Identification of plant leaf phosphorus content at different growth stages based on hyperspectral reflectance

Abstract

Background: Modern agriculture strives to sustainably manage fertilizer for both economic and environmental reasons. The monitoring of any nutritional (phosphorus, nitrogen, potassium) deficiency in growing plants is a challenge for precision farming technology. A study was carried out on three species of popular crops, celery (Apium graveolens L., cv. Neon), sugar beet (Beta vulgaris L., cv. Tapir) and strawberry (Fragaria × ananassa Duchesne, cv. Honeoye), fertilized with four different doses of phosphorus (P) to deliver data for non-invasive detection of P content. Results: Data obtained via biochemical analysis of the chlorophyll and carotenoid contents in plant material showed that the strongest effect of P availability for plants was in the diverse total chlorophyll content in sugar beet and celery compared to that in strawberry, in which P affects a variety of carotenoid contents in leaves. The measurements performed using hyperspectral imaging, obtained in several different stages of plant development, were applied in a supervised classification experiment. A machine learning algorithm (Backpropagation Neural Network, Random Forest, Naive Bayes and Support Vector Machine) was developed to classify plants from four variants of P fertilization. The lowest prediction accuracy was obtained for the earliest measured stage of plant development. Statistical analyses showed correlations between leaf biochemical constituents, phosphorus fertilization and the mass of the leaf/roots of the plants. Conclusions: Obtained results demonstrate that hyperspectral imaging combined with artificial intelligence methods has potential for non-invasive detection of non-homogenous phosphorus fertilization on crop levels.

Influence of nitrogen source and rate on lettuce yield and quality

“…The highest LMD and CLS were recorded with no fertilizer application (Figure 4b,c). This result could be expected as N application results in higher chlorophyll content in leaf tissue (Bruce et al., 2018; Siedliska et al., 2021; Ziadi et al., 2008). As N fertilization increased more accumulation of N was recorded in the leaf tissue regardless of source of fertilizer application.…”

“…Moreover, cultivars of lettuce can be different in their susceptibility to physiological disorders. Lower application of N, regardless of N source, can reduce the chlorophyll content of the lettuce leaf tissue (Bruce et al., 2018; Siedliska et al., 2021; Ziadi et al., 2008) resulting in yellow‐white or pale leaves and therefore increasing the incidence of chlorosis (CLS) and leaf marginal discoloration (LMD) negatively affecting lettuce marketability. In contrast, excess N fertilization can increase the incidence of tipburn (TB) that could be related to the increase in head size, Ca deficiency, or specific N effect by decreasing root/shoot ratio (Kirkby, 1979; Olle & Bender, 2009).…”

Application of Hyperspectral Technology Combined With Bat Algorithm-AdaBoost Model in Field Soil Nutrient Prediction

“…Moreover, JCV Puno et al used genetic algorithms for the qualitative level classification of soil nutrients [36]. A large number of scholars have also installed sensor devices in fields to measure soil moisture, electrical conductivity, and pH to invert soil nutrient content [37,38].…”

Composition, activity and diversity of bacterial and fungal communities responses to inputs of phosphorus fertilizer enriched with beneficial microbes in degraded Brunic Arenosol

“…P is involved in enzymatic and metabolic processes (such as photosynthesis and cell division), formation of phospholipids and constitute the vital element of nucleic acids. Unfortunately, the majority of soil P (~95%) is unavailable for plant uptake and, in addition, prolonged or inappropriate application of phosphorus mineral fertilizers may result in limitation of indigenous P (Hallama et al, 2021; Siedliska et al, 2021). With regard to the disadvantages of mineral fertilizers, the use of beneficial microorganisms capable of converting insoluble P‐compounds into ortho‐phosphates which can be uptaken by plants, seems to be an innovative and ecofriendly alternative or supplementation (Hallama et al, 2021; Kour et al, 2020).…”