Acta agriculturae Slovenica, 117/2 1–10, Ljubljana 2021 doi:10.14720/aas.2021.117.2.1510 Original research article / izvirni znanstveni članek Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters Zahra GHAHREMANI 1, * , Masoud NOROUZI 1 , Taher BARZEGAR 1 and Mohammad Ebrahim RANJBAR 1 Received February 27, 2020; accepted April 18, 2021. Delo je prispelo 27. februarja 2020, sprejeto 18. aprila 2021. Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters Abstract: Eggplant is one of the most popular and vital vegetable crops in the world. Various plant bio-regulators have been used in different crops to increase uptake of nutrients thereby leading to improvement in growth, flowering, fruit quality, storability and yield. The scope of this study was to evaluate the effects of calcium lactate and salicylic acid foliar application on growth parameters, physiological characteristics and shelf-life of eggplant fruit. Obtained results showed that the highest applied concentrations of calcium lactate (4 mM or 0.8 g l -1 ) and salicylic acid (1.5 mM or 0.2 g l -1 ) foliar application led to the highest values of measured growth parameters and yield. Applying of calcium lactate and salicylic acid foliar treat- ments could increase tissue firmness and ascorbic acid content of fruits. Foliar application of calcium lactate 4 mM (0.8 g l -1 ) and salicylic acid 1 mM (0.13 g l -1 ) was the best treatment to decrease percentage of fruit decay. In conclusion, our results showed that foliar application of calcium lactate and salicylic acid can be useful and inexpensive treatment to improve growth parameters, physiological characteristics and post-har- vest properties of eggplant fruit. Key words: eggplant; calcium sources; chlorophyll con- tent; foliar spraying; post-harvest fruit characteristics; salicylic acid. 1 Department of Horticulture, Faculty of Agriculture, University of Zanjan, Zanjan, Iran. I.R. * Corresponding author’s e-mail: z.ghahremani@znu.ac.ir Foliarno dodajanje kalcijevega laktata in salicilne kisline vpli- va na rast jajčevca in na obstojnost plodov pri shranjevanju Izvleček: Jajčevec je v svetovnem merilu ena izmed najbolj popularnih plodovk. Pri pridelavi različnih kulturnih rastlin so bili uporabljeni razni bioregulatorji privzema hranil, kar bi vo- dilo k izboljšanju rasti, cvetenja, kakovosti plodov, povečanju pridelka in trajnosti pri shranjevanju. Namen te raziskave je bil ovrednostiti učinke foliarnega dodajanja kalcijevega laktata in salicilne kisline na rastne parametre, fiziološke lastnosti in tra- janje plodov pri shranjevanju. Dobljeni izsledki so pokazali, da sta imeli največji foliarni dodajanji kalcijevega laktata (4 mM ali 0,8 g l -1 ) in salicilne kisline (1,5 mM ali 0,2 g l -1 ) največji učinek na vrednosti merjenih rastnih parametrov in velikosti pridel- ka. Foliarano obravnavanje s kalcijevim laktatom in salicilno kislino bi lahko povečalo čvrstost tkiv in vsebnost askorbinske kisline v plodovih. Foliarno dodajanje kalcijeva laktata 4 mM (0,8 g l -1 ) in salicilne kisline 1 mM (0,13 g l -1 ) je bilo najbolj- še obravnavanje za zmanjševanje odstotka propadlih plodov. Zaključimo lahko, da so ti izsledki pokazali, da bi lahko bilo foliarno dodajanje kalcijeva laktata in salicilne kisline uporaben in poceni postopek za izboljšanje rastnih parametrov, fiziološki lastnosti in lastnosti plodov jajčevca pri shranjevanju. Ključne besede: jajčevec; vir kalcija; vsebnost klorofila; foliarno gnojenje; lastnosti plodov pri shranjevanju; salicilna kislina Acta agriculturae Slovenica, 117/2 – 2021 2 Z. GHAHREMANI et al. 1 INTRODUCTION Eggplant (Solanum melongena L.) is one of the most popular and vital vegetable crops in the world (Kaushik, 2019). V arious plant bio-regulators have been used in dif- ferent crops to increase uptake of nutrients thereby lead- ing to improvement in growth, flowering, fruit quality, storability and yield (Ranjbar et al., 2017; Mustafavi et al., 2018; Ghahremani et al., 2020). However, recently new plant growth regulators like salicylic acid (SA) and calci- um lactate (CL) have been found beneficial in maintain- ing balance between vegetative and reproductive growth andincreasing the uptake of nutrients thereby resulting in high yield of superior quality crops with prolonged storability and consistent bearing (Shaarawi et al., 2016). Calcium (Ca 2+ ) has been extensively studied both as an essential element and for its potential role in maintaining postharvest quality of fruit and vegetable crops by con- tributing to the linkage between pectic substances within the cell wall. CL treatment reduced the respiration rate and improved the firmness of persimmon slices (Y oussef et al., 2017). SA