Structural and functional organization of the root system: a comparative study on five plant species

Plants are affected by soil environments to the same extent that they affect soil functioning through interactions between environmental and genetic factors. Here, five plant species (broad bean, pea, cabbage, fennel, and olive) grown under controlled pot conditions were tested for their ability to differently stimulate the degradation of standard litter. Litter, soil C and N contents were measured for evaluating chemical changes due to plant presence, while soil microbial abundance was evaluated to assess if it had a positive or negative catalyzing influence on litter decomposition. The architecture and morphological traits of roots systems were also evaluated by using specific open-source software (SmartRoot). Soil chemical and microbiological characteristics were significantly influenced by the plant species. Variations in soil C/N dynamics were correlated with the diversity of root traits among species. Early stage decomposition of the standard litter changed on the basis of the plant species. The results indicated that key soil processes are governed by interactions between plant roots, soil C and N, and the microbial metabolism that stimulate decomposition reactions. This, in turn, can have marked effects on soil chemical and microbiological fertility, both fundamental for sustaining crops, and can promote the development of new approaches for optimizing soil C and N cycling, managing nutrient transport, and sustaining and improving net primary production

Garlic (Allium spp.) viruses: detection, distribution and remediation attempts in a European garlic collection

Garlic is an important vegetable crop in numerous countries used as food and natural based medicine. Similar to the majority of vegetatively propagated plants, garlic may be affected by several viruses that can cause severe crop losses. The present study aimed to screen 105 garlic accessions (mother plants) from 5 European countries (Germany, Czech Republic, Poland, Italy, and France) for possible presence of Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV), Garlic common latent virus (GCLV) and Shallot latent virus (SLV). The occurrence of three Allexiviruses (GarV-A, GarV-B and GarV-C) in mixed assays was also investigated. Meristem-tip culture assays were performed in order to attempt eradication of the studied viruses. Garlic viruses identification was made by ELISA and RT-PCR. ELISA outcomes showed that all 105 garlic accessions were infected by different virus combinations. The OYDV and LYSV were identified, by ELISA, in all countries at 96% and 88,6% respectively and by RT-PCR at 99% and 96%. Furthermore, GCLV and SLV were detected by ELISA in about 88% and by RT-PCR at 89% and 90%, respectively with the exception of the studied Allexiviruses which were not amplified by RT-PCR with ALLEX1/ALLEX2 primers. Smaller meristem size (0,3-1,5 mm) led to better virus elimination efficiency (29%) compared to 8% obtained for the larger size (2-2,5 mm). The outcomes were opposite (16% vs. 90%) for plants regeneration. Virus elimination efficiency was linked to the virus type, e.g., OYDV and LYSV were eradicated at 90% while GCLV and Allexiviruses were difficult to eliminate (57,4% and 55,6% of eradication). Given the economic relevance of garlic crops worldwide and the frequently reported incidence of viral infections, it is important to make virusfree germplasm available. Therefore, investigating the garlic germplasm sanitary status and constantly improving it is of crucial importance aiming to increase the overall garlic production

Morpho-anatomical and microbiological analysis of kiwifruit roots with KVDS symptoms

Italy, one of the largest producers of kiwifruit in the world, has lost 10% of its production in recent years because of the spread of the kiwifruit vine decline syndrome (KVDS). Although the aetiology of KVDS has not been characterized, root rot symptoms are often associated with water stagnation and root asphyxia. To investigate causal factors and potential solutions to counter this syndrome, an experimental trial was undertaken in a kiwifruit orchard affected by KVDS in Latina (central Italy) in 2020. Root samples from healthy plants were collected and compared with samples taken from plants affected by KVDS. Macroscopically, the roots affected by KVDS were rotting, showing a loss of rhizodermis and cortical parenchyma. Microscopic analysis revealed damage to the root system with tissue breakdown and decomposition, flaking of the rhizodermis, cortical area with a clear loss of cell turgor, initial decay of the stele and evident detachment of the cortex from the central conducting tissues. Light microscopy, morphological and molecular analyses were carried out on the rhizodermis of roots showing decay and death symptoms. Total DNA extracted from the pure fungal colonies was amplified by PCR with ITS primers, amplicons directly sequenced, and the obtained nucleotide sequences were compared with those present in the GenBank database (NCBI) through BLAST analysis. Genomic analysis allowed the identification of three abundant fungi namely Ilyonectria vredenhoekensis, Fusarium oxysporum and Paraphaeosphaeria michotii. Further investigation is required to determine the role of these fungi in KVDS, whether they are species favoured by water stagnation and root asphyxia; their abundance and presence in other regions, orchards, and kiwifruit species; if they compromise roots functionality individually or conjunction with other microbial pathogens or abiotic factors; and if they contribute to plant death associated with KVDS

Biochemical Characterization and Antimicrobial Activity Against Some Human or Phyto-Pathogens of New Diazonium Heterocyclic Metal Complexes

