Combined Treatment with Gibberellins and Jasmonic Acid Derivative Prohydrojasmon Increases Potato Yield

Abstract

The yield components of potato are number of tubers and average tuber weight, and these yield components need to be increased to improve yield. Gibberellin treatment of seed potatoes prior to planting is known to increase the number of tubers at harvest time, but does not increase yield because the average tuber weight is reduced. On the other hand, jasmonic acid is known to promote tuber formation and enlargement. Therefore, the present study investigated whether treatment with prohydrojasmon, a derivative of jasmonic acid, in addition to gibberellin treatment would increase the yield of potato. Gibberellin treatment was done by soaking seed tubers before planting, while prohydrojasmon treatment was done by foliar spray at 100 ppm to 200 ppm at the tuber initiation stage. The results showed that the combined gibberellin and prohydrojasmon treatment increased yield to the same extent as the top-dressing treatments. In particular, the yield increase in the combined gibberellin and prohydrojasmon treatment was more stable than that in the prohydrojasmon alone treatment or the combined gibberellin and top-dressing treatment, suggesting a synergistic effect of gibberellin and prohydrojasmon on tuber growth. The gibberellin and prohydrojasmon treatment also resulted in less reduction in starch content loss than the top-dressing treatment. In summary, the combined gibberellin and prohydrojasmon treatment could be an alternative to chemical fertilizers for increasing potato yield.