is one of the groups of common phenolic compounds that are produced naturally by plants, which can act as endogenous plant growth regulator. Its appli- cation might be safe and more useful for plant growth improving. SA stimulates the growth and development of roots of the treated plants (by increasing of H + -ATPase activity and root ATP content) thereby improving nu- trient uptake (Ghassemi-Golezani and Farhangi-Abriz, 2018). Enhancement of chlorophyll and carotenoid pig- ments levels, photosynthetic rate and modifying the ac- tivity of some of the important enzymes are other roles assigned to SA. It induces specific changes in leaf anat- omy and chloroplast structure (Uzunova and Popova, 2000). The effect of postharvest calcium chloride (CC) and SA applications on shelf-life and quality attributes of kiwifruits were evaluated by Kazemi et al. (2011). Results of this experiment showed that post-harvest SA and CC treatments prevented fruit softening and decreased mass loss of fruits. Also in the other experiment, the effect of pre-harvest CC application on post-harvest life and qual- ity of peach fruits was studied. 0.5 %, 1.0 % and 1.5 % of CC solutions were sprayed on peach plants and CC 1.5 % resulted in maximum fruit firmness, sensory qual- ity score and calcium content during the storage period. The scope of the present research was to investigate the effects of CL and SA foliar application on growth pa- rameters, several fruit quality attributes such as tissue firmness, ascorbic acid content and total soluble solids of fruits and some of the most important post-harvest properties of eggplant fruit such as titratable acidity, fruit mass loss, fruit decay and browning of pulp tissue. 2 MATERIALS AND METHODS The experiment was conducted in University of Za- njan, Zanjan, Iran in 2018-2019. Soil samples of experi- mental farm were collected from a depth of 0 to 60 cm andthen analyzed. Table 1 shows the measured character- istics of experimental farm soil. Also, Table 2 shows qual- ity and chemical properties of applied irrigation water. 2.1 PLANT MATERIAL Eggplant seeds (IR3121 cultivar) were sawn in peat moss at controlled condition (23 ± 2 ° C temperature and 60 to 70 % relative humidity). Seedlings were transplant- ed to the field in 4-5 leaf stage (in May) at a distance of 60 cm between rows and 50 cm between plants. Seedlings were immediately irrigated after planting and then were watered by using of drip irrigation every 3 days. Weeds were controlled by hand weeding. Eggplant fruits were harvested at full ripening stage. Harvested fruits were stored at cold storage (10  ° C temperature and 85 ± 5 % relative humidity) for 30 days. Post-harvest characteris- tics evaluation was performed during storage at 10-day intervals. Table 1: Physical and chemical properties of experimental farm soil Clay (%) Silt (%) Sand (%) Soil texture Organic matter (%) K (g kg -1 ) 37 38 25 Clay loam 0.94 0.2 Na (g kg -1 ) Ca (g kg -1 ) N (%) EC (dS m -1 ) pH 0.13 0.12 0.07 1.49 7.4 Table 2: Quality and chemical properties of applied irrigation water SO₄² (mg l -1 ) HCO3 - (mg l -1 ) CO3 2- (mg l -1 ) Cl (mg l -1 ) Mg (mg l -1 ) 550.5 159 0.0 435.3 241.6 Ca (mg l -1 ) K (mg l -1 ) Na (mg l -1 ) EC (dS m -1 ) pH 400 2.74 152 2.7 7.2 Acta agriculturae Slovenica, 117/2 – 2021 3 Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters 2.2 METHODS 2.2.1 Growth parameters and yield Number of fruit per plant, diameter of fruit, height of plant, average mass of fruit, length of fruit, leaf area and yield were measured as growth parameters in harvest stage. Average mass of fruit was recorded by using digital scale (EK3000I). Leaf area was measured by using digital scanner (E84-10017) and imageJ software (V3). 2.2.2 Physiological characteristics Total chlorophyll and carotenoid content, titratable acidity, tissue firmness, ascorbic acid and total soluble solids of fruits were measured as physiological character- istics. Total chlorophyll and carotenoid content of leaves was determined by measuring absorption with a spectro- photometer at 645 and 663 nm for chlorophyll content and 480 and 510 nm for carotenoid content (spectropho- tometer-SAFAS UVmc2) as described by Arnon (1967). For evaluating of titratable acidity, tissue of eggplant fruit (10 g) was homogenized in 40 ml distilled water and fil- tered to extract the juice. 2 to 5 drops of phenolphthalein were added in this juice. A 10 ml aliquot was taken in a titration flask and titrated against 0.1N NaOH till perma- nent light pink color appeared. Three consecutive read- ings were taken from each replication of a treatment and percent acidity as malic acid was calculated by using the following formula: % T A=[E×N×S×F/C]×100 (R a j a et a l . 