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Microbial-based biostimulants containing arbuscular mycorrhizal fungi (AMF), Trichoderma fungi and plant growth-promoting rhizobacteria (PGPR) have been applied in an open-field tomato cultivation. A two-years field experiment (2020-2021) was performed in Southern Italy on “Heinz 1534” processing tomato hybrid, using three commercial formulations characterized by different microbial consortia (MIC: Glomus spp., Rhizophagus spp., Bacillus spp., Streptomyces spp., Pichia spp., Trichoderma spp.; EKO: Glomus spp., Bacillus spp., Streptomyces spp., Pseudomonas spp., Arthrobotrys spp., Monacrosporium spp., Paecilomyces spp., Myrothecium spp., Trichoderma spp.; FID: Glomus spp., Bacillus spp., Trichoderma spp.) and comparing them to untreated control (CTRL). The effect of growing season and microorganism-based treatments on yield, technological traits and functional quality of tomato fruits was assessed. The year of cultivation (Y) affected yield (with lower fruit weight, higher marketable to total yield ratio and higher % of total defected fruits in 2020), and technological components (higher dry matter, total acidity, total soluble solids in 2020). During the first year of the trial, all evaluated treatments (MIC, EKO and FID) enhanced soluble solids content by 10%, on average, compared to CTRL. Sucrose and lycopene contents were influenced both by the microbial-based treatments and the growing season (greater values found in 2021 with respect to the first year). Y factor also significantly affected all evaluated metabolites contents, except for tyrosine, essential (EAA) and branched-chain (BCAAs) amino acids. Over two years of field trial, FID biostimulant enhanced the contents of proteins (+53.71%), alanine (+16.55%), aspartic acid (+31.13%), γ-aminobutyric acid (+76.51%), glutamine (+55.17%), glycine (+28.13%), monoethano-lamine (+19.57%), total amino acids (+33.55), essential amino acids (+32.56%) and branched-chain amino acids (+45.10%) compared to the untreated control. Our findings highlighted the valuable effect of FID microbial inoculant in boosting several primary metabolites (proteins and amino acids) in the fruits of processing tomato crop grown under Southern Italy environmental condi-tions, although no effect on yield and its components was appreciated.

Potato (Solanum tuberosum L.) under Mediterranean climate may be affected by internal brown spot, non-pathogenic disorder of flesh tissues leading to a dramatic depreciation of tubers. Its aetiolog...

Background: Wild rocket (Diplotaxis tenuifolia) is prone to soil-borne stresses under intensive cultivation systems devoted to ready-to-eat salad chain, increasing needs for external inputs. Early detection of the abiotic and biotic stresses by using digital reflectance-based probes may allow optimization and enhance performances of the mitigation strategies.Methods: Hyperspectral image analysis was applied to D. tenuifolia potted plants subjected, in a greenhouse experiment, to five treatments for one week: a control treatment watered to 100% water holding capacity, two biotic stresses: Fusarium wilting and Rhizoctonia rotting, and two abiotic stresses: water deficit and salinity. Leaf hyperspectral fingerprints were submitted to an artificial intelligence pipeline for training and validating image-based classification models able to work in the stress range. Spectral investigation was corroborated by pertaining physiological parameters. Results: Water status was mainly affected by water deficit treatment, followed by fungal diseases, while salinity did not change water relations of wild rocket plants compared to control treatment. Biotic stresses triggered discoloration in plants just in a week after application of the treatments, as evidenced by the colour space coordinates and pigment contents values. Some vegetation indices, calculated on the bases of the reflectance data, targeted on plant vitality and chlorophyll content, healthiness, and carotenoid content, agreed with the patterns of variations observed for the physiological parameters. Artificial neural network helped selection of VIS (492-504, 540-568 and 712-720 nm) and NIR (855, 900-908 and 970 nm) bands, whose read reflectance contributed to discriminate stresses by imaging. Conclusions: This study provided significative spectral information linked to the assessed stresses, allowing the identification of narrowed spectral regions and single wavelengths due to changes in photosynthetically active pigments and in water status revealing the etiological cause.

