Sunspots are Correlated with Foliar pH in Grapevines

Foliar pH is a specific multifaceted parameter that is sensitive to a deficit in soil water and to temperature variations. It also represents a tool that can be used to rapidly phenotype the symbiosis induced in several crops by bio-fertilizers containing Arbuscular Mycorrhizal Fungi. Yearly decreases in foliar pH, which dropped from 3.73 in 2015 to 3.15 in 2017 and then stabilized at around 3.13, have been observed in an experimental vineyard near Torino (Italy) in six grapevine cultivars. In this paper, these curious, original results have been paired with the average sunspots of the 24th sun cycle, proximal to its endpoint. The paired values were highly correlated (r 0.95 P< 0.01), with close parabolic patterns. A lowering in foliar pH has been correlated with a modification of the leaf composition, as characterized by the higher hydration and reinforced wall. An increase in the circulating acidity of the plants has been hypothesized to interfere in a diminution in the general predisposition to block parasite attacks. From this perspective, the retrieval of several historic outbreaks and the long-term systematic monitoring of mud and Erwinia amylovora frequencies have suggested that the hypothesis that links the solar minima with dysfunctions of the plant-pest relationships cannot always be rejected. Cosmic influences pertaining to UV variations are poorly understood in plant physiopathology. Foliar pH appears to be a rapid and simple tool to unveil high-level mechanisms. It is this simple parameter that physiologists and geneticists, but also agronomists, are asked to consider.

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Grazing intensity rather than host plant’s palatability shape the community of arbuscular mycorrhizal fungi in a steppe grassland

10.21203/rs.3.rs-853989/v1 ◽

2021 ◽

Author(s):

Maede Faghihinia ◽

Yi Zou ◽

Yongfei Bai ◽

Martin Dudáš ◽

Rob Marrs ◽

...

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Community Composition ◽

Mycorrhizal Fungi ◽

Rhizosphere Soil ◽

Grazing Intensity ◽

Arbuscular Mycorrhizal ◽

Grass Species ◽

Α Diversity ◽

Steppe Grassland

Abstract Arbuscular mycorrhizal fungi (AMF) are the predominant type of mycorrhizal fungi in roots and rhizosphere soil of grass species worldwide. Grasslands are currently experiencing increasing grazing pressure, but it is not yet clear how grazing intensity and host plant grazing preference by large herbivores interact with soil- and root-associated AMF communities. Here, we tested whether the diversity and community composition of AMF in the roots and rhizosphere soil of two dominant perennial grasses grazed differently by livestock change in response to grazing intensity. We conducted a study in a long-term field experiment in which seven levels of field-manipulated grazing intensities were maintained for 13 years in a typical steppe grassland in northern China. We extracted DNA from the roots and rhizosphere soil of two dominant grasses, Leymus chinense (Trin.) Tzvel. and Stipa grandis P. Smirn, with contrasting grazing preference by sheep. AMF DNA from root and soil samples were then subjected to molecular analysis. Our results showed that AMF α-diversity (richness) at the virtual taxa (VT) level varied as a function of grazing intensity. Different VTs showed completely different responses along the gradient, one increasing, one decreasing and others showing no response. Glomeraceae was the most abundant AMF family along the grazing gradient, which fits well with the theory of disturbance tolerance of this group. In addition, sheep grazing preference for host plants did not explain a considerable variation in AMF α-diversity. However, the two grass species exhibited different community composition in their roots and rhizosphere soils. Roots exhibited a lower α-diversity and higher β-diversity within the AMF community than soils. Overall, our results suggest that long-term grazing intensity might have changed the abundance of functionally-diverse AMF taxa in favor of those with disturbance-tolerant traits. We suggest our results would be useful in informing the choice of mycorrhizal fungi indicator variables when assessing the impacts of grassland management choices on grassland ecosystem functioning.

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Effect of long-term tillage and mineral phosphorus fertilization on arbuscular mycorrhizal fungi in a humid continental zone of Eastern Canada

Plant and Soil ◽

10.1007/s11104-013-1585-4 ◽

2013 ◽

Vol 369 (1-2) ◽

pp. 599-613 ◽

Cited By ~ 34

Author(s):

Min Sheng ◽

Roger Lalande ◽

Chantal Hamel ◽

Noura Ziadi

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Phosphorus Fertilization ◽

Eastern Canada ◽

Mineral Phosphorus

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Long-term effects of alternative and conventional fertilization I: Effects on arbuscular mycorrhizal fungi community composition

Russian Agricultural Sciences ◽

10.3103/s1068367415060245 ◽

2015 ◽

Vol 41 (6) ◽

pp. 454-461 ◽

Cited By ~ 2

Author(s):

Tancredo Augusto Feitosa de Souza ◽

Andrea Fernandes Rodrígues ◽

Luciano Façanha Marques

Keyword(s):

Arbuscular Mycorrhizal Fungi ◽

Community Composition ◽

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Long Term Effects

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Custody of the Myelodysplastic Child: Implications for Selection for Early Treatment

PEDIATRICS ◽

10.1542/peds.53.2.253 ◽

1974 ◽

Vol 53 (2) ◽

pp. 253-256

Author(s):

Patricia W. Hayden ◽

David B. Shurtleff ◽

Arline B. Broy

Keyword(s):

University Hospital ◽

Contributory Factor ◽

Foster Home ◽

Term Care ◽

Long Term Follow Up ◽

Selection For ◽

Foster Home Care ◽

Highly Correlated ◽

High Level

Of 173 patients with myelodysplasia followed in the Birth Defects Center at University Hospital between 1968 and 1972, 30 (17%) have been placed outside their natural families for temporary or long-term care. Only one has been adopted and five have been institutionalized; the remainder have been in foster home care. High level paralysis, mental retardation, and lower socioeconomic status correlate positively with placement. In this series, gender was not a contributory factor. An initial "hopeless" prognosis and/or selection for "no treatment" were decisions often made prior to referral to this center but were highly correlated to placement. Considering the multiple medical, emotional, and economic problems facing these families, relinquishment of custody should be anticipated in a significant percentage of cases. To date, placement outside the natural family has been viewed primarily as abandonment or as an emergency solution to a crisis. Long-term follow-up study of this group of children may indicate that transfer of custody can be a positive therapeutic alternative for the child and his family.

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