Multi-dimensional leaf phenotypes reflect root system genotype in grafted grapevine over the growing season

Background Modern biological approaches generate volumes of multi-dimensional data, offering unprecedented opportunities to address biological questions previously beyond reach owing to small or subtle effects. A fundamental question in plant biology is the extent to which below-ground activity in the root system influences above-ground phenotypes expressed in the shoot system. Grafting, an ancient horticultural practice that fuses the root system of one individual (the rootstock) with the shoot system of a second, genetically distinct individual (the scion), is a powerful experimental system to understand below-ground effects on above-ground phenotypes. Previous studies on grafted grapevines have detected rootstock influence on scion phenotypes including physiology and berry chemistry. However, the extent of the rootstock's influence on leaves, the photosynthetic engines of the vine, and how those effects change over the course of a growing season, are still largely unknown. Results Here, we investigate associations between rootstock genotype and shoot system phenotypes using 5 multi-dimensional leaf phenotyping modalities measured in a common grafted scion: ionomics, metabolomics, transcriptomics, morphometrics, and physiology. Rootstock influence is ubiquitous but subtle across modalities, with the strongest signature of rootstock observed in the leaf ionome. Moreover, we find that the extent of rootstock influence on scion phenotypes and patterns of phenomic covariation are highly dynamic across the season. Conclusions These findings substantially expand previously identified patterns to demonstrate that rootstock influence on scion phenotypes is complex and dynamic and underscore that broad understanding necessitates volumes of multi-dimensional data previously unmet.

Uptake Prediction of Eight Potentially Toxic Elements by Pistia stratiotes L. Grown in the Al-Sero Drain (South Nile Delta, Egypt): A Biomonitoring Approach

The potential to utilise the free-floating macrophyte Pistia stratiotes L. to survey contamination of the Al-Sero Drain in the South Nile Delta, Egypt, by eight potentially toxic elements (PTEs) was investigated in this study. This study considered the absorption of eight PTEs (Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn), and the evaluated P. stratiotes were located in three sampling locations along the Al-Sero Drain, with sampling conducted in both monospecific and homogenous P. stratiotes. Samples of both types of P. stratiotes and water were collected on a monthly basis between May 2013 and April 2014 at each location, utilising three randomly chosen 0.5 × 0.5 m quadrats. Regression models were designed to predict the concentration of the PTEs within the plant’s shoot and root systems. Elevated water Fe levels were correlated with a rise in shoot system Fe concentration, whereas higher Ni concentrations in the water led to a higher Ni concentration within the root system. The latter was also true for Pb. Water Cu levels had a negative association with the Cu concentration within the P. stratiotes shoot system. Raised Fe levels were also correlated with a diminished Fe level within the roots. For all PTEs, P. stratiotes was characterised by a bioconcentration factor of more than 1.0, and for the majority by a translocation factor of less than 1.0. The goodness of fit for most of the designed models, as indicated by high R2 values and low mean averaged errors, demonstrated the associations between actual and predicted PTE concentrations. Any disparity between measured and predicted parameters failed to reach significance with Student t-tests, reinforcing the predictive abilities of the designed models. Thus, these novel models have potential value for the prediction of PTE uptake by P. stratiotes macrophytes inhabiting the Al-Sero Drain. Furthermore, the macrophyte’s constituents indicate the long-term impact of water contamination; this supports the potential future use of P. stratiotes for biomonitoring the majority of the PTEs evaluated in this study.

SHOOT FORMATION OF EPILOBIUM HIRSUTUM L. IN CONNECTION WITH THE ADAPTATION OF HERBS OF THE SEASONAL CLIMATE TO THE CONDITIONS OF VARIABLE HUMIDIFICATION / WATERING

