MARIYA YAKOVLEVNA ZEROVA

(1902 – 1994)

Mariya Yakovlevna Zerova

Mariya Yakovlevna Zerova was born in Kazatin (Vinnitsia oblast, Ukraine) in the family of a railway-man. In 1904, her family moved to Kiev. In 1917, after finishing at the women's Mariinskaya secondary school with a silver medal, she entered Kiev Medical Institute. But, after the third year, she had to interrupt her study because of tuberculosis. After recovery, following doctor's advice, she moved to the Biology Faculty of Kiev University (at that time the Institute of Popular Schooling). In 1924, she graduated from the university and for a long time worked as a secondary school teacher. Later, she dedicated herself to science, thereafter studying fungi of different taxonomic and ecological groups. She worked at the Trust of Green Plantations, the Scientific-Research Institute of the Sugar Industry, the Ukrainian Institute of Rubber and Rubber-bearing Plants, and from 1934 till the end of life at the M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine. Studying in the 1930s fungi and diseases of rubber-bearing plants (Asclepias cornuti Decsn., Scorzonera tau-saghys Lipsch. & Bosse etc.), she widely used pure culture techniques and, as a result, discovered and described 4 fungal species new for science (Phyllosticta tau-saghyziana Zerova, Macrosporium tau-saghyzianum Zerova, Myrothecium transchelianum Zerova & Tropova and Melanospora asclepiadis Zerova). In the case of the last species, she demonstrated experimentally that it parasitizes Fusarium solani App. & Wr.

After moving to the Mycological Department of the M.G. Kholodny Institute of Botany, M.Y. Zerova actively studied fungi developing on woody and shrubby plants and ornamental herbaceous plants, which were used for planting of greenery in towns. She conducted a mycological survey of 160 plant species on which she found more than 400 fungi; among them several were described for the first time, including Phomopsis piceae Zerova on Picea abies (L.) Karst., Phomopsis eucalypti Zerova on Eucalyptus sp., Phoma lavitskii Zerova on Ligustrum vulgare L., Coniothyrium cheiranthi Zerova on Cheiranthus cheiri L.

At the same time, M.Y. Zerova initiated research on pleomorphism to establish genetic connexions between ascomycetes and conidial fungi which are merely different stages of development of the same organism. In doing this, she followed procedures laid down by that outstanding Ukrainian mycologist A.A. Potebnia. Using the technique of pure culture, Zerova established the genetic connexion of the conidial fungus Fusarium coeruleum (Lib.) Sacc. with a previously undescribed teleomorph Hypomyces asclepiadis Zerova. By looking at anatomy and morphology of fungi developing on withering and dying shrub branches, using ultra-thin sections, she demonstrated transitions from anamorph to teleomorph. Thus on branches of Ribes nigrum L. she showed that the conidial fungus Tubercularia confluens Pers. is the anamorph of the ascomycete Pleonectria ribis Karst., and similarly that the conidial fungus Paradiplodia ribis Zerova is the anamorph of the ascomycete Plowrightia ribesia (Pers.) Sacc. The results of her study of ontogenic relations between ascomycetes and conidial fungi served as a basis for her candidate degree thesis Pleomorphism in some Ascomycetes, which she defended in 1942. In the 1960s, as a recognized specialist on ascomycetes, she published several review articles devoted to the problems of classification and evolution of this group of fungi. She was one of the principal authors of the second volume of Guide to the Identification of Fungi of Ukraine (1969). In this volume numerous families of ascomycetes of Ukraine treated by M.Y. Zerova are presented, including the Chaetomiaceae, Gnomoniaceae, Mycosphaerellaceae, Sordariaceae, Sphaeriaceae and Valsaceae. Furthermore, for this volume, Zerova critically re-assessed genera such as Cucurbitaria S.F. Gray, Diaporthe Nitschke, Leptosphaeria Ces. & de Not., Mycosphaerella Johans., Pleospora Rabenh. and Valsa Nitschke. In the third volume of Guide to the Identification of Fungi of Ukraine (1971), which was devoted to conidial fungi, she critically reviewed compound and bulk genera such as Ascochyta Lib., Camarosporium Schulz., Cytospora Ehrenb. & Fr., Diplodia Fr., Hendersonia Berk., Phoma Fr., Phomopsis Sacc., Phyllosticta Pers. & Desm. and Septoria Fr. Those two volumes from this key work of five-volumes divided into seven books summed up the research on ascomycetes to which Zerova gave up more than a quarter of a century.

