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Photosynthesis in Ranunculus asiaticus L.: characterization in two Mediterranean hybrids under fluorescent white light
No full textRanunculus asiaticus L. is a quantitative long-day species, originating from Mediterranean area, grown in cold greenhouse for cut flowers and potted plants. Flowering in ranunculus is a complex process, strongly steered by the temperature and the photoperiod. Vernalization of rehydrated tuberous roots, used as propagation material, anticipates sprouting and leaf rosette formation and flowering. It is known that the time for flowering and the sensitivity to cold treatment vary in the numerous commercial hybrids, while no information seems to be available on the influence of vernalization on the photosynthetic process.
The aim of the experiment was to investigate the influence of two hybrids, MDR (medium earliness) and MBO (early flowering), and two preparation treatments of tuberous roots, only rehydration (Control, C) and rehydration plus vernalisation (V), on photosynthesis and photochemistry and photosynthetic pigments content in plants grown in pot in growth chamber, under controlled environment.
In control plants, photosynthesis was higher in MDR-C than in MBO-C, while the maximal PSII photochemical efficiency (Fv/Fm) slightly decreased in the first hybrid. MBO-C developed more leaves and a consequent higher plant leaf area.
Compared to only rehydration, vernalization of rehydrated tuberous roots increased the number of leaves and the plant leaf area in both the hybrids. The preparation treatment did not affect photosynthetic rate while it decreased the maximal PSII photochemical efficiency (Fv/Fm) in both the hybrids. A significant interaction was found between the hybrid and the preparation treatment in the content of photosynthetic pigments, which decreased in plants from vernalized tuberous roots compared to those from only rehydrated roots in MDR, while increased with vernalization in MBO
The influence of the hybrid and the preparation procedure of tuberous roots on plant growth and flowering in Ranunculus asiaticus L.
No full textFrom suburb to ‘glocal’ innovation hub: Troisi Park, a potential agro-social plaza to intensify the renewal value of the eastern district of Naples
No full textUrban agriculture can play a key role in achieving environmental, social and economic well-being of neighbourhoods, by activating direct and indirect services and opportunities for citizens and contributing to the requalification of neglected suburban areas of big cities. Troisi Park is one of the larger urban parks of the Metropolitan City of Naples. Accomplished in the 1980s on a brownfield area, nowadays the park is experiencing a decline period. In the framework of the H2020 FoodE project, aiming to create sustainable and resilient City/Region Food Systems, the municipality of Naples in collaboration with the Department of Agricultural Sciences of the University of Naples Federico II will bring new life and essence to this park, and in turn to the surrounding area. Through co-designing and planning activities already in progress, Troisi Park will become a ‘global but local' agro-biodiversity hub. Knowledge, nature and culture en masse will engender job opportunities for disadvantaged-people, beside a space for youths, families and people eager to have a healthy lifestyle, being concurrently part of a sustainable inclusive food system, from food production to consumption. Furthermore, the core area of the park will host a greenhouse cluster for horticultural crop production as well as small allotments to be rented to locals and for educational purposes. Owing to an active and inclusive collaboration between local schools, initiatives, the municipality and the University of Naples Federico II, creating a sustainable future for this district of the city is achievable
Photosynthesis in Ranunculus asiaticus L.: characterization in two Mediterranean hybrids under fluorescent white light
No full textRanunculus asiaticus L. is a quantitative long‐day (LD) flower species, originating from Mediterranean area. Cultivation of this crop for cut flowers has been rising during the last years.
Flowering in ranunculus is a complex process, in which the thermal history of tuberous roots and the photoperiod play crucial roles. Specifically, cold treatments of tuberous roots anticipates sprouting and leaf rosette formation, and flowering. Similarly, LD anticipates flowering, but inhibiting the meristematic activity and reducing the number of flower stems. Based on literature, no information seems to be available for ranunculus about the hormonal balance at the different phenological phases, and on the influence of vernalisation on the hormones involved in flowering, and the effects of exogenous gibberellins is controversial.
The aim of the experiment was to asses, in two hybrids of R. asiaticus, the influence of tuberous roots vernalisation on plant photosynthesis and photochemistry, gibberellic acid (GA3) and indoleacetic acid (IAA) biosynthesis, and flowering earliness and characteristics.
Plants of the hybrids MDR (medium earliness) and MBO (early flowering) (Biancheri Creations, Italy), from rehydrated tuberous roots, were grown in climatic chamber at 18°C, under white fluorescent light (PPFD 170 mol m‐2 s‐1, 16 hours), in a mixture of perlite and peat (70:30 in vol.).
In both the treatments, Control (only rehydration) and Vernalisation (exposure of rehydrated tuberous roots to 3,5 °C for 10 days), GA3 and IAA content was determined on tuberous roots at the sowing, and at the rosette stage. Light saturation curves of photosynthesis were determined at the rosette stage, while instantaneous photosynthetic rate and photochemistry, and chlorophyll content were measured at both vegetative and reproductive stages.
Results provide a useful characterization of photosynthetic performance of ranunculus during plant development. Data on the influence of corm vernalisation on the hormonal profile in tuberous roots will help the comprehension on the process of flowering in this species. These information have physiological and practical value, as cultivation of ranunculus is increasing worldwide
Nutrient accumulation, growth and quality of leafy vegetables in aquaponics system are modulated by supplemental LED lighting
Full text linkAquaponics is a highly efficient production system that relies on the food introduced for fish as the only nutrients input for growing both fishes and vegetables. However, plant ability to absorb nutrients in an aquaponics system may be reduced in the winter months characterised by low evaporative demand (low temperature and radiation) which in turn could cause accumulation of nitrate, nitrite, and ammonia in the water. These by-products are harmful for fishes, forcing growers to renew the water more often. The aim of the study was to evaluate growth, physiological response, nutrient accumulation, and quality of lettuce and curly endive, grown in floating raft recirculating aquaponic system (RAS) combined with tilapia, under natural light (NL) or NL integrated with 16 h of supplemental white LED lighting (IL, PPFD: 173 μmol m‐2 s‐1, daily light integral (DLI), 10 mol m‐2 d‐1). Results show a species-specific response to the lighting regimes. Compared to NL, IL promoted plant growth and nutrient accumulation in both species. Particularly in endive it increased leaf area and induced new leaf formation. Supplemental lighting increased whole plant assimilation capacity by increasing the specific leaf area with no effect on pigments content and photochemical efficiency. However, supplemental lighting decreased the maximal photochemical efficiency (Fv/Fm) in lettuce. The different lighting regimes affected nutrient accumulation and translocation in both leaves and roots. To summarize, curly endive performs better than lettuce in aquaponics. Supplemental lighting can guarantee a stable filtration capacity during the winter season, improving overall system performances and plant qualitative attributes of the tested crops
Supplemental daily light integral by LED light to improve the growth of leafy vegetables in aquaponics system
Full text linkAquaponics is a highly efficient production system that relies on the fish food as the only energy system’s input for growing both fish and vegetables, without chemicals. In Mediterranean climates, during winter, due to the combined effects of low solar radiation and low-temperature levels, plant metabolic activity, growth rate, and nutrient uptake decrease, which may, in turn, cause harmful accumulation of nitrogen compounds for fish in the water. Growers renew the water periodically by discharging nutrients enriched water with severe environmental and economic costs. In winter, aquaponics cultivation cycles can be integrated with supplemental light to guarantee a constant daily light integral (DLI) that could promote plant growth and nutrient uptake. The aim of the study was to evaluate the morpho-physiological response of lettuce (Lactuca sativa L.), escarole endive (Cichorium endivia var. latifolia), and curly endive (Cichorium endivia var. crispum) grown in a floating raft, in combination with tilapia (Oreochromis niloticus L.) in a recirculating aquaponics system (RAS). Plant were grown under natural light (NL) or natural light integrated with 16 h of supplemental white LED lighting (IL, PPFD: 173 μmol m-2 s-1, DLI, 10 mol m-2 d-1). The results showed species-specific morpho-physiological responses, with higher productivity in the endives than lettuce, under both light regimes. Compared to NL, plant biomass and leaf area were promoted under IL, accounting for higher plant photosynthetic rates. IL boosted endive growth, while lettuce leaf expansion and biomass allocation into the canopy were increased. Both lettuce and endives performed well in the adopted RAS system. It appears recommendable to provide a fixed DLI during the winter months to shorten the crop cycle by improving plant growth and nutrient uptake. However, further studies are needed to optimize the lighting application protocols and reduce energy costs too
The role of light quality of photoperiodic lighting on photosynthesis, flowering and metabolic profiling in Ranunculus asiaticus L.
No full textPhotoperiodic light quality affects flowering of long day plants, by influencing the phytochrome photoequilibria (PPE) at plant level, however the most effective light spectrum to promote flowering is still unknown for most the flower crops.
We evaluated the influence of light spectrum of three light sources, with different induced PPE, on photosynthesis, metabolic profiling and plant growth and flowering in two hybrids of Ranunculus asiaticus L., MBO and MDR. Three photoperiodic treatments were compared to natural day length (NL): white fluorescent light (FL, PPE 0.84), LEDs Red:Far Red light at 3:1 ratio (R:FR 3:1, PPE, 0.84), and LEDs Red:Far Red light at 1:3 ratio (R:FR 1:3, PPE 0.63).
Under natural light, net photosynthesis was higher in MDR than in MBO, while photochemistry was similar in the hybrids. Compared to NL, photoperiodic treatments did not affect net photosynthesis, while they promoted the quantum yield of PSII and reduced the non-photochemical quenching. Under NL, plant growth was greater in MBO, while flowering started earlier in MDR and flowers characteristics were similar in the hybrids. Despite the greater sensitivity of MDR plants in terms of metabolism, photoperiodic lighting improved plant growth and reduced the flowering time only in MBO, with a stronger effect under R:FR 3:1 light. MDR plants were characterized by higher soluble sugars, polyphenols, photosynthetic pigments and proteins, while MBO plants by higher starch and amino acid content. The morphological effects of photoperiodic light quality and the hybrid-specific response should be taken into account to optimize lighting protocols in commercial farms
Hydroponic and Aquaponic Floating Raft Systems Elicit Differential Growth and Quality Responses to Consecutive Cuts of Basil Crop
Full text linkBasil crops are appreciated for their distinct flavour and appeal to various cuisines globally. Basil production is mainly implemented in controlled environment agriculture (CEA) systems. Soil-less cultivation (e.g., hydroponic) is optimal for producing basil, while aquaponics is another technique suitable for leafy crops such as basil. Shortening the production chain through efficient cultivation techniques reduces basil production’s carbon footprint. While the organoleptic quality of basil demonstrably benefits from successive cuts, no studies have compared the impact of this practice under hydroponic and aquaponic CEA conditions. Hence, the present study evaluated the eco-physiological, nutritional, and productive performance of Genovese basil cv. Sanremo grown in hydroponic and aquaponic systems (combined with tilapia) and harvested consecutively. The two systems showed similar eco-physiological behaviour and photosynthetic capacity, which were on average 2.99 μmol of CO2 m−2 s−1, equal numbers of leaves, and fresh yields of on average 41.69 and 38.38 g, respectively. Aquaponics yielded greater dry biomass (+58%) and dry matter content (+37%), while the nutrient profiles varied between the systems. The number of cuts did not influence yield; however, it improved dry matter partitioning and elicited a differential nutrient uptake. Our results bear practical and scientific relevance by providing useful eco-physiological and productive feedback on basil CEA cultivation. Aquaponics is a promising technique that reduces chemical fertiliser input and increases the overall sustainability of basil production
Application of LCA methodology to a recirculating aquaponics system (RAS) prototype
Get PDFIn the current scenario of increasing urbanization and food consumption, aquaponic systems are generally regarded as sustainable food production systems. However, its environmental burdens (energy consumption, materials, etc.) were not deeply investigated yet. To assess aquaponics' environmental performance systematically, it is important to take the whole life cycle into account. The aim of this study was to identify and to evaluate the environmental impact of a recirculating aquaponics system (RAS) prototype, using a life cycle assessment (LCA) methodology. Leafy vegetables (i.e., lettuce (Lactuca sativa L.), curly endive (Cichorium endivia var. crispum) and escarole endive (Chicorium endivia var. latifolia)) were grown on floating rafts in combination with tilapia (Oreochromis niloticus L.) at two different lighting regimes (i.e., natural sunlight and natural sunlight integrated with LED supplemental light). Our LCA analysis included four different steps: 1) definition of the goal and scope of the study; 2) life cycle inventory (data collection); 3) life cycle impact assessment (data translation into environmental indicators); 4) interpretation and analysis of the results. Our preliminary results suggest that electricity was the main contributing factor to environmental impact, especially with supplemental light. This LCA study can be useful for providing the groundwork to reduce the potential environmental impact of aquaponics systems
Appraisal of salt tolerance under greenhouse conditions of a cucurbitaceae genetic repository of potential rootstocks and scions
No full textSoil salinization due to climate change and intensive use of water and soil is increasing exponentially. Cucurbitaceae species are cultivated worldwide and the identification of salinity tolerant genotypes to be used as rootstock or scion for securing yield stability in salt affected agricultural areas is a research priority. In the present greenhouse study, we assessed the response to salinity (0 mM a non-salt control and 150 mM NaCl dissolved in the nutrient solution) in the seedlings of 30 genotypes of cucurbits grown in a floating hydroponic system. The species tested included 16 genotypes of Cucumis melo L. (CM1-16), 6 Citrullus vulgaris Schrad. (CV1-6), 2 interspecific hybrids of Cucurbita maxima Duch. × Cucurbita moschata Duch. (CMM-R1 and 2), 4 bottle gourd (Lagenaria siceraria (Molina) Standl. (LS1-4)), 1 Cucurbita moschata Duch. (CMO51-17), and 1 luffa (Luffa cylindrica Mill. (LC1)) species. Results highlighted different morphological and physiological traits between the species and genotypes and a different response to salt stress. We identified C. maxima × C.moscata interspecific hybrid CMM-R2, melon genotypes CM6, CM7, CM10, and CM16 together with watermelon genotypes CV2 and CV6 and bottle gourd LS4 as salt tolerant genotypes and possible candidates as salt resistant rootstock to be introduced in grafting programs
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