Recipient Organization
RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY
65 BERGEN ST
NEWARK,NJ 07107
Performing Department
(N/A)
Non Technical Summary
The agricultural sector is faced with great challenges brought about by climate change and population growth including water scarcity and agrichemical delivery inefficiencies. Water scarcity is a pressing issue in agriculture, leading to low yields and crop failures whereas inefficiencies in agrichemical delivery also result in major environmental and public health issues. There is an urgent necessity to develop effective irrigation strategies, which utilize minimal water usage and optimize the delivery of agrichemicals for crop growth. To this effect, in this project we propose the development of an electrospray/electrospinning-based interdisciplinary approach termed "Electroponics' which can be used for the precise delivery of water and nutrients in a soilless setting, coupled with seeds coated with electrospun nanofibers made from sustainable nature derived biopolymers which can optimize the agrichemical delivery and plant growth. A scaled-up electroponics system will also be developed and assessed in a field study in terms of its ability to enhance plant growth using minimal amounts of water and agrichemicals.The proposed innovative platform for the precision delivery of water and agrichemicals using electrospray/electrospinning approaches which can be used as an alternative tohydroponics/aeroponics can be used in urban agriculture systems, and can be a game-changing approach that can help in both climate resiliency and food security. The scientific knowledge gained in the project can impact and inform more efficient farm practices and enhance food security at a global scale.
Animal Health Component
50%
Research Effort Categories
Basic
25%
Applied
50%
Developmental
25%
Goals / Objectives
The main AIMS/Goals of the project are as follows:AIM 1:Development of an electrospray/electrospinning platform for precision water and agrichemical delivery: In this aim, we will endeavor to develop a platform termed as 'Electroponics' by combining two approaches: seeds coated with electrospun nanofibers for release of micronutrients (see below) and electrospray deposition (ESD) of water and agrichemicals (see below). Plant growth studies will also be carried out to demonstrate the feasibility of a lab scale Electroponics system. In more detail:Development of Electrospun Nanofiber Seed Coatings for "Smart" Release and Delivery of Agrichemicals:? In order to optimize agrichemical delivery and enhance plant growth, the delivery and release of the agrichemicals will be optimized using electrospinning-based seed coating methods using nature derived biopolymers such as cellulose acetate, chitosan (polysaccharides)gelatin, zein(proteins). Out of the four biopolymers listed, the polymer/polymer mix with the optimum release kinetics will be chosen for coating the seeds.Both micronutrients and macronutrients will be used as model agrichemicals in the project.Tuning nanofiber properties by changing electrospinning parameters:The properties of polymer solution (such as solvents and polymer(s) concentrations) and the operational parameters (such as needle-collector distance, applied voltage, fluid flow rate) will be systematically modified in order to optimize the size, cone-jet stability, and morphology of the final nanofibers and ultimately also control the release kinetics of agrichemicals.Physicochemical characterization of nanofibers:Physicochemical characterization including morphology, surface wettability, specific surface area, chemical composition, and crystallinity of the agrichemical-loaded nanofibers will be performed using state of the art analytical methodsRelease kinetics assessment:The synthesized nanofibers containing the agrichemical cocktail will be analyzed for their chemical composition using relevant ICP-MS. Samples from the release studies in aqueous suspension will be acidified and analyzed by ICP-MS for micronutrient, P, or K content. Nitrogen content will be measured using a Nitrogen Determinator after subtracting the baseline of the pure polymer.Nanofiber coated seeds:Layer-by-layer wrapping will be applied to directly coat model seeds with nanofibers. Specifically, a nanofiber layer will be first electrospun on aluminum foil, and the seeds will then be placed on top of this fiber layer; finally, another nanofiber layer will be sprayed onto the seeds. A circular punch (diameter=5 mm) will be used to cut the coated seed overlay into individual seeds. It is worth noting that both the agrichemical concentration in nanofiber and/or the mass of the electrospun nanofiber coating can be modified to obtain desired levels of analyte per seed. Such agrichemical concentration levels per seed are expected to be application and seed specific. Therefore, the analyte or cargo amount per seed can be adjusted for different types of seeds that may have different nutritional requirements.Electrospray delivery of water and agrichemicals (ESD): A single needle ESD module will be developed and assessed for delivery of water and agrichemicals. The seeds are placed in growth media (rockwool plug) and placed in an electrically grounded mesh; A root capillary support is placed under to support root growthFor the proposed studies we will try different flowrates and voltages to determine those that lead to optimal plant growth. In addition, a water saturation sensor (Figure 