UTTAR PRADESH JOURNAL OF ZOOLOGY

Callosobruchus chinensis is an important storage pest of black gram (Vigna mungo), and a wide range of plant materials have been tested as possible grain protectants. This narrative review examines powders, extracts, fixed oils and essential oils, giving greater weight to experiments conducted directly on black gram while using studies on other pulses as supporting evidence. Rather than comparing mortality values alone, the studies were considered in relation to dose, exposure period, persistence, controls and effects on grain quality. Some black gram experiments reported complete adult mortality within seven days, whereas black pepper was reported to protect grain for as long as 150 days at the tested doses. For selected plant oils, reported mortality half-lives were about 83–87 days. Peppermint oil also remained active during a four-month experiment, although mortality declined from 93.33% to 80% and appreciable mortality occurred in the untreated control. Because the studies differed substantially in design and measured outcomes, they do not support a simple ranking of treatments. Taken together, the available evidence makes black pepper, neem-based preparations and some plant oils useful candidates for further work. Their practical value, however, will depend on sustained suppression of adult emergence and grain loss without unacceptable effects on germination, food safety, sensory quality or cost.