Effects of organic fertilization from wet olive pomace on emmer wheat (Triticum dicoccum Shrank) grain yield and composition

In a circular economy framework, the evaluation of waste by-product use as fertilizer is essential to promote sustainable agriculture. Olive oil wet pomace can be a valuable alternative as organic fertilizer on cereal crops. Aim of the study is to evaluate the effects of organic (with olive oil waste pomace) fertilization, on grain yield, protein and polyphenol content of emmer wheat grown in Southern Italy. Different amounts, time and amount of application of organic fertilizer were compared to a traditional mineral fertilizer treatment. The chemical analysis, mainly grain protein content and phenolic acids contents, were carried out on the hulled seeds. Agronomic traits showed that the application of olive wet pomace at 140 Mg ha−1 in the first year and 70 Mg ha−1 in the second year, gave the best grain yield than an annual amount application of 70 Mg ha−1. No difference between organic and mineral fertilization was observed when the latter was carried 1 or 2 years before, and the organic fertilization increased grain protein content respect to mineral one. Polyphenol content was not significantly affected by fertilization treatments, while ferulic acid in the emmer grain recently fertilized with wet pomace showed a higher content than emmer fertilized 2–3 years before

Short-term soil amendment by sewage sludge anaerobic digestate in a tomato monoculture suppresses Fusarium vascular wilt disease by changing the taxonomic characteristics of soil microbiota

Digestate incorporation into topsoil determines soil fertility improvement by changing composition and structure of soil microbiota. However, how microbiota responds to short-term soil amendment by sewage sludge anaerobic digestate (SSD) for suppressing Fusarium vascular wilt disease is unknown. This study compares the effects of three SSD-based treatments to suppress Fusarium oxysporum f. sp. lycopersici (Fol) in a long-term cherry tomato monoculture under field condition in a 3-year trial. Three sampling sites with two application times (two bulk soils at 3–12 weeks after amendment and one tomato rhizosphere soil at 12 weeks post-amendment) were chosen. Three digestate typologies (liquid, centrifuged, and dried) having physicochemical features and heavy metals content below the legal limits were tested at 50 l, 3.5 kg and 2.5 kg m−2y−1 dose, respectively. Fusarium wilt disease was measured for three consecutive years by severity index and Fol abundance in tomato vascular tissue was assessed by ITS rDNA gene sequencing. Fol abundance and taxonomic structure of Fusarium community in the rhizosphere were determined at specie level at the end of the trial by ITS rDNA and EF1α rDNA genes sequencing, respectively. The taxonomic structure (α-, β-diversity) of soil bacterial community (SBC) was characterized from phylum up to genus level at the end of the trial in all the sites by 16S rRNA gene sequencing. The results showed that dry SSD reduced disease severity in field up to 18 % and Fol abundance in tomato up to 0.9 ITS copies g−1 tissue. Fol abundance was decreased in the rhizosphere up to 0.0027 ng μl−1 DNA, while the Fusarium community shifted between treated-soils and un-amended. The SBC composition (α-diversity) changed in the rhizosphere by applying dry digestate, while the SBC structure (β-diversity) shifted either among treatments or sites. Bacterial members related to Fol suppression (Bacillus, Chitinophaga, Flavihumibacter, Flavobacterium, Pseudomonas and Terrimonas) increased in the rhizosphere (P < 0.01, P < 0.001) more than in the bulk soils by applying both dewatered-SSDs. Thus, digestate soil amendment carried out for three consecutive years has affected tomato Fusarium wilt severity by changing the taxonomic characteristics of fusaria and bacteria communities of the amended soil

Maize Yield Response, Root Distribution and Soil Desiccation Crack Features as Affected by Row Spacing