2) will be explored as a means to control the water/nutrient cycle which can be plant specific and provide valuable data for automation which will be used inAIM-2for the development of a scale up system.Size and charge characterization of ESD droplets:To correlate the growth results with the ESD droplet properties, state-of-the-art real time and integrated instrumentation, which has been utilized in our earlier preliminary studies, will be used to characterize the ESD spray.Plant species and agrichemical nutrient solution selection for plant studies:Bibb lettuce (Lactuca sativa L.) and dwarf tomatoes (Solanum lycopersicum) will be utilized in this study. Bibb lettuce is fast-growing, and it typically needs between 35-40 days to reach maturity in the greenhouse.The nutrient solution we will employ will be the standard 10-5-14 nutrient mix (MaxiGro, GH Inc.), adjusted with calcium hydroxide to achieve the desired pH. The MaxiGro is an NPK fertilizer, with the largest nutrient components being Nitrate Nitrogen (Nitrogen), Phosphate (Phosphorous) and Potash (Potassium). Nutrient analysis, as described below, will be conducted on all grown plants and may lead us to supplement or modify the nutrient mix to eliminate deficiencies and excesses since these mixes are optimized for existing growingNutrient delivery measurement for plant studies:For the plant growth trials, each reported trial will consist of an individual plant that will be harvested at the end of the trial period. All water use efficiency measurements will be repeated in triplicate, and selected plants will be sent for nutrient analysis.AIM 2: Development of a scale-up Electroponics prototype for field testingIn this aim based on the data of the single module lab based electroponics system described above (AIM-1), we will develop a scaleup fully automated electroponics system suitable for plant growth studies (AIM-3). We will implement minimal monitoring to enable complete automation of the Electroponics process via software and sensors.AIM 3: Field testing assessment of the efficacy of the Electroponics scaleup prototype for germination and crop developmentThe Electroponics scaleup prototype developed inAim 2will be utilized for greenhouse studies using two model plants.Various growth/performance parameters will be measured and compared to a traditional hydroponics system. The crop species will consist of cohorts of the two crops demonstrated inAim 1,namely Bibb Lettuce and dwarf tomato.Control plant groups:Two types of control plant groups will be utilized for each plant cohort: a) A panel of 16hydroponicallygrown plants with nanofiber coated seeds and b) 16hydroponicallygrown plants with cnon-nanofiber coated seeds.Water and nutrient use:For the duration of the plant growth, we will monitor and measure the use of water and nutrients for the electroponically grown plants and the control groups using the conventional hydroponic approach.Physiological, biochemical and molecular endpoints for the plants:For the plants grown in greenhouse conditions, various endpoints relevant to healthy plant growth will be assessed.
Project Methods
Development of Electrospun Nanofiber Seed Coatings for "Smart" Release and Delivery of Agrichemicals (AIM-1)Biopolymers: Various naturally derived biopolymers will be utilized as candidates for nanofiber synthesis. The candidates selected for this study are cellulose acetate, chitosan (polysaccharides) and gelatin, zein(proteins). Out of the four biopolymers listed, the polymer/polymer mix with the optimum release kinetics will be chosen for coating the seeds.Agrichemicals: Both micronutrients and macronutrients will be used as model agrichemicals in the project. Micronutrients are important to crop growth, hence as a model micronutrient, copper (Cu) will be used. Macronutrients to be used in the agrichemical cocktail will be in the form of the commercially available MaxiGro 10-5-14 nutrient mix.Solution preparation: Wise selection of solvents and polymers is needed to produce nanofibers through a "green" synthesis strategy. In order to fit within the scope of sustainable agriculture, toxic organic solvents typically used in electrospinning will be avoided in our project. Acetic acid and others "Generally Recognized as Safe" (GRAS) by the US Food and Drug Administration (FDA) will be selected as the solvent to dissolve the biopolymers and agrichemicals. Selected agrichemicals will be incorporated into nanofibers by direct solution integration in the biopolymer solution.Tuning nanofiber properties by changing electrospinning parameters: The properties of polymer solution (such as solvents and polymer(s) concentrations) and the operational parameters (such as needle-collector distance, applied voltage, fluid flow rate) will be systematically modified in order to optimize the size, cone-jet stability, and morphology of the final nanofibersPhysicochemical characterization of nanofibers: Physicochemical characterization including morphology, surface wettability, specific surface area, chemical composition, and crystallinity of the agrichemical-loaded nanofibers will be performed using state of the art analytical methodsRelease kinetics assessment: The synthesized nanofibers containing the agrichemical cocktail will be analyzed for their chemical composition using ICP-MS. Nitrogen content will be measured using a Nitrogen Determinator after subtracting the baseline of the pure polymer.Nanofiber coated seeds: Layer-by-layer