Wild rocket (Diplotaxis tenuifolia, Brassicaceae) is a baby-leaf vegetable crop of high economic interest, used in ready-to-eat minimally processed salads, with an appreciated taste and nutraceutical features. Disease management is key to achieving the sustainability of the entire production chain in intensive systems, where synthetic fungicides are limited or not permitted. In this context, soil-borne pathologies, much feared by growers, are becoming a real emergency. Digital screening of green beds can be implemented in order to optimize the use of sustainable means. The current study used a high-resolution hyperspectral array (spectroscopy at 350–2500 nm) to attempt to follow the progression of symptoms of Rhizoctonia, Sclerotinia, and Sclerotium disease across four different severity levels. A Random Forest machine learning model reduced dimensions of the training big dataset allowing to compute de novo vegetation indices specifically informative about canopy decay caused by all basal pathogenic attacks. Their transferability was also tested on the canopy dataset, which was useful for assessing the health status of wild rocket plants. Indeed, the progression of symptoms associated with soil-borne pathogens is closely related to the reduction of leaf absorbance of the canopy in certain ranges of visible and shortwave infrared spectral regions sensitive to reduction of chlorophyll and other pigments as well as to modifications of water content and turgor.

Internal brown spot (IBS) is a physiological disorder of potato tubers consisting in the appearance of punctiform and/or enlarged rust-coloured necrosis in parenchymal tissues. The IBS disorder leads to important economic impact and yield depreciation since quality, sensory and processing features of tubers may be highly compromised. Nowadays, the causes of IBS are still debated; however, the combination of several genetic, nutritional and environmental factors seems to have a relevant role in modulation of symptoms. In the current work, IBS occurrences together with skin roughness were monitored in potato tubers of different cultivars harvested in 2 years of field trials under different field conditions (environment, irrigation rate). All three IBS-susceptible cultivars used, Luminella, Majestic and Ricciona di Napoli, showed significant IBS incidence. Importantly, incidence and severity increased with tuber size. Ricciona di Napoli was the cultivar most affected by both IBS and skin roughness. Findings showed a strong positive correlation between IBS and skin roughness, suggesting that suboptimal growth conditions may have affected both physiological disorders. The association between IBS and potato skin roughness may provide new insights for the implementation of non-destructive IBS detection in potatoes.

Processing tomato is an important worldwide horticultural crop. It is generally grown in high-input systems, nevertheless, plant responses to nitrogen fertilization, in terms of the effects on dry matter production and allocation to different plant organs, have yet to be investigated in depth. Moreover, information on the crop marginal net return and global warming potential (as an index of the environmental impact of crop cultivation) at different nitrogen rates is still scarce. Therefore, the aim of this work was to study the effects of different nitrogen rates (0, 50, 100, 150, 200, and 250 kg of N ha&minus, 1) on the agronomic, economic, and environmental aspects of processing tomato grown under conventional management in the Mediterranean area. The results of the two-year trials indicated 200 kg of nitrogen ha&minus, 1 as the best rate, ensuring the highest values of marketable and total yields, brix ton ha&minus, 1, and marginal net return and the lowest global warming potential per ton of marketable yield. However, since plants fertilized with 200 kg of N ha&minus, 1 did not record the highest values of nitrogen use efficiency and nitrogen uptake efficiency, our finding suggest the possibility to select better-performing cultivars for these physiological parameters by adopting specific tomato breeding programs.

