Review: Women in plant disease management

Women first began to take a stance in science over 50 years ago, and since then, they have produced a great number of publications. However, the first step towards science was a matter of accrediting women as rightful members of the scientific community. During the late nineteenth and early twentieth centuries, women started to enter into graduate programmes, and such a step helped them to make a difference. In many cases and many countries, botanists and mycologists were, in some way, pioneering in the plant pathology discipline. This manuscript considers some of the women who led the way in plant pathology, with a special focus on those who also dealt with the early aspects of plant disease management. Women who were active in different geographical areas are featured, and an attempt has also been made to provide some less well-known stories. Moreover, the importance of women behind the scenes, as is the case for many lab and field technicians, whose lives have not been chronicled, is acknowledged. Finally, some suggestions are given on how to improve the present situation and increase the number of women in science as well as in technical positions, with special emphasis on the positive effect of female mentors and role models

Electrophoretic karyotype variation among pathotypes of Fusarium oxysporum f.sp. dianthi

Karyotype analysis by pulsed-field gel electrophoresis was applied to characterize isolates of Fusarium oxysporum f.sp. dianthi, the causal agent of Fusarium wilt on carnation. Eleven distinct chromosomal DNA patterns were detected among 38 pathogenic isolates, and the total genome size was estimated to range from 23·7 to 36·4 Mb. Except for isolates belonging to pathotypes 2 and 4, all members of the same pathotype shared overlapping electrophoretic karyotypes. Karyotypes of isolates assigned to pathotypes 1 and 8 showed a high degree of similarity, in accordance with VCG and RFLP analysis. The same electrophoretic karyotype was also shared by members of pathotypes 2 and 5, thus confirming results obtained by both VCG and RFLP grouping, A single representative of pathotype 6, previously confined to the same VCG and RFLP group as pathotypes 2 and 5, had a slightly different chromosomal pattern. Isolates assigned to pathotype 4 showed four related karyotypes which partially differed in both the number and size of chromosomal bands. However, all strains assigned to this pathotype shared a basic profile of nine chromosomal bands, while two low-molecular-weight bands were present or absent. The findings are discussed with regard both to the suitability of race distinction in the case of the special form dianthi of F. oxysporum and to the use of karyotype analysis by PFGE as a tool for the study of the population genetics of this fungu

Combined effect of CO2and temperature on wheat powdery mildew development

The effect of simulated climate changes by applying different temperatures and CO₂ levels was investigated in the Blumeria graminis f. sp. tritici/wheat pathosystem. Healthy and inoculated plants were exposed in single phytotrons to six CO₂+temperature combinations: (1) 450 ppm CO₂/18–22°C (ambient CO₂ and low temperature), (2) 850 ppm CO₂/18–22°C (elevated CO₂ and low temperature), (3) 450 ppm CO₂/22–26°C (ambient CO₂ and medium temperature), (4) 850 ppm CO₂/22–26°C (elevated CO₂ and medium temperature), (5) 450 ppm CO₂/26–30°C (ambient CO₂ and high temperature), and (6) 850 ppm CO₂/26–30°C (elevated CO₂ and high temperature). Powdery mildew disease index, fungal DNA quantity, plant death incidence, plant expression of pathogenesis-related (PR) genes, plant growth parameters, carbohydrate and chlorophyll content were evaluated. Both CO₂ and temperature, and their interaction significantly influenced powdery mildew development. The most advantageous conditions for the progress of powdery mildew on wheat were low temperature and ambient CO₂. High temperatures inhibited pathogen growth independent of CO₂ conditions, and no typical powdery mildew symptoms were observed. Elevated CO₂ did not stimulate powdery mildew development, but was detrimental for plant vitality. Similar abundance of three PR transcripts was found, and the level of their expression was different between six phytotron conditions. Real time PCR quantification of Bgt was in line with the disease index results, but this technique succeeded to detect the pathogen also in asymptomatic plants. Overall, future global warming scenarios may limit the development of powdery mildew on wheat in Mediterranean area, unless the pathogen will adapt to higher temperatures

La capacità repressiva di compost nei confronti della tracheofusariosi del basilico

Alcuni compost, addizionati al suolo o impiegati come componenti di substrati per colture in vaso, possono svolgere un’attività repressiva nei confronti dei patogeni terricoli. Nel biennio 2005-2006 sono stati saggiati, a Grugliasco (TO), in serre in ferro/vetro, compost provenienti da aziende di compostaggio presenti sul territorio piemontese al fine di valutarne la loro capacità repressiva. Dai risultati è emerso l’efficace contenimento nei confronti di F. oxysporum f.sp. basilici, da parte di compost prodotto a partire da rifiuti solidi urbani e fanghi, con una diminuzione fino al 50% di piante morte e un incremento fino al 25% di biomassa prodotta a fine ciclo rispetto a quanto rilevato impiegando un ammendante torboso scelto come riferimento