Performance and reaction to huanglongbing of ‘Tahiti’ acid lime grafted on citrandarins

Abstract

The 'Tahiti' acid lime (Citrus latifolia Tan.) has a great economic importance, with the state of Sao Paulo responsible for 70% of the Brazilian crop. There are no reports in the literature of the use of citrandarins (hybrids of mandarins with Poncirus trifoliata) as rootstock (RT) for 'Tahiti'. The RTs were not initially part of the discussion related to huanglongbing (HLB or greening) disease studies, one of the main diseases of citrus; however, there is evidence that citrus plants on different RT may differ in incidence or tolerance to the disease. This work aimed to evaluate the reaction of 'Tahiti' lime grafted onto 'Rangpur' lime (RL), 'Sunki' mandarin, Poncirus trifoliata 'Flying Dragon' (FD) and thirteen citrandarins (TS×PT) to the bacterium Candidatus Liberibacter asiaticus, causal agent of HLB, and its vegetative and productive performance. The experiment was conducted at the Paulista Agency of Agribusiness Technology, located in Pindorama, Brazil, in the years 2016 and 2017. The biometrics of the plants, the monthly production of the fruits and the detection and quantification of the bacteria by real-time quantitative PCR were carried out. 'Tahiti' grafted onto citrandarin TS×PT 14 presented a positive result for HLB and no visual symptoms were observed in the field. The most prominent RT in relation to the accumulated production was RL, followed by citrandarins TS×PT 10 and TS×PT 121. The lowest and highest canopy volume were observed for citrandarin TS×PT 14 and RL, respectively. The evaluations made in the sixteen rootstocks allowed to verify that citrandarin TS×PT 14 presents a possible tolerance to HLB, however, its canopy volume and production are low. It can be considered as a dwarfing rootstock for 'Tahiti' lime.