to remove breeding sites.
2. Physical/Mechanical Methods: These involve direct physical barriers or removal. Examples include the use of nets, traps, hand-picking of insects, and using mulches to suppress weeds.
3. Biological Methods: This utilizes natural enemies to control pest populations. Examples include introducing predators like ladybird beetles to control aphids or using microbial agents like Bacillus thuringiensis to target specific larvae.
4. Chemical Methods: The use of pesticides or herbicides. Under Good Agricultural Practices (GAP), this is the last resort. Examples include the use of neem-based formulations or pyrethrum, which are botanical insecticides preferred for medicinal crops to minimize toxic residues.

Harvesting is a critical stage in the production of medicinal plants, as it directly impacts the concentration of active chemical constituents. According to Good Agricultural Practices (GAP), the process must be systematic:

1. Timing of Harvest: Plants must be harvested at the peak of their active ingredient concentration. This is determined by the plant's growth stage (e.g., before flowering for leaves, at full bloom for flowers, or during dormancy for roots).
2. Environmental Conditions: Harvesting should be performed during dry, cool weather, ideally in the early morning after dew has evaporated, to prevent microbial growth and degradation of thermolabile compounds.
3. Technique: Tools must be clean, sharp, and disinfected to prevent mechanical damage and cross-contamination. Harvesting should be performed in a way that avoids soil contamination, particularly for roots and rhizomes.
4. Post-Harvest Handling: Harvested materials must be kept in clean, ventilated containers and protected from direct sunlight and moisture. They should be transported to the processing area immediately to prevent fermentation or enzymatic degradation.
5. Documentation: Every batch must be labeled with the plant name, date of harvest, location, and the name of the harvester to ensure full traceability throughout the supply chain.