scholarly journals Plant adaptation to temperature and photoperiod

1996 ◽  
Vol 5 (3) ◽  
pp. 251-260 ◽  
Author(s):  
Olavi Junttila

Plants respond to environmental conditions both by adaptation and by acclimation. The ability of the plants to grow, reproduce and survive under changing climatic conditions depends on the efficiency of adaptation and acclimation. The adaptation of developmental processes in plants to temperature and photoperiod is briefly reviewed. In annual plants this adaptation is related to growth capacity and to the timing of reproduction. In perennial plants growing under northern conditions, adaptation of the annual growth cycle to the local climatic cycle is of primary importance. Examples of the role of photothermal conditions in regulation of these phenological processes are given and discussed. The genetic and physiological bases for climatic adaptation in plants are briefly examined.

Plant Disease ◽  
2019 ◽  
Vol 103 (11) ◽  
pp. 2877-2883 ◽  
Author(s):  
Amit M. Philosoph ◽  
Aviv Dombrovsky ◽  
Yigal Elad ◽  
Amnon Koren ◽  
Omer Frenkel

Some diseases are caused by coinfection of several pathogens in the same plant. However, studies on the complexity of these coinfection events under different environmental conditions are scarce. Our ongoing research involves late wilting disease of cucumber caused by coinfection of Cucumber green mottle mosaic virus (CGMMV) and Pythium spp. We specifically investigated the role of various temperatures (18, 25, 32°C) on the coinfection by CGMMV and two predominant Pythium species occurring in cucumber greenhouses under Middle Eastern climatic conditions. During the summer months, Pythium aphanidermatum was most common, whereas P. spinosum predominated during the winter–spring period. P. aphanidermatum preferred higher temperatures while P. spinosum preferred low temperatures and caused very low levels of disease at 32°C when the 6-day-old seedlings were infected with P. spinosum alone. Nevertheless, after applying a later coinfection with CGMMV on the 14-day-old plants, a synergistic effect was detected for both Pythium species at optimal and suboptimal temperatures, with P. spinosum causing high mortality incidence even at 32°C. The symptoms caused by CGMMV infection appeared earlier as the temperature increased. However, within each temperature, no significant influence of the combined infection was detected. Our results demonstrate the complexity of coinfection in changing environmental conditions and indicate its involvement in disease development and severity as compared with infection by each of the pathogens alone.


Author(s):  
Yu. Е. Kolupaev ◽  
◽  
Е. I. Gorelova ◽  
Т. О. Yastreb ◽  
◽  
...  

Agronomy ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 46
Author(s):  
Cristina Mihaescu ◽  
Daniel Dunea ◽  
Adrian Gheorghe Bășa ◽  
Loredana Neagu Frasin

Phomopsis juglandina (Sacc.) Höhn., which is the conidial state of Diaporthe juglandina (Fuckel) Nitschke, and the main pathogen causing the dieback of branches and twigs of walnut was recently detected in many orchards from Romania. The symptomatological, morphological, ultrastructural, and cultural characteristics, as well as the pathogenicity of an isolate of this lignicolous fungus, were described and illustrated. The optimum periods for infection, under the conditions prevailing in Southern Romania, mainly occur in the spring (April) and autumn months (late September-beginning of October). Strong inverse correlations (p < 0.001) were found between potential evapotranspiration and lesion lengths on walnut branches in 2019. The pathogen forms two types of phialospores: alpha and beta; the role of beta phialospores is not well known in pathogenesis. In Vitro, the optimal growth temperature of mycelial hyphae was in the range of 22–26 °C, and the optimal pH is 4.4–7. This pathogen should be monitored continuously due to its potential for damaging infestations of intensive plantations.


2021 ◽  
Author(s):  
Irina Yu. Kudrevatykh ◽  
Pavel I. Kalinin ◽  
Gennady V. Mitenko ◽  
Andrey O. Alekseev

1990 ◽  
Vol 10 (2) ◽  
pp. 549-560 ◽  
Author(s):  
S A Nadin-Davis ◽  
A Nasim

We have further investigated the function of the ras1 and byr1 genes, which were previously shown to be critical for sexual differentiation in fission yeast cells. Several physiological similarities between strains containing null alleles of these genes supports the idea that ras1 and byr1 are functionally closely related. Furthermore, we have found that byr1 is allelic to ste1, one of at least 10 genes which when mutated can cause sterility. Since ras1 had previously been found to be allelic to ste5, both ras and byr genes are now clearly shown to be a part of the ste gene family, thus confirming their close functional relationship. The observation that the mating-type loci could overcome the sporulation block of ras1 and byr1 mutant strains prompted investigation of the role of the ras-byr pathway in the induction of the mating-type gene transcripts upon nitrogen starvation. By Northern analysis of RNA preparations from strains carrying wild-type or mutant ras1 alleles and grown to different stages of the growth cycle, we have shown that ras1 plays an important role in inducing the Pi transcript of the mating-type loci and the mei3 gene transcript. These observations provide a molecular basis for the role of the ste gene family, including ras1 and byr1, in meiosis and indicate that further characterization of other ste genes would be very useful for elucidating the mechanism of ras1 function in fission yeast cells.


