Impact of Seed Corn Maggot on the Three Sisters Crop System: Investigating Host Preference and Performance

In 2027, New York will place a state-wide ban on neonicotinoid pesticides which have had several negative effects on pollinators. Due to this ban, many farmers are concerned about the new risk of previous pests that were killed by neonicotinoids, rampaging their fields. Delia platura, or seed corn maggot, are flies whose larvae attack crop seeds and are one of the pests previously killed by neonicotinoids. Many farms plant the Three Sisters crops: corn, climbing beans, and squash. Though research shows D. platura targets these three crops, their impact on this system is unclear. This study aims to investigate the preference and performance of D. platura in Three Sisters crops. Previous works showed increased fly infestation levels for squash and bean crops, with corn being the least affected. However, in past works, these crops were planted separately. Our results contradict previous findings, as their oviposition, statistically, is the same. Furthermore, while looking at the larval performance, the larvae in corn had the lowest performance. This could be due to the hardness of the seeds, where corn has the toughest seed coat, making it difficult for the larvae to consume. Looking at stand loss, the crops all appear to have the same losses, which can indicate that there is no individual crop that is more at risk.