Effect of Boron Levels on Growth and Yield of Vegetable Crops in Bangladesh

62 Hasan et al. Int. J. Biosci. 2025 RESEARCH PAPER RESEARCH PAPER RESEARCH PAPER RESEARCH PAPER OPEN ACCESS OPEN ACCESSOPEN ACCESS OPEN ACCESS Effect of Boron Levels on Growth and Yield of Vegetable Crops in Bangladesh B. M. Mahmudul Hasan *1 , Md. Nurul Alam 1 , Md. Hanjala Pipil 1 , Marufa Yeasmin 2 , C.M Aditta Alam Protham 2 , Md Rezoanul Islam 2 1 Department of Biochemistry and Molecular Biology, Trust University, Barishal, Bangladesh 1Department of Crop Science and Engineering, University of Rajshahi, Bangladesh 2Department of Biochemistry and Molecular Biology, Trust University, Barishal, Bangladesh 2Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalganj, Bangladesh Key words: Boron, Vegetable crops , T oxicity, Environment http://dx.doi.org/10.12692/ijb/26.1.62 - 73 Article published on January 04, 2025 Abstract The experiments were conducted to investigate the effect of B levels on growth and yield of cabbage, cauliflower, carrot, potato and radish. The soil was medium fertility with low B content. The experiments were laid out in RCBD with 3 replications. There were seven levels of B viz. 0, 1, 2, 3, 4, 5 & 6 kg /ha. The B was used as boric acid. The results revealed that the application of B in deferent levels significantly influenced the growth and yield of vegetable crops. The yield of cabbage, cauliflower, potato and radish responded significantly to added B up to 3 kg/ha. The yield advantages due to B application are cabbage (68.32 %), cauliflower (70.84 %), potato (47.74 %) and radish (49.07 %) over control. Whereas, application of 2 kg B/ha produced the maximum root yield of carrot (40.47 %) yield over control also. The yield of vegetables was reduced without appropriate rate of B application. It is concluded that the suitable range of B application is 2-3 kg/ha for maximum vegetable crop production in upland soils of Bangladesh. The rate of 2 kg B/ha is applicable for relatively low biomass yielded vegetable crops and 3 kg B/ha for higher yielded vegetable crops, respectively. Interestingly, it can be also stated that the B application 5 kg/ha or above will be harmful and stunted or may be toxic their vegetative growth of vegetables. * Corresponding Author: B.M. Mahmudul Hasan  jewelgono @gmail.com International Journal of Biosciences | IJB | ISSN: 2220-6655 (Print), 2222-5234 (Online) http://www.innspub.net Vol. 26, No. 1, p. 62-73, 2025 63 Hasan et al. Int. J. Biosci. 2025 Introduction Boron is an essential micronutrient requirement for normal growth and development. It is a very sensitive element and plants differ widely in their requirements but the ranges of deficiency and toxicity are narrow. The B concentration in soils varied widely with soil types and environment. The B requirements are common on upland crops in humid regions and also in calcareous soil. Boron deficiencies are widespread in humid regions by leaching losses (Thoeh et al., 1993). It is wide spread and often incipient that B deficiency seems to exist in Bangladesh soils (Protch and Islam, 1984). Zinc and Boron normally becomes less available to plants with increasing soil pH. When Ca availability is high, there is a greater requirement of B for plant growth and yield (Tisdale et al., 1995). Many researchers observed that B application increased growth and yield of upland crops likewheat, pulses, oil seeds, potato, carrot, radish and papaya. Boron @ 3.0 kg/ha produced the highest grain yield of wheat, which was statistically similar to that produced by 2.0 kg B/ ha (Hafiz Akter et al., 2001). Pregno and Arour (1992) also reported that the highest potato tuber yield was found when 2 kg B/ ha was applied to the soil followed by 4 kg B / ha. The highest yield of carrot was obtained when B was applied with a basal NPK (Nelyubora et al., 1972). Maurya and Singh (1985) found that borax 10 kg/ha gave the highest radish yield increase viz. 41% over the control and the best protein and ascorbic acid content. Khanam et al. (2000) observed that the application of Mg and B is necessary for improving