Plant density is among the most critical factors affecting plant yields and resource use efficiency since it drives the exploitation of the available resources per unit area, root distribution and soil water losses by direct evaporation from the soil. Consequently, in fine-textured soils, it can also affect the formation and development of desiccation cracks. The aim of this study, carried out on a sandy clay loam soil in a typical Mediterranean environment, was to investigate the effects of different row spacings of maize (Zea mais L.) on yield response, root distribution and the main features of desiccation cracks. The field experiment compared bare soil and soil cropped with maize using three plant densities (6, 4 and 3 plants m−2), obtained by keeping the number of plants in a row constant and varying the distance between the rows (0.5–0.75–1.0 m). The highest kernel yield (16.57 Mg ha−1) was obtained with the greatest planting density (6 plants m−2) with a row spacing of 0.5 m; significantly lower yields were recorded with spacings of 0.75 and 1 m, with a decrease of 8.09% and 18.24%, respectively. At the end of the growing season, soil moisture in the bare soil was on average 4% greater in comparison to the cropped soil and was also affected by row spacing, decreasing with the decrease in the inter-row distance. An inverse behaviour was observed between soil moisture and both root density and desiccation crack size. Root density decreased to the increase in soil depth and to the increase in distance from the row. The pluviometric regime occurred during the growing season (total rainfall of 343 mm)-resulted in the formation of cracks of reduced size and with an isotropic behaviour in the bare soil, whereas in the cultivated soil, the cracks were parallel to the maize rows and increased in size with decreasing inter-row distance. The total volume of the soil cracks reached a value of 135.65 m3 ha−1 in the soil cropped with a row distance of 0.5 m, and was about ten times greater in comparison to the bare soil and three times greater in comparison to a row spacing of 1 m. Such a volume would allow a recharge of 14 mm in the case of intense rainy events on soil characterised by low permeability

Durum Wheat Response to Organic and Mineral Fertilization with Application of Different Levels and Types of Phosphorus-Based Fertilizers

The use of green compost is a suitable technology to recycle organic waste into environmentally friendly soil improvement mitigating the pressure on landfills and contributing to sustainability. Among the major nutrients, phosphorus (P) stands at a significant position for seed and fruit quality, photosynthesis, and metabolic function in plants. This work evaluates the effects of different doses of mineral/organic fertilizers on two durum wheat cultivars: Anco Marzio and Vespucci. The fertilization trials compared one unfertilized control test and six treatments performed with different types of fertilizers (four minerals and two organics, based on green compost). Grain yield, compared with the unfertilized control, increased with the mineral fertilization by 125.5% for Anco Marzio and 136.42% for Vespucci, while organic fertilization alone determined an increase of 25.52% and 30.92% for Anco Marzio and Vespucci, respectively. The contribution of a higher dose of phosphorus (140 kg ha−1), combined with nitrogen and potassium, favored a further increase in grain production (+9.34%), compared with 100 kg ha−1. The content of chlorophylls and carotenoids was highly increased (5%) in both the cultivars by all kinds of phosphate fertilization, whereas an increase in the phosphate content of caryopses resulted in Anco Marzio across the two years but not in Vespucci. Among the two cultivars of durum wheat, Vespucci produced a greater quantity of grains but with a less vitreous consistency and poorer in proteins than Anco Marzio. The fertilization management also influenced the wheat behavior to stripe yellow rust attack by showing the highest index severity with the compost-based fertilization. The best management of fertilizers associated with the use of more phosphorus-use-efficient genotypes, are essential for improving quality and for the development of a sustainable agriculture

Exploring Aegilops caudata: A Comprehensive Study of the CslF6 Gene and β-Glucan

In the quest for sustainable and nutritious food sources, exploration of ancient grains and wild relatives of cultivated cereals has gained attention. Aegilops caudata, a wild wheatgrass species, stands out as a promising genetic resource due to its potential for crop enhancement and intriguing nutritional properties. This manuscript investigates the CslF6 gene sequence and protein structure of Aegilops caudata, employing comparative analysis with other grass species to identify potential differences impacting β-glucan content. The study involves comprehensive isolation and characterization of the CslF6 gene in Ae. caudata, utilizing genomic sequence analysis, protein structure prediction, and comparative genomics. Comparisons with sequences from diverse monocots reveal evolutionary relationships, highlighting high identities with wheat genomes. Specific amino acid motifs in the CslF6 enzyme sequence, particularly those proximal to key catalytic motifs, exhibit variations among monocot species. These differences likely contribute to alterations in β-glucan composition, notably impacting the DP3:DP4 ratio, which is crucial for understanding and modulating the final β-glucan content. The study positions Ae. caudata uniquely within the evolutionary landscape of CslF6 among monocots, suggesting potential genetic divergence or unique functional adaptations within this species. Overall, this investigation enriches our understanding of β-glucan biosynthesis, shedding light on the role of specific amino acid residues in modulating enzymatic activity and polysaccharide composition

Green compost influences yield and quality of carrots (Daucus carota L.) by enhancing root rot suppression to Sclerotinia sclerotiorum (Lib. De Bary)

