Bangladesh Agron. J. 2019, 22 (1): 27-37 PERFORMANCE OF HYBRID RICE (Bio-453) IN VARIATION OF SPACING AND NUMBER OF SEEDLING PER HILL D. Chowdhury1, M. Biswas2, M.N.H. Miah1, P. Mandal1 and M.S. Hossain1* 1Department of Agronomy and Haor Agriculture, Sylhet Agricultural University, Sylhet, Bangladesh 2Department of Agro Product Processing Technology, Jessore University of Science and Technology, Jessore, Bangladesh *Corresponding E-mail: sazzadmh.aha@sau.ac.bd (Received: 25 March 2019, Accepted: 30 May 2019) Keywords: Hybrid rice, seedling hill-1, spacing, growth and yield Abstract Hybrid rice production can ensure to get more yields per unit land. The research work was carried out to evaluate the effect of number of seedling hill-1 and spacing on the growth and yield of hybrid rice line Bio-453. The experiment was laid out in a split-plot design with 3 replications at the field of Agronomy and Haor Agriculture Department of Sylhet Agricultural University, under the AEZ 20 in Kharif-II (Aman) season of 2013. Number of seedling hill-1 was assigned in the main plot and plant spacing in the sub-plot. Two levels of seedling hill-1 viz. NS1 (1 seedling hill-1) and NS2 (2 seedlings hill -1) and five levels of plant spacing viz. Sp1 (15 cm X 15 cm), Sp2 (15 cm X 20 cm) and Sp3 (20 cm X 20 cm), Sp4 (20 cm X 25 cm) and Sp5 (20 cm X 30 cm) were the treatments. Number of seedling hill-1 and plant spacing showed significant effect in yield and yield contributing parameters except days to maturity, plant height, 1000-grain weight, total tillers hill-1, number of effective tillers hill-1, harvest index and grains panicle-1. Maximum grain yield (9.43 t ha-1), straw yield (16.27 t ha-1) and biological yield (25.70 t ha-1) were obtained from 1 seedling hill-1 (NS1) with the closest spacing 15 cm X 15 cm Therefore, one seedling hill-1 with 15 cm distance for plant and row to row distance could ensure maximum yield of hybrid rice line Bio-453. Introduction In Bangladesh soil and climatic conditions are favorable for rice cultivation and it is extensively cultivated throughout the year in three seasons namely Aus, Aman and Boro which covers 80% of the total cultivable area of the country (AIS, 2011). In respect of production, it ranks 4th place among the rice producing countries of the world (FAO, 2018). However, the average rice yield in Bangladesh is lower than the other rice growing countries like China, Japan, Korea (FAO, 2009). Besides the cultivable land is converting into non cultivable land around @1% every year (Quasem, 2011). In this situation hybrid rice production can be a good option to contribute to increase rice yield about 15- 20% over the modern varieties (Julfiquar et al., 2001). Bangladesh Rice Research Institute (BRRI) already released six hybrid rice varieties in Boro and T. aman, however only two rice hybrids released for T. aman season. But recently farmers are reluctant to cultivate more hybrid rice because of its higher requirements of fertilizer, irrigation etc. than the conventional rice either local or HYV which ultimately increase the cost of production. Sylhet is situated in the North-East portion of Bangladesh which is comparatively a higher rainfall area. T. aman occupying a major percentage in the cropping patterns of this area (DAE, 2012). about:blank 38 Chowdhury et al. Number of seedling hill-1 plays an important role to enable the plant to grow properly both in its aerial and underground parts by utilizing maximum radiant energy, nutrient, space and water and also could reduce seedlings cost of farmers. Proper plant spacing responsible for the plant density that can minimize the seed requirement without sacrificing productivity of hybrid rice cultivation. Profuse tillering of the hybrid rice may compensate the yield due to reduction in plant population (Srinivasulu et al., 1999). The growth, development, yield and yield