Resistance Level of Sweet Potato Clones to Sweet Potato Weevil (Cylas formicarius)

Abstract

In Indonesia, the yield losses of local sweet potato variety due to sweet potato weevil (SPW) caused by the Cylas formicarius insect could reach 100%. The most useful C. formicarius control technology is to use the resistant varieties. This study aims to evaluate the level of resistance of six sweet potato clones to SPW. The field test was conducted in dry season (May - October 2024) in two locations in Lumajang Regency, East Java Province namely Karanganom Village, Pasrujambe District, and  Sarikemuning Village, Senduro District.  Randomized Block Design with four was used replications. Each sweet potato genotype was planted on a plot of 5 m x 5 m, plant distance of 100 cm x 25 cm (1 steck per hole). The clones were tested in the field and in the laboratory. Observation of tuber borer pest attacks on tested clones Laboratory resistant aims to prove and ensure the tolerance level of candidate sweet potato varieties to tuber borer pests. The sweet potato harvest from the field is then cleaned from the soil using water, then healthy tubers (free from C. formicarius) with uniform sizes are selected. Furthermore, the tubers are put into plastic mylar with a height of 20 cm and a diameter of 8 cm. The resistance test method used were choice and without (no)-choice. Results of the trials showed that sweet potato Gatotkoco has a level of resistance to sweet potato weevil equivalent to the check variety Sari which is classified as a resistant, while Bima Pasru has a level of resistance equivalent to the check variety Beta 2 which is classified as an intermediate resistant. These two local varieties of Lumajang (Gatotkoco and Bima Pasru) could be developed to overcome the problem of sweet potato weevil in the field.