Machine Learning Approach to Predict Quality Parameters for Bacterial Consortium-Treated Hospital Wastewater and Phytotoxicity Assessment on Radish, Cauliflower, Hot Pepper, Rice and Wheat Crops

Raw hospital wastewater is a source of excessive heavy metals and pharmaceutical pollutants. In water-stressed countries such as Pakistan, the practice of unsafe reuse by local farmers for crop irrigation is of major concern. In our previous work, we developed a low-cost bacterial consortium wastewater treatment method. Here, in a two-part study, we first aimed to find what physico-chemical parameters were the most important for differentiating consortium-treated and untreated wastewater for its safe reuse. This was achieved using a Kruskal–Wallis test on a suite of physico-chemical measurements to find those parameters which were differentially abundant between consortium-treated and untreated wastewater. The differentially abundant parameters were then input to a Random Forest classifier. The classifier showed that ‘turbidity’ was the most influential parameter for predicting biotreatment. In the second part of our study, we wanted to know if the consortium-treated wastewater was safe for crop irrigation. We therefore carried out a plant growth experiment using a range of popular crop plants in Pakistan (Radish, Cauliflower, Hot pepper, Rice and Wheat), which were grown using irrigation from consortium-treated and untreated hospital wastewater at a range of dilutions (turbidity levels) and performed a phytotoxicity assessment. Our results showed an increasing trend in germination indices and a decreasing one in phytotoxicity indices in plants after irrigation with consortium-treated hospital wastewater (at each dilution/turbidity measure). The comparative study of growth between plants showed the following trend: Cauliflower > Radish > Wheat > Rice > Hot pepper. Cauliflower was the most adaptive plant (PI: −0.28, −0.13, −0.16, −0.06) for the treated hospital wastewater, while hot pepper was susceptible for reuse; hence, we conclude that bacterial consortium-treated hospital wastewater is safe for reuse for the irrigation of cauliflower, radish, wheat and rice. We further conclude that turbidity is the most influential parameter for predicting bio-treatment efficiency prior to water reuse. This method, therefore, could represent a low-cost, low-tech and safe means for farmers to grow crops in water stressed areas.

Image-Based Hot Pepper Disease and Pest Diagnosis Using Transfer Learning and Fine-Tuning

Past studies of plant disease and pest recognition used classification methods that presented a singular recognition result to the user. Unfortunately, incorrect recognition results may be output, which may lead to further crop damage. To address this issue, there is a need for a system that suggest several candidate results and allow the user to make the final decision. In this study, we propose a method for diagnosing plant diseases and identifying pests using deep features based on transfer learning. To extract deep features, we employ pre-trained VGG and ResNet 50 architectures based on the ImageNet dataset, and output disease and pest images similar to a query image via a k-nearest-neighbor algorithm. In this study, we use a total of 23,868 images of 19 types of hot-pepper diseases and pests, for which, the proposed model achieves accuracies of 96.02 and 99.61%, respectively. We also measure the effects of fine-tuning and distance metrics. The results show that the use of fine-tuning-based deep features increases accuracy by approximately 0.7–7.38%, and the Bray–Curtis distance achieves an accuracy of approximately 0.65–1.51% higher than the Euclidean distance.

Growth, Fruit Yield and Proximate Composition Responses of Hot Pepper (Capsicum annuum L; Rodo Variety) to Potassium Fertilizer Application at Ado-Ekiti, Nigeria

Potassium (K) fertilizer application, as a component of the improved technologies necessary to maximize crop yield and quality, is often used to correct the plant, soil and environmental factors that limit K availability. The effects of 0, 30, 60 and 90 kg K2O ha-1 were studied on hot pepper (Capsicum annuum L; Atarodovariety) in 2014 and 2015 on the Teaching and Research Farm, Ekiti State University, Ado-Ekiti Nigeria in a Randomized Complete Block Design with four replicates. Each K rate was mixed with 75 kg N and 25 kg P2O5 ha-1 and applied 2 weeks after transplanting 5-week old seedlings spaced 60 cm × 40 cm apart. The data of growth parameters were collected at 2 weeks after treatment (WAT) and fortnightly till 10 WAT, number and weight of ripe fruits and fruit proximate composition. The plant height, number of leaves, leaf area and dry matter increased with age and K rates to highest values at 10 WAT and 90 kg K2O ha-1 in both years. The number of fruits, fruit and seed yield ha-1, fruit size, fruit length and breadth and pericarp thickness increased linearly from the control to the highest values at 90 kg K2O ha-1.The number of fruits and yield at 90 kg K2O ha-1 were 1.253×106, 14.24 t ha-1; and 3.73×106, 14.94 t ha-1 in 2014 and 2015, respectively but the 60 kg K2O ha-1 gave the highest agronomic efficiency. The slight increase in fruit moisture content would not predispose fruits to deterioration while the crude protein and fat, carbohydrate and ash contents, vitamin C and mineral nutrients increased significantly making K application necessary to balance the fertilizer protocol for optimum hot pepper production.