From the early 1950s, in connexion with widespread cultivation of steppe in the former Soviet Union, Zerova began to study ectotrophic mycorhizas of trees of Ukraine's steppe zone. In this way, her attention was attracted by the larger basidiomycetes, the main fungal symbionts in mycorhizas. She studied mycorhizas of 87 species of trees and shrubs from 24 families. The research was extended in different directions. Root analysis revealed wood mycotrophs; the species composition of soil fungi was determined and among them mycorhizal symbionts were detected; wood mycotrophs were cultivated in different conditions and on soils of different types (contaminated and free of mycorhizal fungi etc.), and Zerova demonstrated the phenomenon of "spontanous" development of mycorhizas on steppe tree roots. As a result, silviculturists were able to avoid the expensive process of adding mycorhizas to soils (by importing soil from forest zones) in steppe areas destined for tree plantations.

Analysis of the state of knowledge about larger basidiomycetes as generators of mycorhizas showed that both this ecological group and numerous basidiomycetes from another ecological groups were practically unexplored in Ukraine. From studying ectotrophic mycorhizas directly connected with larger basidiomycetes, M.Y. Zerova turned to study their species diversity in Ukraine, beginning with the steppe zone. Numerous expeditions to this area enabled collections of Gasteromycetes, Aphyllophorales and Agaricales to be built up. More than 12,000 specimens of about 1,000 species of larger basidiomycetes from these groups, collected by Zerova in Ukraine's steppe zone, now reside in the Reference Collection of the M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine. Zerova went on to survey the larger Basidiomycetes of many other regions of Ukraine (including the forest zone, the forest-steppe zone and Crimea). As in the case of ascomycetes, she described some species new for science. Very many basidiomycetes collected by Zerova turned out to be new for the former Soviet Union and Ukraine, and the immense material on these fungi which she accumulated served as a basis for the second book of the fifth volume of Guide to the Identification of Fungi of Ukraine (1979). This book dealt with the Gasteromycetes, and the orders Agaricales, Boletales, Entolomatales, Russulales, Tricholomatales and Strobilomycetales (the Tricholomatales and Strobilomycetales being described as new orders Zerova). The volume also contained a number of new genera of larger basidiomycetes, and dozens of new taxonomic and nomenclatural combinations proposed by her. This volume became a milestone in the mycological history of the former Soviet Union, being in fact an encyclopaedia of scientific knowledge on agarics in a wide sense. Along with the splendid Atlas of Ukrainian Fungi, this volume became a manual for many young agaricologists. Zerova also paid a great deal of attantion to popularization of information about edible and poisonous larger basidiomycetes. Her first popular scientific book about edible and poisonous fungi of Ukraine was published in 1963. Later this book was republished several times and was always in demand due to its excellent original pictures and high quality scientific content, set out in an easily assimilable popular format.

The contribution of M.Y. Zerova to mycology was not confined to the achievements described so far. As an expert in pure culture techniques, she used them widely in her research on larger basidiomycetes in the 1970s. Later on, with biochemist colleagues, she initiated a search for biologically active substances in fungal mycelium and in ascocarps. In addition to classical methods, she embraced innovative techniques and enthusiastically introduced them into her mycological research. These included study of microstructures of larger basidiomycetes using the scanning electron microscope, and use of paramagnetic resonance in fungal taxonomy.

M.Y. Zerova was the author of more than 200 scientific works, devoted to pleomorphism in ascomycetes, mycorhizas, relationships of fungi forming ectotrophic mycorhizas with vascular plants, species diversity, systematics, and ontogenetic characteristics of ascomycetes and basidiomycetes. Her long and fruitful scientific activity was appreciated. In 1983, along with other authors of the Guide to the Identification of Fungi of Ukraine, M.Y. Zerova was awarded the National Prize of the Ukraine for Science & Technology. She was also awarded the Order of the Labour Red Banner, and medals and diplomas.

Lists. Publications. Taxa. Kirk & Ansell form of name: Zerova.


Previous page