Bangladesh Agron. J. 2022, 25(1): 105-113 RESPONSE OF BIOCHAR ON GROWTH AND YIELD OF AMAN RICE UNDER SALT STRESS M.M. Khanam, N. Nawal, M. Hasanuzzaman, M.F. Karim and A. Rahman* Department of Agronomy, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh *Corresponding E-mail: anisur68@yahoo.com (Received: 08 June 2022, Accepted: 11 August 2022) Keywords: Salinity, biochar, aman rice, BRRI dhan62, rice yield Abstract A pot experiment was conducted in Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during aman season, 2018 to assess the effect of biochar on rice (BRRI dhan62) under salt stress conditions. The factorial experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. Three levels of salinity were used viz. Control (S0), 1600 ppm NaCl (S1), and 2800 ppm NaCl (S2) under factor A and four levels of biochar were applied viz. 0 t ha−1 (B0), 2 t ha−1 (B1), 4 t ha−1 (B2) and 6 t ha−1 (B3) under factor B. The salt materials were added on pot in two installments at 20 and 30 days after transplanting (DAT). Exposure to salinity decreased growth and yield of rice including plant height, tillers hill-1, effective tillers hill-1, grains panicle-1, 1000-grain weight, grain yield and straw yield. The magnitude of growth and yield reduction increased with increasing the salinity level. Exposure of 1600 ppm and 2800 ppm NaCl declined the grain yield of rice by 28 and 100%, respectively. Straw yield (18 and 100%, respectively) and other yield contributing parameters declined by these two levels of salinity in the same way. Application of different levels of biochar ameliorated salt- induced damages to a certain extent. Under 2800 ppm NaCl stress, application of biochar extended life duration of rice plant upto 80 DAT, whereas without biochar application rice plant died after 60 DAT. Upon exposure to 1600 ppm NaCl stress, application of 2, 4 and 6 t ha−1 of biochar increased grain yield by 37, 42 and 30%, respectively, compared with the respective salt treatments (without biochar). Biochar enhanced yield of rice under saline conditions by enhancing yield contributing attributes including effective tillers and 1000-grain weight and by reducing salt-induced damages. However, response of 4 t ha−1 of biochar was best among the biochar levels (2, 4 and 6 t ha−1 of biochar) under both saline and non-saline conditions. Introduction Rice is the second most widely grown cereal and primary source of food for more than half of the world population (Haque et al., 2015). It is adapted to a variety of climatic conditions. But continuous climate change induced various environmental stresses on plants including salinity, drought, heat, cold etc. Among the environmental factors, salinity is one of the detrimental abiotic stresses reducing crop growth and productivity (Rahman et al., 2017). Around 20% of world irrigated land are salt affected (Munns and Tester, 2008) and it is assumed that 50% of world cultivable land will be affected by salinity by 2050 (Mahajan and Tuteja, 2005). However, salinity is a major environmental threat for crop production as its negative effect starts from germination and exist till death of plant (Mahajan and Tuteja, 2005; Mishra et al., 2013). Salinity in the plant root region creates osmotic, ionic and oxidative stress in plants (Munns and Tester, 2008; Hussain et al., 2017) which ultimately reduced growth and yield of plant (Hasanuzzaman et al., 2013; Rahman et al., 2016a; Rahman et al., 2016b). Salt induced stress reduced plant height, tiller number, effective tillers, filled grain, grain