yield potentialities of chickpea and lentil at BAU farm soil of Bangladesh. Application of different levels of B influenced the growth and yield of crops reported by Maurya and Singh (1985) in carrot, Quaggio and Ranos (1986) in potato, Efkar et al. (1995) in potato, Porter et al. (1986) in potato, Ali et al. (2001) in papaya and Hafiz Akter et al. (2001) in wheat. The requirements of B fertilizer in vegetables are generally more than other corps. Rasp (1985) mentioned that the effect of added trace elements in 12 years of crop rotation in which potatoes and cereals were grown in alternate years. It was found that only B tended to increase potato yield. High Ganges River Floodplain soil (AEZ-11) is one of the most important calcareous soils of Bangladesh. The soils have large content of CaCO 3 , as well as high concentration of available Ca ++ present in that soil. The pH is generally ranging from 7.0-8.5 but in most of the upland soils ranges from 7.5-8.5. In fact, information regarding B requirements for vegetable should be meager in Calcareous and Baind soils of Bangladesh. Therefore, an attempt was made to study the effect of B levels on growth and yield of vegetable crops in Bangladesh. Materials and methods The experiments were conducted in calcareous soil during the period from October 2009 to February 2010 and also in Barind soil during the period from October 2010 to March 2011 to determine the effect of B levels on growth and yield of cabbage, cauliflower & carrot and potato & radish, respectively. The soil samples (0-15 cm) were collected and analyzed soil texture by Hydrometer method and other parameters by Hunter (1984) method. The experimental calcareous soil was low in fertility having pH 7.8 and silty clay loam texture, organic matter 1.12%, total N 0.07%, available P 19.6 mg/kg, exchangeable K 0.28 me/100g, available S 1.9 mg/kg, exchangeable Ca 17.66 me/100g, exchangeable Mg 0.79 me/100g, available Fe 67.6 mg/kg, available Mn 26.8 mg/kg, available Cu 1.68 mg/kg, available Zn 0.68 mg/kg and available B 0.22 mg/kg and also Barind soil was low in fertility having pH 5.6 and silt loam texture, organic matter 0.96%, total N 0.07%, available P 149.6 mg/kg, exchangeable K 0.23 me/100g, available S 2.3 mg/kg, exchangeable Ca 6.35 me/100g, exchangeable Mg 0.49 me/100g, available Fe 65.6 mg/kg, available Mn 32.3 mg/kg, available Cu 1.84 mg/kg, available Zn 0.48 mg/kg and available B 0.18 mg/kg. There were 7 levels of B viz. 0, 1, 2, 3, 4, 5 and 6 kg/ha in the treatments as boric acid. The experiment was laid out in a RCBD with three replications. Other nutrients like N, P, K, S and Zn were applied at the rate of 150-50-100-20-3 kg/ha as basal dose during final land preparation and Mo was used as spray. 64 Hasan et al. Int. J. Biosci. 2025 Urea, TSP, MP, gypsum, zinc sulphate and ammonium molybdate were applied as the sources of N, P, K, S, Zn and Mo respectively. All fertilizers except urea were applied during land preparation and Mo was applied at 45 days after planting/sowing. Urea was used in three splits i.e. at final land preparation, 30 and 55 days after planting (DAP). There was no organic used in the field because organic matter has large content of boron. The size of each plot was 5m×5m, spacing 50cm×50cm for cabbage and cauliflower, spacing 25cm×20cm for Potato and 18cm×15cm for radish. The intercultural operation, weeding, pest management and irrigation were done as and when required. Data were recorded in randomly from 10 plants per plot. After collection of data, it was tabulated in proper form and subjected to the statistical analysis with the help of computer package MSTAT-C and means were separated by DMRT at 5% LSD values (Russell, 1996). Results and discussion Effect of boron levels on growth and yield of cabbage in calcareous soil Plant height Application of different levels of B showed significant effects on plant height at different days after transplanting of cabbage. At 30 DAT, the maximum plant height (23.39 cm) was recorded in treatment B 3 and the second but statistically similar in B 4 . At both 45 and 60 DAT, the maximum plant heights were also found in B 3 . Table 1. Effect of B levels on plant height and plant spread of cabbage. Treatments Plant height (cm) Plant spread (cm) 30 DAT 45 DAT 60 DAT 30 DAT 45 DAT 60 DAT B 0 = Control 18.14 25.19 27.50 28.58 39.45 47.66 B 1 = 1 kg B/ha 19.47 28.33 32.22 32.56 51.54 57.52 B 2 = 2 kg B/ha 21.24 32.01 37.43 3 6.00 57.35 61.74 B 3 = 3 kg B/ha 23.39 33.23 39.55 36.17 63.80 66.37 B 4 = 4 kg B/ha 23.06 30.46 36.37 35.20 59.61 65.45 B 5 = 5 kg B/ha 19.32 26.60 32.80 32.36 53.45 59.02 B 6 = 6 kg B/ha 18.11 24.52 29.52 30.43 48.26 57.70 LSD at 5% 0.83 1.17 2. 