2105). (E: Equivalent wt. of malic acid) (N: Normality of NaOH) (S: ml NaOH used) (F: vol. of aliquot taken) (C: wt. of sample). Fruit firmness was measured with penetrometer (FT-327-48011-Alfonsine-Italy) and expressed pressure necessary to force a plunger of 11 mm size into the fruit (Arvanitoyannis et al., 2005). Ascorbic acid content of fruit was determined by applying of iodometric titration method according to V anderslice et al. (1990). T otal solu- ble solids was evaluated by using refractometer (ATAGO Brixo-32) and expressed as degrees brix (Paull and Chen, 1989). 2.2.3 Post-harvest characteristics Following properties were analyzed to evaluate post-harvest characteristics of eggplant fruits (during storage): titratable acidity, tissue firmness, ascorbic acid, soluble solids content, fruit mass loss, fruit decay and browning of pulp tissue. Fruit mass loss: Mass loss was determined by the following formula: Mass loss (%)=[(A-B)/A] × 100 Where A indicates the fruit mass at the time of har- vest and B indicates the fruit mass after storage intervals (Huang et al., 2000). Fruit decay: Fruit decay percent was estimated by visual scoring method, as described by Kader et al. (2010) on 1-4 scale, with reference points of: 4 = severe; 3 = moderate; 2 = slight; 1 = none. The score attribution depends on morphological effects such as color change, microorganism effects and smell. Browning of pulp tissue: The color parameter L* in- dicates the lightness of color (0 = black and 100 = whi- te). A Minolta Colorimeter model CR-300 was used to determine L*, and the readings were taken soon after slicing the central section of each fruit (thickness = 0.5 cm). All measurements were done on three fruits from each condition and by duplicate. The results were expres- sed as L 0 , values higher than 86 denotes whitish pulp and values between 81 and 82 show only seed browning. Lightness near to 78 indicates an incipient browning of seed and pulp, while values below 73 denote considerable browning of seed and pulp (Ahmad et al., 2013). 2.3 STUDY DESIGN Factorial experiment was laid out based on random- ized complete blocks design (to evaluate growth param- eters and physiological characteristics in harvest stage) and completely randomized design (to evaluate post- harvest characteristics during storage) with three repli- cations. The factors are foliar application of CL and SA in different concentrations including three levels for CL solution: 0 mM (control), 2 mM (0.4 g L -1 ) and 4 mM (0.8 g L -1 ) and three levels for SA solution: 0 mM (control), 1 mM (0.13 g L -1 ) and 1.5 mM (0.2 g L -1 ) and also during of storage in three levels including: 10, 20 and 30 days. CL and SA foliar application was carried out at 6-leaf stage for the first time and continued at 10-day intervals until harvest stage. 2.4 STATISTICAL ANALYSIS Data were analyzed by analysis of variance (ANO- VA) using the SAS software (V9). Mean comparisons were performed by Duncan’s multiple range test at confi- dence level of 95 %. Acta agriculturae Slovenica, 117/2 – 2021 4 Z. GHAHREMANI et al. 3.1 GROWTH PARAMETERS AND YIELD According to ANOV A analysis, significant influence of CL and SA foliar application and interaction between them on all of measured growth parameters was found. Table 3 shows, the highest applied concentrations of CL (4 mM) and SA (1.5 mM) foliar application led to the highest values in all of measured growth parameters. Also, the highest value of yield (127.21 t ha -1 ) was record- ed in plants sprayed by CL 4 mM and SA 1.5 mM. Yield increased by 13.46 % at sprayed plants by CL 4 mM and SA 1 mM compared to CL 2 mM and SA 1 mM treated plants. Similar stimulatory effects of SA and different types of calcium sources (calcium oxide, calcium chlo- ride, calcium chelate and calcium lactate) on different growth parameters were reported in tomato (Rab & Haq, 2012), strawberry (Kazemi, 2013a), cucumber (Kazemi, 2013b), cowpea (Mohamed & Basalah, 2015) and lettuce (Almeida et al., 2016; Khani et al., 2020). SA stimulates the growth and development of roots of the treated plants by increasing of H + -ATPase enzyme activity and root ATP content (Ghassemi-Golezani and Farhangi-Abriz, 2018) thereby improving nutrient uptake. So, increasing of nutrient uptake rate can be as important reason for increasing of growth parameters and yield in SA treated plants. According to Hepler (1994), the effects of differ- ent calcium sources on growth parameters of different crops can be related to the fact that calcium ions (Ca 2+ ) appeared to participate in the regulation of different aspects of cell division. Calcium is one of the most im- portant ions in formation of the mitotic spindle which directly affects cell division. 