components of rice are greatly influenced by plant spacing through proper utilization of solar radiation, soil and applied nutrients (Akter, 2004). When the plant densities and seedling hill-1 exceed optimum level, competition among them for light and nutrients become severe. Consequently, the growth rate slows down and the grain yield decreases. Wider spacing can produce more tillers when soil, water and nutrients are sufficiently available that produce higher yield. Keeping in view, a new advanced Hybrid rice line Bio-453 under two levels of seedling hill-1 and five levels of plant spacing were undertaken to know the effect of number of seedling hill-1 and spacing on yield and yield attributes. Materials and Methods The study was carried out at the field of Agronomy and Haor Agriculture Department of Sylhet Agricultural University, in Kharif-II (Aman) season during July to November 2013.The experiment was laid out in a split-plot design with three replications where main plot includes number of seedling hill-1 such as: 1) seedling hill-1 (NS1) and 2) seedlings hill -1 (NS2) and in sub-plot assigned plant spacing such as:i) 15 cm × 15 cm (Sp1), ii) 15 cm X 20 cm (Sp2), iii) 20 cm X 20 cm (Sp3), iv) 20 cm X 25 cm (Sp4) and v) 20 cm X 30 cm (Sp5).The size of the unit plot was 4.8 m2 Hybrid rice line Bio-453 was collected from Bioseed Research India Pvt. Ltd. Sprouted seeds were sown in the well-prepared wet nursery bed. Thirty-four days old seedling was transplanted at a depth of 3-5 cm. During transplanting 5-7 cm water depth was maintained in each plot. Different intercultural operations were done for ensuring the normal growth of the crop. The experimental field was ploughed leveled well and well decompose cow dung was applied @5 t ha-1. Dolochun lime was applied @0.75 t ha-1 to increase soil pH. The experimental area was fertilized with 68.72 kg, 10.98 kg, 41.81 kg, 14.04 kg, 1.1 kg of N, P, K, S and Zn per hectare, respectively (BRRI, 2013). One-third of urea and the entire TSP, MoP, gypsum and zinc oxide were incorporated into the soil during final land preparation. Remaining two-thirds of urea was top dressed at 40 days after transplanting (DAT) and at 55 DAT. Data were collected on yield and yield attributes. The collected data were tabulated and analyzed using computer package program R. Mean differences were adjudged by the Least Significant Difference (LSD) test at 5% level of significance. Results and Discussion Plant height Effect of number of seedling hill-1 (NS) No significant differences were observed on plant height at different DAT in variation of number ofseedlingshill-1. Effect of spacing (Sp) Plant spacing exerted significant effect on plant height at different DAT (Fig. 1). Although the maximum plant height (135.50 cm) was recorded atSp2 which was similar to Sp1 (135.12 cm) and spacing Sp4 (130.58 cm). The minimum plant height (122.74 cm) was obtained from the widest spacing Sp5. Performance of Hybrid Rice 37 Fig. 1. Effect of spacing (Sp) on plant height at different days after transplanting (DAT) (LSD = 3.67, 4.08, 5.24, 4.37, 6.18 and 7.02 at 54, 69, 84, 99, 114 and 129 DAT, respectively. Interaction effect of number of seedling hill-1 and spacing Plant height at different DAT was significantly influenced by the interaction between number of seedling hill-1 and spacing (Fig. 2). The maximum plant (143.68 cm) was recorded from NS1×Sp1 that was statistically closer to the plant height of NS1×Sp2 and NS2×Sp4 (140.90 cm and 140.18 cm). The shortest plant height was observed in treatment of NS1×Sp5 that was statistically similar to NS1×Sp4 and NS2×Sp3.The result was similar with the findings of Ninad et al. (2017), Shrirame et al. (2000) and Shah et al. (1991). Fig. 2. Interaction effect of number of seedling hill-1 and spacing on plant height at different DAT (LSD = 5.19, 5.77, 7.41, 6.19, 8.74 and 9.92 at 54, 69, 84, 99, 