ABSTRACT:

Root-knot nematode is one of the most important phytosanitary problems for Conilon coffee, as it reduces productivity and is difficult to handle. We aimed at studying the infectivity and damage caused by M. incognita race 1 in the “Jequitibá Incaper 8122” intermediate maturity coffee variety. The experiment was conducted in a greenhouse, in completely randomized design, with five replicates. The clones composing the variety “Jequitibá Incaper 8122” were inoculated with 2,000 eggs + second-stage juveniles of M. incognita race 1. Uninoculated plants were the control. Evaluations were performed 180 days after inoculation, considering the plant height (H), stem diameter (SD), number of leaves (NOL), leaf area (LA), number of plagiotropic branches (NPB), number of nodes (NN), chlorophyll content (CHLO), shoot dry matter (SDM), root fresh matter (RFM), final population (FNP), and reproduction factor (NRF). The nematode reduced NOL in clones 208 and 209, NRF in clones 201, 203, 207 and 208, NN in clones 203, 207, 208 and 209, CHLO in clones 201, 204, 206, 207 and 209, SDM in clones 201, 203, 204 and 205 and RFM in clones 205 and 207. M. incognita race 1 FNP and NRF were larger in clones 208, 201, 207 and 203. Clone 202 had FNP and NRF equal to zero, being immune to the nematode. Clone 206 presented the lowest NRF value among clones parasitized by M. incognita.

KEYWORDS:
Conilon coffee; root-knot nematode; resistance; damage

RESUMO:

O nematoide-das-galhas é um dos mais importantes problemas fitossanitários para o cafeeiro conilon, por reduzir a produtividade e ser de difícil manejo. Objetivou-se estudar a infectividade e os danos causados por M. incognita raça 1 na variedade de café conilon de maturação intermediária “Jequitibá Incaper 8122”. O experimento foi conduzido em casa de vegetação, em DIC, com cinco repetições. Os clones que compõem a variedade “Jequitibá Incaper 8122” foram inoculados com 2.000 ovos + juvenis de segundo estádio de M. incognita raça 1. Plantas não inoculadas constituíram a testemunha. As avaliações foram realizadas 180 dias após a inoculação, sendo avaliados: altura da planta (ALT), diâmetro do caule (DCA), número de folhas (NFO), área foliar (AFO), número de ramos plagiotrópicos (NRP), número de nós (NN), teor de clorofila (CLO), massa seca da parte aérea (MSA), matéria fresca da raiz (MFR), população final (PFN) e fator de reprodução (FRE). O nematoide reduziu o NFO nos clones 208 e 209, NRP nos clones 201, 203, 207 e 208, NN nos clones 203, 207, 208 e 209, CLO nos clones 201, 204, 206, 207 e 209, MSA nos clones 201, 203, 204 e 205 e MFR nos clones 205 e 207. PFN e FRE de M. incognita raça 1 foram maiores nos clones 208, 201, 207 e 203; o clone 202 teve a PFN e a FRE igual a zero, apresentando-se imune ao nematoide. O clone 206 apresentou o menor valor de FRE entre os clones parasitados por M. incognita.

PALAVRAS-CHAVE:
café Conilon; nematoide-das-galhas; resistência; danos

INTRODUCTION

Brazil is the world's largest producer and exporter of coffee (MAPA, 2017MINISTÉRIO DA AGRICULTURA, PECUÁRIA E ABASTECIMENTO (MAPA). Projeções do agronegócio Brasil 2016/17 a 2026/27. Brasília: MAPA, 2017.). The state of Espírito Santo is the first in the ranking of Conilon coffee production (Coffea canephora Pierre ex A. Fronier) (CONAB, 2018COMPANHIA NACIONAL DE ABASTECIMENTO (CONAB). Safra 2018 - Primeiro levantamento, v.5, n.1, 72p, 2018. Available from: https://www.conab.gov.br/info-agro/safras/graos/boletim-da-safra-de-graos/item/download/20861_fb79e3ca2b3184543c580cd4a4aa402b. Access on: Jan. 20 2019.
https://www.conab.gov.br/info-agro/safra... ). Conilon coffee is the main raw material for the industry of soluble coffee and blends. The demand and consumption of these types of industrialized coffee have been increasing worldwide (KALSCHNE et al., 2018KALSCHNE, D.L.; VIEGAS, M.C.; DE CONTI, A.J; CORSO, M.P.; BENASSI, M.T. Steam pressure treatment of defective Coffea canephora beans improves the volatile profile and sensory acceptance of roasted coffee blends. Food Research International, v.105, n.3, p.393-402, 2018. https://doi.org/10.1016/j.foodres.2017.11.017
https://doi.org/10.1016/j.foodres.2017.1... ).