The aim of this research, carried out in Bari and Policoro (Southern Italy) from March to June 2018, was to evaluate the effects of two different green composts on yield, quality, and root rot suppression of carrot (Daucus carota L.) cv. Rubrovitamin when compared to a mineral fertilizer and a plant growing media of peat-pumice. Green composts obtained from the municipal solid waste (Biovegetal) and olive pomace by olive mill were used in outdoor crop as fertilizer to enhance root yield and quality and in glasshouse to evaluate root rot suppression against Sclerotinia sclerotiorum. A randomized complete block design with six replicates was used. A total of eight treatments was compared in outdoor (mineral fertilization, three levels of each compost and unfertilized control). A total of five treatments was used in glasshouse: carrot was cropped in a growing media made of peat and pumice and fertilized with the two composts at two different levels, compared to an un-sterile potting mix of 60% peat with 40% pumice used as control. In the carrot grown outdoors the different composts did not influence either the length of the phenological phases or the entire crop cycle, but the highest dose of olive pomace (30 Mg ha-1) favored the greatest root production with an increase of 19.9% if compared to the mineral fertilizer. Biovegetal at the highest dose (30 Mg ha-1) provided non-statistically differences in root production from that obtained with the mineral fertilization, as well as the lowest rate (15 Mg ha-1) of composted olive pomace supplemented with 50 kg N ha-1. The highest carotenoids content, total soluble solids and specific weight were recorded by the amendment with the highest composted olive pomace rate. Concerning the root rot suppression effect, Biovegetal showed to be more effective than composted olive pomace. Thus, the use of green compost could represent a useful alternative to mineral fertilization and soil-borne disease control by synthetic fungicides through an adding-value due to by-products reusing and waste recycling

Spatial distribution of roots and cracks in soils cultivated with sunflower

The aim of this research was to investigate the spatial distribution of roots and cracks in two clay soils cropped with sunflower under different inter-row spacing in order to identify the optimal management. A latin square experimental design was applied to compare bare soil and soil cropped with sunflower, with three plant densities, obtained by keeping constant the number of plants on the row (3 plants m−1) and varying the row spacing (0.4, 0.6, 0.8 m). The presence of the crop and the different distance between rows influenced soil moisture content as well as the root spatial distribution and thus the structural features of cracks. Increasingly lower values of moisture were found in both soils as the distance between rows decreased; an opposite trend was observed for both root density and crack size. The volume of cracks in the soil grown with sunflower at 0.4 m row spacing was 201.4 m3 ha−1, thus 8 times higher than the value on the bare soil and 2.5 times higher compared to the one grown at 0.8 m between rows. Optimal results in terms of root density, soil moisture and crack size were obtained with an inter-row spacing of 0.6 m

Study of variability of β-glucan in wheat genotypes

Wheat is one of the most important cereal crops worldwide, used for the production of bread and pasta. To improve the quality of wheat-based foods, several breeding programs have been carried out, focusing on the content of proteins, pigments, antioxidants and, more recently, fiber.Peer reviewe

Is the CslF6 gene involved in the accumulation of (1,3;1,4)-β-D-glucan in wheats, their wild relatives and their hybrids?

Mixed linkage (1,3;1,4)-β-d-glucan (MLG) is a well-recognized bioactive carbohydrate and dietary fibre with expanding applications in food industry. The MLG are small components of the cell wall of vegetative tissues of cereals synthetized by members of the Cellulose Synthase-Like genes (Csl). Within the family, the CslF6 has been the major contributor in wheat. It is of significant health and economic benefits to enhance MLG content in wheat, a staple grain with naturally low MLG levels. This study investigated the role of CslF6 gene in MLG synthesis and analysed total MLG contents, cell wall monosaccharide, glycosidic linkage composition, and profile of major comprising oligosaccharides of MLG in various wheat genotypes, their wild relatives (Aegilops caudata and Dasypyrum villosum), and hybrids between them. We observed a relationship between CslF6 gene expression and MLG accumulation across the different wheat lines. While Aegilops caudata and Dasypyrum villosum exhibited higher MLG content than other genotypes, hybrid breeding led to an increase in MLG content by 24.4% in durum wheat and 43.3% in T. aestivum. Variations in the ratios of major oligosaccharides released from MLG by lichenase treatment and in the compositions of cell wall monosaccharides and glycosidic linkages were also found. This study demonstrates that HPAEC-PAD and GC–MS-based glycomics are invaluable tools to assist breeders in selecting high MLG lines.QC 20240722</p