114 and 129 DAT, respectively). Number of tiller hill-1 at every 15-day intervals Effect of number of seedlings hill-1 38 Chowdhury et al. Number of seedling hill-1 had significant effect on number of tiller hill-1at earlier stage but no significant effect on later stage (Fig. 3). The higher number of tiller hill-1 (8.22) was obtained from NS2at 84 DAT and the lower number of tiller hill-1 (5.81) was obtained from NS1 at 54 DAT. Fig. 3. Effect of number of seedling hill-1 (NS) on number of tiller hill-1 at different DAT (LSD = 0.66, 0.13, 0.98, 1.90, 2.13 and 1.97 at 54, 69, 84, 99, 114 and 129 DAT, respectively). Effect of spacing There was significant effect of plant spacing on number of tiller hill -1 at different DAT except 54 DAT (Fig. 4). The maximum number of tiller hill- 1(11.87) was obtained from the spacing of Sp5 at 99 DAT. The minimum number (7.43) was found from the spacing of Sp1at 54 DAT which was statistically similar to the number of tiller hill-1 7.46 and 8.23 with the spacing of Sp2 and Sp3, respectively. Fig. 4. Effect of spacing on number of tiller hill-1 at different DAT (LSD = 0.84, 1.37, 1.17, 1.20, 1.60 and 1.35 at 54, 69, 84, 99, 114 and 129 DAT, respectively). Interaction effect of number of seedling hill-1 and spacing Performance of Hybrid Rice 37 Number of tiller hill-1 at 114 DAT was significantly influenced by interaction between number of seedling hill-1 and spacing (Fig. 5). The highest number of tiller hill-1 (13.27) was found from NS2×Sp5 at 99 DAT. The lowest number (5.13) was obtained from NS1×Sp1 at 54 DAT. Fig.5 Interaction effect of number of seedling hill-1 and spacing on number of tiller hill-1at different DAT (LSD = 1.19, 1.93, 1.66, 1.70, 2.26 and 1.91 at 54, 69, 84, 99, 114 and 129 DAT, respectively). Phenology, yield components and yield Effect of number of seedling hill-1 Number of seedling hill-1 had no significant effect on days to 50% panicle initiation, days to maturity, plant height at harvest (Table 1). Shrirame et al. (2000) observed similar results. Gupta (1996) also found that transplanting of one seedling hill-1 significantly increased plant height. This observation was also supported by Nayak et al. (2003) who stated that plant height recorded significantly more with 1 seedling hill-1 than the 2 seedlings hill-1. Similar result was found in case of non-effective tiller hill-1, panicle length, grains panicle-1, Weight of 1000-grain, grain yield, straw yield, biological yield. Rajarathinam (1999) similarly stated that the straw yield of hybrid rice was not changed significantly due to planting of single or double seedlings hill-1. Number of total tiller hill-1 and effective tiller hill-1 were significantly influenced by number of seedling hill-1 (Table 1). The higher number of total tiller hill-1 (12.13) was found in 2 seedlings hill-1 (NS2) and the lower one (10.91) with 1 seedling hill-1 (NS1). Alam (2006) reported similarly that highest number of effective tillers was obtained from 2 seedlings hill-1. Number of seedling hill-1 had no significant effect on harvest index (Table 1). Table 1. Phenology and yield components of hybrid rice line Bio-453 as influenced by number of seedlings hill-1 38 Chowdhury et al. No. of Seedling hill-1 (NS) Days to 50% flowering Days to maturity Plant height (cm) Total tiller hill-1 (no.) Effective tiller hill- 1 (no.) Non- effective tiller hill- 1 (no.) Panicle length (cm) NS1 105 137 131.69 10.91 b 8.55 b 2.36 24.53 NS2 105 130 131.41 12.13 a 9.35 a 2.77 24.35 LSD (0.05) NS NS NS 1.17 0.84 NS NS Cont’d No. of seedling hill- 1 Grain panicle-1 (no.) 1000-grain weight (g) Grain yield (t ha-1) Straw yield (t ha-1) Biological yield (t ha-1) Harvest index (%) NS1 81.24 27.15 8.38 13.17 21. 