Greenhouse Assays with Lactuca sativa for Testing Sewage Sludge-Based Soil Amendments

Sustainable agriculture practices within the guidelines of nutrient recycling and the circular economy must be increasingly promoted. This work aims to evaluate the performance of dried sewage sludge (DSS), green liquor dregs mixed with sewage sludge (DSSA), raw sewage sludge, and commercial organic fertilizer control, using a short-term agronomic assessment with lettuce crop (Lactuca sativa) in greenhouse conditions. Different application rates based on the nitrogen content were tested for each soil amendment: 0, 85, 170, and 225 kg N/ha (treatments T0, T1, T2, and T3, respectively). DSS and DSSA resulted in fresh lettuce productivities 1.3 and 3.2 times higher in T3 than in T0, respectively. The ideal N content in lettuce leaves was reached for all materials and treatments, with the highest values obtained for DSS (2.88–3.33% from T1 to T3). Lettuce produced in soils amended with DSS and DSSA showed also ideal levels of Ca. Overall, the performance of sludge-based products was similar to commercial fertilizer, without impairing the nutritional balance of the crop and the soil.

Chemical control and herbicide resistance of hairy fleabane [Conyza bonariensis (L.) Cronquist] in Jordan

Two field experiments were conducted to evaluate the effectiveness of 12 herbicides in controlling hairy fleabane [ Conyza bonariensis (L.) Cronquist] in a date palm orchard located in the central Jordan valley during the spring of 2017. Results showed that C. bonariensis resists paraquat (2.5, 5 and 7.5kgha -1 ), oxadiazon (5kgha -1 ) and oxyflourfen (3.3kgha -1 ) herbicides applied at normal or higher than the recommended rates. None of the three herbicides was significantly effective against the weed and treated plants continued growing normally similar to those of untreated control. Higher rates (10-fold of the recommended rates) of the same herbicides failed to control the weed. The effect of other tested herbicides on the weed was varied with bromoxynil plus MCPA (buctril ® M), 2,4-D- iso-octyl ester, glyphosate, glyphosate trimesium and triclopyr were most effective and completely controlled the weed at recommended rates of application. Testing paraquat, oxadiazon and oxyflourfen using the normal recommended and 10-fold higher rates on two populations of C. bonariensis grown from seeds of the date palm and al-Twal (another site in the Jordan Valley) weed populations and grown in pots under glasshouse conditions showed that Date palm population was resistant to the three herbicides at both application rates while al-Twal site population was highly susceptible and completely controlled at normal and high rates of the three herbicides. It is concluded that certain populations of C . bonariensis developed resistance to paraquat, oxadiazon and oxyflourfen but control of this weed was possible using other herbicides of different mechanism of action. Herbicide rotation or other nonchemical weed control methods have been suggested to prevent or reduce the buildup and spread of resistant populations of this weed species. These results represent the first report on herbicide resistance of C. bonariensis in Jordan.

Development of Artificial Intelligence Climate Chamber and Experimental Study on Crop Phenotype Acquisition

Background: The deficiencies of traditional artificial climate chambers in phenotypic collection and analysis were improved to achieve the high-throughput acquisition of crop phenotypes during the growth period. This paper has developed an artificial intelligence climate cabin with functions of crop cultivation management and phenotype acquisition during the whole growth period. This research also established an environmental control system, a crop phenotype monitoring system and a crop phenotype acquisition system with environmental parameter adjustment and crop image collection. Phenotypic feature extraction and other functions were carried out in the cultivation experiment, and phenotype acquisition of wheat was performed under different nitrogen fertiliser application rates. Comparison and analyses were performed by the systematic and manual measurement values of crop phenotype characteristics, and the acquisition of wheat table was evaluated based on artificial intelligence climate cabin. The goodness of fit of the model was used to classify data.Results: During the different growth periods of wheat, the correlation analysis between the systematic and manual measurement values of its leaf area, plant height and canopy temperature showed that the obtained correlation coefficient r was greater than 1, and the fitting determination coefficient R2 was greater than 0.7156, with errors. The coefficient root mean square error was less than 2.42, indicating that the two were positively correlated, and their correlation was excellent. Conclusion: The results verified the feasibility and applicability of the artificial intelligence climate cabin to study the phenotypic characteristics of crops.

TWO-COMPONENT HERBICIDE HORS D, KS FOR THE PROTECTION OF CORN CROPS

The research was carried out to assess the biological and economic effectiveness of the new two-component herbicide Hors D, KS (220 g/l dicamba (sodium salt) and 50 g/l nicosulfuron) of LLC “Agro Expert Group” on corn crops in Krasnodar Krai. The experiments were carried out in the field conditions of All-Russian Research Institute of Biological Plant Protection in 2018-2019 according to the methodological guidelines for registration tests of herbicides in agriculture. The soil is leached chernozem. The area of the plots is 25 m2, the repetition rate is 4 times, the flow rate of the working fluid is 200 l/ha. The experimental scheme included the use of the tested herbicide Hors D, KS in the application rates of 0.6; 0.8 and 1.2 l/ha. Carleone preparation was used as a standard, EC (0.3 and 0.6 l/ha) and control (without herbicides). The treatment was carried out in the phase of 3...5 leaves of the culture. The contamination of corn crops averaged 83 copies/m2. The herbicidal effect of the drugs was assessed by reducing the number and weight of weeds, as well as by the crop yield in comparison with the control. Weeds: common hedgehog, glaucous bristle, ragweed wormwood, tilted backward and Californian cocklebur showed a high sensitivity to drugs. The use of 0.6...1.2 l/ha of Hors D, KS led to an 80 ... 100% herbicidal effect. There was no negative effect of the drug for corn plants, crop yield increases were obtained, which amounted to 62.0...74.7% of the control. The obtained data for two years showed high biological and economic efficiency of the herbicide Hors D, KS against annual dicotyledonous and cereal weeds in corn crops

