Growth of sugarcane cultivar na 56-79 originated from stalks treated with ethephon

Abstract

Ethephon was applied on the dosages 0, 2 e 3 liters per hectare on sugarcane cultivar NA 56-79, 3l days before harvesting. At harvesting time, the following parameters were evaluated: infestation by the Diatraea saccharalis; damaged, swelled and emerged buds; stalks lenght, top lenght; number of buds per stalk and the cane quality. The setts obtained from the stalks were planted at three differents densities: normal, crossed and doubles setts. Initially, the number of sprouts was collected weekly and later monthly. The other parameter, stalk lenght, was obtained under monthly intervals. The stalks number and the production were taken at the 1st, 2nd and 3rd year's growth. The results showed that the ethephon's application on 2 l/ha, before harvesting, increased the number of buds and the stalks lenght. The dosage 3 l/ha reduced the amount of fibers on the apical region of the sugarcane. Increasing of the bud emergency velocity was observed on the dosage 21/ha, before tillering. With reference to planting density, doubles setts showed emergency velocity greater than crossed setts. In turn, the crossed setts proved emergency velocidy greater than normal setts. The growth, tillering and the three years productions of the sugarcane coming from setts of the stalks treated or not with ethephon showed no significative differences.