Aim of study: For baby-leaf lettuces greenhouse cultivations the absence of weeds is a mandatory quality requirement. One of the most promising and innovative technologies in weed research, is the use of Unmanned Aerial Vehicles (or drones) equipped with acquisition systems. The aim of this study was to provide an estimation of the exact weed amount on baby-sized red lettuce beds using a light drone equipped with an RGB microcamera.Area of study: Trials were performed at specialized organic farm site in Eboli (Salerno, Italy), under polyethylene multi-tunnel greenhouse.Material and methods: The RGB images acquired were processed with specific algorithms distinguishing weeds from crop yields, estimating the weeds covered surface and the severity of weed contamination in terms of biomass. A regression between the percentage of the surface covered by weed (with respect to the image total surface) and the weight of weed (with respect to the total harvested biomass) was calculated.Main results: The regression between the total cover values of the 25 calibration images and the total weight measured report a significant linear correlation. Digital monitoring was able to capture with accuracy the highly variable weed coverage that, among the different grids positioned under real cultivation conditions, was in the range 0-16.4% of the total cultivated one.Research highlights: In a precision weed management context, with the aim of improving management and decreasing the use of pesticides, this study provided an estimation of the exact weed amount on baby-sized red lettuce beds using a light drone.

Greenhouse agriculture, a widespread practice in the Mediterranean basin, is prone to impoverishment in soil organic carbon because of crop removal and high decomposition rate. Open-field experimentation has shown that the addition of biochar, a product of thermochemical conversion of biomass, under a limited concentration of oxygen, increases the soil organic C pool, enhances crop productivity and improves C terrestrial sink. The present study investigates the effect of biochar amendment in a greenhouse environment in a Southern Italy organic farm. Two doses (10 or 20 t ha-1) of biochar from conifer pruning wastes were applied immediately before planting 1-week old plants of pepper (Capsicum annuum L.). Plant growth and crop yield were evaluated six months later, at the end of cultivation, in biochar-treated and in control (without biochar) plots. Soil samples were collected in the same plots immediately after biochar addition and six months later and were analyzed for the following parameters: bulk density, water-holding capacity, pH, electrical conductivity, organic carbon, mineral nitrogen, total microbial biomass and fungal mycelium contents, soil respiration, nitrogen mineralization, potential nitrification, soil suppressiveness to Rhizoctonia solani. A single biochar application caused no apparent damage to the crop; on the other hand, no improvement was observed in crop yield or soil suppressiveness to R. solani. In contrast, the single char application positively affected soil respiration, nitrogen mineralization and potential nitrification. These preliminary results suggest that soil amendment with biochar is a potentially useful practice in greenhouse agriculture, yet further experimentation is necessary to assess optimal amounts for better crop productivity and soil quality.

Twenty-five landraces of the cherry-like tomato named Corbarino, a typical niche product grown in the Sarno valley of the Campania region, have been characterized. The landraces used have been compared to eight cultivars widely spread in the same area of cultivation. The genetic diversity within and between landraces was evaluated through the comparison of DNA fingerprints obtained with (GATA)(4) probe hybridized to TaqI digested genomic DNA. Twenty-two of the Corbarino landraces were homogeneous and were unequivocally characterized by their DNA fingerprints. The others are probably "population varieties" in that within each of them polymorphic DNA fragments were identified. According to the characterization of fruit shapes, four groups were identified. One landrace from each group, harvested at the same ripening degree, was further characterized for yield, fruit quality components, antioxidant activities, and carotenoid contents and compared to Faino F(1) and Tomito F(1) hybrids. The Corbarino landraces were all characterized by high yield, a high level of carbohydrates, and high levels of soluble and total solids. Interestingly, the biotype named ISCI 05 was the most suitable for canning. Landraces ISCI 07 and ISCI 05 gave the highest value of antioxidant activities and carotenoid content. These data, together with previously published results, suggested that ISCI 05 should be proposed for the institution of a Label of Origin.