yield, straw yield even causes death of plant (Hasanuzzaman et al., 2013; Islam et al., 2022). mailto:anisur68@yahoo.com 106 Khanam et al. Biochar is carbon rich fine-grained charcoal produced by pyrolysis of biomass in a low oxygen environment and it increase soil fertility (Liu et al., 2016; Zhang et al., 2019). Biochar improves physical, chemical and biological properties of soil by increasing soil organic carbon, cation exchange capacity and stabilization of soil structure (Zheng et al., 2018). Chaganti and Crohn (2015) revealed that biochar application under salt stress conditions reduces salt-induced damages by reducing Na+ uptake and increasing nutrient uptake. Biochar application decreased bulk density, electrical conductivity, exchangeable Na+ and exchangeable Cl- in soil under salt stress conditions that helps to mitigate salinity stress in rice (Zhang et al., 2019). However, Yang et al. (2021) revealed that application of 10 t ha–1 of biochar increased tropical rice production by improving soil physical properties and at the same time increased soil salinity. Application of biochar in higher rate (>10 t ha–1) decreased growth and yield of rice (Chen et al., 2021 and Yang et al., 2021). Considering the issues discussed, the present study was conducted to identify the lower rate of biochar which can play positive role on rice under salt stress conditions. Materials and Methods The experiment was conducted at Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during aman season (July to December) 2018 in net house conditions on plastic pot (14 inches diameter and 18 inches depth). The experimental pots were filled with 12 kg well dried and fertilized soil. Urea, TSP, MoP and Gypsum fertilizers were applied at the rate of 150, 50, 80 and 60 Kg ha−1 as per recommendation of Bangladesh Rice Research Institute (BRRI). Four levels of biochar were applied on plastic pot as per treatment. After growing in seedbed, 25 days old seedlings were transplanted in experimental pot. Two seedlings were transplanted in each hill and three hills set in each pot. Different intercultural operations were done as per requirement of the crop. After establishment of seedlings, three levels of NaCl were added on pot in two equal installments at 20 and 30 DAT. The experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. Three levels of salinity viz. Control (S0), 1600 ppm NaCl (S1), and 2800 ppm NaCl (S2) were under factor A and four levels of biochar viz. 0 t ha−1 (B0), 2 t ha−1 (B1), 4 t ha−1 (B2) and 6 t ha−1 (B3) were under factor B. All plants from each pot were considered for different growth, yield and yield contributing parameters like plant height, tiller hill-1, effective tillers hill-1, grains panicle-1, 1000-grain weight, grain yield and straw yield. The collected data analyzed by Statistix 10 software by following two-way ANOVA model and mean separation was done by least significant difference (LSD) test at the 5% level of significance. Results and Discussion Plant height Salinity significantly influenced plant height of rice (Table 1). In response to 1600 ppm NaCl stress, rice plant showed statistically similar plant height compared with control. Upon exposure to 2800 ppm NaCl, the plant height of rice declined by 19, 48, 71 and 100% at 40, 60 and 80 DAT, and at harvest, respectively, compared with untreated control. Our results in agreement with Islam et al. (2022) who stated that salinity decreased plant height of rice and magnitude of decreases increased with the advancement of the growth period. Under saline