3.2 PHYSIOLOGICAL CHARACTERISTICS All of the measured physiological characteristics were significantly affected by CL and SA foliar applica- tion and interaction between them. The highest chloro- phyll content (1.32 mg g FM -1 ) was related to sprayed plants by CL 4 mM and SA 1 mM and the lowest carot- enoid content (0.36 mg g FM -1 ) was obtained in control (sprayed plants by CL 0 mM and SA 0 mM) (Table 4). Foliar application of SA was found to increase the chloro- phyll content in cowpea (Chandra & Bhatt, 1998), toma- to (Kalarani et al., 2002), cucumber (Yildirim et al., 2008) and strawberry (Karlidag et al., 2009a, 2009b). Martin- Diana et al. (2005), reported that carotenoid levels were higher in CL-treated carrots than that in control samples at the end of 10 days storage. Results showed that, the highest and lowest values of total soluble solids were re- lated to control fruits (harvested from sprayed plants by CL 0 mM and SA 0 mM) and harvested fruits from CL 4 mM and SA 0 mM sprayed plants, respectively. Foliar ap- plication of CL and SA led to a significant reduction in total soluble solids of fruits. Different results were report- ed about effect of calcium sources on total soluble solids of fruits, for instance, according to Akhtar et al. (2010), CC treatment could significantly increase total soluble solids in Loquat fruit but in contrast, Dong et al. (2004) reported that, total soluble solids of tomato reduced by employing of calcium treatment. Calcium sources and SA treatments lead to a decrease in respiration rate, eth- ylene biosynthesis and ripening of fruits, which in turn decrease the polysaccharide degradation in cell wall and cell membrane. So, decreasing of polysaccharide degra- dation can lead to a reduction of total soluble solids of fruits. Titratable acidity increased by 2.86 % at harvested fruits from CL 4 mM and SA 1.5 mM sprayed plants compared to fruits of treated plants by CL 4 mM and SA 0 mM. Applying of CL and SA foliar treatment could increase tissue firmness and ascorbic acid content of fruits and CL 4 mM and SA 1.5 mM foliar spraying was the best treatment to increase tissue firmness and ascor- bic acid content of eggplant fruits. Fruit softening results from cell wall degradation by cell wall hydrolases such as polygalactosidases, pectin methylesterases, b-galacto- sidase and xylanase along with cell membrane deteriora- tion. As an ethylene inhibitor, SA delays fruit ripening and prevents fruit softening by reducing the activity of cell wall-degrading enzymes. Srivastava and Dwivedi (2000) reported that SA reduced polygalactosidases, xy- lanase, and cellulase enzyme activity in harvested banana fruits. Wang et al. (2006) reported that SA treatment can increase ascorbic acid content in fruit and vegetable crops by increasing of ascorbate peroxidase enzyme ac- tivity. Our finding with respect to the effect of CL and SA foliar application on ascorbic acid content is in line with those reported by Elvwan and Hamahyomy (2009). They observed an increase in ascorbic acid content of green- house pepper by employing of low concentration of SA foliar application. 3 RESULTS AND DISCUSSION Acta agriculturae Slovenica, 117/2 – 2021 5 Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters Table 3: Effect of CL and SA foliar application on growth parameters and yield at harvest SA concentration (mM) CL concentration (mM) Leaf area (mm) Average mass of fruits (g) Number of fruit per plant Diameter of fruit (cm) Length of fruit (cm) Height of plant (cm) Yield (t ha -1 ) 0 185.4f 255.66f 11.23g 3.54f 19.35f 63.11h 95.57g 0 2 192.32d 262.66e 11.41f 3.65e 19.73ef 64.21g 99.72f 4 196.12c 275.66c 12.03c 3.83d 20.12e 66.59e 110.06c 0 191.59d 269.33d 11.64e 3.84d 21.47d 65.42f 104.16e 1 2 195.29c 273.66c 11.05h 3.94c 22.57bc 67.39e 100.31f 4 199.19b 280b 12.43b 4.25b 23.28b 72.59c 115.89b 0 188.64e 274c 11.82d 3.82d 21.60d 70.03d 107.48d 1.5 2 200.89b 282.66b 12.38b 3.91c 22.40c 74.18b 115.42b 4 207.45a 297.33a 12.84a 4.42a 24.08a 81.77a 127.21a Values in columns for same variable followed by the same letter are not significantly different according to Duncan’s multiple range test (p ≤ 0.05) 3.3 POST-HARVEST CHARACTERISTICS According to ANOVA analysis, all of the measured post-harvest characteristics except fruit decay were af- fected by interaction between CL and SA foliar applica- tion and duration of storage. Figure 1 shows the effect of interaction between CL and SA treatment and duration of storage on total soluble solids, titratable acidity, tissue firmness and ascorbic acid content of fruits. Total soluble solids of fruits raised