A novel NIR-image segmentation method for the precise estimation of above-ground biomass in rice crops.

Traditional methods to measure spatio-temporal variations in biomass rely on a labor-intensive destructive sampling of the crop. In this paper, we present a high-throughput phenotyping approach for the estimation of Above-Ground Biomass Dynamics (AGBD) using an unmanned aerial system. Multispectral imagery was acquired and processed by using the proposed segmentation method called GFKuts, that optimally labels the plot canopy based on a Gaussian mixture model, a Montecarlo based K-means, and a guided image filtering. Accurate plot segmentation results enabled the extraction of several canopy features associated with biomass yield. Machine learning algorithms were trained to estimate the AGBD according to the growth stages of the crop and the physiological response of two rice genotypes under lowland and upland production systems. Results report AGBD estimation correlations with an average of r = 0.95 and R2 = 0.91 according to the experimental data. We compared our segmentation method against a traditional technique based on clustering. A comprehensive improvement of 13% in the biomass correlation was obtained thanks to the segmentation method proposed herein.

In Vitro Assay of Quinoa (Chenopodium quinoa Willd.) and Lupin (Lupinus spp.) Extracts on Human Platelet Aggregation.

Cardiovascular disease (CVD) is the leading cause of death throughout the world. A major risk factor for CVD is platelet aggregation. Various plant extracts exhibit anti-aggregatory action in vitro. The dietary intake of traditional plant crops such as quinoa (Chenopodium quinoa Willd) and lupin (Lupinus spp., Fabaceae family), highly recognized for their high nutritional value, is increasing worldwide. The aim of the study was to assay possible antiplatelet effects of quinoa and lupin bean extracts in vitro. The proximate chemical composition of quinoa grains and the three most widely known lupin cultivars: blue (L. angustifolius), yellow (L. luteus or mutabilis) and white (L. albus) grown in Chile were analyzed. The anti-aggregation activity of the ethanol extracts of the crops was assayed using flow cytometry in ADP-stimulated human platelets, and their inhibition of the maximal platelet aggregation was measured. All the lupin extracts exhibited a significant anti-aggregatory effect (p < 0.0001), while quinoa extracts did not exert this effect compared to control platelets. In conclusion, lupin beans extracts exhibited an anti-aggregatory effect on activated human platelets.