Interpreting variability among isolates of Macrophomina phaseolina in pathogenicity, pycnidium production, and chlorate utilization

1995 ◽  
Vol 73 (10) ◽  
pp. 1596-1603 ◽  
Author(s):  
J. D. Mihail ◽  
S. J. Taylor
Keyword(s):  
General Population ◽  
Reproductive Isolation ◽  
Key Words ◽  
East Africa ◽  
Initial Level ◽  
Macrophomina Phaseolina ◽  
Host Tissue ◽  
Host Specialization ◽  
Geographic Isolation ◽  
Tissue Source

One hundred and fourteen isolates of Macrophomina phaseolina from tissue of hosts in the Asteraceae, Euphorbiaceae, Fabaceae, and Poaceae, and from cultivated and noncultivated soils in Somalia (east Africa) and Arizona were tested for pathogenicity, ability to form pycnidia, and chlorate-utilization phenotype. Hyphal interactions of pairs of isolates from noncultivated soils in Somalia and Arizona were examined to address the possibility of genetic reproductive isolation of two geographically separated populations. Isolates from the Poaceae were less pathogenic and formed pycnidia less frequently compared with isolates from dicot host tissue. Chlorate-utilization phenotype was unrelated to host tissue source. However, isolates that infrequently or never produced pycnidia were more likely to have chlorate-sensitive phenotypes. Apparently successful hyphal fusions were observed for 64.3% of confrontations where one isolate was taken from Arizona and one was from Somalia, implying no barrier to genetic interchange at this initial level of interaction. While M. phaseolina is a heterogeneous species that cannot be partitioned into distinct subspecific groups based upon function, it appears that isolates colonizing the Poaceae are more restricted in pathogenicity than the general population. Key words: chlorate utilization, geographic isolation, host specialization, hyphal interactions, Macrophomina phaseolina.

scholarly journals Geographic isolation facilitates the evolution of reproductive isolation and morphological divergence

2017 ◽  
Vol 7 (23) ◽  
pp. 10278-10288 ◽  
Author(s):  
McLean L. D. Worsham ◽  
Eric P. Julius ◽  
Chris C. Nice ◽  
Peter H. Diaz ◽  
David G. Huffman
Keyword(s):  
Reproductive Isolation ◽  
Morphological Divergence ◽  
Geographic Isolation

Inoculation of Euphorbia lathyris with cotton strings infested with Macrophomina phaseolina, causal agent of charcoal rot disease

1991 ◽  
Vol 69 (3) ◽  
pp. 682-685
Author(s):  
Phyllis T. Himmel
Keyword(s):  
Key Words ◽  
Macrophomina Phaseolina ◽  
Causal Agent ◽  
Silica Sand ◽  
Optimal Conditions ◽  
Lesion Development ◽  
Charcoal Rot ◽  
Temperature Regimes ◽  
Rot Disease ◽  
Euphorbia Lathyris

Root infections caused by Macrophomina phaseolina were initiated under optimal conditions for the host, Euphorbia lathyris. Two-week-old Euphorbia lathyris seedlings were inoculated by tying roots with cotton strings infested with Macrophomina phaseolina. Ninety-three per cent of the inoculated roots developed infections after 2 weeks incubation in silica sand at 25 °C. By using infested strings, differences in the incidence of lesion development were detected when infected roots were subjected to differing temperature regimes. After approximately 6 weeks, there was a significantly [Formula: see text] greater incidence of lesion development at 34 °C than at 25 °C, whereas there was no difference in the incidence of infection. Aerial symptoms indicative of charcoal rot were not observed during the course of these studies. Key words: infested strings, charcoal rot.

