Effect of Mycorrhiza and Vermicompost on Drought Tolerance of Lime Seedlings ( Citrus aurantifolia Cv. Mexican Lime)

Abstract

In order to investigate the effect of mycorrhizal arbuscular fungi (MAF) and vermicompost on drought tolerance of Mexican Lime seedlings (Citrus aurantifolia cv. Mexican Lime), a factorial experiment was conducted as a completely randomized design in greenhouse conditions. Factors included were water stress at three levels (100% ET c , 70% ET c and 40% ET c ) and biofertilizers at three levels (0, 100 g mycorrhiza, 100 g vermicompost per pot) with four replications. Irrigation treatments were applied for two months on one year seedlings. The results showed that growth of leaf and root was significantly affected by drought stress and decreased, whereas the effect of drought stress on fresh and dry weight of stem was not statistically significant. According to the results, the rate of decrease in fresh and dry weight of leaves under severe water stress treatment compared to full irrigation was 35.38 and 31.79%, respectively. Also, the rate of decrease in fresh and dry weight of root in severe water stress treatments was 35.53 and 34.11%, respectively, compared to full irrigation. Inoculation of seedlings with bio-fertilizers especially 100 g mycorrhiza per pot significantly increased leaf fresh weight (19.94%), leaf dry weight (17.31%), stem fresh weight (26.7%), stem dry weight (26. 1%), root fresh weight (35.53%), root dry weight (14.82%), RWC (76.19%), enzyme activity, chlorophyll a -(0.637 mg.g f.w.), b (0.372 mg.g f.w.) and carotenoid (11 mg.g f.w.) and reduced ion leakage (62.5%) compared to non-inoculated seedlings. Based on the results, it can be stated that application of 100 g bio-fertilizer could reduce adverse effects of drought stress on the Mexican Lime seedlings.

Unravelling the role of arbuscular mycorrhizal fungi in mitigating the oxidative burst of plants under drought stress

“…Total content of phenols was increased by Glomus versiforme in maize under two drought regimes, indicating that AMF-induced phenols, as active scavengers of ROS, protect cellular structures and the functioning of their hosts (Begum et al 2019). Numerous studies have confirmed that AMF inoculation enhances concentrations of carotenoids in Aloe barbadensis, Citrus aurantifolia, Ricinus communis and Zinnia elegans under drought stress (Zhang et al 2018b;Bagheri et al 2019;Khajeeyan et al 2019;Nejad et al 2019). An increase in carotenoids in droughtstressed host plants by AMF inoculation could quench more 1 O 2 from excess light energy, thereby protecting the photosynthetic machinery from photo-oxidative damage (Shi et al 2015).…”

“…Symbiotic associations are characterized by the stimulation of host nutrient uptake by AMF in return for photosynthetic products and lipids form the plants for AM fungal growth. AMF act as protection for host plants against drought stress via a series of underlying mechanisms, including (i) direct water absorption of the mycorrhizal extraradical mycelium; (ii) physiological improvements in nutrient acquisition, osmotic adjustment, hormone balance, antioxidant protective systems, fatty acids (FAs) and polyamines (PAs); (iii) host morphological adaptation; (iv) soil structure improvement by the mycorrhizal extraradical mycelium; and (v) molecular changes (Blee & Anderson, 2000;Ruiz-Lozano et al 2012;Wu et al 2013Wu et al , 2019Millar & Bennett 2016;Nath et al 2016;Liu et al 2018;Zhang et al 2020).…”

“…Plants are continuously exposed to the external environment, including abiotic and biotic stresses (Nath et al 2016). Abiotic stress produces adverse effects on crop growth and production (Millar & Bennett 2016).…”

Arbuscular mycorrhizal fungi, phosphate-solubilizing bacteria, and zinc foliar application improve physiological responses in black cumin (Nigella sativa) under drought stress

“…As a result, and in accordance with the concept of sustainable agriculture, there is a growing interest in using soil microorganisms to increase crop production and reduce damage from biotic and abiotic stresses. To this end, utilizing biofertilizers such as arbuscular mycorrhizal fungi (AMF) is an effective short-term strategy for mitigating the detrimental effects of various stress conditions (Zeighami Nejad et al 2019).…”

Future of Irrigation in Agriculture in Southern Europe

“…Even though higher [CO 2 ] levels could be considered a positive factor in relation to improvements in WUE i , there is little information regarding the physiological interactions promoted by the increase in [CO 2 ] and air temperature and water stress situations. According to this, if water stress conditions extend over time and coincide with high radiation rates, oxidative stress can be promoted, generating reactive oxygen species (ROS) [18]. The increase in ROS can be accompanied by a synthesis of enzymes with antioxidant activity (catalase, dismutase superoxide, or peroxidase, among others), and if the water stress is very severe, it may promote lipidic peroxidation [19].…”