String of vanadium (IV), zirconium (IV), palladium (II), platinum (IV) and uranium (VI) chelates of 2-cyano-2-[(2- nitrophenyl)hydrazono]thioacetamide (Cnphta) were prepared and characterized by physicochemical, spectroscopic and thermal analyses. The formulae of the isolated solid complexes were assigned as [VO- (Cnphta)2(H2O)]SO4 ·5H2O (1), [ZrO(Cnphta)2(H2O)]Cl2 ·4H2O (2), [Pd(Cnphta)2]Cl2 (3), [Pt(Cnphta)2Cl2]Cl2 (4) and [UO2(Cnphta)2](NO3)2 ·5H2O (5). The infrared assignments clearly showed that Cnphta ligand coordinated as a bidentate feature through the hydrazono nitrogen and the thioacetamide nitrogen for V(IV), Zr(IV) and U(VI) but displayed different behavior for Pd(II) and Pt(IV). Results of the molar conductivities measurements showed that the metal complexes were electrolytes in contrast with Cnphta ligand. The interpretation, mathematical analysis and evaluation of kinetic parameters were also carried out. In addition, the studied ligand and its new chelates were tested for their antimicrobial activity against some human or phytopathogenic microorganisms. The new metal complexes explicated promising antibacterial activity against all tested bacteria especially Staphylococcus aureus and Bacillus subtilis. Regarding the antifungal activity, all metal complexes were able to inhibit the mycelium growth of both tested pathogenic fungi. In particular Zr(IV) and Pt(IV) complexes showed the highest significant fungicidal effect against A. fumigatus similar to positive contro

Selection of elms tolerant to Dutch elm Disease in south-west Romania

Ophoiostoma novo- ulmi continues to be one of the most dangerous invasive fungi, destroying many autochthonous elm forests and cultures throughout the world. Searching for natural genotypes tolerant to Dutch Elm Disease (DED) is one of the main objectives of silviculturists all over the northern hemisphere in order to save the susceptible elms and to restore their ecosystem biodiversity. In this regard, the first trial was established between 1991 and 1994, in south-west Romania (Padurea Verde, Timis, oara), using three elm species (Ulmus minor, U. glabra, and U. laevis) with 38 provenances. A local strain of Ophiostoma novo-ulmi was used to artificially inoculate all elm variants and the DED evolution was observed. Furthermore, in 2018–2021 the trial was inventoried to understand the local genotype reaction to DED in the local environmental conditions after almost 30 years. The outcomes of the present study proved the continuous presence of the infections in the comparative culture and its proximity, but the identified pathogen had a new hybrid form (found for the first time in Romania) between O. novo-ulmi ssp. Americana x O. novo-ulmi ssp. novo-ulmi. Wych elm (U. glabra) was extremely sensitive to DED: only 12 trees (out of 69 found in 2018) survived in 2021, and only one tree could be selected according to the adopted health criteria (resistance and vigour). The field elm (U. minor) was sensitive to the pathogen, but there were still individuals that showed good health status and growth. In contrast, the European white elm (U. laevis) proved constant tolerance to DED: only 15% had been found dead or presented severe symptoms of dieback. Overall, the results of this study report the diverse reactions of the Romanian regional elm genotypes to DED over the last three decades, providing promising perspectives for improving the presence of elms in the forest ecosystems of the Carpathian basin

Assessment of Tomato (Solanum lycopersicum) Landraces for Their Agronomic, Biochemical Characteristics and Resistance to Phytophthora infestans

Genetic diversity in crop plants is the conditio sine qua non for sustainable agriculture and long-term food security. Our research carried out the morphological, agronomic, and physicochemical characterization and resistance to late blight of 35 tomato landraces from seven countries. These landraces have been approved and appear in the Official Catalog of Varieties. The International Plant Genetic Resources Institute (IPGRI) descriptors have been used to describe the tomato’s morphological and agronomic characteristics. For the physico-chemical characteristics, the dry matter, the pH, and the carotenoid content (lycopene, lutein, and β-carotene)) were analyzed. Carotenoids were monitored by high-performance liquid chromatography (HPLC). The results showed that the morphological diversity of landraces was very high. Three landraces of remarkable commercial value have shown increased resistance to late blight caused by Phytophthora infestans, one of the most damaging diseases of tomato. Also, six landraces had a lycopene content exceeding 100 μg/g sample. The carotenoid content ranged between 0.769 (Marmande-FR 166) and 140.328 mg kg−1 FW (Răscruci). The landrace with the highest β carotene content was PT 308 with 65.499 mg kg−1 FW, while the lowest values were registered for Marmande-FR 166 with 0.105 mg kg−1 FW. The present study provides essential information on the morphological and agronomic qualities of these tomato landraces and their lycopene and other carotenoid content. The results are discussed in light of the importance of tomato landraces in meeting the preferences of different producers and consumers, the choice of the most suitable landraces for specific pedoclimatic conditions, and the supply of carotenoid pigment sources for the pharmaceutical industry. Our research responds to humanity’s great global challenges: preserving agricultural biodiversity, protecting the environment by identifying pest-resistant varieties, and also protecting consumer health by finding important sources of antioxidants