72 38.69 NS2 80.15 26.77 8.02 13.06 21.08 38.08 LSD (0.05) NS NS NS NS NS NS Note: NS1 = 1 seedling hill -1; NS2 = 2 seedlings hill -1; NS = Non-significant; * indicate 5% level of significance. Effect of spacing Days to maturity, plant height, panicle length, grain panicle-1, 1000 grain weight and harvest index was not significantly affected by plant spacing (Table 2). Days to 50% flowering Plant spacing had significant effect on days to 50% flowering (Table 2). Maximum days (107) required for 50% flowering at the spacing of Sp4 and Sp5 whereas statistically minimum days (103) required at the spacing of Sp1, Sp2 and Sp3. Total tiller hill-1 Plant spacing had significant effect on number of total tiller hill-1 (Table 2). The maximum number of total tiller hill-1 (13.61) was found in the wider Sp5 which was statistically similar to spacing Sp4. The lowest number (9.50) was observed in the closest spacing Sp1. The plants grown in Sp5 possibly experienced more light, space, air and nutrient facilities which stimulated positively towards tiller formation than the closer spacing. Effective tillers hill-1 The number of effective tillers hill-1 was significantly influenced by spacing (Table 2). The maximum number of effective tillers hill-1 (10.88) was obtained from Sp5 which was statistically similar to theSp4 (10.61). The lowest one (7.43) was obtained from Sp2 which was statistically similar with Sp2 and Sp3 (7.61 and 8.10, respectively). The result showed that Sp5 had the greatest opportunity to produce more number of effective tillers hill-1 because it gets enough space, nutrients, light and air which played great role in producing more effective tillers hill-1. Baloch et al. (2002) reported wider spaced plant produced more effective tillers in rice than closer one. Non-effective tillers hill-1 The number of non-effective tillers hill-1 was significantly influenced by spacing (Table 2). The highest number of non-effective tillers hill-1 (2.94) was found in Sp3 which Performance of Hybrid Rice 37 was statistically closer to the number of non-effective tillers hill-1of 2.72 and 2.82 with the spacing Sp2 and Sp5, respectively. The lowest number (2.04) was found in the spacing Sp1 which was statistically similar to the Sp4 (2.39). Grain yield Plant spacing had significant effect on grain yield (Table 2). The maximum grain yield (8.93 t ha-1) was obtained from Sp1 which was statistically similar with Sp2 and Sp3 (8.63 and 8.45 t ha -1). The result was similar to Ninad et al. (2017) and Chandra et al. (1997) who recorded that the closer spacing 15 cm x 15 cm gave 10-12% higher yield than the other spacing. The lowest yield (7.28 tha-1) was obtained from the spacing 20 cm x 30 cm (Sp5) which was also statistically similar to the grain yield of 7.66 t ha-1 obtained from the spacing 20 cm x 25 cm (Sp4). The results revealed that closest spacing gives higher yield performance whereas wider spacing gave lower yield. This might be due to the fact that closest spacing had higher plant population (i.e. hill unit-1 area) than the corresponding wider spacing in spite of higher number of effective tillers hill-1, filled grains panicle-1 and 1000-grain weight. The result corroborates with the findings of other few research findings that closer spacing had higher grain yield than the other spacing (Azad et al., 1995; Patel, 1999; Obulamma et al., 2002). Straw yield Straw yield was significantly influenced by spacing (Table 2). The maximum straw yield (14.47 t ha-1) was produced from the closest spacing 15 cm x 15 cm (Sp1) which was statistically closer to the straw yield (14.17 t ha -1) obtained from the spacing 15 cm x 20 cm (Sp2). The moderate straw yield (13.02 t ha -1) was recorded from the spacing 20 cm x 20 cm (Sp3) which was statistically similar to the straw yield (12.57 t ha-1) obtained from the spacing 20 cm x 25 cm (Sp4). The minimum yield (11.35 t ha -1) was produced from the widest spacing of 20 cm x 30 cm (Sp5). The results showed that straw yield increased with closer spacing and decreased with wider spacing. Biological