Cultivar-specific traits can impact crop resistance and tolerance to pests through multiple mechanisms such as growth rate, nutrients, and presence of direct and induced defense mechanisms. In Louisiana, sugarcane is of the most economically important crops, with new cultivars developed and released annually. Cultivars within a few years of release to the industry are assessed for resistance to one of the primary insect pests in the region – the sugarcane borer (Diatraea saccharalis) or SCB. We leveraged the long-term data collected by this historic breeding program as well as several field studies (2-3 crop years) to evaluate changes in SCB damage based on presence of prior damage, cultivars, specific traits, and crop year. We found that within a crop year, the probability of SCB damage increased with prior damage. The overall risk of damage changed with cultivar and interacted with crop year; but the previous damage effect did not match known resistance patterns even though it varied with cultivar. The probability of damage changed from the plant cane to the first ratoon, but damage accrued in a prior crop year did not impact the probability of SCB damage in future years. Overall, we found that SCB management early within a crop year is critical, but the importance of early prevention differs with cultivar, the underlying mechanisms of which need to be assessed further. Moving forward to these results, we are looking to jointly evaluate traits underlying apparently related aspects like cold tolerance with SCB resistance.
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