by increasing the time of storage from 10 to 20 days but a reverse trend (reduction) was detected in total soluble solids of fruits from 20 to 30 days of storage. In our opin- ion, change in ratio of respiration rate (consumption of sugars) to conversion of starch to sugar (production of sugars) would be a main reason on increasing of total sol- uble solids in first days of storage with a peak on 20 days of storage and then decreasing until 30 days after storage. The rate and speed of conversion of starch to sugar (pro- duction of sugars) is higher than respiration rate (con- sumption of sugars) in first days of storage and it can lead to a significant increase in total soluble solids of fruits SA concentration (mM) CL concentration (mM) Chlorophyll content (mg g FM -1) Carotenoid content (mg g FM -1) Total soluble solids (0B) Titratable acidity (%) Tissue firmness (N) Ascorbic acid content (mg 100 g Juice) 0 0.80h 0.36h 5.07a 5.45e 3.23f 1.75e 0 2 0.93f 0.39g 4.87b 5.47de 2.76ef 1.70e 4 1.25c 0.45d 4.18g 5.44e 2.64c 1.83d 0 1.01e 0.42f 4.78c 5.49cd 3.00d 1.82d 1 2 1.05d 0.44e 4.67d 5.50bcd 3.37b 1.90c 4 1.32a 0.51c 4.46e 5.52b 3.41ab 1.94bc 0 0.87g 0.39g 4.82bc 5.52bc 2.92de 1.90c 1.5 2 0.94f 0.62a 4.53e 5.53b 3.29bc 1.99b 4 1.29b 0.59b 4.34f 5.60a 3.54a 2.07a Values in columns for same variable followed by the same letter are not significantly different according to Duncan’s multiple range test (p ≤ 0.05) Table 4: Effect of CL and SA foliar application on the content of metabolites and firmness at harvest Acta agriculturae Slovenica, 117/2 – 2021 6 Z. GHAHREMANI et al. but the ratio of respiration rate to conversion of starch to sugar increased after 20 days of storage, so a signifi- cant decrease was detected in total soluble solids of fruits in the last days of storage. (Figure 1a). The highest value of titratable acidity (5.53 %) was obtained in harvested fruits from sprayed plants by CL 4 mM and SA 1.5 mM after 10 days of storage (Figure 1b). During storage, there is conversion of starch to sugar and the oxidation of or- ganic acids to sugar which rapidly reduce the titratable acidity and increase total soluble solids of fruits (Camp- estre et al., 2002). Tissue firmness reduced by increas- ing the time of storage but harvested fruits from treated plants showed higher value of tissue firmness than that in control (Figure 1C). According to Mahajan et al. (2017), the reduction of fruit firmness during post-harvest stage is mainly caused due to the dissolution of the middle la- mella, decreasing of cell-to-cell adhesion and the weak- ening of parenchyma cell walls as a result of the action of cell wall modifying enzymes leading to shriveling and softening. We guess the inhibitory effect of CL and SA on degrading enzymes activity can be as main reason for positive effect of foliar treatment on fruit tissue firmness Figure 1: Effect of CL and SA foliar application and during of storage on: a total soluble solids, b titratable acidity, c tissue firmness and d ascorbic acid content Values in columns for same variable followed by the same letter are not significantly different according to Duncan’s multiple range test (p ≤ 0.05) Acta agriculturae Slovenica, 117/2 – 2021 7 Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters Figure 2: Effect of CL and SA foliar application and during of storage on: a browning percent and b mass loss Values in columns for same variable followed by the same letter are not significantly different according to Duncan’s multiple range test (p ≤ 0.05) in this study. The highest and lowest values of ascorbic acid content were related to harvested fruits from CL 2 mM and SA 1.5 mM sprayed plants after 10 days of stor- age and control fruits after 30 days of storage (1.78 and 0.58 mg.100g juice, respectively) (Figure 1d). Our results showed that ascorbic acid content of fruits reduced by increasing of duration of storage but foliar treatment led to a reduction in ascorbic acid decreasing rate. Accord- ing to Umebese and Bankole (2013), SA foliar application can increase nitrate reductase enzyme activity and this enhancement corresponds with the reduction of ascorbic acid decreasing rate. Figure 2 shows the effect of CL and SA treatment and duration of storage on pulp tissue browning and fruit mass loss. The highest and lowest values of pulp tis- sue browning were related to control fruits after 30 days of storage and harvested fruits from CL 4 mM and SA 1.5 mM sprayed plants after 10 days of storage (89.27 and 67.16 % respectively) (Figure 2a). The best treatment to minimize fruit mass loss was CL 4 mM and SA 1 mM foliar spraying after 10 days of storage (6.75 %) (Figure 2b). Our findings with respect to the