yield Plant spacing exerted significant effect on biological yield (Table 2). The highest biological yield (23.40 t ha-1) was obtained from the closest spacing Sp1 which was statistically similar to the biological yield Sp2 (22.85 t ha -1). The lowest biological yield (18.63 t ha-1) was obtained from the widest spacing Sp5. The result showed that closer spacing provided the highest biological yield. It might be due to the fact that closer spacing had more population densities which added more biomass that was accumulated before flowering and translocated to the grains during grain filling. Table 2. Phenology and yield components of hybrid rice line Bio-453 by spacing 38 Chowdhury et al. Plant Spacing (Sp) Days to 50% flowering Days to maturity Plant height (cm) Total tiller hill-1 (no.) Effective tiller hill-1 (no.) Non- effective tiller hill-1 (no.) Panicle length (cm) Sp1 103 b 137 133.78 9.50 d 7.44 c 2.04 c 24.76 Sp2 104b 137 134.77 10.45 c 7.61 c 2.82 ab 24.53 Sp3 104 b 137 130.05 11.05 c 8.22 c 2.94 a 24.21 Sp4 107 a 137 131.55 12.50 b 9.72 b 2.39 bc 24.47 Sp5 107 a 137.67 127.61 14.11 a 11.78 a 2.72 ab 24.22 (Continued) Plant Spacing Grain panicle-1 (no.) 1000- grain weight (g) Grain yield (t ha-1) Straw yield (t ha-1) Biological yield (t ha-1) Harvest index (%) Sp1 81.55 26.93 8.93 a 14.47 a 23.40 a 38.33 Sp2 79.61 26.03 8.68 a 14.17 ab 22.85 a 37.93 Sp3 79.16 26.93 8.45 a 12.57 c 21.01 b 40.20 Sp4 83.66 27.68 7.67 b 13.39 bc 21.06 b 36.35 Sp5 79.50 27.21 7.28 b 11.35 d 18.63 c 39.13 Note: Sp1 = 15 cm x 15 cm; Sp2 = 15 cm x 20 cm; Sp3 = 20 cm x 20 cm; Sp4 = 20 cm x 25 cm; Sp5 = 20 cm x 30 cm Interaction effect of number of seedling hill-1 and spacing Days to 50% flowering Days to 50% flowering, days to maturity, plant height, total tillers hill-1, panicle length, grains panicle-1, 1000-grain weight and harvest index was not significantly influenced by the interaction between number of seedling hill-1 and spacing (Table 3). Effective tillers hill-1 Number of effective tillers hill-1 was significantly affected by interaction between number of seedling hill-1 and spacing (Table 3). The highest number of effective tillers hill-1 (12.22) from 2 seedlings hill-1 (NS2) with 20 cm x 30 cm spacing (Sp5) which was statistically similar to1 seedling hill-1 (NS1) with 20 cm x 30 cm spacing (Sp5). The number of effective tillers hill -1 of 7.63 and 7.88 recorded from 2 seedlings hill-1 (NS2) with the spacing 15 cm x 15 cm (Sp1) and 15 cm x 20 cm (Sp2), respectively was statistically similar. The lowest number (7.22) was recorded from 1 seedling hill-1 (NS1) with the spacing of 15 cm x 15 cm (Sp1) that was statistically similar to 1 seedling hill-1 (NS1) with 15 cm× x 20 cm (Sp2) and 20 cm x 20 cm (Sp3) spacing, respectively. Non-effective tillers hill-1 Performance of Hybrid Rice 37 There was significant effect by the interaction between number of seedling hill-1 and spacing on number of non-effective tillers hill-1 (Table 3). The maximum number of non-effective tillers hill-1 (3.55) was found in NS2× Sp2which was significantly closer to NS1Sp3 and NS1Sp4, respectively. The minimum number (1.66) was obtained from NS1Sp1 which was as at par to (NS1Sp2) and (NS1Sp5), respectively. Grain yield Significant influence by interaction between number of seedling hill -1 and spacing on grain yield was found (Table 3). Maximum grain yield (9.43 t ha -1) was obtained from NS1×Sp1 which was statistically similar to NS1Sp2 and NS1Sp3 (9.26 and 8.86 t ha -1 respectively). The result corroborates with the findings of (Strivastava and Tripathi, 1998) that 1 seedling hill-1 in combination with the spacing 15 cm x 15 cm (Sp1) produced the highest grain yield in hybrid rice. Minimum grain yield (7.0 t ha -1) was obtained from (NS1Sp5) which was significantly similar to the grain yield (7.36 t ha-1) from NS1Sp4. The results revealed that the combination of single