PEDIATRICS ◽  
1963 ◽  
Vol 31 (6) ◽  
pp. 909-918
Author(s):  
Nathan B. Talbot

WHILE MEDICAL HISTORIANS cannot provide us with accurate statistics concerning the incidence of rickets and scurvy in centuries past, they leave little room for doubt about the high prevalence of these disorders prior to the advent of modern scientific medicine. Thus, Castiglione has written that in the sixteenth century scurvy raged throughout northern Europe, in Scandinavia, on the shores of the Baltic, and in the interior of Germany. It is interesting to note, however, that Jacques Cartier, whose sailors had been ravaged by scurvy, learned in 1536 from the Indians that the malady could be cured by juices of the almeda tree. This was 200 years before James Lind demonstrated the curative effects of lemon juice in his treatise on scurvy published in 1753 and almost 400 years before ascorbic acid, which was isolated by Szent-Gyorgi in 1928, was recognized to be vitamin C by Waugh and King in 1932. Rickets, likewise, was occurring in a large portion of children prior to the discovery of the existence of vitamin D by Hess, Steinbock, and Windaus in 1918, of its therapeutic value by Mellanby in 1919, of the equivalent role of sunlight by Hess in 1921, and of the chemical composition of the vitamins by Windaus in 1922. But 200 years earlier Friedrick Hoffman had the answer to the control of this disease almost in hand. He attached much importance to climatic conditions as a factor in rickets, noting that if anything is specially powerful in producing this affliction, it is a surrounding atmosphere of cold foggy air. He cited as striking evidence of this the famous emporium of England, London, which he found to be specially apt to produce and foster this disease.


2021 ◽  
Vol 18 (1) ◽  
pp. 52-65
Author(s):  
P. N. Mikheev

The article discusses issues related to the impact of climate change on the objects of the oil and gas industry. The main trends in climate change on a global and regional (on the territory of Russian Federation) scale are outlined. Possible approaches to the identification and assessment of climate risks are discussed. The role of climatic risks as physical factors at various stages of development and implementation of oil and gas projects is shown. Based on the example of oil and gas facilities in the Tomsk region, a qualitative assessment of the level of potential risk from a weather and climatic perspective is given. Approaches to creating a risk management and adaptation system to climate change are presented.


2017 ◽  
Vol 35 (0) ◽  
Author(s):  
A. TANVEER ◽  
M.M. JAVAID ◽  
R.N. ABBAS ◽  
H.H. ALI ◽  
M.Q. NAZIR ◽  
...  

ABSTRACT Catchfly (Silene conoidea), an annual herb, is usually recognized as an emerging weed species in Eurasia and North America. The presence of somatic seed polymorphism might aid in the adaptation of this weed in different climatic conditions. We conducted laboratory and greenhouse experiments to study the seed polymorphism and influence of various environmental factors like temperature, salt stress, osmotic stress and burial depth on the germination and emergence characteristics of catchfly. Optimum germination of seeds of all colors was recorded at a temperature of 15 oC. Germination of catchfly seeds of all colors followed decreasing trend as NaCl concentration increased from 50 mM to 200 mM. Seed germination was maximum (87-96%) at 0 MPa but gradually decreased to 40% as osmotic stress increases up to -0.4 MPa and completely inhibited at 0.6 MPa of all seed colors. A slight increase (from 60 to 95%) in the germination of seeds of black and dark brown colors was observed when seeding depth increased from 0 to 2 cm but decreased when seeding depth increased from 2 to 4 cm in seeds of all colors. There was no emergence of catchfly at seeding depth of 6 cm or greater. Our results concluded that catchfly seeds have the potential to germinate and emerge in various environmental conditions, but germination/emergence percentage of seeds of all colors will be different in different environmental conditions. Soil amendments including deep ploughing may aid for the successful management of this weed in cultivated areas.


Sign in / Sign up

Export Citation Format

Share Document