Impact of diseases and pests on premature fruit drop in sweet orange orchards in São Paulo state citrus belt, Brazil

Abstract

Background Despite technical improvements in the citrus chain and leadership in orange production achieved in the past decades, premature fruit drop remains a major component of crop loss in São Paulo state citrus belt, the largest sweet orange production area in the world. The present study aimed to determine, during five consecutive seasons, the impact of the diseases and pests on premature fruit drop in the orange belt. Results Fruit drop due to the main diseases and pests averaged approximately 11.0%, which corresponded to approximately 63% of the annual fruit drop. The average fruit drop rate due to fruit borer and fruit flies combined was 4.0%, Huanglongbing (HLB) 3.3%, black spot 2.6%, leprosis 1.0% and citrus canker 0.3%. The average amount of fruit drop (million 40.8 kg boxes) and value of crop losses (million US$ dollars), in five seasons, were 12.7 and 66.2 for fruit borer/fruit flies, 11.0 and 57.9 for HLB, 8.1 and 42.2 for black spot, 3.1 and 15.6 for leprosis, and 0.9 and 4.9 for citrus canker, respectively. Conclusion Fruit borer and fruit flies (combined), HLB, black spot, leprosis and citrus canker are, in this order, the main diseases and pests in the orange belt of São Paulo state. All of these causes significantly increased the overall fruit drop rate in the evaluated seasons. The results will contribute to the development of the Brazilian citrus industry, while showing to other citrus‐growing regions the potential that diseases and pests have to jeopardize production. © 2022 Society of Chemical Industry.

Citrus Bright Spot Virus: A New Dichorhavirus, Transmitted by Brevipalpus azores, Causing Citrus Leprosis Disease in Brazil

“…CL is considered the main viral disease that affects citrus production in Brazil [ 17 , 18 ]. The disease can be caused by viruses of at least five species within the genera Dichorhavirus and Cilevirus [ 19 ], but commercial orchards in Brazil are almost exclusively affected by citrus leprosis virus C ( Cilevirus leprosis , genus Cilevirus , family Kitaviridae ) [ 20 ].…”

“…The control of Brevipalpus mites in orchards of the Southeastern region of Brazil, the main citrus-producing area of the country, represents almost 5% of the management cost of the orchards, i.e., approximately US $54 million per year [ 17 ]. In that region, premature fruit drop associated with CL was assessed in 5.82 million boxes in the 2020/2021 harvest ( ) (accessed on 20 July 2022) [ 17 , 18 , 22 ]. The northeast and southern regions represent 10% and 8% of citrus national production, respectively ( ) (accessed on 20 July 2022), but the epidemiology of CL and losses associated with this disease remain poorly known [ 23 ].…”

Nematode–citrus plant interactions: host preference, damage rate and molecular characterization of Citrus root nematode Tylenchulus semipenetrans

“…are economically important crops. Many pests and diseases (Moreira et al 2022), including plant parasitic nematodes (PPN) (Philis 1989;Abd-Elgawad et al 2016), cause significant crop losses in citrus. Among PPN, the citrus root nematode, Tylenchulus semipenetrans (Cobb 1913) (Tylenchida: Tylenchulidae), genus Tylenchulus, is detrimental to citrus plants.…”

Insight into resistance to ‘Candidatus Liberibacter asiaticus,’ associated with Huanglongbing, in Oceanian citrus genotypes

“…Fruits are smaller and misshapen while the juice is highly acidic and poor in soluble solids (Bassanezi et al, 2009). Symptomatic leaves and fruits drop prematurely (Moreira et al, 2022). Leaf symptoms can be confusing, especially at the early stages of infection, and, thus, not always can be used for diagnosis purposes (Gottwald et al, 2007).…”