effect of CL and SA treatment and duration of storage on fruit mass loss showed that control fruits re- corded maximum fruit mass loss after 30 days of stor- age (19.54 %). In this study, increasing of duration of storage led to a raise in fruit mass loss. Fruit mass loss is basically related to water loss and this essentially due to transpiration, which accounts for 90 % of total mass loss and initially comes from the peel. Water loss adversely affects the quality and limits the economic post-harvest life of crops (Ennab et al., 2020). Our findings showed that foliar treatment led to a reduction in fruit mass loss. The result of this study is similar to the findings reported by Gupta et al. (2011). They reported that reduction in physiological mass loss in calcium sources treated fruits might be due to the maintenance of fruit firmness and tissue rigidity by decreasing the enzyme activity respon- sible for disintegration of cellular structure, which de- creases the gaseous exchange. According to ANOVA analysis, percent of fruit de- cay was conditioned by interaction between CL and SA foliar application and also main effect of duration of stor- age. Obtained results showed that the best treatment to decrease fruit decay was CL 4 mM and SA 1 mM foliar application (1.9 %) and 10 days storage led to the lowest Acta agriculturae Slovenica, 117/2 – 2021 8 Z. GHAHREMANI et al. 4 CONCLUSION Our results showed that foliar application of CL and SA can be useful and inexpensive treatment to improve growth parameters, physiological characteristics and post-harvest properties of eggplant fruit. The highest ap- plied concentrations of CL and SA (4 mM and 1.5 mM) foliar application led to the highest values in all of mea- sured growth parameters such as leaf area, mass, number, diameter and length of fruit, height of plant and yield. Foliar spray of eggplants by CL at 4 mM and 2 mM and also SA at 1 mM and 1.5 mM led to a significant increase in photosynthetic pigments. The highest tissue firmness and ascorbic acid content of eggplant fruit was obtained by highest concentration foliar application of CL and SA. Also, negative effects of increasing of storage time on post-harvest properties decreased by employing of CL and SA foliar application. Using of higher concentrations of SA and CL as well as applying of other plant bio-reg- ulator in eggplant cultivation is recommended for future researches. 5 REFERENCES Ahmad, S., Singh, Z., Khan, A. S,, & Iqbal, Z. (2013). Prehar- vest applications of salicylic acid maintain the rind textural properties and reduce fruit rot and chilling injury of sweet orange during cold storage. Pakistan Journal of Agriculture Science, 50, 559-569. Akhtar, A., Abbasi, N. A., & Hussain, A. (2010). Effect of cal- cium chloride treatments on quality characteristics of Lo- quat fruit during storage. Pakistan Journal of Botany, 42, 181-188. Almeida, P. H., Mógor, A. F., Ribeiro, A. Z., Heinrichs, J., & Amano, E. (2016). Increase in lettuce (Lactuca sativa L.) production by foliar calcium application. Australian Jour- nal of Basic and Applied Sciences, 10(1016), 161-167. Arnon, A. N. (1967). Method of extraction of chlorophyll in the plants. Agronomy, 23, 112-121. Arvanitoyannis, I., Khan, E. M., Evangelia, C. C., & Bletsos, F. A. (2005). Effect of grafting and modified atmosphere packaging on eggplant parameters during storage. Interna- tional Journal of Food Science & Technology, 40(3), 311-322. https://doi.org/10.1111/j.1365-2621.2004.00919.x Campestre, C., Marsilio, V ., Lanza, B., Lezzi, C., & Bianchi, G. (2002). Phenolic compounds and organic acids change in black oxidized table olives. Acta horticulturae, 586, 575- 578. https://doi.org/10.17660/ActaHortic.2002.586.120 Chandra, A., & Bhatt, R. K. (1998). Biochemical and physiolog- ical response to salicylic acid in relation to the systemic ac- quired resistance. Photosynthetica, 35(2), 255-258. https:// doi.org/10.1023/A:1006966908357 Dong, C. X., Zhou, J. M., Fan, X. H., & Wang, H. Y . (2004). Ap- plication methods of calcium supplements affect nutrient levels and calcium forms in mature tomato fruits. Journal of Plant Nutrition, 27, 1443-1455. https://doi.org/10.1081/ PLN-200025861 Elvwan, M. W . M., & Hamahyomy, M. A. M. (2009). Improved fruit decay percent (1.28 %) (Table 6). SA and calcium sources significantly reduced fruit decay of stored man- darins and sweet oranges due to enhancing the activity of antioxidant enzymes and improving resistance to fungal attack, the accumulation of H 2 O 2 and defense-related me- tabolites like ornithine, threonine and polymethoxylated Table 5: Effect of CL and SA foliar application and duration of storage on fruit decay after harvest