The remote results of treatment spironolactonum of teenage girls with hypomenstrual syndrome

2018 ◽  
pp. 26-29
Author(s):  
S.O. Levenets ◽  
◽  
N.O. Udovikova ◽  
S.V. Novokhatskaya ◽  
D.A. Kashkalda ◽  
...  
Keyword(s):  
Body Weight ◽  
Menstrual Cycle ◽  
Key Words ◽  
Initial Level ◽  
Informational Content ◽  
Teenage Girls ◽  
Negative Results ◽  
Results Of Treatment ◽  
Immunoenzymatic Method

The objective: to allocate the clinico-anamnestic and hormonal and metabolic indicators influencing the remote results of treatment Spironolactonum. Materials and methods. 78 girls at the age of 13–17.5 years with a hypomenstrual syndrome are surveyed (НMS: an oligomenorrhea – OHM, a secondary amenorrhea – VA) in 2 years and more after an initiation of treatment Spironolactonum (3 ten-day courses). The menstrual age (MA), the perinatal anamnesis, НMS duration prior to treatment, the index of body weight (IBW), uterus volume according to ultrasonic examination (US) of organs of a small pelvis, degree of expression of a hirsutism, contents in a cow of gonadotrophic, sex hormones, рrolactinum (PRL), insulin were studied by an immunoenzymatic method. The prognostic coefficient (PC) and its informational content were defined (I). The criterion of efficiency of treatment is an independent regular menstrual cycle. Results. The remote efficiency of treatment at OHM reached 62.9%, at VA – only 20.1% (Р < 0.001). The most prognostically significant relatively positive takes of treatment is the MV up to 2 years (PC = +5.13; I = 0.542), rather negative results – VA (PC = - 3.54; I = 0.545), a hirsutism of the II–III Art. on Ferrimana-Gаlvey’s scale, the increased LG level (PC = - 3.52; I = 0.59) and the lowered contents in blood estradiolum (PC = - 3.68; I = 0.36). Conclusions. The separated efficiency of treatment Spironolactonum within three months is 3 times better at OHM, than at VA. Girls with НMS demand inspection and treatment in the first 1–1.5 years after a menarche. Special attention should be paid to girls with the expressed hirsutism, to at what disorders of menstrual function remain within 2 years and more, with the LG high initial level and the lowered content in blood estradiolum. Key words: teenage girls, hypomanstrual syndrome, spironolactone, long-term effectiveness, гирсутизм, estradiol.

The native rust fungi of Hawaii

1994 ◽  
Vol 72 (7) ◽  
pp. 976-989 ◽  
Author(s):  
Donald E. Gardner
Keyword(s):  
Key Words ◽  
Hawaiian Islands ◽  
Rust Fungi ◽  
Geographic Isolation ◽  
Comprehensive List

F.L. Stevens (1925. Bernice P. Bishop Mus. Bull. No. 19) published the first comprehensive list of fungi in Hawaii, recognizing 7 species of endemic rusts and 10 species probably indigenous. Stevens considered this small number of rusts particularly noteworthy in comparison with the rust floras of other areas with which he was familiar. He ascribed the scarcity to the geographic isolation of the Hawaiian Islands from significant land masses. Currently, of the more than 74 rusts in Hawaii, 22 are considered native, of which 13 are endemic and 9 indigenous. The rust flora, like other groups of native organisms of Hawaii, provides interesting examples of biological colonization and adaptation to remote insular environments. Key words: endemic, Hawaii, indigenous, rusts.

Contribution of Life History Information to Taxonomy of Aquatic Insects

1979 ◽  
Vol 36 (3) ◽  
pp. 318-321 ◽  
Author(s):  
D. R. Oliver
Keyword(s):  
Life History ◽  
Reproductive Isolation ◽  
Key Words ◽  
Aquatic Insects ◽  
Life Histories ◽  
Life Stages ◽  
History Information ◽  
Character Evaluation

Life history studies may contribute to taxonomy by providing corroborative or clarifying data about existing taxonomic systems or may suggest reevaluation. Specifically, life history studies may provide information on the presence or absence of reproductive isolation, associated life stages, monospecific specimens, specimens for character evaluation, and a forum where ecologists and taxonomists may interact. Key words: taxonomy, life histories, benthos, reproductive isolation, life stages, character evaluation

THE RUSTS OF ERIOGONUM, CHORIZANTHE, AND OXYTHECA

1966 ◽  
Vol 44 (9) ◽  
pp. 1151-1170 ◽  
Author(s):  
D. B. O. Savile
Keyword(s):  
British Columbia ◽  
North America ◽  
Host Plants ◽  
Host Specialization ◽  
Western North America ◽  
Geographic Isolation ◽  
The Past ◽  
Species Groups

