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The purpose of this study was to develop an independent multi-criteria model to predict the growth of invasive Alternanthera philoxeroides under salt stress. Artificial neural-networks with Multi-Layer Perceptron (MLP) were used for building a Predicted Neural Model (PNM) using soil parameters such as pH, electrical conductivity (EC), water content, temperature, humidity, and organic content and a growth parameter, i.e. plant height. Quality assessment of the produced PNM is done through ex-post errors, i.e. Relative-Approximation Error (RAE), Root-Mean Square (RMS) error, Mean-Absolute Error (MAE), and Mean-Absolute Percentage Error (MAPE). The MAPE was 2.21% for PNM of A. philoxeroides, which was less than 10%, thus proving that all the obtained results are highly satisfactory. In the next step, the sensitivity analysis assigned the highest rank 1 to salt stress in the model with a quotient value of 1.71, and the rank-2 was assigned to EC of soil with quotient value of 1.51. Therefore, the constructed PNM will provide the basis for building new prediction tools for the growth of invasive species. It will be an important element for prediction of invasiveness of A. philoxeroides in a stressful environment and will also be helpful for the management of invasive species. [ABSTRACT FROM AUTHOR]

Nitrobenzene (NB) is toxic and carcinogenic aromatic compound widely used in several industries which is ultimately found in their effluents. In this work, dielectric barrier discharge (DBD) reactor was employed for the degradation of nitrobenzene in aqueous solution. Active species like O3 and •OH produced by DBD reactor were mixed with water which degraded the NB. The results indicated that the lower NB concentrations slightly acidic conditions and high voltage ranges showed the optimum efficiencies. Moreover, the impacts of active species inhibitors isopropyl alcohol (IPA), tert-butanol (TBA), inorganic ions for instance sulfates ( S O 4 2 − ), bicarbonates ( H C O 3 − ), nitrates ( N O 3 − ), carbonates ( C O 3 2 − ) and chlorides (Cl−) on the degradation of NB were examined. This analysis showed that the hydroxyl radical was captured by the addition of these inhibitors and resulted in the decrease in efficiencies. Byproducts produced during the degradation of nitrobenzene were assessed by analytical techniques of high-performance liquid chromatography (HPLC), liquid chromatography–mass spectrometry (LC–MS), UV–visible spectroscopy and total organic carbon (TOC) analysis. Main intermediate products were nitrophenols and low molecular weight organic acids including oxalic acid and acetic acid that were eventually mineralized to CO2 and H2O. The dielectric barrier discharge technology was found productive for the degradation of nitroaromatic compounds. [ABSTRACT FROM AUTHOR]

In the present study, the effect of buried straw (two levels; MS; buried straw layer and MN; no straw layer), nitrogen fertilizer (two levels: FH, 120 kg ha−1 and FL, 80 kg ha−1), and deficit drip irrigation with irrigation frequency of 2 days (two irrigation regimes: I50; 50% and I30; 30% of evapotranspiration) was investigated on a greenhouse-grown leafy cabbage for two consecutive seasons. The results indicated that in both the seasons, T5 (MNFHI50) gave higher yield when compared to all other treatments but it also utilized more water and fertilizer. On the other hand, with a 5–10% decrease in yield comparing to T5 (MNFHI50), T2 (MBSFLI50) and T4 (MSFLI30) saved 33% of fertilizer. T4 (MBSFLI30) also gave the highest water and fertilizer use efficiencies when compared to all other treatments. However, it was clearly noted that T4 (MSFLI30) treatment could save water and nitrogen without a significant decrease in fresh yield of Chinese cabbage. Hence, T4 (MsFLI30) is the recommended strategy to manage water and nitrogen fertilizer for getting optimal leafy cabbage plant growth and yield. [ABSTRACT FROM AUTHOR]