SA concentration (mM) CL concentration (mM) Fruit decay (%) Duration of storage (day) Fruit decay (%) 0 2.58a 10 1.28c 0 2 2.15cd 20 2.20b 4 2.03de 30 3.10a 0 2.36b 1 2 2.12cd 4 1.93e 0 2.18cd 1.5 2 2.17cd 4 2.22bc Values in columns for same variable followed by the same letter are not significantly different according to Duncan’s multiple range test (p ≤ 0.05) flavones (Zhu et al., 2016), and the anti-senescent effect that maintains fruit firmness, which eventually reduced microbial attack (Ahmed et al., 2013). Pre-harvest treat- ment of SA reduced post-harvest fruit decay and fungal diseases in melon (Huang et al., 2000), mango (Zainuri et al., 2001) and apple (Krishna et al., 2012). Acta agriculturae Slovenica, 117/2 – 2021 9 Calcium lactate and salicylic acid foliar application influence eggplant growth and postharvest quality parameters productivity and quality assocated with salicylic acid ap- plication in greenhouse pepper. Scientia Horticulturae, 122, 521-526. https://doi.org/10.1016/j.scienta.2009.07.001 Ghahremani, Z., Mikaealzadeh, M., Barzegar, T., and Ranjbar M. E. (2020). Foliar application of ascorbic acid and gam- ma aminobutyric acid can improve important properties of deficit irrigated cucumber plants (Cucumis sativus cv. Us), Gesunde Pflanzen. https://doi.org/10.1007/s10343-020- 00530-6 https://doi.org/10.1007/s10343-020-00530-6 Ghassemi-Golezani, K., & Farhangi-Abriz, S. (2018). Foliar sprays of salicylic acid and jasmonic acid stimulate H + - ATPase activity of tonoplast, nutrient uptake and salt tol- erance of soybean. Ecotoxicology and Environmental Safety, 166, 18-25. https://doi.org/10.1016/j.ecoenv.2018.09.059 Gupta, N., Jawandha ,S. K., & Gill, P . S. (2011). Effect of calci- um on cold storage and post-storage quality of peach. Food Science and Technology, 48(2), 225-229. Hepler, P. K. (1994). The roll of calcium in cell division. Cell Calcium, 16(4), 322-330. https://doi.org/10.1007/s13197- 010-0116-z ttps://doi.org/10.1016/0143-4160(94)90096-5 Huang, Y., Deverall, B. J., Tang, W . H., Wang, W ., & Wu, F. W . (2000). Foliar application of acibenzolar-S-methyle and protection of postharvest rock melons and hami melon from disease. European Journal of Plant Pathology, 106, 651- 656. https://doi.org/10.1023/A:1008767719691 Javaid, K., & Misgar, F. A. (2017). Effect of foliar application of salicylic acid and prohexadione-calcium on leaf nutrient content of apple cv. Red Delicious. Advance Research Jour- nal of Multidisciplinary Discoveries, 20(6), 27-29. Kader, A., & Lindberg, S. (2010). Cytosolic calcium and pH sig- naling in plants under salinity stress. Plant Signal Behavior, 5, 233-238. https://doi.org/10.4161/psb.5.3.10740 Kalarani, M. K., Thangaraj, M., Sivakumar, R., & Mallika, V. (2002). Effect of salicylic acid on tomato (Lycopersion es- culentum) productivity. Field Crop Research Journal, 23, 486-492. Karlidag, H., Yildirim, E., & Turan, M. (2009a). Exogenous ap- plications of salicylic acid affect quality and yield of straw- berry grown under anti-frost heated greenhouse condition. Journal of Plant Nutrition and Soil Science, 172, 270-276. https://doi.org/10.1002/jpln.200800058 Karlidag, H., Yildirim, E., & Turan, M. (2009b). Salicylic acid ameliorates the adverse effect of salt stress on strawberry. Scientia Agricola, 66, 180-187. https://doi.org/10.1590/ S0103-90162009000200006 Kaushik, P . (2019). Line × T ester analysis for morphological and fruit biochemical traits in eggplant (Solanum melongena L.) using wild relatives as testers. Agronomy, 9(4), 185-194. https://doi.org/10.3390/agronomy9040185 Kazemi, M. (2013a). Foliar application of salicylic acid and cal- cium on yield, yield component and chemical properties of strawberry. Bulletin of Environment, Pharmacology and Life Sciences, 2(11), 19-23. Kazemi, M. (2013b). Response of cucumber plants to foliar application of calcium chloride and paclobutrazol under greenhouse conditions. Bulletin of Environment, Pharma- cology and Life Sciences, 2(11), 15-18. Kazemi, M., Aran, M., & Zamani, S. (2011). Effect of calcium chloride and salicylic acid treatments on quality charac- teristics of kiwifruit (Actinidia Deliciosa) during storage. American Journal of Plant Physiology, 6(3), 183-189. https:// doi.org/10.3923/ajpp.2011.183.189 Khani, A., Barzegar, T., Nikbakht, J., & Ghahremani, Z. (2020). Effect of foliar spray of calcium lactate on the growth, yield and biochemical attribute of lettuce (Lactuca sativa L.) un- der water deficit stress. Advances in Horticultural Science, 34(1), 11-24. Kowalska, L., & Smolen, S. (2012). Effect of foliar application of salicylic acid on the response of tomato plants to oxida- tive stress and salinity. Journal