One of the fundamental problems of modern biology is the identification of adaptations of organisms to existence in different environments of the biosphere, the mechanisms and methods of the formation of their adaptations. A comparative analysis of shoot formation and ontogenesis of individuals makes it possible to reveal these features in plant biomorphs, including during the development of reservoirs by herbs by mesophytes. The article describes the shoot formation of the hygromesophyte Epilobium hirsutum L. The development and structural-functional zoning of shoots were assessed from the standpoint of modular organization and compared with the peculiarities of shoots formation in mesophytic and hydrophyte grasses. Shown: their similarity with monocarpic shoots of mesophytic herbs at the initial stages; further prolongation in the form of basipetal development through heterochronies and heterotopies with the development of lateral sylleptic shoots as in hydrophytes; increasing the area of the assimilating surface of an individual and ensuring the autonomy of individual shoot systems due to this with early morphological disintegration of the individual. It is proposed to distinguish the following stages in the development of the terrestrial part of the shoot system: vegetative uniaxial shoot - monocarpic shoot - disjunctive system of monopodial shoot - synflorescence system (double heterothetical frondose-frondular brush) at the shoot apex and replacement shoots in the transitional phase of its development in the zone of renewal , broken by the middle zone of inhibition, is more multicomponent and branched in comparison with those in mesohygrophytes like Veronica longifolia L., but less complexity than in hydrophytes - the aquatic form of V. anagallis-aquatica L. It is noted that the early transformation of the universal module (monocarpic shoot) into the main module (the shoot system formed on its basis) is provided by polyvariance in the development of leaf rudiments and axillary structures of elementary modules (elementary metameres) in connection with the conditions of the location of the apex and demonstrates possible mechanisms of adaptation of flowering plants with a sympodial long-shoot model of shoot formation to life in water bodies: abbreviation of ontogeny of an individual and monocarpity of ramet with polycarpicity of an organism (prolongation of ontogeny of an individual).

First Report of Alternaria arborescens Causing Early Blight on Tomato in Iraq

In this paper, the isolation of the fungal species Alternaria arborescens was done from symptomatic tomato leaves and diagnosed morphologically and molecularly using ITS primers. Subsequently, pathogenicity determination was achieved for the diagnosed fungal species on tomato plant. It’s noteworthy, this work on A. arborescens was not previously recorded as a potential pathogen on the shoot system of tomato in Iraq.

Young Field-grown Kiwifruit Plants’ Response to Early Autumn Frost Injury in Texas

Two-year-old, field-grown golden kiwifruit (Actinidia chinensis) and fuzzy kiwifruit (Actinidia deliciosa) plants were evaluated for injury following an early freeze event of −4.1 °C on 14 Nov. 2018 in Burleson County, TX. Plant material included seven cultivars: one seed-propagated [Sungold™ (ZESY002)] and three cutting-propagated golden kiwifruit (AU Golden Dragon, AU Golden Sunshine, CK03), and one seed-propagated (Hayward) and two cutting-propagated fuzzy kiwifruit (AU Authur and AU Fitzgerald). Observations were made 5 weeks after the frost event. Base trunk diameter (BD) and maximum trunk diameter damaged (MDD) provided a reference of plant size and crude measurement of damage intensity, as evident by presence of water-soaked necrotic and/or dehydrated tissue following the removal of a thin slice of periderm, vascular cambium, phloem, and xylem. Percent of base diameter damaged (PBDD) was calculated as MDD divided by BD and provided an assessment of damage, unbiased by plant size. Percent of shoot damaged (PSD) was visually evaluated as the percentage of entire shoot system exhibiting damage. In addition, presence of basal damage (DB) and basal cracking (CB) were recorded. A strong cultivar response was observed for BD, MDD, PBDD, and PSD. Mean cultivar values for PSD ranged from 79% and 19% for AU Authur and Sungold™ seedlings, respectively, which represented extremes among cultivars. Fuzzy kiwifruit exhibited greater injury (PBDD, PSD, DB, and CB) as compared with golden kiwifruit cultivars. Basal damage and basal cracking proved unique to fuzzy kiwifruit, as DB ranged from 0% in Sungold™ seedlings to 100% in fuzzy kiwifruit ‘AU Authur’ and ‘AU Fitzgerald’. In spite of having greater vigor, golden kiwifruit plants sustained less injury. Method of propagation had no effect on injury. PBDD and PSD proved to be reliable field assays for documenting injury, based on their strong correlation value (r = 0.92). Greater relative autumn frost tolerance of golden kiwifruit over fuzzy kiwifruit cultivars is previously unreported.