conditions, Na+ enter into shoot of rice through apoplastic pathway which disrupts cell division and cell elongation and ultimately reduced growth of rice (Hussain et al., 2017). Biochar application had significant influence on plant height of rice upto 40 DAT (Table 1). AT 20 DAT, the longest plant recorded for the application of 4 t ha−1 of biochar. Application of 2 and 6 t ha−1 of biochar had no impact on plant height compared with control at 20 DAT. At 40 DAT, the longest plant recorded for the application of 6 t ha−1 of biochar. Biochar application influenced plant height of rice under salt stress conditions (Table 1). Upon exposure to 1600 ppm NaCl, all treatment combinations showed statistically similar plant height. Under 2800 ppm NaCl stress conditions, rice plant survived upto 60 DAT without biochar application, Response of Biochar on Growth and Yield of Aman Rice 107 whereas rice plant survived upto 80 DAT when combined with biochar application. Upon exposure to 2800 ppm NaCl, plant height increased by 56, 68 and 76%, respectively at 60 DAT for the application of 2, 4 and 6 t ha−1 of biochar. Table 1. Effect of NaCl and biochar on plant height of aman rice (BRRI dhan62) Treatments Plant height (cm) 20 DAT 40 DAT 60 DAT 80 DAT At harvest Effect of NaCl S0 45.36 63.64 a 87.17 a 87.96 a 86.8 a S1 45.278 62.06 a 79.35 a 86.67 a 85.99 a S2 45.22 51.36 b 45.45 b 25.34 b 0 b LSD(0.05) NS 3.63 14.68 12.49 4.73 CV (%) 7.07 8.54 28.88 26.05 11.43 Effect of biochar B0 45.24 ab 56.42 b 64.789 57.05 b 58.691 B1 43.47 b 56.64 b 71.237 69.99 ab 57.762 B2 46.597 a 59.73 ab 72.649 75.99 a 59.118 B3 45.833 ab 63.28 a 73.948 63.59 ab 54.824 LSD(0.05) 2.66 4.19 NS NS NS CV (%) 7.07 8.54 28.88 26.05 11.43 Combined effect of NaCl and biochar S0B0 44.27 a-c 61.25 bc 87.21 a 87 a 86.74 a S0B1 45.85 ab 63.43 a-c 85.52 a 87.42 a 87.26 a S0B2 48.28 a 68.11 ab 88.09 a 91.50 a 89.67 a S0B3 42.49 bc 61.78 bc 87.86 a 85.92 a 83.53 a S1B0 45.53 ab 58.85 c 76.85 a-c 84.15 a 89.33 a S1B1 43.74 a-c 56.96 c 80.90 ab 89.32 a 86.03 a S1B2 44.74 a-c 63.38 a-c 78.98 a-c 86.10 a 87.69 a S1B3 47.44 a 69.05 a 80.66 ab 87.12 a 80.95 a S2B0 45.93 ab 49.17 d 30.31 d 0 e 0 b S2B1 40.83 c 49.54 d 47.29 d 33.25 bc 0 b S2B2 46.78 ab 47.72 d 50.88 cd 50.38 b 0 b S2B3 47.58 a 59.03 c 53.33 b-d 17.75 cd 0 b LSD(0.05) 4.61 7.25 29.31 24.98 9.47 CV (%) 7.07 8.54 28.88 26.05 11.43 Here, S0= 0 ppm NaCl S1= 160 ppm NaCl S2= 280 ppm NaCl B0= 0 t ha−1 Biochar B1=2 t ha−1 Biochar B2= 4 t ha−1 Biochar B0= 6 t ha−1 Biochar NS= Non significant Tillers hill−1 Exposure to NaCl stress declined the tillers hill−1 in entire life of rice except 20 DAT (Table 2). At 40 DAT, application of 1600 and 2800 ppm NaCl declined the tillers hill−1 of rice by 11% and 46 %, respectively, compared with control. Upon exposure to 1600 and 2800 ppm NaCl, the tillers hill−1 of rice declined at 60 DAT (12% and 76%, respectively), 80 DAT (8% and 86%, respectively) and at harvest (11% and 100%, respectively) in the same way. The present study revealed that the magnitude of tiller decreasing trend increased with the advancement of the growth period and increment of the salinity level. The immediate response of salinity to plant is osmotic and ionic stress which reduces cell elongation, cell division, stomatal closure and leaf area as well as photosynthesis, plant height and tiller number (Rahman et al., 2017). The number of tillers hill−1 of rice enhanced by different levels of biochar application (2, 4 and 6 t ha−1) at 20 DAT, 80 DAT and at harvest (Table 2). At 40 and 60 DAT, Biochar had no impact on tiller production or on mortality. 