Potato Tuherworm Damage to Potatoes Under Different Irrigation and Cultural Practices

Potatoes grown under furrow irrigation sustained over 58 times greater infestation by Phthorimaea operculella (Zeller) and 3 times more green tubers than potatoes grown under sprinkler irrigation even though foliage tuberworm populations, soil type, and soil moisture levels were similar. Water usage on a per ha basis was more efficient under sprinkler irrigation. Under furrow irrigation, hilling the rows 4 times significantly reduced the percentages of greenheads, infested whites, and total infestation over those rows hilled twice. The method of vine removal affected the level of tuber infestation in rows hilled twice but not in rows hilled 4 times. Under frequent sprinkler irrigation potato tuberworm damage was low and not significantly affected by cultural practices. Soil cracking was more extensive under furrow than under sprinkler irrigation, and infestation was significantly correlated with the depth of soil cracks regardless of hilling practices.