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

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.

Biostimulant Application Improves Yield Parameters and Accentuates Fruit Color of Annurca Apples

“…The total soluble solids content (Table 3) showed similar values between the control, LG, and MA, while PEP reported a lower value of about 5.35% compared to the other treatments. Similar results have also been observed by Bradshaw et al [31] and by De Sousa et al [32], in which ANE (Ascophyllum nodosum extracts) treatment had no effect on fruit firmness, starch index at harvest, and soluble solids concentration. Whereas, in agreement with Robert and von Loeska [33], TSS showed an increase of 9.9% from the harvest to +120 days of cold storage, while in contrast to TSS, a reduction in titratable acidity of 49.3% was registered.…”

Vegetative growth, yield, and fruit quality of guava (Psidium guajava L.) cv. Maamoura as affected by some biostimulants

“…In addition, treating orange with SEs increased the maturity index and yield, while it decreased the fruit drop (Arioli et al 2015;Gomathi, et al 2017). Spraying SE on apple (Malus domestica L.) increased fruit set and fruit yield (Soppelsa et al 2018;Valencia et al 2018;de Sousa et al 2019). The application of SEs at 0, 2, 4, and 8 gL -1 on 'Albion' strawberry cultivar via fertigation system increased the number of flowers per plant, and the yield, compared with the control, was also increased (Al-Shatri et al 2020).…”

“…SE could be applied in low quantities as soil or foliar spraying, and it can improve the resistance to insect and pathogen attack and abiotic stress such as drought, frost, salinity, and high or low temperature (Khan et al 2009;Craigie 2011;Battacharyya et al 2015;Elansary et al 2016). Because of the high content of SE from nutrients, hormones, amino acids, vitamins, and antioxidants, it can be defined as a stimulant, which can increase the cell division in plants (Prasad et al 2010;Colavita et al 2011). de Sousa et al (2019 reported that spraying SE on 'Gala' apple cultivars at 0.1, 0.2, 0.3, 0.4, and 0.6% increased the percentage of fruit set, number, weight, and length of fruits compared with control, and the prior treatment was 0.3%.…”