108 Khanam et al. Interaction effect of biochar and salinity had significant impact on tiller production at 60 DAT, 80 DAT and at harvest (Table 2). Under controlled conditions, biochar treated plant produced statistically similar number of tiller hill-1 throughout the growth period of rice. In response to 2800 ppm NaCl, all tillers of rice plant died without biochar application at 80 DAT whereas few tillers remained alive for the application of 2, 4 and 6 t ha−1 of biochar. At harvesting time, no tiller remained alive in response to 2800 ppm NaCl irrespective of biochar levels. Table 2. Effect of NaCl and biochar on number of tiller hill−1 of aman rice (BRRI dhan62) Treatments Tiller hill−1 (No.) 20 DAT 40 DAT 60 DAT 80 DAT At harvest Effect of salt S0 5.1913 12.12 a 12.49 a 11.18 a 10.41 a S1 5.3856 10.83 b 10.94 a 10.32 a 9.29 b S2 5.3437 6.59 c 2.94 b 1.53 b 0 c LSD(0.05) NS 1 1.57 1.15 0.7 CV (%) 15.13 14.15 24.84 20.76 14.75 Effect of biochar B0 4.57 b 9.08 7.9133 6.13 c 5.63 b B1 5.35 a 9.96 8.6975 8.26 ab 6.97 a B2 5.41 a 10.47 9.5333 8.88 a 7.05 a B3 5.90 a 9.89 9.0167 7.44 bc 6.60 a LSD(0.05) 0.67 NS NS 1.32 0.8 CV (%) 15.13 14.15 24.84 20.76 14.75 Combined effect of Salt and biochar S0B0 4.51 12.25 12.97 a 10.31 ab 9.65 ab S0B1 5.19 12 12.28 ab 11.49 a 10.72 a S0B2 5.22 13 13.15 a 11.38 a 10.70 a S0B3 5.85 11.25 11.58 ab 11.56 a 10.56 ab S1B0 4.70 9.63 c 9.40 b 8.08 b 7.25 c S1B1 5.70 11.47 11.32 ab 11.55 a 10.2 ab S1B2 5.38 11.40 12.05 ab 11.90 a 10.45 ab S1B3 5.77 10.83 10.98 ab 9.750 ab 9.25 b S2B0 4.50 5.38 1.38 c 0 d 0 d S2B1 5.15 6.40 2.50 c 1.75 cd 0 d S2B2 5.65 7 3.40 c 3.38 c 0 d S2B3 6.08 7.59 4.50 c 1 d 0 LSD(0.05) NS NS 3.14 2.29 1.39 CV (%) 15.13 14.15 24.84 20.76 14.75 Effective tillers hill−1 Application of NaCl in BRRI dhan62 decreased the number of effective tillers hill−1 to a great extent (Table 3). Increase in salinity strength proportionally decreased the number of effective tillers hill−1 in rice. Exposure to 1600 and 2800 ppm NaCl decreased the number of effective tillers hill−1 by 19 and 100%, respectively, compared with control (Table 3). Our results in line with Hussain et al. (2017) who reported that salinity delayed flowering and even arrest panicle initiation by decreasing nutrient uptake, photosynthesis and ultimately reduced productive tillers. The number of effective tiller hill−1 of rice was influenced by different levels of biochar application (Table 3). The present study revealed that the number of effective tillers hill−1 of BRRI dhan62 Here, S0= 0 ppm NaCl S1= 160 ppm NaCl S2= 280 ppm NaCl B0= 0 t ha−1 Biochar B1=2 t ha−1 Biochar B2= 4 t ha−1 Biochar B0= 6 t ha−1 Biochar NS= Non significant Response of Biochar on Growth and Yield of Aman Rice 109 increased by 16 and 20% by the application of 2 and 4 t ha−1 of biochar, respectively. The present finding corroborates with Sriphirom et al. (2020) who reported that biochar application increases productive tiller and yield by increasing nutrient uptake efficiency. However, compared with control, application of 6 t ha−1 of biochar showed no impact on productive tiller production. Combined application of NaCl and biochar showed significant effect on the number of effective tillers hill−1 of rice. The highest number of effective tiller hill−1 (9.33) recorded for the application of 4 t ha−1 of biochar under controlled condition (0 ppm NaCl). At 1600 ppm NaCl stress, application of 2, 4 and 6 t ha−1 of biochar increased the effective tillers hill−1 of BRRI dhan62 by 