Submitted to: Pan Pacific Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 15, 2001
Publication Date: March 1, 2002
Citation: Landolt, P.J. 2002. Survival and development of Lacanobia subjuncta (Lepidoptera: Noctuidae) larvae on common weeds and crop plants of eastern Washington state. Pan Pacific Entomology. 78:1-6. Interpretive Summary: New approaches and methods are needed to manage populations of moth pests of apple, including Lacanobia subjuncta, without using broad spectrum pesticides. In order to devise management strategies, it is important to understand how pest populations increase above economically damaging levels. Scientists at the USDA-ARS Yakima Agricultural Research Laboratory are studying the biology and behavior of L. subjuncta, including the host range of the larvae. It was found that this insect can feed and develop on a wide range of plant species, including a number of weeds common in apple orchards and on other crops commonly grown in eastern Washington. This information suggests that high populations of L. subjuncta found in apple orchards may originate in part from areas of weeds and other crops, in addition to the apple trees. Management practices for this insect on apple will need then to include methods to control immigrating moths coming into apple orchards.
Technical Abstract: Ten common weed species, four tree fruit crops and four row crops were evaluated as hosts for larvae of Lacanobia subjuncta Grote & Robinson, a noctuid moth pests of apple in eastern Washington. A separate comparative evaluation was made of the suitability of five varieties of apple as hosts for L. subjuncta larvae. Development was completed, from neonate larva to adult, on nine of ten weed species and seven of eight crops tested, indicating a broad potential host range for this insect. High rates of survival to adult, short developmental times, and large pupal weights were noteworthy on the weeds bindweed, dandelion, and mallow, and on potato. In the comparison of apple varieties, highest rate of survival to adult was with Red Delicious, greatest pupal weights were with Red Delicious, Gala, and Fuji, and shortest development times were with Gala and Granny Smith. Strong seasonal variation (May versus July) was indicated in the quality of apple foliage as food for L. subjuncta larvae.