Uromyces intricatus is broken into six varieties. Var. umbellati and var. major attack montane and lowland species of Eriogonum subgen. Eueriogonum in much of western North America, and the former probably attacks Oxytheca. Vars. intricatus (Oregon, California), parvifolii (California), nivei (interior British Columbia to Arizona), and pluriporosus (mainly Montana, Wyoming, and Colorado) attack various species or species groups in Eriogonum subgen. Oregonium, the variation being partly geographic and partly due to host specialization. Var. intricatus attacks Chorizanthe spp. and Eriogonum subgen. Ganysma in California. This variety has met and intergraded with var. pluriporosus in the past but the link is now broken. Uromyces bisbyi, a microcyclic derivative of var. parvifolii, is described on Eriogonum parvifolium in California. The implications on the evolution of Eriogonum and the problem of realistic nomenclature of rusts derived from both host and geographic isolation are discussed. A table clarifies the nomenclature of reported host plants.

scholarly journals How to face the association between tobacco and psychosis?

10.3823/2427 ◽  
2017 ◽  
Vol 10 ◽  
Author(s):  
Raphael Tavares Dantas ◽  
Wanderley Gonçalves Cordeiro Júnior ◽  
Marcial Moreno Moreira ◽  
Lídia Coelho do Nascimento Santos ◽  
Sidney Medeiros De Oliveira ◽  
...  
Keyword(s):  
General Population ◽  
Key Words ◽  
Psychotic Disorder ◽  
Age Of Onset ◽  
Age At Onset ◽  
Mean Difference ◽  
First Episode ◽  
Psychotic Illness ◽  
Increased Risk ◽  
Key Words Tobacco

Evidences suggest an association between tobacco and psychosis. However, the reasons why people with psychosis have a higher tendency to smoke than the general population are not yet clear. Recently, Gurillo et al. reported that daily use of tobacco is associated with an increased risk of psychotic disorder and an earlier age of onset of psychotic illness. His study also calculated a significant mean difference in age at onset, expressed in years, and estimated the prevalence of smoking in people with their first episode of psychosis. According to this and other findings, it could be said that the causes of the smoking-schizophrenia association are complex and cannot be explained solely as a result of some aspect of schizophrenia. Thus, new studies in this area are needed, as well as strategies that look for the monitoring of smoking effects in order to reduce it among individuals with schizophrenia. Key-words: Tobacco, Psychosis, Illness.

Resistance to Phytophthora cinnamomi in callus tissue derived from three avocado cultivars

1991 ◽  
Vol 69 (9) ◽  
pp. 2026-2032 ◽  
Author(s):  
D. Phillips ◽  
G. Weste ◽  
J. M. Hinch
Keyword(s):  
Key Words ◽  
Mycelial Growth ◽  
Callus Tissue ◽  
Phytophthora Cinnamomi ◽  
Host Tissue ◽  
Plant Parts ◽  
Whole Plant ◽  
Moderately Resistant ◽  
Undifferentiated Callus

Calli induced from various plant parts of avocado cultivars Topa Topa (susceptible), Duke 7 (moderately resistant), and Martin Grande (resistant) were inoculated with the root and collar rotting pathogen Phytophthora cinnamomi and examined for expression of resistance. Resistance was assessed quantitatively by measuring the rate of hyphal extension across the callus surface from the point of inoculation. Resistance in the callus tissue was associated with sparse, limited mycelial growth, in contrast to prolific, dense growth on and within susceptible callus. Rates of hyphal extension on calli of the resistant ‘Duke 7’ and ‘Martin Grande’ ranged from 1–3 mm day−1 compared with 4–7 mm day−1 on calli of ‘Topa Topa’. This difference in growth was significant (P = 0.05). This is the first report of avocado callus exhibiting resistance to P. cinnamomi and it mirrors that recorded for the whole plant for the three avocado cultivars tested. Thus, the level of resistance expressed by each cultivar appears to be innate whether the host tissue remains in an organized state or is in the form of an undifferentiated callus mass. The basis of the resistance expressed appeared to be largely physiological and (or) biochemical rather than anatomical. Assessing rates of hyphal colonization on undifferentiated callus masses in vitro may provide a new and useful assay for screening and selecting host lines in avocado resistant to P. cinnamomi. Key words: callus, avocado, in vitro, resistance, Phytophthora cinnamomi, Persea.

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