41, 48 and 22%, respectively, compared with salt-treated alone (Table 3). Exposure to 2800 ppm NaCl stress, BRRI dhan62 failed to produce productive tillers in absence or presence of any doses of biochar. Filled grains panicle−1 Treatment of rice plant with 1600 and 2800 ppm NaCl decreased the number of filled grains panicle−1 by 15 and 100%, respectively, compared with untreated control (Table 3). The reduction of the filled grains panicle−1 was 100% under severe salinity as there was no plant alive and effective tiller production under this treatment. This result is in line with Nahar et al. (2009) who reported that increase in salinity decreased the number of filled grains panicle−1. The number of filled grains panicle−1 varied significantly for the application of different levels of biochar (Table 3). Compared with control, application of 2 and 4 t ha−1 of biochar increased the filled grains panicle−1 by 9 and 10 %, respectively. Chen et al. (2021) reported that biochar application increased the number of productive tillers, number of filled grain and grain yield of rice. Addition of 6 t ha−1 of biochar showed similar result compared with control. Interaction effect of NaCl treatment and biochar application had significant impact on the production of filled grains panicle−1 (Table 3). Under controlled condition, application of 2 and 4 t ha−1 of biochar showed no impact on the production of filled grains panicle−1. Application of 6 t ha−1 of biochar slightly decreased the number of filled grains panicle−1. However, in 1600 ppm NaCl treated rice plant, the production of the filled grains panicle−1 enhanced by 22, 28 and 20% for the application of 2, 4 and 6 t ha−1 of biochar, respectively, compared with salt treated plant alone. Upon exposure to 2800 ppm NaCl stress, BRRI dhan62 failed to produce filled grain in absence or presence of any doses of biochar. Total grains panicle−1 Imposition of 1600 and 2800 ppm NaCl decreased the number of total grains panicle−1 in rice by 26 and 100%, respectively, compared with untreated control (Table 3). Imposition of 2800 ppm NaCl caused death of all plant at harvesting time as a result reduction of total grains panicle−1 was 100% under this treatment. These results were in line with previous studies (Nahar et al., 2009; Islam et al., 2022) who reported that salinity decreases number of grains in rice. The number of total grains panicle−1 showed positive relation with biochar application in BRRI dhan62 (Table 3). When rice plants were exposed to 2, 4 and 6 t ha−1 of biochar, the production of the total grains’ panicle-1 uplift by 21, 27 and 10%, respectively, compared with control. The combination of different levels of salinity and biochar showed significant effect on the production of total grains panicle−1 (Table 3). In untreated control conditions, application of different levels of biochar, statistically produced similar number of total grains panicle−1. When rice plants were exposed to 1600 ppm NaCl with the application of 2, 4 and 6 t ha−1 of biochar, the total grains panicle−1 enhanced by 52, 64 and 33%, respectively, compared with 0 t ha−1 of biochar. In 2800 ppm NaCl stressed-plant, application of any dose of biochar failed to produce any number of grains in BRRI dhan62 as all plants died under this treatment. Thousand grains weight 110 Khanam et al. Upon exposure to 1600 ppm NaCl, 1000-grain weight reductions were insignificant compared with control (Table 3). Application of 2800 ppm NaCl caused death of all plant before harvesting time. As a result, reduction