To evaluate the effects of different irrigation and nutrient concentration strategy on growth, yield, water use efficiency (WUE), fruit quality and substrate salt accumulation, tomatoes were grown with five different levels of water (W: 50%, 75%, 100%, 125% and 150%) and nutrient concentrations (N: 0.5, 0.75, 1.0, 1.5 and 2.0 times of Hoagland strength(X)). Fruit quality index was determined by normalization of fruit quality parameters. Deficit irrigation at standard concentration of nutrients reduced yields by 17.43% and 15.52% for T7(W75%-N1.0x) and 49.54%–51.99% for T8(W50%-N1.0x) during spring-summer (SS) and fall-winter (FW) seasons, respectively. Contents of total soluble solids (TSS), titrable acidity (TA) and sugar acid ratio (SAR) were all increased in water-deficit treatments. T8was found to be highest in TSS, TA and SAR except SAR in FW. Over-irrigation with excessive and standard Hoagland nutrient concentration caused non-significant reduction in yield except T6(W125%-N1.0x) in SS. T2(W100%-N2.0x) and T4(W100%-N1.5x) caused more substrate salt accumulation which resulted in significant decrease in yield and WUE. Through economic analysis, over-watering along with excessive nutrients caused profit reductions. Considering water saving, yield and fruit quality through economic analysis, T7found to be optimal strategy. [ABSTRACT FROM PUBLISHER]

Effect of salt stress and subsequent re-watering on growth and electrophysiological characteristics ofOrychophragmus violaceusandBrassica napuswas investigated, to construct a model for prediction of an appropriate regime for dilution of saline water. Different concentrations of NaCl, Na2SO4and blend of both salts were applied with Hoagland solution. Growth and electrophysiology traits were highly restricted at high concentration levels. According to the results, the best dilution point was 5–2.5% for NaCl and Na2SO4alternatively, whereas it was 10–0.0% for blend of salts. After re-watering,O. violaceusrestore better leaf tensity under medium levels, because the effect of NaCl concentration on leaf tensity (XNC–LT) was 1.66%, which was lower inO. violaceusthan the effect ofXNC–LT(2.88%) inB. napus,followed by the same trend for all treatments. Therefore, the effect of salinity inO. violaceusandB. napusmay also be reduced effectively by dilution of saline irrigation. [ABSTRACT FROM PUBLISHER]

This research was conducted to determine the water consumption of tomato plants, the effects of water stress on stem sap flow (SF) and its response to climatic factors. SFs in 100% irrigation (T1), 75% (T2) and 50% (T3) of irrigation amount of T1were monitored using Dynagage sensors. Compared to T1, the difference in SF was observed under deficit irrigation in the same climatic conditions on sunny days although there was no apparent difference between T1and T2on cloudy days. Under T1, the correlation and regression relationships between SF and climatic factors were analyzed at daytime (6:00–22:00), morning (6:00–14:00) and afternoon (14:00–22:00). Considering daytime, the order of sensitive indicators to SF was VPD > LI > Ta and LI > VPD > Ta for the Fall-Winter sunny days and Spring-Summer season, respectively. The water uptake over SFs measured for Fall-Winter and Spring-Summer periods were calculated as 168.65 and 229.18 mm, respectively. [ABSTRACT FROM PUBLISHER]

Two cultivars of okra (Chinese green and Chinese red) were subjected to salt stress (0%, 6%, 12% and 18%) and equal proportions of NaCl and CaCl2in Hoagland’s nutrient solution and re-watering. Salt stress significantly reduced growth parameters and photosynthetic attributes of both cultivars. Treatment subjected to 18% salt stress caused 90% redundancy in growth parameters of both cultivars compared to control. Re-watering gave a positive response for plant growth of both cultivars in different levels. Chinese green showed better recovery at 6–0% re-watering level and Chinese red showed 12–6% and 6–0%, due to its salt tolerance nature. Considering re-watering water use efficiency and net photosynthetic rate the optimum values of salt tolerance for Chinese green and Chinese red were 8.3% and 12.02%, respectively. The best re-watering degree found as salt stress level ranged from 12.02% to 6% for Chinese red and 8.3% to 2.3% for Chinese green. This study provided a new method for the determination of irrigation time and quantification in crops. [ABSTRACT FROM PUBLISHER]