Study on the loss of value of Khodari date fruit infested by almond moth (Lepidoptera: Pyralidae)

Postharvest almond moth (Cadra cautella Walker; Lepidoptera: Pyralidae) infestation is one of the primary challenges for production of dates,
Phoenix dactylifera L. (Arecaceae) cv. ‘Khodari.’ This study was a simulation of early almond moth infestations in uncontrolled storage conditions. It
aimed to investigate the effects of low level almond moth infestations on the population growth of the moth, the damage to the dates, bacterial and
fungal contamination, and the nutritional value of the dates. One, 2, and 3 pairs of male and female moths were introduced into 250 g Khodari date
samples. Noninfested dates were used as controls. Each treatment was performed in 10 replicates. The results showed a more than 25-fold increase
in the almond moth population and significant damage to the dates. The moth population in the 2 pair treatment was the highest. Moth infestation
also increased microbial contamination by more than 3-fold compared with noninfested dates. The treatment of the 3 pairs of moths significantly
increased the bacterial load more than 20-fold when compared to the control. The fungal contamination in the 2 and 3 pair treatments were more
than 5-fold higher than that of the control. In contrast, the moth pairs did not significantly affect the sugar, protein, fiber, ash, or water contents of
dates. The results suggest that infestation by a single pair of almond moths at the initial stage postharvest causes significant damage and contamina-
tion in Khodari dates.
Key Words: dates; almond moths; Cadra cautella; microbial contamination; nutrition