of 1000-grain weight was 100% compared with untreated control. Different levels of biochar application had non-significant influence on 1000-grain weight of BRRI dhan62. The interaction effect of NaCl and biochar had significant influence on 1000-grain weight of rice (Table 3). Under controlled conditions, application of different level of biochar showed no variation on 1000-grain weight of rice. In 1600 ppm NaCl-treated rice plant, application of different levels of biochar uplift 1000-grain weight and showed statistically similar results. Exposure of 2800 ppm NaCl caused death of all rice plant in all biochar treated rice plant. Grain yield Exposure to 1600 and 2800 ppm NaCl decreased grain yield by 28 and 100%, respectively, compared with control (Table 3). Salinity reduced grain yield in rice by decreasing yield attributes including effective tillers, number of grain and 1000-grain weight (Islam et al., 2022). The present study revealed that salinity decreased grain yield by decreasing the number of effective tiller hill−1, total grains and filled panicle−1 which is in line with previous studies (Zeng et al., 2002; Islam et al., 2022). Application of biochar increased grain yield of rice by promoting nutrient uptake (Liu et al., 2016). Yang et al. (2021) stated that biochar increased rice yield by increasing soil physical properties, soil organic carbon, nutrient uptake and maintaining soil temperature. The present study revealed that, biochar increased grain yield by increasing the number of effective tillers and filled grain. Application of 2, 4 and 6 t ha−1 of biochar enhanced grain yield of rice by 15, 18 and 10%, respectively, compared with control (Table 3). This result was in agreement with Zhang et al. (2012) who noticed that application of rice biochar at the rate of 10 t ha–1 enhanced rice grain yield by 10%. Chen et al. (2021) also stated that biochar application increased grain yield and yield attributes. Application of biochar under salt stress conditions increased grain yield of rice. Upon exposure to 1600 ppm NaCl, grain yield enhancement was 37, 42 and 30% for the application of 2, 4 and 6 t ha−1 of biochar, respectively (Table 3). However, in response to 2800 ppm NaCl, all rice plants died before harvesting time irrespective of different biochar levels. Zhang et al. (2019) revealed that biochar application reduces salt induced damages and increased rice yield under salt stress conditions. Table 3. Effect of NaCl and biochar on yield attributes and yield of rice (BRRI dhan62) Treatments Effective tillers hill−1 (No.) Filled grains panicle−1 (No.) 1000-grain wt. (g) Grain yield pot−1 (g) Straw yield pot−1 (g) Effect of salt S0 9.099 a 61.07 a 22.90 a 39.21 a 141.46 a S1 7.34 b 51.89 b 22.32 a 28.09 b 116.16 b S2 0 c 0 c 0 b 0 c 0 c LSD(0.05) 0.35 2.41 0.67 1.24 5.13 CV (%) 8.87 8.90 6.21 7.7 8.31 Effect of biochar B0 4.93 b 35.58 b 15 20.27 c 82.31 b B1 5.74 a 38.91 a 15.25 23.31 ab 85.99 ab B2 5.94 a 39.22 a 15.04 23.84 a 91.37 a B3 5.3 b 36.91 ab 14.99 22.31 b 83.81 b LSD(0.05) 0.40 2.79 NS 1.43 5.93 CV (%) 8.87 8.90 6.21 7.7 8.31 Combined effect of Salt and biochar S0B0 9.03 ab 62.65 a 23.250 a 38.66 a 141.24 a S0B1 9.09 ab 62.82 a 22.750 ab 39.58 a 141.99 a S0B2 9.33 a 61.17 ab 22.625 ab 40.19 a 145.74 a S0B3 8.95 ab 57.67 bc 22.975 ab 38.39 a 136.87 a S1B0 5.75 e 44.08 d 21.750 b 22.13 d 105.70 d S1B1 8.12 c 53.92 c 23.000 ab 30.35 bc 116.00 c Response of Biochar on Growth and Yield of Aman Rice 111 S1B2 8.5 bc 56.50 bc 22.500 ab 31.34 b 128.37 b S1B3 7 d 53.07 c 22.020 ab 28.54 