Root Zone Sensors for Irrigation Management in Intensive Agriculture

Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method). An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS), such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity) marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy) on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy

Reduction of nutrient run-off by the use of coated slow-release fertilizers on two container-grown nursery crops

The agricultural district of Pistoia (Tuscany, Italy) is one of the most important sites in Europe for the production of Hardy Ornamental Nursery Stock (HONS). One of the main problems of this sector is the environmental impact of the pot cultivation, mainly due to an incorrect irrigation scheduling that leads to high nitrogen and phosphorus losses. The aim of this research has been to compare the effects of the traditional fertigation versus new fertilization strategies, based on the use of controlled slow-release fertilizers (CRFs), on plant growth and on nitrogen and phosphorus run-off in two container HONS species (Photinia × fraseri and Prunus laurocerasus). Every week, plant height, cumulate irrigation and drainage volume were measured on four replicates for each treatment and species. Every four weeks two average samples of drainage water and irrigation water for each treatment and species were analysed, determining total nitrogen and phosphorus content, in order to draft a water and nutrient balance. The three different fertilization strategies did not produce any relevant effect on the final plant height and all plants were ranked in the top quality market category. The data confirmed that the use of CRFs could contribute to a huge reduction of nitrogen and phosphorus run-off in the environment and could be a winning strategy for the fertilization of HONS in nitrate vulnerable zones

Precision agriculture to improve the monitoring and management of tomato insect pests

Human-based monitoring of arthropod pests of agricultural importance is usually a time-consuming and costly activity. The advent of technologies such as automatic traps opens new opportunities for remote monitoring. In this article, we present a novel Artificial Intelligence (AI)-based approach aimed to developing a smart trap for monitoring two major pests of greenhouse tomatoes, namely whiteflies, i.e., Bemisia tabaci and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), and leaf miner flies, Liriomyza spp. (Diptera: Agromyzidae)

Leaf production and quality of sea beet (Beta vulgaris subsp. maritima) grown with saline drainage water from recirculating hydroponic or aquaculture systems

The application of greenhouse soilless culture (or hydroponics) and recirculating aquaculture system (RAS) is rapidly growing worldwide as these technologies provide controlled growing conditions for crop plants and aquatic organisms, thus enhancing productivity. The wastewater from RAS and hydroponics is generally rich in many essential plant nutrients and could be reused for crop irrigation, thus reducing the costs for both wastewater treatment and fertilizers. Many wild edible plant species are salt-tolerant glycophytes or halophytes and hence are suitable for cultivation with saline wastewater in cascade cropping systems or decoupled aquaponic systems. The goal of this work was to investigate the effects of drainage water from semi-closed substrate plant culture or saltwater RAS on leaf production and quality of sea beet plants (Beta vulgaris subsp. maritima) grown hydroponically in a greenhouse. Two experiments were conducted in autumn with plants cultivated in a floating raft system to compare five different nutrient solutions: standard nutrient solution (CNS, control; EC 2.80 dS m−1, Na 0.7 mM); the effluent from a semi-closed substrate culture of tomato used as such (tomato effluent 100%, TE100; EC 6.49 dS m−1, Na 34.9 mM) or diluted (50:50) with CNS (tomato effluent 50%, TE50; EC 4.50 dS m−1, Na 17.8 mM); the effluent from a saltwater RAS with gilthead sea bream, used as such (aquaculture effluent 100%, AE100; EC 42.00 dS m−1, Na 408.6 mM) or diluted (50:50) with CNS (aquaculture effluent 50%, AE50; EC 25.40 dS m−1, Na 204.6 mM). In both experiments, leaf production was significantly reduced in plants grown with AE50 (−46.8%, on average) and AE100 (−70.4%, on average) compared to CNS; on the contrary, no or minor differences were found between CNS, TE50 and TE100 plants. The reduction of crop yield was due to the higher salinity and not to abnormal concentration of some mineral nutrients in AE. In the first experiment, the use of TE and AE also resulted in higher leaf antioxidant capacity and concentration (both expressed on a fresh weight basis) of total chlorophylls, carotenoids, flavonoids, and phenols. In both experiments, leaf concentration of Na and oxalate (both total and soluble) significantly increased with the salinity of the nutrient solution. Due to the less favourable light conditions, leaf nitrate concentration was much higher in the second experiment than in the first one, regardless of the nutrient solution. In conclusion, sea beet could be grown using hydroponic wastewater with moderate salinity with no or minor effect on leaf production and quality. In contrast, the use of highly saline aquaculture effluents markedly reduced crop yield and negatively affected leaf quality due to increased concentration of sodium, oxalate, and nitrate. In general, sea beet leaves were high in oxalate and their consumption should be limited

A deep learning-based pipeline for whitefly pest abundance estimation on chromotropic sticky traps

