Combined application of plant regulators in young fruits modifies biometric characteristics and germination of atemoeira seeds cv. 'Thomson' (Atena Editora)

Abstract

The present work aims to analyze the effects of the application of plant regulators during fruit development on the biometric characteristics and germination of atemoya seeds (Annona cherimola Mill. x Annona squamosa L.) cv 'Thompson'. The fruits with an average of 2 cm were treated with four concentrations of the biostimulant Stimulate ®, equal to 500, 1000, 1500, 2000 and 0 (control) mL ha -1 ai, at 14-day intervals for five months, under field conditions. After ripe fruit seeds were sown on germitest paper rolls and taken to the germination chamber where they remained in the dark, with a temperature alternating between 20°C for 8 hours and 30°C for 16 hours. For this purpose, a completely randomized experimental design was adopted, considering the treatments applied to the fruits in the field, distributed in five replications of 25 seeds each. The variables ­evaluated after the collection of the fruits were: number of seeds, fresh mass of seeds, dry mass of seeds, water content of seeds and in the germination test, it was considered: germination percentage, germination speed index and average germination time. After the germination test, it was determined: total number of seeds, number of live and dead seeds, number of dormant and dead seeds in tetrazolium. From the results, it can be seen that 1500 mL ha -1 in young fruits tends to increase the number of seeds, resulting in a lower water content. The seeds of the fruits treated with a concentration of 1000 mL ha -1, took a shorter mean time to germinate. There is a trend between germination percentages and dormant seeds. It is concluded that, under the conditions of the experiment, the combined application of plant regulators in young fruits, discreetly modifies biometric characteristics and seed germination of atemoeira cv 'Thompson'.