Aphelenchoides besseyi Parasitizing Common Bean in Brazil

Aphelenchoides besseyi is the causal agent of soybean green stem and foliar retention syndrome known as Soja Louca II. This nematode has recently been reported parasitizing cotton in Brazil. In Costa Rica, it causes the symptoms known as “amachamiento” and false angular spots in common bean (Phaseolus vulgaris). Due to the great importance of beans to Brazilian agriculture, the objective of this research was to study the pathogenicity of A. besseyi in common bean under greenhouse conditions, including its endoparasitic relationships by staining root and shoot system tissues with fuchsin acid. In addition, A. besseyi was collected and quantified from shoot systems 30 days after inoculation by washing the tissue in water and blender centrifugal-flotation. We observed the symptoms of “amachamiento”, leaf and vein deformation in the expanded trifoliate leaves, and also leaves with necrotic, brown to reddish and angular lesions, characteristics from false angular spot, and deformed stems characterized by enlargement of nodes, retortions and necrotic lesions. High numbers of nematodes were found inside common bean plants. This is the first report of the pathogenicity and symptoms caused by A. besseyi in common bean in Brazil. These findings are important for development of management strategies to avoid losses on bean cropped in infested areas.

Root system influence on high dimensional leaf phenotypes over the grapevine growing season

SummaryIn many perennial crops, grafting the root system of one individual to the shoot system of another individual has become an integral part of propagation performed at industrial scales to enhance pest, disease, and stress tolerance and to regulate yield and vigor. Grafted plants offer important experimental systems for understanding the extent and seasonality of root system effects on shoot system biology.Using an experimental vineyard where a common scion ‘Chambourcin’ is growing ungrafted and grafted to three different rootstocks, we explore associations between root system genotype and leaf phenotypes in grafted grapevines across a growing season. We quantified five high-dimensional leaf phenotyping modalities: ionomics, metabolomics, transcriptomics, morphometrics, and physiology and show that rootstock influence is subtle but ubiquitous across modalities.We find strong signatures of rootstock influence on the leaf ionome, with unique signatures detected at each phenological stage. Moreover, all phenotypes and patterns of phenotypic covariation were highly dynamic across the season.These findings expand upon previously identified patterns to suggest that the influence of root system on shoot system phenotypes is complex and broad understanding necessitates volumes of high-dimensional, multi-scale data previously unmet.

Grapevine microbiota reflect diversity among compartments and complex interactions within and among root and shoot systems

BackgroundWithin an individual plant, different compartments (e.g. roots, leaves, fruits) host distinct communities of microorganisms due to variation in structural characteristics and resource availability. Grafting, which joins the root system of one individual with the shoot system of a second genetically distinct individual, has the potential to bring the microbial communities of different genotypes together. An important question is the extent to which unique root system and shoot system genotypes, when grafted together, influence the microbiota of the graft partner. Our study sought to answer this question by utilizing an experimental vineyard composed of ‘Chambourcin’ vines growing ungrafted and grafted to three different rootstocks, replicated across three irrigation treatments. We characterized bacterial and fungal communities in roots, leaves, and berries, as well as surrounding soil. Our objectives were to (1) characterize the microbiota of compartments within the root system (roots and adjacent soil) and the shoot system (leaves and berries), (2) determine the influence of rootstock genotypes, irrigation, and their interaction on the microbiota of aboveground and belowground compartments, and (3) investigate the distribution of microorganisms implicated in the late-season grapevine bunch rot disease sour rot (Acetobacterales and Saccharomycetes).ResultsCompartments were significantly differentiated in bacterial and fungal richness and composition. Abundance-based machine learning accurately predicted the compartment and differential abundance analysis showed a large portion of taxa differed significantly across compartments. Rootstock genotypes did not differ significantly in microbial community richness or composition; however, individual microbial taxa exhibited significant differences in abundance based on rootstock and irrigation treatment. The relative abundance of Acetobacterales and Saccharomycetes in the berry was influenced by complex interactions among rootstock genotype and irrigation.ConclusionOur results indicate that grapevine compartments retain distinct core microbiota regardless of the rootstock to which they are grafted. While rootstock genotype generally had a subtle impact on global patterns of microbial diversity, we found associations between rootstock genotypes and specific groups of microorganisms. Further experimental validation is needed in order to understand how associations with these microorganisms impacts a vine’s susceptibility to sour rot upon damage and whether the characteristics of wine are impacted.