Tropical Plant Pathology (2009) 34, 313-321

Antonio C.T. da Costa, Leandro B. de Oliveira, Margarida Goréte F. do Carmo and Carlos Pimentel (2009)
Avaliação visual e do potencial fotossintético para quantificação da ferrugem do milheto pérola e correlações com a produção
[Rust quantification by visual and photosynthetic potential evaluation and its correlations with production in families of pearl millet]
Tropical Plant Pathology 34 (5), 313-321
Abstract: The aim of the present study was to quantify rust disease caused by Puccinia substriata var. penicillariae in pearl millet and its correlations with yield components. The rust quantification was done by visual evaluations using two scales based on visual description, in five plants per plot in three different kinds of samples: entire plant and fifth and second leaves. Using these values of the area under the disease progress curve (AUDPC) the residual correlation (r_e) and genetic correlations (r_g) were calculated between the values of AUDPC and production of grain, total dry matter and stover dry weight. The evaluation of rust severity on the second leaf, from the flowering stage of pearl millet, was the most efficient method to quantify the disease because of the higher correlation with biomass and grain production. A second assay was conducted in a greenhouse to quantify rust disease indirectly by measuring photosynthetic potential (Fv/Fm), by chlorophyll "a" fluorescence emission, in leaves of six genotypes: HKP, Guerguera, Souna III, BRS 1501 and ENA 1 and bulk ENA 2. In this assay, it was demonstrated that rust affected the photosynthetic potential of pearl millet leaves and that the measurement of chlorophyll "a" fluorescence, which is rapid and independent of evaluator, would be a physiological parameter for selection of rust-resistant genotypes.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: Portuguese)
Full text of article

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
damage/losses/economics

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Puccinia substriata	Pearl millet (Cenchrus americanus)	Brazil (south)