c 114.56 c S2B0 0 f 0 e 0 c 0 e 0 e S2B1 0 f 0 e 0 c 0 e 0 e S2B2 0 f 0 e 0 c 0 e 0 e S2B3 0 f 0 e 0 c 0 e 0 e LSD(0.05) 0.70 4.83 1.35 2.48 10.27 CV (%) 8.87 8.90 6.21 7.7 8.31 Straw yield Straw yield of rice decreased upon exposure to different level of salinity (Table 3). Upon exposure to 1600 and 2800 ppm NaCl, straw yield of rice declined by 18 and 100%, respectively, compared with control. Salinity drastically reduced the straw yield of rice by decreasing photosynthesis, nutrient uptake (Siddique et al., 2015), and tiller number (Islam et al., 2022). The present study revealed that application of 2 and 6 t ha−1 of biochar have no impact on straw yield of rice (Table 3). However, application 4 t ha−1 of biochar in BRRI dhan62 uplifted straw yield production by 11%. The combined effect of application of biochar and NaCl had significant influence on straw yield of rice. In non-saline conditions, all level of biochar showed similar results whereas in 1600 ppm NaCl- treated rice plant, application of 2, 4 and 6 t ha−1 of biochar increased straw yield by 9, 21 and 8%, respectively. However, upon exposure to 2800 ppm NaCl, all rice plants died before harvesting time irrespective of biochar levels. Zhang et al. (2019) revealed that biochar application improved anatomical structure and ultra-structure of root which increased leaf mesophyll cell activity, photosynthetic capacity and dry matter accumulation. Conclusion Salinity decreased growth and yield of aman rice (BRRI dhan62). Exposure of 1600 and 2800 ppm NaCl decreased grain yield of rice by 28 and 100%, respectively, by decreasing the number of effective tillers, filled grain and 1000-grain weight. The magnitude of growth and yield reduction increased with increasing the salinity level. Application of 2, 4 and 6 t ha−1 of biochar facilitates to recover the salt- induced damages under 1600 ppm NaCl stress and extended life duration of rice upto 80 DAT under 2800 ppm NaCl stress. Among the different rates of biochar, application of 4 t ha−1 of biochar showed better result in ameliorating salt-induced damages and yield loss under 1600 ppm NaCl stress in rice. References Chaganti, V.N. and D.M. Crohn. 2015. Evaluating the relative contribution of physiochemical and biological factors in ameliorating a saline-sodic soil amended with composts and biochar and leached with reclaimed water. Geoderma, 259–260: 45–55. Chen, X., S. Yang, J. Ding and X. Sun. 2021. Effects of biochar addition on rice growth and yield under water-saving irrigation. Water. 13: 209. doi: 10.3390/w13020209. Hasanuzzaman, M., K, Nahar and M. Fujita. 2013. Plant response to salt stress and role of exogenous protectants to mitigate salt-induced damages. In: Ahmad, P., M.M. Azooz, M.N.V. Prasad. (eds) Ecophysiology and responses of plants under salt stress. New York: Springer. pp.25–87. Here, S0= 0 ppm NaCl S1= 160 ppm NaCl S2= 280 ppm NaCl B0= 0 t ha−1 Biochar B1=2 t ha−1 Biochar B2= 4 t ha−1 Biochar B0= 6 t ha−1 Biochar NS= Non significant 112 Khanam et al. Haque, M.M., H.R. Pramanik and J.K. Biswas, K.M. Iftekharuddaula and M. Hasanuzzaman. 2015. Comparative performance of hybrid and elite inbred rice varieties with respect to their source-sink relationship. Sci. World J. 326802. doi: 10.1155/2015/326802. Hussain, S., Z. Jun-hua, Z. Chu, Z. Lian-feng, C. Xiao-Chuang, Y. Sheng-miao, A.B. James, H. Ji-jie and J. Qian-yu. 2017. Effects of salt stress on rice growth, development characteristics, and the regulating ways: A review. J. Integr. Agric. 16(11): 2357-2374. Islam, M.R., M.M. Islam, S.C. Sarker, M.J. Ullah and A. Rahman. 