of Elementology, 18, 239-254. https://doi.org/10.5601/jelem.2013.18.2.04 Krishna, H., Das, B., Attri, B. L., Kumar, A., & Ahmed, N. (2012). Interaction between different pre-harvest and postharvest treatments on shelf life extension of ‘Oregon Spur’ apple. Fruits, 67, 31-40. https://doi.org/10.1051/fruits/2011064 Mahajan, B. V . C., Gill, K. S., & Dhaliwal, H. S. (2017). Effect of storage period on various physiological, biochemical and enzymatic parameters of guava (Psidium guajava L.) fruit. Journal of Experimental Biology and Agricultural Sciences, 5, 846-851. https://doi.org/10.18006/2017.5(6).846.851 Martin-Diana, A., Rico, D., Barry-Ryan, C., Jesu, M. F., Mulca- hy, J., & Gary, T. M. (2005). Comparison of calcium lactate with chlorine as a washing treatment for fresh-cut lettuce and carrots: quality and nutritional parameters. Food and Agriculture, 85(13), 2260-2268. https://doi.org/10.1002/ jsfa.2254 Mohamed, A. K., & Basalah, M. O. (2015). The active role of calcium chloride on growth and photosynthetic pigments of cowpea (Vigna unguiculata L.) under salinity stress con- ditions. American-Eurasian Journal of Agricultural & Envi- ronmental Sciences, 15(10), 2011-2020. Mustafavi, S. H., Badi, H. N., Sekara, A., & Al, E. (2018). Poly- amines and their possible mechanisms involved in plant physiological processes and elicitation of secondary me- tabolites. Acta Physiologiae Plantarum, 40, 102-112. https:// doi.org/10.1002/jsfa.2254 Paull, R. E., and Chen, N. J. 1989. Waxing and plastic wraps influence water-loss from papaya fruit during storage and ripening. Journal of American Society of Horticulture Sci- ence, 114, 937-942. Rab, A., & Haq, I. (2012). Foliar application of calcium chloride and borax influences plant growth, yield, and quality of to- mato (Lycopersicon esculentum Mill.) fruit. Turkish Journal of Agriculture, 36, 695-701. Raja, R. H. S., Bhat, Z. A., Malik, A. R., & Shafi, R. H. (2015). Interrelationship between fruit quality and pre-harvest cal- cium chloride treatment on peach. International Journal of Agriculture, Environment and Biotechnology, 8(1), 103-109. https://doi.org/10.5958/2230-732X.2015.00014.5 Ranjbar, M. E., Olfati, J. A., & Amani, M. (2017). Influence of enriched soaking water on shiitake mushroom yield and properties. Acta Agriculturae Slovenica, 109(3), 555-560. https://doi.org/10.14720/aas.2017.109.3.07 Shaarawi, S. A., Salem, A. S., Elmaghraby, I. M., & ABD El- Moniem, E. A. (2016). Effect of salicylic Acid, calcium chlo- ride and calcium lactate applications on quality attributes of minimally-processed ’Wonderful’ pomegranate arils. Acta agriculturae Slovenica, 117/2 – 2021 10 Z. GHAHREMANI et al. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 44(2), 508-517. C https://doi.org/10.15835/nbha44210534 Uzunova, A., & Popova, L. (2000). Effect of salicylic acid on leaf anatomy and chloroplast ultrastructure of bar- ley plants. Photosynthetica, 38, 243–250. https://doi. org/10.1023/A:1007226116925 Vanderslice, J. T., Higgs, D. J., Hayes, J. M., & Block, G. 1990. Ascorbic acid and dehydroascorbic acid content of food- aseaten. Journal of Food Composition and Analysis, 3, 105- 118. https://doi.org/10.1016/0889-1575(90)90018-H Wang, L., Chen, S. H., Kong, W., Li, S. H., & Archbold, D. (2006). Salicylic acid pretreatment alleviates chilling injury and affects the antioxidant system and heat shock proteins of peaches during cold storage. Postharvest Biology and Technolog y, 41, 244-251. https://doi.org/10.1016/j.posthar- vbio.2006.04.010 Yildirim, E., T uran, M., & Guvenc, I. (2008). Effect of foliar sali- cylic acid applications on growth, chlorophyll and mineral content of cucumber (Cucumis sativus L.) grown under salt stress. Journal of Plant Nutrition, 31, 593-612. https://doi. org/10.1080/01904160801895118 Youssef, S., Abd Elhady, S., Abu El-Azm, N., & El-Shinawy, M. (2017). Foliar application of salicylic acid and calcium chlo- ride enhances growth and productivity of lettuce (Lactu- ca sativa). Egyptian Journal of Horticulture, 44(1), 1-16. https://doi.org/10.21608/ejoh.2017.892.1000 Zainuri, J. D. C., Wearing, A. H., Coates, L., & Terry, L. (2001). Effects of phosphonate and salicylic acid treatments on an- thracnose disease development and ripening of ‘Kensing- ton Pride’ mango fruit. Australian Journal of Experimental Agriculture, 41, 805-813. https://doi.org/10.1071/EA99104 Zhu, F ., Chen, J., Xiao X., Zhang, M., Y un, Z., & Zeng, Y . (2016). Salicylic acid treatment reduces the rot of postharvest cit- rus fruit by inducing the accumulation of H2O2, primary metabolites and lipophilic polymethoxylated flavones. Food Chemistry, 207, 68-74. https://doi.org/10.1016/j.food- chem.2016.03.077