Agronomic performance of the ‘Pera’ orange grafted onto nine rootstocks under the conditions of Rio Branco, Acre, Brazil

Abstract

Brazil is the world's largest sweet orange producer, but production in the state of Acre is small and does not meet the local demand, despite having climatic conditions that are adequate for its cultivation. The objective of this study was to evaluate the behavior of the 'Pera' orange using different rootstocks under the edaphoclimatic conditions of Rio Branco, Acre, Brazil. We grafted the scion of the 'Pera' orange onto nine citrus rootstocks: 'Cleopatra' mandarin, TSKFL x CTTR-013, LVK x LCR-038, TSKC x CTQT 1439-004, LVK x LVA-009, 'Indio'citrandarin, 'Santa Cruz Rangpur' lime, TSKFL x CTC-25-002, and TSKC x CTSW-038. The experiment was organized in a random block design with three replicates and two plants per parcel. The following characteristics were evaluated: compatibility between scion and rootstocks, tolerance to drought, production and fruit quality. There was an effect of the rootstocks on the behavior of the 'Pera' variety. The 'Santa Cruz Rangpur' lime, 'Indio' citrandarin, and the hybrid LVK x LCR-038 rootstocks presented the best performance of the 'Pera' orange. Therefore, they constitute an alternative to the 'Rangpur' lime and may be incorporated into the current 'Pera' orange production system of the region.

Leaf proline accumulation and fruit yield of ‘Pera’ sweet orange trees under natural water stress

“…Despite reports of abnormal graft union of 'Pera' with Cleopatra mandarin (Moraes et al 2011) and trifoliate hybrids (Carvalho et al 2018), no visual incompatibility symptoms were found in any of the evaluated scion/rootstocks combinations. Rodrigues et al (2019) also did not find symptoms in 'Pera' trees onto 'Indio' citrandarin and Schinor et al (2013) verified typical symptoms of incompatibility only in 'Pera' trees grafted onto two of the 42 evaluated hybrids 'Sunki' mandarin × trifoliate. According to Pompeu Junior and Blumer (2019), however, the incompatibility is not always readily expressed, which implies the need for a greater number of seasons of observations to reach definitive conclusions.…”

Substandard and Semi-Dwarfing Citrus Rootstocks for More Intensive, Higher-Density, and Sustainable Plantation Systems

“…On the other hand, the rootstock/scion ratio was lower (and closer to 1.00) on CL (1.17) and MP (1.28). Likewise, a good affinity in different citrus cultivars has also been found on MP [37] or CL [33,36].…”

“…Many studies have reported the effect of citrus rootstocks on tree growth [11,[32][33][34]. In fact, substandard, semi-dwarfing, and dwarfing citrus rootstocks are known [35].…”

“…Thus, more intensive and higher-density 'Lane Late' navel orange plantations could be established by adjusting the tree spacing to the tree size induced by each citrus rootstock, which in our case, would result in more than 540 trees ha −1 on FA13, FA41, and CL without needing to force the tree size by pruning. Other authors [33] have remarked an interest in considering the citrus tree growth induced by rootstocks in order to reduce the gap between trees and crop lines as much as possible, provided it does not affect productivity and fruit quality.…”

Citrus orchards under formation evaluated by UAV-Based RGB Imagery

“…Field evaluations occurred on 14 and 15 May 2020 to measure the following plant biometric attributes (ground truth): height (hp), measuring the distance (perpendicular) from the highest leaf to the plant root collar, ground level; and crown diameter, in the same direction (Dl), perpendicular to the row (Dr), both obtained using a millimeter tape measure (positioned at half of the height of the plant under evaluation). The plant volume was then estimated according to the formula presented by Rodrigues et al (2019), Eq. ( 1):…”