seedling hill -1 with closer spacing had higher yield performance whereas the combination of single seedling hill-1 with wider spacing had lower yield performance. Straw yield The interaction between number of seedling hill -1 and spacing exerted significant effect on straw yield (Table 3). The maximum straw yield (16.27 t ha-1) was produced from NS1× Sp1 that was statistically similar to the straw yield (14.83 t ha-1) at NS1Sp2. The lowest straw yield (10.43 t ha -1) was produced from NS1×Sp5 which was similar to NS1× Sp3 (11.77 t ha -1). The straw yield (12.53 t ha-1) produced at 1 seedling hill-1 (NS1) with the spacing of 20 cm x 25 cm (Sp4) statistically similar to the straw yield of 12.67 t ha - 1, 12.60 t ha-1 and 12.27 t ha-1 recorded from 2 seedlings hill-1 (NS2) with the spacing of 15 cm x 15 cm (Sp1), 20 cm x 25 cm (Sp4) and 20 cm x 30 cm (Sp5), respectively. Biological yield Biological yield was significantly influenced by seedling hill -1 and spacing (Table 3). Maximum biological yield (25.70 t ha -1) was found in (NS1×Sp1) which was statistically similar with NS1×Sp2 (24.10 t ha -1). Minimum biological yield (17.43 t ha-1) recorded from 1 seedling hill-1 (NS1) with 20 cm x 30 cm spacing (Sp5), which was significantly different from the others. Table 3. Phenology and yield components of hybrid rice line Bio-453 by interaction effect of number of seedling hill-1 (NS) and spacing (Sp) Interaction of NSSp Days to 50% flowering Days to maturity Plant height (cm) Total tillers hill-1 (no.) Effective tillers hill-1 (no.) Non-effective tillers hill-1 (no.) Panicle length (cm) NS1 x Sp1 103 137 141.00 8.89 7.22 1.66 d 25.04 NS1 x Sp2 106 138 140.88 9.44 7.36 2.05 cd 24.77 NS1 x Sp3 105 137 132.78 10.33 7.23 3.12 ab 24.05 NS1 x Sp4 106 134 123.11 12.44 9.55 2.88 ab 24.75 NS1 x Sp5 106 137 120.67 13.44 11.33 2.10 cd 24.02 NS2 x Sp1 104 136 126.56 10.11 7.63 2.44 bcd 24.48 NS2 x Sp2 103 136 128.65 11.44 7.88 3.55 a 24.27 NS2 x Sp3 102 137 127.33 11.78 9.11 2.66 bc 24.36 NS2 x Sp4 107 138 139.98 12.56 9.89 2.67 bc 24.18 NS2 x Sp5 108.0 138 134.56 14.78 12.22 2.56 bc 24.43 (Continued) 38 Chowdhury et al. Interaction of NSSp Grain panicle-1 (no.) 1000-grain weight (g) Grain yield (t ha-1) Straw yield (t ha-1) Biological yield (t ha-1) Harvest index (%) NS1 x Sp1 84.22 27.43 9.43 a 16.27 a 25.70 a 36.66 NS1 x Sp2 83.78 26.89 9.26 ab 14.83 ab 24.10 ab 38.33 NS1 x Sp3 76.77 26.60 8.86 abc 12.53 de 21.40 cd 41.43 NS1 x Sp4 80.11 26.83 7.36 ef 11.77 ef 19.96 d 36.90 NS1 x Sp5 77.28 26.90 7.00 f 10.43 f 17.43 e 40.13 NS2 x Sp1 83.10 27.93 8.43 bcd 12.67 cde 21.10 cd 40.00 NS2 x Sp2 75.44 26.36 8.10 cde 13.50 bcd 21.60 cd 37.53 NS2 x Sp3 81.55 27.27 8.03 cde 12.60 de 20.63 cd 38.96 NS2 x Sp4 82.99 27.03 7.96 cdef 14.27 bc 22.23 bc 35.80 NS2 x Sp5 80.72 27.20 7.56 def 12.27 de 19.83 d 38.13 Note: NS= Number of seedling; Sp= Spacing. Conclusion From the experimental findings it is clear that hybrid rice line Bio-453 planted with 1 seedling hill-1 along with 15 cm x 15 cm spacing produced maximum grain yield (9.43 t ha-1) while combination of 2 seedlings hill-1 along with 20 cm x 30 cm spacing contributed lower yield (7.56 t ha-1). Consequently, hybrid rice line Bio-453 with the combination of 1 seedling hill-1 with 15 cm x 15 cm spacing to be the best possible combination for achieving higher grain yield per unit area. References AIS. 2011. Krishi Dairy, Agril. Inform. Ser. Kamarbari, Farmgate, Dhaka, Bangladesh. Akter, F.M.F. 2004. Effect of plant spacing and nitrogen level on the performance of transplant aman rice. MS Thesis, Dept. of Agron., Bangladesh Agril. Univ., Mymensingh, Bangladesh. Alam, F. 2006. Effect of spacing, number of seedlings hill-1 and fertilizer management on the performance of Boro rice cv. BRRI dhan29. Thesis, Dept. Agron., Bangladesh Agril. Univ., Mymensingh, Bangladesh. 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