2022. Performances of boro rice as affected by different concentrations of marine water. Vietnam J. Agri. Sci. 5(1): 1326-1336. Liu, Y., H. Lu, S. Yang and Y. Wang. 2016. Impacts of biochar addition on rice yield and soil properties in a cold waterlogged paddy for two crop seasons. Field Crops Res. 191: 161-167. Mahajan, S. and N. Tuteja. 2005. Cold, salinity and drought stresses: An overview. Arch. Biochem. Biophys. 444(2): 139-158. Munns, R. and M. Tester. 2008. Mechanisms of salinity tolerance. Annu. Rev. Plant Biol. 59: 651-681. Mishra, P., K. Bhoomika and R.S. Dubey. 2013. Differential responses of antioxidative defense system to prolonged salinity stress in salt-tolerant and salt-sensitive Indica rice (Oryza sativa L.) seedlings. Protoplasma. 250: 3–19. Nahar, K. and M. Hasanuzzaman. 2009. Germination, growth, nodulation and yield performance of three mungbean varieties under different levels of salinity stress. Green Farming. 2: 825-829. Rahman, A., M.S. Hossain, J.A. Mahmud, K. Nahar, M. Hasanuzzaman and M. Fujita. 2016b. Manganese- induced salt stress tolerance in rice seedlings: regulation of ion homeostasis, antioxidant defense and glyoxalase systems. Physiol. Mol. Biol. Plants. 22(3): 291-306. Rahman, A., J.A. Mahmud, K. Nahar, M. Hasanuzzaman, M.S. Hossain and M. Fujita. 2017. Salt stress tolerance in rice: emerging role of exogenous phytoprotectants. In: Li, J. (Eds.). Advances in international rice research. Rijeka, Crotia. Intech. 140-174. Rahman, A., K. Nahar, M. Hasanuzzaman and M. Fujita. 2016a. Calcium supplementation improves Na+/K+ ratio, antioxidant defense and glyoxalase systems in salt-stressed rice seedlings. Front. Plant Sci. 7: 609. doi: 10.3389/fpls.2016.00609. Siddique, A.B., M.A. Islam, M.A. Hoque, M.M. Hasan, M.T. Rahman and M.M. Uddin. 2015. Mitigation of salt stress by foliar application of proline in rice. Univers. J. Agric. Res. 3(3): 81-88. Sriphirom, P., A. Chidthaisong, K. Yagi, S. Tripetchkul and S. Towprayoon. 2020. Evaluation of biochar applications combined with alternate wetting and drying (AWD) water management in rice field as a methane mitigation option for farmers’ adoption. Soil Sci. Plant Nutr. 66(1): 235-246. Yang, Z., T. Vancov, J. Penuelas, J. Sardans, A. Singla, A.F. Alrefaei, X. Song, Y. Fang and W. Wang. 2021. Optimal biochar application rates for mitigating global warming and increasing rice yield in a subtropical paddy field. Exp. Agric. 57: 283-299. Zeng, L., M.C. Shannon and C.M. Grieve. 2002. Evaluation of salt tolerance in rice genotypes by multiple agronomic parameters. Euphytica. 127(2): 235-245. Zhang, A., R. Bian, G. Pan, L. Cui, Q. Hussain, L. Li, J. Zheng, J. Zheng, X. Zhang and X. Han. 2012. Effects of biochar amendment on soil quality, crop yield and greenhouse gas emission in a Chinese rice paddy: a field study of 2 consecutive rice growing cycles. Field Crops Res. 127: 153-160. Zhang, J., Z. Bai, J. Huang, S. Hussain, F. Zhao, C. Zhu, L. Zhu, X. Cao and Q. Jin. 2019. Biochar alleviated the salt stress of induced saline paddy soil and improved the biochemical characteristics of rice seedlings differing in salt tolerance. Soil Tillage Res. 195: 104372. doi: 10.1016/j.still.2019.104372. Zheng, H., X. Wang, L. Chen, Z. Wang, Y. Xia, Y. Zhang, H. Wang, X. Luo, and B. Xing. 2018. Enhanced growth of halophyte plants in biochar-amended coastal soil: roles of nutrient availability and rhizosphere microbial modulation. Plant Cell Environ. 41: 517–532. Response of Biochar on Growth and Yield of Aman Rice 113