11 1.87 2.68 3.20 CV (%) 3.68 7.94 5.89 6.46 5.92 8.18 In a column, figure(s) having common letter(s) do not differ significantly by DMRT at 5% level, DAT = Days after transplant. The lowest plant heights were observed in B 6 and B 0 (control)). Alam (2007) suggested that the growth and yield contributing parameters of cabbage increased up to 4.0 kg B/ha and decreased gradually with the increases of B levels (>4.0 kg B/ha). Porter et al. (1986) showed that plants were stunted and yields reduced at application of grater than 4.5 kg B/ ha. Pregno and Arour (1992) mentioned that the highest tuber yield was found when 2 kg B/ha was applied and followed by 4 kg B/ha. The plant height was not increased by low rates of B but was reduced by 8 and 12 kg B/ha compared with no B. Plant spread Statistically significant difference was observed in plant spread affected by B levels in cabbage. The plant spread at different stages of growth (at 30, 45, and 60 DAT) was ranged from 28.58-36.17 cm, 39.45-63.80 cm and 47.66-66.37 cm respectively (Table 1). At all the growth stages (30, 45 and 60 DAT) the widest canopy spreads were recorded in the plot treated with 3 kg B/ha. On the other hand, the lowest plant spread was observed in B 0 and B 6 at all DAT. Alam (2007) reported that plant spread was significantly influenced by applied boron levels and maximum value was found for 3.0 kg B/ha. 65 Hasan et al. Int. J. Biosci. 2025 Number of leaves per plant Application of different doses of B exerted a significant influence on the number of leaves per plant in cabbage. The number of leaves increased with increasing B levels up to 4 kg B/ha. At all DAT, the highest number of leaves was found at 4 kg B/ha, which was statistically similar with 3 kg B/ha. The lowest number of leaves was found in the plot treated with control and 6 kg B/ha. Alam (2007) reported that leaf number was significantly influenced by B levels and maximum leaf number was found for 3.0 kg B/ha. Table 2. Effect of B levels on number and length of leaves of cabbage. Treatments Number of lea ves per plant Length of largest leaf (cm) 30 DAT 45 DAT 60 DAT 30 DAT 45 DAT 60 DAT B 0 = Control 10.86 13.92 15.31 17.18 22.33 27.38 B 1 = 1 kg B/ha 12.83 18.11 19.16 19.44 26.42 32.51 B 2 = 2 kg B/ha 13.75 17.38 18.36 22.13 27.90 33.48 B 3 = 3 k g B/ha 13.93 18.20 18.81 24.39 30.37 35.43 B 4 = 4 kg B/ha 14.17 18.22 19.34 25.28 31.78 35.72 B 5 = 5 kg B/ha 13.50 17.50 19.03 24.40 30.44 32.56 B 6 = 6 kg B/ha 11.83 17.33 18.17 21.90 29.61 30.83 LSD at 5% 1.13 1.22 1.30 1.27 1.44 1.36 CV (%) 3. 65 7.50 2.56 3.42 3.94 6.12 In a column, figure(s) having common letter(s) do not differ significantly by DMRT at 5% level. Length of largest leaf The length of leaf influenced by B levels was found to be significant in growth period (Table 2). The largest leaf was recorded in the plot treated with B 4 and followed by B 3 but both are statistically similar in all stages. Ahmmad et al. (2009) showed that the length of largest leaf of cauliflower was significantly increased by the application of B at 3 kg/ha with Zn at 3 kg/ha. The results are in agreement with the findings of Alam (2007). Table 3. Effect of B levels on leaf breadth and stem length of cabbage. Treatments Breadth of largest leaf (cm) Length of stem (cm) 30 DAT 45 DAT 60 DAT 30 DAT 45 DAT 60 DAT B 0 = Control 10.13 17.73 19.65 4.37 5.09 6.37 B 1 = 1 kg B/ha 11.48 19.28 21.36 4.40 6.57 6.65 B 2 = 2 kg B/ha 12.03 19.84 22.16 4.48 6.93 6.21 B 3 = 3 kg B/ha 12.57 21.35 23.30 4.96 7.57 6.93 B 4 = 4 kg B/ha 