Data from: Impact of planting and harvest dates on yam infestation by white grubs

The white grub, Diaprepes abbreviates L. (Coleoptera: Curculionidae), is a
significant pest of yam tubers and the second cause of tuber rot in Haiti.
Larval feeding inflicts severe damage to tubers, leading to notable losses
due to decreased tuber quality, reduced marketability, and increased
susceptibility to secondary parasites and pathogens. This study examined
the influence of planting and harvesting dates on the vulnerability of yam
tubers to white grub infestation and the resulting tuber quality across 24
farmers’ fields. At harvest, we assessed the level of tuber infestation,
white grub density, and the tuber quality index. The results indicated
that 85% of grub populations were found in fields planted on the
traditional date. In addition, 69.5% of tuber damage occurred in
early-planted fields with fewer tubers damaged (30%) when harvested early.
In contrast, in fields planted 30 days after the traditional date, the
harvest date did not affect tuber infestation and damage by the pest.
Overall, both planting and harvest dates impacted the quality grade of yam
tubers. Delayed planting by 30 days and early harvesting (34th -38th week
after planting) improved the marketability of yams. These findings
highlight the importance of optimizing planting and harvest schedules to
better manage white grub infestation and enhance the marketability of yam
tubers.