Effect of Dose and Compound Fertilizer on Growth and Results of Red Chili

Effect of Dose and compound Fertilizer on the Growth and Yield of Hot Pepper plant (Capsicum annum, L.). This study aims to determine the effect of Formula Application and dosage of complete compound fertilizer on the growth and yield of chili plants. This study used a factorial Randomized Block Design (RAK) with nine treatment combinations and three replications, each treatment consisting of 3 plants. The combination of these treatments used two Complete Compound Fertilizer Formulas (P). Formula 1 (P1) Complete Compound Fertilizer Pril (PMLP), 2 (P2) : Complete Compound Fertilizer Tablets (PMLT), and 3 (P3) as a control mixture of single fertilizer Urea, SP 36, and KCL ( 1:1:1). The second formula is fertilizer dosage (D) which consists of three levels, namely D1 (30 g fertilizer/plant), D2 (40 g fertilizer/plant), and D3 (50 fertilizer/plant). The variables observed in this study were plant height, number of fruit per plant, fruit weight per plant, dry weight of plant stover. Based on the results of the research that has been carried out, it is concluded that the treatment of Complete Compound Fertilizer Formula (P) has a very significant effect on all observed variables, namely: plant height, number of fruits per plant, the weight of dry root, and weight of fruit per plant. While the Fertilizer Dosage (D): 30, 40, and 50 g did not show a significant difference in the results for all observed variables, and the interaction between the two did not show significant differences in all observed variables.

ATTITUDES OF SERBIAN CONSUMERS TOWARDS DIFFERENT PEPPER FRUITS

Pepper (Capsicum annuum L.) is one of the major vegetable species in the world. In Balkan cuisines, as well as in Serbia, pepper has a very diverse use. Knowledge about consumers habits and preferences is of great importance for a breeding process as well as in the market-orientated production. Because of the lack of information about consumers preferences towards pepper types, in the Serbian market, the present research was conducted. Four hundred and two participants, classified into groups, according to gender, age and education, answered the survey questions. According to this research, the most preferred pepper type in Serbia is kapia, while the bell pepper is the second chosen type. Also, obtained results showed that the most favourite colour of pepper fruit is red. There is a tendency in higher importance of fruit type than fruit colour. The highest percentage of hot pepper consumers prefer medium hot peppers. The obtained trend shows that women generally prefer less spicy pepper fruits than men.

Biostimulative effect of amino acids and green algae extract on capsaicinoid and other metabolite contents in fruits of Capsicum spp.

Background Biostimulants, such as algae extracts or amino acids, are becoming more common in agriculture because the mentality is to make plants more resistant or tolerant to negative environmental factors, rather than using synthetic chemicals (herbicides, insecticides and fungicides), whose use is decreasing year by year, forcing farmers and companies to develop new environmentally friendly products. Results In a field experiment, green algae and amino acids were tested as biostimulants on three hot pepper cultivars. A large variability was observed between the effects of the two biostimulants on the cultivars. Green algae-treated ‘Somborka’ and ‘Habanero Red Caribbean’ cultivars had 10% and 5% higher dry matter in seeds compared to control treatment. Total sugar content was negatively affected by green algae extract and amino acids in pericarp in cultivars ‘Chili AS-Red’ and ‘Habanero Red Caribbean’. Total organic acids content was positively affected by amino acid treatment in ‘Habanero Red Caribbean’ pericarp and placenta, with an increase of 5.5 g and 2.1 g/100 g DW, respectively. In terms of total phenolics, all three cultivars were positively affected by amino acid treatment, but not in each fruit part. In terms of capsaicinoid content, the greatest effect of the two stimulants was on ‘Somborka’, which varied from four (pericarp, seed) to 16 (placenta) times compared to the control. Amino acid extract decreased ‘Habanero Red Caribbean’ capsaicinoid content in placenta by about 40%. Conclusion Amino acids were found to be superior to algal extract, although the effect of both was mostly cultivar specific. For a wider use of biostimulants, it should first be tested whether they are suitable for the cultivar in order to increase and optimize the results. Graphic abstract