Common bean (Phaseolus vulgaris) is the most important grain legume and plays a significant role in human nutrition being a major source of dietary protein and representing a rich source of minerals and certain vitamins. Several large germplasm collections have been established, which contain large amounts of genetic diversity, including wild and domesticated species. In this study agronomic, biochemical and molecular characterization of landrace bean named "Fagiolo occhio nero di Oliveto Citra" (Phaseolus vulgaris L.), is described. Seeds were obtained by local farmers and field trials were carried out during years 2009-2010, in the typical cultivation site (Oliveto Citra, Salerno Province), using two different densities of investment. During 2011, in order to evaluate the performance in different environments, field trials were conducted in three localities (Battipaglia, Oliveto Citra and Controne). Data analysis shows good adaptability across locations and similar grain yield using two spacing's of seeds. Morphological characterization and molecular analysis, using AFLP and Minisatellite molecular markers, were performed on ten "biotypes" collected from local farmers. Seeds characterization showed variability on the violet area surrounding the hilum (named as eye) while markers have provided useful information on relationships between biotypes. Biochemical analysis, which includes the contents of protein, minerals and antioxidants, shows how the composition is consistent with respect to other landraces and commercial cultivars. The landrace under study revealed genetic stability and good adaptation to cultivated environment with best performance in the native area. In addition, the bio-agronomic characteristics are in accord with studies reported in literature.

Laboratory tests and field trials were conducted in 2010 and 2011 in Salerno province, Southern Italy, to determine the causal agent(s) of pink rot of roots and bulbs of onion and the effects of soil solarization combined with municipal food waste compost amendment in reducing their infections on bulbs of onion. Three fungi were mainly isolated: Fusarium proliferatum and Fusarium tricinctum on bulbs and roots and Pyrenochaeta terrestris exclusively on roots. P. terrestris produce symptoms on roots, but it was not able to cause damage on unwounded bulbs. F. proliferatum and F. tricinctum were able to induce symptoms when inoculated separately and showed no synergistic effects on severity of symptoms on bulbs. They induced symptoms on roots at a lesser extent. Combined inoculations of P. terrestris with both Fusarium species on roots have not increased symptoms severity of pink rot of onion. This is the first report of F. tricinctum as agent of pink rot of onion bulbs. Two years field trials have been carried out from 2009 to 2011 to evaluate the efficacy of soil solarization, applied alone or in combination with municipal food waste compost amendment, for controlling pink rot of onion bulb caused by F. proliferatum and F. tricinctum. For this purpose, soil solarization, alone and combined with compost amendment, were compared with metham sodium and an untreated control. The results of both trials demonstrated that, in presence of pink rot of onion bulbs, compost amendments, applied after solarization, strongly reduced the efficacy of soil solarization from 68.7% to 16.3% in 2010 and from 76.9% to 4.6% in 2011. Organic amendments applied before soil solarization significantly reduced the efficacy of this technique only in 2011. Significant yield increases were detected at the end of both trials in plots treated with solarization alone, metham sodium and compost applied after solarization. The highest incidence of unmarketable infected plants recorded in plots solarized and then amended with compost was compensated by the increase of bulb size and plant weight. These results demonstrated as the benefits achieved with compost amendments in controlling pink rot of onion are not easily predictable and applicable on large scale.

Rocket salad (Diplotaxis spp., Eruca spp.) is a leafy vegetable rich in health-promoting compounds and widely consumed. In the present study, metabolic profiles of 40 rocket accessions mainly retrieved from gene banks were assessed. Seven glucosinolates (GLSs) and 15 flavonol compounds were detected across genotypes. Dimeric 4-mercaptobutyl-GLS and 4-(β-d-glucopyranosyldisulfanyl)butyl-GLS were the major components of the total glucosinolate content. Flavonols were different between genera, with the exception of isorhamnetin 3,4'-diglucoside. Morphoagronomic traits and color coordinates were also scored. Results showed a negative correlation between color and GLSs, indicating these last as responsible for the increase of the intensity of green and yellow pigments as well as for the darkness of the leaf, whereas agronomic traits showed positive correlation with GLSs. Genetic diversity was assessed using inter simple sequence repeat (ISSR) markers, allowing separation of the accessions on the basis of the species and elucidating the observations made by means of phenotypic data.

