Increasing the okra salt threshold value with biochar amendments

Abstract

Soil salinity is a severe worldwide environmental problem that adversely affects soil properties and the crop growth such as okra. We hypothesized that biochar soil amendments could increase the okra salt threshold, alleviate salt stress and improve soil productivity. In this study, a pot experiment was conducted to investigate whether biochar could ameliorate the effects of salinity on okra plants. Three biochar amendment (BA) soil applications (0%, 5% and 10% by mass of soil) were considered for seven irrigation water salinity levels (0.75, 1.0, 2.0, 4.0, 5.0, 6.0 and 7.0 dS m −1) in a randomized block design with three replications. The Maas and Hoffman salt tolerance model was used to evaluate the effects of BA on okra plant growth parameters (e.g. yield, biomass) and water use efficiency for each salinity treatment. The results showed that increasing the soil salinity levels caused significant decreases in plant yields and yield components. However, biochar application rates of 5% and 10% increased the okra threshold by 19.7% and 81.2%, respectively, compared to the control (0%). The 10% biochar application rate also resulted in the greatest okra plant growth and increased yield, indicating that the effects of salt stress were ameliorated; moreover, the soil bulk density was decreased, and the water content was increased. Hence, biochar soil amendments could be considered as an important agronomic practice that could potentially overcome the adverse effects of salt stress.

Alpha Tocopherol-Induced Modulations in the Morphophysiological Attributes of Okra Under Saline Conditions

“…Okra is classified as a moderately sensitive crop to salinity stress by the Food and Agriculture Organization (FAO), and it is susceptible to salinity stress in areas where summers are dry ( Elshaikh et al, 2018 ). Based on germination, growth and yield characteristics, salinity tolerant (8 dSm –1 ) varieties of okra (OH-713, OH-139, OH-138, OH-2324 and OH-001) has been reported whereas the sensitive genotypes include Kiran, Okra-1548, Ikra-3, Sabzpari, Okra-7100, Sitara-9101, and Okra-7080 (sensitive 4 dSm –1 ).…”

Functional traits of okra cultivars (Chinese green and Chinese red) under salt stress

“…Other reports have removed salts from the root zone with the help of scraping, flushing and leaching (Jouyban, 2012). Some papers have evaluated the response of crops and vegetables to different concentrations of saline water and reported a higher production under slight and moderate concentrations of salts (Riccardi et al, 2014;Elshaikh et al, 2018). Furthermore, a number of researchers have reduced the effects of saline irrigation by applying the method of re-watering or by using diluted water after 1 week to a maximum of 3 weeks without considering the duration of the effects on plants (Azeem et al, 2017a(Azeem et al, , 2017bJaved et al, 2017Javed et al, , 2018.…”

Study on Okra (Abelmoschus esculentus L.) Response to Salt Stress Environment under Kabul Climatic Conditions, Afghanistan

“…Worldwide, over 800 million hectares of soil have been influenced by salts (Ifediora, Edeoga & Omosun, 2014). The existence of superfluous salt in water and soil is a serious environmental challenge (Ranga, Kumar, & Darvhankar, 2019) which negatively influenced the development of plants (Elshaikh, Zhipeng, Dongli & Timm, 2018, Kumar et al, 2017, Yakoubi, Babou, & Belkhodja, 2019 and reduces the quantity and quality of agricultural products (Abbas et al, 2013). Rocks weathering, irrigation of land with saline-water, poor management of irrigation, high evaporation rate, continuous and irregular application of chemical fertilizers are known as the key factors of soil salinization (Kumari et al, 2019).…”