Estimativa da necessidade de frio e calor do pessegueiro ‘Cascata 587’ com uso de testes biológicos

Abstract

The production of temperate fruit trees in mild climates is dependent on the continuous criation of new cultivars with reduced chilling requirements and reliable methods to estimate them. Thus, it is necessary to study more accurate ways to estimate endodormancy release in peach tree, than the phenological dates of flowering and leafing. This work aims to study the dynamics of dormancy in peach tree genotype Cascata 587 in field condition, by Tabuenca's test and 'Single-node cutting' test. Tabuenca's test consists in measuring the mass of buds before and after forcing 7 days at 25 °C, when observed difference between the samples, it is considered that the meristem was able to absorb water and soluble solids marking the end of endodormancy. The 'single-node cuttings' test is performed under forcing at 25 °C and 16 hour photoperiod measurand is the average time to budbreak (TMB). The two methods together can indicate the end of endodormancy and improve the estimation of chilling and heat requirements of the cultivar. The Tabuenca and singlenode cutting tests can estimate chilling igual or less than any of the models based on phenological with smallest coefficient of variation.