wrapping will be applied to directly coat model seeds with nanofibers. Specifically, a nanofiber layer will be first electrospun on aluminum foil, and the seeds will then be placed on top of this fiber layer; finally, another nanofiber layer will be sprayed onto the seeds. A circular punch (diameter=5 mm) will be used to cut the coated seed overlay into individual seeds.Electrospray delivery of water and agrichemicals (ESD) (AIM-1)Methods: A single needle ESD module will be developed and utilized. The seeds are placed in growth media (rockwool plug) and placed in an electrically grounded mesh; A root capillary support is placed under to support root growth. By adjusting the flowrate and voltage, the surface tension and electrical conductivity of the nutrient solution a stable cone-jet spray is established.Electrospray parameters and approach: For the proposed studies we will follow the approach offsetting different flowrates and voltages to determine those that lead to optimal growth. Once the optimal flowrate is determined, we will additionally evaluate the number of watering cycles between 1 and 10 to see if there is an advantage to intermittent ESD delivery. In addition, a water saturation sensor will be explored as a means to control the water/nutrient cycle.Growth media and capillary support: To allow for a wide range of crops, we will design a root support and media system that can integrate seeds with reusable, low form factor supports.Size and charge characterization of ESD droplets: To correlate the growth results with the ESD droplet properties, state-of-the-art real time and integrated instrumentation, which has been utilized in our earlier preliminary studiesPlant species and agrichemical nutrient solution selection for plant studies: Bibb lettuce (Lactuca sativa L.) and dwarf tomatoes (Solanum lycopersicum) will be utilized for the study. Seeds will be purchased from commercial suppliers and will be coated as described above. The nutrient solution we will employ will be the standard 10-5-14 nutrient mix (MaxiGro, GH Inc.), adjusted with calcium hydroxide to achieve the desired pH. The MaxiGro is an NPK fertilizer, with the largest nutrient components being Nitrate Nitrogen (Nitrogen), Phosphate (Phosphorous) and Potash (Potassium). Nutrient analysis, as described below, will be conducted on all grown plants and may lead us to supplement or modify the nutrient mix to eliminate deficiencies and excesses since these mixes are optimized for existing growing methods.Experimental conditions for plant studies: All ESD sprays will be conducted in the cone-jet mode, which requires application of 7-10 kV by an HV source in the root zone with a 20-gauge stainless steel needle directed at an angle of ~45? to prevent contact between any draining fluid and the HV needle and to provide clearance for the capillary root support. The flow of nutrients will be controlled by a programmable syringe pump. Humidity and temperature in the plant chamber will be set to typical greenhouse levels of 80% and 22 ?C in an environmental chamber.Nutrient delivery measurement for plant studies: For the plant growth trials, each reported trial will consist of an individual plant that will be harvested at the end of the trial period. All water use efficiency measurements will be repeated in triplicate, and selected plants will be sent for nutrient analysis. The consumption of water will also be assessed. The results will be compared to those obtained from the control treatments that are listed below.Control groups for plant studies: Two types of control treatments will be utilized: a) uncoated seeds of the two varietals will be added to growth media and treated with ESD and b) uncoated seeds grown with traditional hydroponics approaches.Development of a scale up Electroponics prototype for field testing (AIM 2)In this aim based on the data of the single module lab based electroponics system (AIM-1), we will develop a scaleup fully automated electroponics system suitable for plant growth studies (AIM-3). What will also need to be determined is the number of plants that can: (1) effectively be monitored with a single nanoammeter and saturation monitor and (2) effectively be stabilized with a single electrospray power supply.Upscaling of nutrient supply flow: To enable the number of fluid channels required for the upscaled prototype, we will shift our fluid supply at this stage from a syringe pump unit to a larger software controlled nutrient supply peristaltic pumpAIM 3: Field testing assessment of efficacy of the Electroponics prototype for germination and crop developmentThe Electroponics scaleup prototype developed in Aim 2 will be utilized for greenhouse studies using two model plants. namely Bibb Lettuce and dwarf tomato.Control plant groups: Two types of control plant groups will be utilized for each plant cohort: a) A panel of 16 hydroponically grown plants with nanofiber coated seeds and b) 16 hydroponically grown plants with commercially available non-nanofiber coated seeds.Water and nutrient use: For the duration of the plant growth, we will monitor and measure the use of water and nutrients for the electroponically grown plants and the control groups using the conventional hydroponic approach.Physiological, biochemical and molecular endpoints for the plants: For the plants grown in greenhouse conditions, various endpoints relevant to healthy plant growth will be assessed using state of the art analytical methods.