Fruit set and yield of apple trees cv. Gala treated with seaweed extract of ascophyllum nodosum and thidiazuron

Ricardo Antonio Ayub,Anelise Marques De Sousa,Thayna Viencz,Renato Vasconcelos Botelho

doi:10.1590/0100-29452019072

Abstract

Abstract The low effective fruiting is one of the biggest problems of apples’ production in Brazil and its main cause involves the process of pollination. The objective was to evaluate the fruit set and production of apple trees cv. Gala treated with extract of seaweed Ascophyllum nodosum and thidiazuron. The experiment was carried out during two cycles (2015/2016 and 2016/2017) in Porto Amazonas, State of Paraná, Brazil, with apple trees cv. Gala. The following treatments were applied at full bloom: thidiazuron at 10 and 15 mg L-1, Ascophyllum nodosum seaweed extract (Algamare®) at concentrations of 0.1, 0.2, 0.3, 0.4 and 0.6%. No treated plants were used as control. It was evaluated: fruit set, number of fruits, fruit weight, yield per plant, number of seeds per fruit, length and diameter of fruit, length/diameter ratio (L/D), titratable acidity, soluble solids, firmness and growth of shoots. The algae extract presented similar effects of thidiazuron in apple trees, promoting, in at least one of the cycles, the increase in fruit set, number of fruits, weight and length of fruits without changing their maturation. The application of Algamare® at 0.3% was the most effective treatment for yield improvement in ‘Gala’ apples.

Highlights

The southern region of Brazil stands out for the cultivation of deciduous fruit plants, especially apple trees, which, in the last decades, has shown a remarkable development, allowing Brazil to move from importing country to exporter
The main cultivars produced in Brazil are Gala, Fuji and their clones, which account for approximately 95% of the national apples production (ABPM, 2017)
The low effective fruiting is one of the biggest problems related to the production of apples in Brazil and has as main cause the limitations that involve the process of pollination

Summary

Introduction

The southern region of Brazil stands out for the cultivation of deciduous fruit plants, especially apple trees, which, in the last decades, has shown a remarkable development, allowing Brazil to move from importing country to exporter. The main cultivars produced in Brazil are Gala, Fuji and their clones, which account for approximately 95% of the national apples production (ABPM, 2017). Aiming to attend the growing demand for apple consumption, new technologies that improve the productive aspects are necessaries. The low effective fruiting is one of the biggest problems related to the production of apples in Brazil and has as main cause the limitations that involve the process of pollination. The absence of fertilization of the ovules in apple flowers results in a smaller number of fruits bearing per plant, deformed and smaller fruits and, a reduction in productivity and profitability of the orchard

Objectives

Methods

Results

Conclusion