Responses of Garlic Quality and Yields to Various Types and Rates of Potassium Fertilizer Applications

Potassium (K) is a critical plant nutrient that determines quality in a myriad of crops and increases production yields. However, excessive application of various types of K fertilizers can decrease both the food quality and yields, which translates as economic losses and food safety issues. The objectives of this study were to 1) elucidate the impacts of different application rates of various K fertilizers on garlic, with the aim to identify the optimal and most economical K fertilizer dosage and 2) compare the effects of applying two common K fertilizers (KCl and K2SO4) on garlic, to determine the optimal combination. From 2018 to 2020, we utilized two distinct K-fertilized fields to conduct our experiments. The results revealed optimal KCl fertilization increased the biomass and vegetation index in garlic, and promoted the transfer of nitrogen, phosphorus, and potassium nutrients from the stem and leaf to bulb, thereby increasing bulb production. The application of KCl fertilizer increased the number of cloves, the diameters of the cloves and bulbs, and reduced variations in bulb size. In addition, the application of KCl fertilizer improved the nutritional quality (Vitamin C, soluble sugar, soluble protein, and allicin) of the garlic and reduced the accumulation of nitrate. However, excessive KCl fertilizer cause decreased yields, appearance traits, and nutritional quality. Applying the same rate of K fertilizer in the form of K2SO4 in isolation increased the garlic yield by only 0.1% to 22.5% when compared with KCl fertilizer. However, the results were not always significant. In this study, the highest yields, appearance traits, and nutritional quality were achieved with the ratio of K2SO4: KCl = 3:1. Consequently, to ensure the highest economic value (considering the market prices of K fertilizer, garlic sprouts, and bulbs), the authors recommend a K fertilizer rate of 252.5 kg·ha−1 K2O, with K2SO4 accounting for 61.6% for garlic production in field.

Can Biofertilizers Reduce Synthetic Fertilizer Application Rates in Cereal Production in Mexico?

Biofertilizers are considered as potential supplements or alternatives to fertilizers. The objective of the present study is to evaluate different biofertilizers in combination with synthetic fertilizers on the yields of maize and wheat in several states in Mexico. Fourteen biofertilizer treatments plus a treatment with 100% the locally recommended fertilizer rate (RFR), another with 50% RFR (the control treatment), and one without any fertilizer (for a total of 17 treatments) were tested on maize and wheat in five states across Mexico. Field experiments were established in five states and several years for a total of 14 experiments in Mexico. In general, except for the experiments conducted in moderately low soil P conditions, Chiapas and Sonora (maize), no response to biofertilizers was observed in the remaining locations, through the years in wheat and maize. We conclude that in high input production systems, the biofertilizer response is more an exception than a rule with only 21% of the experiments showing a significant difference in favor of biofertilizers and only 4 of 15 products tested produced a yield response in more nitrogen deficient environments. Some products containing AMF may be beneficial in maize production systems with phosphorus deficient environments.

Assessment of Reactive Nitrogen Flows in Bangladesh’s Agriculture Sector

To assess the status of and trends in agricultural nitrogen (N) flows and their wider consequences for Bangladesh, in this study, we analyzed data from national and international bodies. The increased rates of N fertilizer applied for increased food production leaves behind a huge amount of unutilized reactive N (Nr). N fertilizer use is the largest in the crop sector, an important sector, where current annual consumption is 1190 Gg. The present combined annual Nr production from crop, fishery, and livestock sectors is ~600 Gg, while emissions of nitrous oxide (N2O), a potent greenhouse gas, are ~200 Gg. Poor N management results in Nr leaking into the environment, which has increased approximately 16-fold since 1961. One potential consequence is the disruption of ecosystem functioning. The balanced tradeoff between food production and reducing Nr input needs to be achieved. One solution to reducing Nr may be a holistic approach that optimizes N application rates and incorporates waste of one subsector as an input to another applying the principle of the circular economy.

Rapid Detection of Urea Fertilizer Effects on VOC Emissions from Cucumber Fruits Using a MOS E-Nose Sensor Array

The widespread use of nitrogen chemical fertilizers in modern agricultural practices has raised concerns over hazardous accumulations of nitrogen-based compounds in crop foods and in agricultural soils due to nitrogen overfertilization. Many vegetables accumulate and retain large amounts of nitrites and nitrates due to repeated nitrogen applications or excess use of nitrogen fertilizers. Consequently, the consumption of high-nitrate crop foods may cause health risks to humans. The effects of varying urea–nitrogen fertilizer application rates on VOC emissions from cucumber fruits were investigated using an experimental MOS electronic-nose (e-nose) device based on differences in sensor-array responses to volatile emissions from fruits, recorded following different urea fertilizer treatments. Urea fertilizer was applied to cucumber plants at treatment rates equivalent to 0, 100, 200, 300, and 400 kg/ha. Cucumber fruits were then harvested twice, 4 and 5 months after seed planting, and evaluated for VOC emissions using an e-nose technology to assess differences in smellprint signatures associated with different urea application rates. The electrical signals from the e-nose sensor array data outputs were subjected to four aroma classification methods, including: linear and quadratic discriminant analysis (LDA-QDA), support vector machines (SVM), and artificial neural networks (ANN). The results suggest that combining the MOS e-nose technology with QDA is a promising method for rapidly monitoring urea fertilizer application rates applied to cucumber plants based on changes in VOC emissions from cucumber fruits. This new monitoring tool could be useful in adjusting future urea fertilizer application rates to help prevent nitrogen overfertilization.