11.72 20.61 23.10 5.35 7.90 7 .04 B 5 = 5 kg B/ha 11.36 20.05 22.22 4.50 6.11 6.23 B 6 = 6 kg B/ha 10.50 18.46 20.52 4.32 6.30 6.63 LSD at 5% 0.51 0.93 0.76 0.55 0.88 0.67 CV (%) 5.24 2.59 2.87 4.90 3.28 4.39 In a column, figure(s) having common letter(s) do not differ significantly by DMRT at 5% level. Breadth of largest leaf Application of different levels of B caused significant effects on the breadth of leaves at different DAT (Table 3). The highest breadth of leaf was found by B 3 and the second highest in B 4 , and the minimum in control. The results are in partial agreement with Alam (2007) in cabbage, Ahmmad et al. (2009) in cauliflower and Ahmmad (2009) in cabbage. Length of stem Significant effects of micronutrient combination are observed on the length of cabbage. The results on length of stem influenced by B levels have been presented in Table 3. The stem length increases with increases of B levels up to 4 kg/ha and decreases gradually. The maximum stem length was found in B4 and the minimum in control in growth stages. 66 Hasan et al. Int. J. Biosci. 2025 Table 4. Effect of B levels on growth and yield of cabbage at harvest. Treatments Days to head formation Fresh weight of plant (g) Diameter of head (cm) Thickness of head (cm) Marketable head weight (g) Marketable head yield (t/ha) % Yield increa se over control B 0 = Control 59.30 1052 12.83 9.73 908 28.11 - B 1 = 1 kg B/ha 54.75 1317 15.37 11.30 1123 38.60 37.32 B 2 = 2 kg B/ha 52.22 1420 17.90 11.70 1254 43.19 53.65 B 3 = 3 kg B/ha 49.50 1680 20.45 12.80 1465 47.33 68.37 B 4 = 4 kg B/ha 48.16 1737 19.83 12.43 1395 46.95 67.02 B 5 = 5 kg B/ha 48.36 1473 16.80 11.15 1163 42.12 49.84 B 6 = 6 kg B/ha 49.65 1290 14.03 10.93 1016 35.87 27.61 LSD at 5% 2.06 112 1.02 0.43 137 2.11 - CV (%) 3.54 10.56 2.56 3.85 8.33 6.19 - In a column, figure(s) having common letter(s) do not differ significantly by DMRT at 5% level. Days to head formation The number of days required for head formation was significantly influenced by the treatments. The number of days required for head formation ranged from 48.16 to 59.30 (Table 4). The maximum number of days required for head formation (59.30 days) was observed in control plot. The minimum days to started the head was (48.16 days) in B 4 followed by B 5 . It is indicated that B is required for early head formation or leaf folding of cabbage. The results are strongly supported by Alam (2006). Fresh weight of plant Fresh weight of plant along with root was found to be affected by B levels. The fresh weight of plant was ranges between 1052 g to 1737 g (Table 4). The maximum fresh weight of plant was observed in the plot treated with B 3 followed by B 4 but both are statically similar. However the minimum fresh weight of plant was found in control. The findings are in agreement with Alam (2007). Diameter of head The head diameter of cabbage significantly affected due to the addition of increasing rates of boron fertilizer (Table 4). The head diameter ranged from 12.83 to 20.45 cm. The maximum head diameter (20.45 cm) was found in B 3 but B 3 is similar with B 4 (19.83 cm). Application of above 3 kg B/ha decreased the head diameter of cabbage. The lowest head diameter was also found in control (B 0 ). Alam (2007) reported that the maximum head diameter was observed at 4 kg B/ha followed by 3 kg B/ha but both are statically similar. Table 5. Effect of B levels on growth and yield components of cauliflower. Treatments Plant spread (cm) Plant height (cm) Largest leaf length (cm) Largest leaf breadth (cm) No. of leaves /plant B 0 = Control 52.40 42.23 40.43 18.70 16.93 B 1 = 1 kg B/ha 58.76 47.63 44.30 20.93 17.06 B 2 = 2 kg B/ha 61.66 49.40 46.23 22.33 19.36 B 3 = 3 kg B/ha 65.63 52.23 48.83 23.70 19.73 B 4 = 4 kg B/ha 64.53 53.46 49.13 22.93 20.80 B 5 = 5 kg B/ha 59.86 49.63 45.30 20.93 19.06 B 6 = 6 kg B/ha 57.56 47.40 42.23 19.33 18.36 LSD at 5% 3.05 3.11 2.83 1.96 2.06 CV (%) 7.18 3.12 5.43 5.53 4.84 In a column, figures having same letter(s) do not differ significantly by DMRT at the 5 % level. 67 Hasan et al. Int. J. Biosci. 