The Conilon coffee variety “Jequitibá Incaper 8122” consists of nine clones and was developed in the state of Espírito Santo by the Instituto Capixaba de Assistência Técnica e Extensão Rural (Incaper) (DOPES, 2013DIÁRIO OFICIAL DOS PODERES DO ESTADO (DOPES). Espírito Santo lança novas variedades clonais de café Conilon. Vitória, Espírito Santo, segunda-feira, 17 jun. 2013. Available from: https://www.folhavitoria.com.br/geral/blogs/midiaemercado/2013/07/04/cafe-conilon-em-novas-variedades/. Access on: Sep. 20 2014.
https://www.folhavitoria.com.br/geral/bl... ; FERRÃO et al., 2015FERRÃO, R.G.; FERRÃO, M.A.G.; FONSECA, A.F.A.; VOLPI, P.S.; VERDIN FILHO, A.C.; MAURI, A.; LANI, J.A. ‘Diamante ES 8112’, ‘ES 8122 – Jequitibá’ and ‘Centenária ES 8132: new clonal varieties of Coffea canephora, conilon variety with high beverage quality. In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 9., 2015, Curitiba. Consórcio pesquisa café: oportunidades e novos desafios. Brasília, DF: Embrapa Café, 2015.). The use of these varieties has helped the state production to increase 300% in the last 20 years (FERRÃO et al., 2013FERRÃO, R.G.; FERRÃO, M.A.G.; FONSECA, A.F.A.; VERDIN FILHO, A.C.; LANI, J.A.; TÓFFANO, J.L.; TRAGINO, P.H.; BRAVIM, A.J.B.; MORELI, A. P. Jequitibá Incaper 8122 – Nova variedade clonal de café conilon de maturação intermediária para o Espírito Santo. Vitória: INCAPER, 2013.).

Phytonematodes of the genus Meloidogyne represent a serious threat to coffee plantations throughout Brazil (PAULI et al., 2013PAULI, B.; SALGADO, S.M.L; BOTELHO, T.T.; SOUZA, S.R.; TASSONE, G.A.; SOUZA, J.E.N.; LIMA, I.M. Comportamento inicial de clones de conilon “vitória Incaper 8142” em área infestada por Meloidogyne paranaensis no sudoeste de Minas Gerais. In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 8., Salvador, Bahia, 2013. Anais… Salvador: Consórcio Pesquisa Café, 2013.; BARROS et al., 2014BARROS, A.F.; OLIVEIRA, R.D.L.; LIMA, I.M.; COUTINHO, R.R.; FERREIRA, A.O.; COSTA, A. Root-knot nematodes, a growing problem for Conilon coffee in Espírito Santo state, Brazil. Crop Protection, v.55, p.74-79, 2014. https://doi.org/10.1016/j.cropro.2013.10.004
https://doi.org/10.1016/j.cropro.2013.10... ; CONTARATO et al., 2014CONTARATO, C.; TOMAZ, M.A.; ALVES, F.R.; SOBREIRA, F.M.; JESUS JUNIOR, W.C; RABELLO, L.K.C.; FERRÃO, M.A.G.; FERRÃO, R.G. Reaction of variedade coffee ‘Vitória INCAPER 8142’ of conillon to parasitism of Meloidogyne exigua. Idesia, v.32, n.1, p.93-97, 2014. https://doi.org/10.4067/S0718-34292014000100011
https://doi.org/10.4067/S0718-3429201400... ; BARROS et al., 2014BARROS, A.F.; OLIVEIRA, R.D.L.; LIMA, I.M.; COUTINHO, R.R.; FERREIRA, A.O.; COSTA, A. Root-knot nematodes, a growing problem for Conilon coffee in Espírito Santo state, Brazil. Crop Protection, v.55, p.74-79, 2014. https://doi.org/10.1016/j.cropro.2013.10.004
https://doi.org/10.1016/j.cropro.2013.10... ). The susceptibility of C. canephora to Meloidogyne incognita parasitism was confirmed by CARNEIRO et al. (2009)CARNEIRO, R.M.D.G.; COSTA, S.B.; SOUZA, F.R.; SANTOS, D.F.; ALMEIDA, M.R.A.; SANTOS, M.F.A.; SIQUEIRA, K.M.S.; TIGANO, M.S.; FONSECA, A.F.A. Reação de cafeeiros ‘conilon’ a diferentes populações de Meloidogyne spp. In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 6., 2009. Vitória, 2009..

Considering the worldwide importance of Conilon coffee for the coffee industry and the occurrence of Meloidogyne nematodes in the producing regions, it is extremely important to know the patho-system involving Conilon coffee versus Meloidogyne incognita, especially regarding the behavior of new genetic materials against the nematode.

We aimed to evaluate the infectivity and to quantify the damage caused by M. incognita race 1 to the nine intermediate maturity clones of Conilon coffee variety “Jequitibá Incaper 8122”.

MATERIAL AND METHODS

The experiment was carried out in a greenhouse at a completely randomized design (CRD), with five replicates. The nine clones that compose the variety “Jequitibá Incaper 8122” (clones 201, 202, 203, 204, 205, 206, 207, 208 and 209) were inoculated with 2,000 eggs + juveniles of second stage (J2) of M. incognita race 1. Uninoculated plants constituted the control sampling.

Seedlings of the nine clones of the “Jequitibá Incaper 8122” variety were originated from an accredited nursery and with proven phytosanitary origin. They were transplanted with five to seven pairs of definitive leaves to 20-L pots containing dystrophic Red-Yellow Latosol; sieved in a 2 mm sieve and treated with previous solarization for 30 days. Planting fertilization and coverage recommended by NOVAIS et al. (1991)NOVAIS, R.F.; NEVES, J.C.L.; BARROS, N.F. Ensaio em ambiente controlado. In: OLIVEIRA, A. J. de; GARRIDO, W.E.; ARAUJO, J.D.; LOURENÇO S. Métodos de pesquisa em ambiente controlado. Brasília: Embrapa-SEA, 1991. were carried out. Irrigation was performed in such a way that the soil moisture reached 80% of the field capacity.

The pure inoculum of M. incognita race 1 was obtained from coffee roots of clone V2 of the “Vitória” variety infected by M. incognita race 1, which was kept in a greenhouse. The nematode was previously identified by isoenzyme electrophoresis (CARNEIRO; MAZAFFERA, 2001CARNEIRO, R.G.; MAZAFFERA, P. Relação fonte-dreno e absorção e transporte de minerais em plantas infectadas por nematoides. In: SILVA, J.F.V. Relações parasito-hospedeiro nas meloidoginoses da soja. Londrina: Embrapa Soja, 2001. p.630-693.). The substrate used for coffee cultivation was composed of soil and sand. The soil was manually mixed with sand, in the proportion of 1:1 (V:V), and sterilized in an autoclave at 120°C for 20 minutes. This this procedure was repeated for three consecutive days.

The nematodes were extracted using the technique of HUSSEY; BARKER (1973)HUSSEY, R.S.; BARKER, K.R. A comparison of methods of collecting inocula of Meloidogyne spp., including a new technique. Plant Disease Reporter, v.57, p.1025-1028, 1973. modified by BONETI; FERRAZ (1981)BONETI, J.I.S.; FERRAZ, S. Modificações do método de Hussey e Barker para extração de ovos de Meloidogyne exigua em raízes de cafeeiro. Fitopatologia Brasileira, Brasília, v.6, n.3, p.553, 1981., and the quantification of the inoculum was performed in a Peters chamber under an optical microscope.

Fifteen days after transplanting, an aqueous suspension containing inoculum was deposited in four holes made in the rhizosphere region of the coffee seedlings and, after inoculation, the holes were covered with washed sterile sand.

Evaluations were carried out 180 days after inoculation. The variables evaluated were: plant height (H), number of leaves (NOL), stem diameter (SD), number of plagiotropic branches (NPB), number of nodes (NN), leaf area (LA), shoot dry matter (SDM), fresh matter of the root system per plant (RFM), final nematode population (FNP), reproduction factor (NRF), and chlorophyll content (CHLO).

To assess the FNP, the root system was carefully washed and weighed on an electronic scale, obtaining the RFM. For the quantification of FNP made up of eggs + J2, the methodology proposed by HUSSEY; BARKER (1973)HUSSEY, R.S.; BARKER, K.R. A comparison of methods of collecting inocula of Meloidogyne spp., including a new technique. Plant Disease Reporter, v.57, p.1025-1028, 1973., modified by BONETI; FERRAZ (1981)BONETI, J.I.S.; FERRAZ, S. Modificações do método de Hussey e Barker para extração de ovos de Meloidogyne exigua em raízes de cafeeiro. Fitopatologia Brasileira, Brasília, v.6, n.3, p.553, 1981., was used. The NRF was obtained by the quotient of the FNP number by the initial population (Pi) used in the plant inoculation.

Using a millimeter ruler, the length and the greatest width of each leaf were measured in millimeters, and the product between length and width was also calculated. Thus, all leaves of each plant were measured in every evaluation period (t_x).

After converting the measurements to leaf area, according to the described procedure, the total LA of each plant was calculated in every evaluation time, obtained by adding the areas of each leaf, according to the equation: LA_tx = (F1 + F2 + … + Fn), in which LA_tx is the total LA of the plant and F1, F2 … Fn, the areas of each leaf of the plant at the considered t_x time. Subsequently, the values were corrected by the equation proposed by KEMP (1960)KEMP, C.D. Methods of estimating the leaf area of grasses from linear measurements. Annals of Botany, Oxford, v.24, n.4, p.491-499, 1960. https://doi.org/10.1093/oxfordjournals.aob.a083723
https://doi.org/10.1093/oxfordjournals.a... , HUERTA; ALVIM (1962)HUERTA, S.A.; ALVIM, P.T. Índice de área foliar y su influencia en la capacidad fotosintética del cafeto. Cenicafe, Caldas, v.13, n.2, p.75-84, 1962.: ÂF = 0.667.C.L, in which ÂF is the estimate of the LA (cm²); L is the greatest length (cm); and W is the largest width (cm).

For the evaluation of the CHLO, the portable chlorophyll meter SPAD-502 (Minolta Chlorophyll Meter SPAD-502^®) was used, which, in a non-destructive way, provided the accurate reading of the CC (ng/cm²). Two measurements were taken in each evaluation (one in each side of the central rib) of each leaf of the same physiological age, using the average between the two for the purpose of analysis.

Data were analyzed using the statistical software “GENES” (CRUZ, 2006CRUZ, C.D. Programa GENES. Viçosa: UFV, 2006. 382p.) for homogeneity analysis of variance, and the means were compared by the Scott-Knott cluster test at a 5% probability.

RESULTS

The nematode reduced NOL in clones 208 and 209, NRP in clones 201, 203, 207 and 208, NN in clones 203, 207, 208 and 209, CHLO in clones 201, 204, 206, 207 and 209, SDM in clones 201, 203, 204 and 205, and RFM in clones 205 and 207 (Table 1).

There was no effect of the nematode on H, SD, and LA. The FNP and, consequently, the NRF of M. incognita race 1 were higher, respectively, in clones 208, 201, 207 and 203; clone 202 showed FNP and NRF equal to zero, being immune to the nematode (Table 2).

Clones 206, 204 and 205 showed the lowest NRF value among the clones parasitized by M. incognita (Table 2).

DISCUSSION

The clones that had the greatest number of reduced variables (201, 202, 207 and 208) were the ones that had the highest FNP and NRF, that is, larger nematode populations resulted in greater damage to plants. These damages occurred due to impaired absorption of water and nutrients in plants infected with M. incognita, which consequently affected the vegetative growth characteristics. As the root system is damaged, the growth characteristics of the plant become compromised (VAASTA et al., 1998VAASTA, P.; CASWELL-CHENB, E.P.; ZASOSKI, R.J. Effects of two endoparasitic nematodes (Pratylenchus coffeae and Meloidogyne konaensis) on ammonium and nitrate uptake by Arabica coffee (Coffea arabica L.). Applied Soil Ecology, v.10, n.1-2, p.171-178, 1998. https://doi.org/10.1016/S0929-1393(98)00037-7
https://doi.org/10.1016/S0929-1393(98)00... ).

During the infectious process and root colonization by root-knot nematodes, the pathogen demands energy for its own growth and reproduction. For Meloidogyne spp., which modify the cells that will feed them, there is hyperplasia and hypertrophy of the nutrient cells and the nutrient uptake of the plant, demanding carbon from the plant. Hence, and taking into account the spatial division between source and drain, the nematodes assume drain characteristics, that is, there is transport of organic nutrients from the aerial part to a distant location, the roots, which will nourish the nematodes (CARNEIRO; MAZAFFERA, 2001CARNEIRO, R.G.; MAZAFFERA, P. Relação fonte-dreno e absorção e transporte de minerais em plantas infectadas por nematoides. In: SILVA, J.F.V. Relações parasito-hospedeiro nas meloidoginoses da soja. Londrina: Embrapa Soja, 2001. p.630-693.).

Clone 202 was immune to M. incognita race 1, and none of its growth traits were affected. This is extremely relevant information for coffee production in Espírito Santo, as BARROS et al. (2014)BARROS, A.F.; OLIVEIRA, R.D.L.; LIMA, I.M.; COUTINHO, R.R.; FERREIRA, A.O.; COSTA, A. Root-knot nematodes, a growing problem for Conilon coffee in Espírito Santo state, Brazil. Crop Protection, v.55, p.74-79, 2014. https://doi.org/10.1016/j.cropro.2013.10.004
https://doi.org/10.1016/j.cropro.2013.10... identified M. incognita (race 1 and 2), M. Exigua and M. paranaensis in coffee plants grown from north to the south of Espírito Santo. None of the clone 202 variables was reduced, because the plant was immune. It is also noteworthy that there is little information in literature about genetic resistance and damage caused by the main species of Meloidogyne spp. to clones of clonal varieties grown in Espírito Santo. In some studies, such as the one by SERA et al. (2006)SERA, G.H.; SERA, T.; AZEVEDO, J.A.D.; MATA, J.S.D.; RIBEIRO-FILHO, C.; DOI, D.S.; ITO, D.S.; FONSECA, I.C.; FONSECA, I.C.D.B. Porta-enxertos de café robusta resistentes aos nematóides Meloidogyne paranaensis e M. incognita raças 1 e 2. Semina: Ciências Agrárias, Londrina, v.27, n.2, p.171-184, 2006. https://doi.org/10.5433/1679-0359.2006v27n2p171
https://doi.org/10.5433/1679-0359.2006v2... , Conilon 10-1 and 10-2 were resistant to races 1 and 2 of M. incognita and M. paranaensis.

Some C. canephora clones show resistance and/or tolerance to root-knot nematodes. Their use as rootstocks for the production of seedlings to be used in fields infested by Meloidogyne spp. is reported and indicated as a successful management measure in several Arabica coffee-producing regions in the states of Paraná and São Paulo (LIMA et al., 2010LIMA, I. M.; COSTA, H.; VENTURA, J. A. Aumenta incidência de nematoide no cafeeiro. Revista Campo e Negócio, Uberlândia, maio, p.82-83, 2010.). Thus, this is the importance of clone 202 immunity observed in the present study, i.e. it can be evaluated in future breeding programs as a possible rootstock.

According to WANGAI et al. (2014)WANGAI, K.J.; NZESYA, M.J.; MAINA, M.W.; PETER, W.M.; ELIJAH, G.K. Reaction of selected coffee germplasm to root-knot nematodes in Kenya. Journal of Natural Sciences Research, v.4, n.3, p.68-75, 2014., one of the main mechanisms of coffee resistance to nematodes is hypersensitivity. The authors evaluated the reaction of ten varieties of coffee C. arabica and C. canephora to M. incognita and reported different reactions of the genotypes, from susceptible to resistant, with four genotypes of C. canephora showing resistance to the nematode.

The development of coffee varieties that are resistant to Meloidogyne spp. is the most economical and practical option for the sustainable management of these pathogens (MAREDIA et al., 2003MAREDIA, K.M.; DAKON, D.; MOTA SANCHEZ, D. Integrated pest management in the global arena. Wallingford, UK: CABI Publishing, 2003.; ROSSKOPF et al., 2005ROSSKOPF, E.N.; CHELLENI, N.; KOKALIS, B.; CHURCH, G.T. Alternatives to methyl Bromide: A Florida perspective. Crop Protection Journal, v.8, n.3, p.56-80, 2005. https://doi.org/10.1094/APSnetFeature/2005-0605
https://doi.org/10.1094/APSnetFeature/20... ). Resistant varieties have a 32% reduction in damage to their roots (CAMPOS; VILLAIN, 2005CAMPOS, V.P.; VILLAIN, L. Nematodes parasites of coffee and cocoa. In: LUC, M.; SIKORA, R.A.; BRIDGE, J. (Eds.). Plant parasitic nematodes in subtropical and tropical agriculture. 2. ed. Egham, UK: CABI Bioscience, 2005. p.529-579.; CASTILLO; WINTGENS, 2009CASTILLO, G.; WINTGENS, J.N. Nematodes in coffee. In: WINTGENS, J.N. Coffee: growing, processing, sustainable production. A guidebook for growers, processors, traders and researchers. 2. ed. 2009. p.478-494. https://doi.org/10.1002/9783527619627.ch17
https://doi.org/10.1002/9783527619627.ch... ). Several studies have demonstrated the resistance of C. canephora var. Robusta to Meloidogyne spp. species (WHITEHEAD, 1998WHITEHEAD, A.G. Plant Nematode Control. Oxon, UK; New York, NY, USA: CAB International, 1998.; CAMPOS; VILLAIN, 2005CAMPOS, V.P.; VILLAIN, L. Nematodes parasites of coffee and cocoa. In: LUC, M.; SIKORA, R.A.; BRIDGE, J. (Eds.). Plant parasitic nematodes in subtropical and tropical agriculture. 2. ed. Egham, UK: CABI Bioscience, 2005. p.529-579.; CASTILLO; WINTGENS, 2009CASTILLO, G.; WINTGENS, J.N. Nematodes in coffee. In: WINTGENS, J.N. Coffee: growing, processing, sustainable production. A guidebook for growers, processors, traders and researchers. 2. ed. 2009. p.478-494. https://doi.org/10.1002/9783527619627.ch17
https://doi.org/10.1002/9783527619627.ch... ).

Some resistant C. canephora hybrids to many species of root-knot nematodes and races of M. incognita have also been developed in some countries, such as: Robusta variety T3561X T3751 in El Salvador, Nemaya variety whose ancestors are T3751 and T3561 and Apoatã in Brazil (BERTRAND et al., 2001BERTRAND, H.G.; ANZUETO, F.; SARA, J.L. Resistance of Meloidogyne exigua in Coffee arabica accession in Ethiopia. Euphytica, v.118, n.1, p.1-8, 2001.; CAMPOS; VILLAIN, 2005CAMPOS, V.P.; VILLAIN, L. Nematodes parasites of coffee and cocoa. In: LUC, M.; SIKORA, R.A.; BRIDGE, J. (Eds.). Plant parasitic nematodes in subtropical and tropical agriculture. 2. ed. Egham, UK: CABI Bioscience, 2005. p.529-579.; CASTILLO; WINTGENS, 2009CASTILLO, G.; WINTGENS, J.N. Nematodes in coffee. In: WINTGENS, J.N. Coffee: growing, processing, sustainable production. A guidebook for growers, processors, traders and researchers. 2. ed. 2009. p.478-494. https://doi.org/10.1002/9783527619627.ch17
https://doi.org/10.1002/9783527619627.ch... ; CABOS et al., 2010CABOS, R.Y.N.; SIPES, B.S.; SORAIN, M.; SCHMITT, D.P. Evaluation of coffee genotypes for root knot nematodes resistance. Nematotropica, v.40, 191-202, 2010.). The Romex variety is currently being used in Mexico, whose clones R34, R37 and R48 have shown tolerance to root-knot nematodes (CASTILLO; WINTGENS, 2009CASTILLO, G.; WINTGENS, J.N. Nematodes in coffee. In: WINTGENS, J.N. Coffee: growing, processing, sustainable production. A guidebook for growers, processors, traders and researchers. 2. ed. 2009. p.478-494. https://doi.org/10.1002/9783527619627.ch17
https://doi.org/10.1002/9783527619627.ch... ; WINTGENS, 2009WINTGENS, J.N. Coffee: growing, processing, sustainable production. A Guidebook for growers, processors, traders and researchers. 2nd rev. ed. Weinheim, WILEY-VCH Verlag GmbH & Co. KGaA, 2009. https://doi.org/10.1002/9783527619627
https://doi.org/10.1002/9783527619627... ).

CARNEIRO et al. (2009)CARNEIRO, R.M.D.G.; COSTA, S.B.; SOUZA, F.R.; SANTOS, D.F.; ALMEIDA, M.R.A.; SANTOS, M.F.A.; SIQUEIRA, K.M.S.; TIGANO, M.S.; FONSECA, A.F.A. Reação de cafeeiros ‘conilon’ a diferentes populações de Meloidogyne spp. In: SIMPÓSIO DE PESQUISA DOS CAFÉS DO BRASIL, 6., 2009. Vitória, 2009. evaluated the resistance of C. canephora clones of the “Vitoria – Incaper 8142” variety to different populations of Meloidogyne spp. They concluded that there are sources of genetic resistance in varieties of the Conilon group to populations of M. paranaensis, M. exigua and M. incognita. However, there have been no reports on resistance in the clonal variety “Jequitibá Incaper 8122” yet.

The presence of M. incognita race 1 reduced CHLO in five of the nine clones (201, 204, 206, 207 and 209). Nutrients essential to the constitution of the chlorophyll molecule have their absorption affected by phytonematode parasitism (GONÇALVES et al., 1995GONÇALVES, W.; MAZZAFERA, P.; FERRAZ, L. C.C.B.; SILVAROLLA, M.B.; LIMA, M.M.A. Biochemical basis of coffee tree resistance to Meloidogyne incognita. Plantations, Recherche, Developpement, v.2, n.1, p.54-58, 1995.). CC allows evaluating the intensity index of the green color in several plant species (NASCIMENTO JUNIOR, 2012NASCIMENTO JUNIOR, V.C. Aplicação de 1-Metilciclopropeno em soja sob déficit hídrico e seus reflexos na fixação biológica do nitrogênio. 72f. 2012. Dissertation (Master degree in Agronomy) – Centro de Ciências Agrárias, Universidade Estadual de Londrina, Londrina, 2012.). Pigment loss is a visible indicator of events such as stress or water deficiency in plants. According to ASMUS (2001)ASMUS, G.L. Relações densidade populacional Meloidogyne javanica e Heterodera glycines (Nemata: Tylenchoidea), a área foliar, a fotossíntese e os danos causados a variedades de soja. 2000. Thesis (Doctorate degree in Phytopathology) ‒ Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, 2001. https://doi.org/10.11606/T.11.2019.tde-20191220-142837
https://doi.org/10.11606/T.11.2019.tde-2... , phytonematodes may cause water stress in plants to the point of intervening in the CC, which may explain the results of the present research.

Conilon coffee is a diploid, self-sterile plant, allogamous due to gametophytic self-incompatibility (CONAGIN; MENDES, 1961CONAGIN, C.H.T.M.; MENDES, A.J.T. Pesquisas citológicas e genéticas em três espécies de Coffea: autoincompatibilidade em Coffea canephora. Bragantia, v.20, n. único, p.788-804, 1961. http://dx.doi.org/10.1590/S0006-87051961000100034
http://dx.doi.org/10.1590/S0006-87051961... ; PARTELLI et al., 2006PARTELLI, F.L.; VIEIRA, H.D.; DETMANN, E.; CAMPOSTRINI, E. Estimativa da área foliar do cafeeiro a partir do comprimento da folha. Revista Ceres, v.53, n.306, p.204-210, 2006.; COVRE et al., 2013COVRE, A.M.; PARTELLI, F.L.; MAURI, A.L.; DIAS, M.A. Crescimento e desenvolvimento inicial de genótipos de café Conilon. Revista Agro@mbiente On-line, v.7, n.2, p.193-202, 2013. https://doi.org/10.18227/1982-8470ragro.v7i2.944
https://doi.org/10.18227/1982-8470ragro.... ). Therefore, when composing clonal varieties, genotypes must be grouped in a way that they not only bring together the characteristics of interest but also enable the maintenance of a broad genetic base, with greater variability to prevent the harmful process of genetic erosion in the future. To this end, clones of the same variety, despite having a series of agronomic characteristics in common, must be distinct in their genetic makeup, providing greater security and stability to coffee growers who choose them for planting (FERRÃO et al., 2004FERRÃO, R.G.; FONSECA, A.F.A.; FERRÃO, M.A.G.; DE MUNER, L.H.; VERDIN FILHO, A.C.; VOLPI, P.S.; MARQUES, E.M.G.; ZUCATELI, F. Café conilon: técnicas de produção com variedades melhoradas. Vitória: Incaper, 2004. 60p. (Incaper: Circular Técnica, 03 – I).). Based on this information, differences found between the clones of the “Jequitibá” variety regarding characteristics such as NOL, NPB, NN, CHLO, SDM and RFM may have been verified by the genetic differences between the nine clones that compose this variety, and not only by M. incognita race 1 parasitism.

Conilon coffee is a plant influenced by the conditions imposed on it at the time of planting and during the conduction of the crop. A variety with high genetic and productive potential may have its development compromised by abiotic and biotic stresses, such as M. incognita parasitism. With the increasingly occurrence of nematode parasitism in the main varieties already established in the state of Espírito Santo (BARROS et al., 2014BARROS, A.F.; OLIVEIRA, R.D.L.; LIMA, I.M.; COUTINHO, R.R.; FERREIRA, A.O.; COSTA, A. Root-knot nematodes, a growing problem for Conilon coffee in Espírito Santo state, Brazil. Crop Protection, v.55, p.74-79, 2014. https://doi.org/10.1016/j.cropro.2013.10.004
https://doi.org/10.1016/j.cropro.2013.10... ), there is uncertainty as to the future of these new launched clones. Thus, information such as that generated by this work is of fundamental importance for planning the implantation of Conilon coffee crops of the “Jequitibá Incaper 8122” variety if the planting site has already shown signs of M. incognita race 1.

This scientific paper demonstrated the importance of studying the infectivity and damage caused in Conilon coffee by M. incognita race 1, a destructive nematode disseminated in areas where Conilon coffee is grown in the state of Espírito Santo, as well as in other agricultural areas of the world. With this information, technicians and extension workers will have more subsidies to indicate varieties/clones of Conilon coffee with levels of resistance to this pathogen at the time of implantation or renovation of coffee plantations.

ACKNOWLEDGMENTS:

We thank the Nucleus for Scientific and Technological Development in Phytosanitary Management of Pests and Diseases (NUDEMAFI), from the Universidade Federal de Espírito Santo (UFES), for their support in carrying out research work.

REFERENCES

Publication Dates

History