Bean Cultivars Print E-mail
Friday, 13 November 2009 10:56


Bean

Phaseolus vulgaris L.


Symptoms induced in controlled conditions (fumigation with ozone)

cv. Garrafal Oro

Ozone exposure on leaves of bean cv. Garrafal Oro, produces bronze-coloured lesions very close to the main vein (B). Lesions were observed in the old leaves of the plants and young leaves were healthy. Photo A shows the healthy aspect of control (charcoal filtered air) plant.

 

cv. Perona

This bean cultivar was more tolerant to ozone exposure than others as cv. Donna, cv. Bina or cv. Matilda (see photos below). Ozone symptoms were only observed in the tip of the old leaves as a small dark-pigmented lesions (A) and also in some interveinal areas of the leaves (B)

 

cv. Bina

Ozone lesions on upper surface of leaves from bean cv. Bina were observed as a dark-pigmented areas in the old leaves (A), more evident when was compared with healthy control plants (photo A on the left). Lesions gradually join together to cover large parts of the leaves (B) or the complete adaxial leaf surface (C)

 

cv. Donna

Initial appearance of ozone lesions provoked on leaves of bean cv. Donna (A, B and C). This kind of damage produced by ozone exposure can easily confused with spider mite attack (see below in mistaken ozone symptoms). Typically dark-pigmented lesions were observed in bean cv. Donna leaves spread in upper surface of old leaves (D, E, H, I and K), gradually the lesions join together covering small areas (F) or whole leaf surface (G and J). Main veins can be observed green and healthy (A).

 

 

 

cv. Matilda

Different stage of ozone symptoms on leaves of bean cv. Matilda. In the beginning, or in mature leaves, lesions were decoloured areas (A and C); on the other hand, when ozone exposure persists, or in the oldest leaves of the plants, lesions are dark-coloured (B and D).

 

Symptoms observed in the field

Clon S156

In the summer of 2008 and 2009, two genotypes of bean: ozone-sensitive (S156) and ozone-resistant (R123) were tested in Valencia province. Ozone symptoms were observed in sensitive genotype and in resistant one also. Lesions were typical dark-coloured stippling in upper surface of the old leaves (A, B and C). At the end of the trial ambient ozone substantially reduced the biomass of ozone-sensitive genotype (on the left of photo D) compared to ozone-resistant genotype. (More information of this trial with ozone bioindicators can be found in ICP-vegetation webpage and in Snap Bean Project)

 

 

Symptoms observed that can be mistaken for those induced by ozone

Different pest can affect bean leaves producing quite similar ozone-like symptoms. On the margin of the leaves can be observed small-decoloured lesions (A) caused by feeding injuries by adult of leaf miner (Lyriomiza sp). Spider mite (Tetranychus urticae, Koch) on the abaxial part of the leaves (B). Spider mite can produced necrotic areas (1 cm aprox. Photo A) and bronzing (C) or decoloured stippling on the upper part of the affected leaves (D).

 

 

© 2009 Fundación CEAM © 2009 Copyright of the photos: their authors

Last Updated on Friday, 26 February 2010 13:56