2025 Thickness of head The thickness of head was influenced significantly by the application of B levels (Table 4). The head thickness ranged from 9.73 to 12.80 cm. The highest head thickness (12.80 cm) was recorded in B 3 but B 3 and B 4 are statistically similar. The lowest head thickness was also found in control (B 0 ). The head thickness increased gradually up to 3 kg B/ha and above this level, it was decreased gradually. The results are partially supported by Alam (2007). Table 6. Effect of B levels on growth and yield components of cauliflower. Treatments Wt. of l eaves (g)/plant Wt. of curd (g)/plant Diameter of curd (cm) Height of curd (cm) Gross yield (t/ha) Curd yield (t/ha) % Yield increase over control B 0 = Control 328.33 617.83 15.66 12.83 46.47 22.36 - B 1 = 1 kg B/ha 474.38 721.43 17.43 14.60 56.73 29. 80 33.27 B 2 = 2 kg B/ha 542.73 888.53 18.86 15.06 63.43 35.40 58.31 B 3 = 3 kg B/ha 619.51 965.53 21.23 17.05 67.50 38.20 70.84 B 4 = 4 kg B/ha 577.53 894.30 20.46 16.73 65.46 37.16 66.18 B 5 = 5 kg B/ha 482.36 686.85 19.90 15.39 58.43 32.66 46.04 B 6 = 6 kg B/ha 395.96 512.56 17.76 13.63 50.53 28.34 26.74 LSD at 5% 72.29 55.70 1.63 0.88 3.83 1.73 - CV (%) 8.13 6.20 5.46 4.36 8.05 6.11 - In a column, figures having same letter(s) do not differ significantly by DMRT at the 5 % level. Head weight The head weight was influenced significantly due to the effects of boron levels (Table 4). The head weight ranged from 908 to1465 g. The highest head weight (1465 g) was obtained by the application of B 3 and the second highest in B 4 (1395 g) followed by B 2 (1254 g) but they are statistically similar. The lowest head weight of cabbage was found control plot. Application of above 3 kg B/ha gradually decreased the head weight of cabbage. Similar type of results was found by Alam (2007). He stated that the highest head weight was obtained by the application of 4 kg B/ha, followed by 3 kg B/ha but they are statistically similar. Table 7. Effect of B levels on growth and yield components of carrot. Treatments Plant height (cm) No. of leaves / plant Wt. of shoot (g) Length of root (cm) Diameter of root (cm) Wt. of root (g) B 0 = Control 45.43 7.23 55.76 15.26 3.23 54.16 B 1 = 1 kg B/ha 49.23 7.86 58.26 17.70 3.96 62.66 B 2 = 2 kg B/ha 50.53 7.63 75.27 18.26 4.64 67.63 B 3 = 3 kg B/ha 51.46 8.83 75.83 19.10 4.85 68.30 B 4 = 4 kg B/ha 52.13 8.96 74.93 19.46 3.83 67.56 B 5 = 5 kg B/ha 48.23 8.15 63.76 16.30 3.70 59.30 B 6 = 6 kg B/ha 46.43 8.03 58.33 15.90 3.48 57.33 LSD at 5% 1.78 1.27 3.25 1.19 0.51 4.38 CV (%) 4.93 5.55 7.13 6.62 3.24 6.15 In a column, figures having same letter(s) do not differ significantly by DMRT at the 5% level. Marketable head yield Marketable head yield (t/ha) were frond to be significantly influenced by the application of B levels. The head yield ranged from 28.11 to 47.33 (t/ha). The maximum yield (47.33 t/ha) was recorded in the treatment B 3 and it is similar with B 4 (46.95 t/ha), while the minimum yield (28.11 t/ha) was observed in T 1 (control). The head yield was gradually increased with the increase of B levels up to 3 kg/ha and then decreases. Application of 1, 2 and 3 kg B/ha increased 68 Hasan et al. Int. J. Biosci. 2025 the head yield by 37.32, 53.65 and 68.37 % respectively and maximum at 3 kg B/ha. The requirements of B fertilizer in vegetables are generally more than other corps. Rasp (1985) mentioned that the effect of added trace elements in 12 years of crop rotation in which potatoes and cereals were grown in alternate years. It was found that only B tended to increase potato yield. Porter et al. (1986) reported that the band application of B in a complete fertilizer was the most efficient technique and the tuber yield was not affected by application of less than 2.2 kg B/ha. They also showed that plants were stunted and yields reduced at application of grater than 4.5 kg B/ ha. Effect of boron levels on growth and yield of cauliflower in calcareous soil Plant spread The plant spread of cauliflower was increased with the increases of B levels up to 3 kg B/ha. Table 8. Effect of B levels on growth and yield components of carrot. Treatmen ts Shoot yield (t/ha) