63ª Reunião Anual da SBPC

E. Ciências Agrárias - 1. Agronomia - 5. Agronomia

Pigments in Phaseolus vulgaris plants subjected to two Colletotrichum lindemuthianum races

Juliana Cristina de Castro Budel 1 Argemiro Pereira Martins Filho 1 Eldenira Barbosa Uchôa 1 Emilly dos Santos Pereira 1 Izabelle Pereira Andrade 1 Allan Klynger da Silva Lobato 1

1. Núcleo de Pesquisa Vegetal Básica e Aplicada, Univesidade Federal Rural da Amazônia

INTRODUÇÃO:

Chlorophylls are pigments localized into chloroplasts, and main functions are reception and storage of light energy. Others pigments such as carotenoids are accessory pigments involved in lipid membrane stabilization in chloroplasts and in photosystem protection. Anthracnose is one of mains diseases in common bean crop, which etiologic agent Colletotrichum lindemuthianum (Sacc and Magn.) can infect plant in all the stages and several regions such as root, stem, leaf, pod and seed. Recent study described by indicates that Colletotrichum lindemuthianum infection in Phaseolus vulgaris plants provokes significant decrease in carotenoids and chlorophyll. Objective of this investigation was to evaluate modifications produced by two Colletotrichum lindemuthianum races (7 and 2047) on pigments in Phaseolus vulgaris plants (Mexico 222).

METODOLOGIA:

The study was conducted in greenhouse and growth chamber conditions located in Núcleo de Pesquisa Aplicada à Agricultura (Nupagri), Universidade Estadual de Maringá (UEM).Seeds of Phaseolus vulgaris Mexico 222 cultivar, which presents a determined growth, it was obtained from the Nupagri seed bank. Pathogen employed to infect the plants was the fungus Colletotrichum lindemuthianum races 7 and 2047, where Mexico 222 is resistant and susceptible to races 7 and 2047, respectively. Plants were grown in greenhouse conditions controlled by the local weather minimum/maximum temperature was 34.8/13.5ºC and relative humidity was 55/81%, respectively, during the experimental period. Inoculum obtained from Nupagri was transferred culture tubes that contained growing medium and immature pod beans. Experimental design employed was completely randomized with 3 treatments (control, resistant and susceptible). The experiment was composed of six replicates, and thirty six experimental units (1 plant in each unit). In this study were evaluated carotenoids and total chlorophyll in 8th after inoculation, being measured in well expanded trifoliolate leaves 3rd, located at the middle of the main branch at the stage V4. Pigments were quantified according to Lichthenthaler (1987). Data were analyzed employing a variance analysis, and using Scott-Knott test at 5% level of probability. Standard errors were also calculated in all treatments evaluated.

RESULTADOS:

Results linked to carotenoids levels present 0.88, 0.71, and 0.69 mg g FM-1 in control, resistant and susceptible treatments, respectively, and these data reveal reduction not significant among treatments. reported similar lower carotenoid levels when plants of Phaseolus vulgaris were infected by Colletotrichum lindemuthianum race 23. In total chlorophyll was showed significant interference promoted by Colletotrichum lindemuthianum races when infected Mexico 222. In addition, decreases produced by 7 and 2047 races were of 19.3 and 21.5%, respectively, with respect to control. Fall significant obtained in resistant treatment can be associated to lower decreases in clorophylls a and b (data not shown). However, reduction revealed in susceptible treatment is promoted by pathogen infection and consequent disorders in leaf pigments.

CONCLUSÃO:

Carotenoids level in common bean plants presented not difference among treatments studded. However, in total chlorophyll was showed significant reduction in susceptible plants.

Palavras-chave: chlorophylls, Phaseolus vulgaris, carotenoids.