The use of integrated pest management is a valid alternative to conventional chemical treatments. This study was carried out to evaluate the effects of Brassica carinata seed meals amendment, combined with solarization, on soil activity and lettuce cultivation. B. carinata seed meals pellets are biofumigant plant tissues originated as byproducts of the biodiesel industry. Microbiological data combined with lettuce production results suggest that, after biofumigation, soil microbial communities change toward a new equilibrium that creates better root plant conditions to improve high lettuce yields. Moreover, Brassica seed meals, combined with solarization, preserved soil microflora against detrimental effects of heating, as revealed by enzymatic and functional analysis.

The main objective of this paper was to study the growth and the yield responses of different vegetable crops to pomace compost and biowaste (source-separated municipal organic fraction) compost and to the increase in their rates. A secondary aim was to assess the efficiency of nitrogen (N) supplied to the crops by the compost rate integrated or not with N fertilisers. Finally, the ability of the two composts to improve the soil organic carbon content was also compared. The research was carried out from July 2009 to June 2011. A comparison was made of treatments resulting from the factorial combination of two composts, two rates of application, and two levels of nitrogen fertiliser. A non-fertilised control was also analysed and a standard mineral fertilisation completed the group of treatments. Cauliflower and potato were harvested after the first compost distribution, and onion and lettuce after the second. Our results indicated that the higher the quantity of olive pomace compost applied the greater the slow release of NO 3 –N for crop needs. This has to be related to the high carbon:nitrogen ratio of the olive pomace compost.The halved rate of N fertiliser added to compost was sufficient to overcome the competition between soil microorganisms and roots for nitrogen, only on the second crop in the annual sequence. The biowaste compost without N fertiliser integration also reduced crop yields, but this was to a lesser degree than that achieved with olive pomace compost and was independent of the rate applied. The halved rate of N fertiliser supplied was able to overcome the problems of nitrogen availability. As a consequence, the nitrogen utilisation efficiency showed a higher recovery of nitrogen from biowaste compost than from olive pomace compost, as well as from the 10 t ha –1 dose (rate 10) of dry matter than from the 20 t ha –1 dose. On the other hand, the soil organic carbon content increased significantly only when the composts were added at doses of 20 t ha –1 .

Carotenoids and flavonoids are the main tomatoes antioxidants, having an important role for human health. This study investigates the effects of different water regime and of the industrial processing on the concentration of these compounds in tomato fruits and in tomato products. Two biotypes of Corbarini small tomatoes were cultivated in the Sarno valley (Salerno. Italy) using three different water regimes. A biochemical characterization of the fresh and of the corresponding canned products was performed. Results show that water regime influenced the antioxidant profile of tomato fruits, with marked differences between the two biotypes. Data obtained highlight that water regime markedly influenced the productivity and the quality of the tomatoes. Results also demonstrated that industrial process increased carotenoids content without causing a significant flavonoids degradation. (C) 2010 Elsevier B.V. All rights reserved.

The covering of crops with plastic screens has increased during last years for their protective capacity against vegetable insect pests and virus. To investigate if crop covering can also affect yield level and fruit nutritional quality, we have compared two small tomato varieties ("Corbarino" and "Faino") cultivated in open field and under high tunnel made by two types of covering tissue: a white, 90% transparent tissue ("anti-aphid net") and a "non-woven fabric" ("t-nt"). The "t-nt", which has a closer mesh than "anti-aphid net", proves to be efficient against both pathogens CMV and TSWV, while the other is only effective against CMV. Both covering tissues led to a 30% average reduction of the light intensity; to a rise of 10% in the production yield; to an increase of fruit weight and to a more uniform size of the fruits with respect to the control. Carotenoids concentration in "Corbarino" increased by about 20% with both types of covering tissues, while it remained unchanged in "Faino". Flavonoids concentration was not affected in both varieties. The data on carotenoids were confirmed by a corresponding increase observed only for "Corbarino" tomatoes in the lipophilic antioxidant activity.