Integrated Pest Management (IPM) is an essential approach used in smart agriculture to manage pest populations and sustainably optimize crop production. One of the cornerstones underlying IPM solutions is pest monitoring, a practice often performed by farm owners by using chromotropic sticky traps placed on insect hot spots to gauge pest population densities. In this paper, we propose a modular model-agnostic deep learning-based counting pipeline for estimating the number of insects present in pictures of chromotropic sticky traps, thus reducing the need for manual trap inspections and minimizing human effort. Additionally, our solution generates a set of raw positions of the counted insects and confidence scores expressing their reliability, allowing practitioners to filter out unreliable predictions. We train and assess our technique by exploiting PST - Pest Sticky Traps, a new collection of dot-annotated images we created on purpose and we publicly release, suitable for counting whiteflies. Experimental evaluation shows that our proposed counting strategy can be a valuable Artificial Intelligence-based tool to help farm owners to control pest outbreaks and prevent crop damages effectively. Specifically, our solution achieves an average counting error of approximately compared to human capabilities requiring a matter of seconds, a large improvement respecting the time-intensive process of manual human inspections, which often take hours or even days

Green roofs and green façades for improving sustainability of towns

Nowadays, buildings in Europe account for a consumption of 40% of total energy use and about 65% of total electricity consumption. According to the European Directive on the energy performance of buildings (EPBD Directive), solutions such as green roofs and green walls can help to reduce energy consumptions and the greenhouse gases emissions by buildings. The installation of plant systems covering some surfaces of the building allows to reach an improvement of the building's energy efficiency mainly by reducing the energy demand for cooling in warm periods. The green layers used for buildings contribute to improve thermal insulation, since they reduce the direct solar radiation while the evaporative cooling contributes to create a better local microclimate. This paper provides the first data collected by a green wall prototype in progress at ENEA Casaccia Centre to investigate the effects of this natural green solution on the energy efficiency of buildings. The project was funded by the Programme Research of Electrical System, and is being carried out in cooperation with the Universities of Pisa, Bari and Viterbo

Effects of Nonthermal Plasma (NTP) on the Growth and Quality of Baby Leaf Lettuce (Lactuca sativa var. acephala Alef.) Cultivated in an Indoor Hydroponic Growing System

The aim of this research was to develop an effective protocol for the application of nonther-mal plasma (NTP) technology to the hydroponic nutrient solution, and to investigate its effects on the growth and quality of baby leaf lettuce (Lactuca sativa var. acephala Alef.) grown in a hydroponic growing system (HGS) specifically designed for indoor home cultivation. Four HGSs were placed in separate growth chambers with temperature of 24 ± 1◦ C and relative humidity of 70 ± 5%). Lettuce plants were grown for nine days in nutrient solutions treated with NTP for 0 (control) to 120 s every hour. Results of the first experiments showed that the optimal operating time of NTP was 120 s h−1 . Fresh leaf biomass was increased by the 60 and 120 s NTP treatments compared to the control. Treating the nutrient solution with NTP also resulted in greater leaf content of total chloro-phylls, carotenoids, total phenols, and total antioxidant capacity. NTP also positively influenced chlorophyll a fluorescence in Photosystem I (PSI) and photosynthetic electron transport. These results revealed that the NTP treatment of the nutrient solution could improve the production and quality of hydroponically grown baby leaf lettuce

Comparison of three domestications and wild-harvested plants for nutraceutical properties and sensory profiles in five wild edible herbs: Is domestication possible?

In this study, five wild edible herbs traditionally consumed in the Tuscany region (Italy) were evaluated for their potential in human nutrition. The nutraceutical characterization of Rumex acetosa, Cichorium intybus, Picris hieracioides, Sanguisorba minor, and Plantago coronopus, as well as their sensory profile were reported. Additionally, a preliminary assessment of completely different domestication of the wild species (named "soilless", pot, and open field) was conducted to verify the possibility of their marketability, which is impossible if the plants are only gathered as wild. The open field domestication allowed to obtain plants with nutraceutical and sensory profiles similar to those of the wild species, especially in C. intybus, P. hieracioides, and S. minor. The pot domestication allow to obtain plants with chlorophyll and carotenoid contents close to those of the wild species, as well as a lower total phenolic and flavonoid content and ascorbic acid content than wild species. In the "soilless"method, R. acetosa and P. coronopus exhibited a high quality in terms of phytochemicals and antioxidant activity. Afterward, the sensory profile was strongly affected by the domestication in terms of the palatability, except for R. acetosa and P. coronopus, which displayed Hedonic Index (HI) values close to the consumer acceptability limit (HI = 6). A sensory profile similar to that of wild species was reported in open field domestication, whereas a worse sensory profile was reported in P. hieracioides and C. intybus domesticated using the soilless method. Finally, according to the preliminary assessment carried out in this study through an analysis of the general nutraceutical properties, S. minor was shown to be the most promising species thanks to its intrinsically highest nutraceutical properties considering the marketability of wild edible herbs as "new"functional food. However, further research on the bioavailability and bioactivity tests of nutraceutical compounds present in this species are required to confirm the findings of this study