Growth, yield and quality of potato tubers (Solanum tuberosum L.) due to the aplication of plant regulators

Author(s)

Jesion Geibel da Silva Nunes

• Document type: Master's Dissertation
• Institution: Universidade Estadual Paulista (Unesp)
• Defense date: 2017-07-20
• Advisor: Adalton Mazetti Fernandes; Rogério Peres Soratto

Abstract

Potato yield depends on the plant's ability to synthesize carbohydrates in the leaves and mobilize them for growing tubers. Thus, excessive leaf growth in the late stages of the crop cycle can negatively affect tuber yield. Under conditions favorable to shoot growth, the use of retarders or plant growth regulators may be an alternative to improve crop yield by reducing plant size and increasing dry matter (DM) the growing tubers. Thus, the aim of this work was evaluate the effect of plant growth regulators mepiquat chloride, chlormequat chloride, prohexadione calcium and placobutrazol on the growth, yield and quality of potato tubers of Agata and Mondial cultivars. Two independent experiments were conducted, one with the cultivar Agata and the other with the cultivar Mondial. Both experiments were installed in a randomized complete block design in the 4x5+1 factorial scheme, with four replications. The treatments were represented by four plant regulators (mepiquat chloride, chlormequat chloride, paclobutrazol and proexadione calcium), applied at the rates of 25, 50, 100, 200 and 400 g ha-1 of i.a., in addition to the control treatment (without the application of plant growth regulator). In the Agata cultivar, all growth regulators had a similar effect on the growth and yield characteristics of tubers, but the prohexadione calcium regulator decreased the postharvest quality of the tubers. In the Mondial cultivar the growth regulator paclobutrazol was more efficient in reducing the vegetative growth of the plants and maintaining the postharvest quality of the tubers. In both cultivars the greatest effects on growth and commercial yield of tubers occurred between the rates of 50 and 100 g ha-1 of i.a.. In the cultivar Agata the rates of growth regulators reduced the commercial yield of tubers, but in the cultivar Mondial the commercial yield of tubers increased with the application of the doses of growth regulators. (AU)

• FAPESP's process: 15/22885-0 - Plant growth, yield and quality of tubers of potato crop (Solanum tuberosum L.) in response to application of plant growth regulators
• Grantee: Jesion Geibel da Silva Nunes
• Support Opportunities: Scholarships in Brazil - Master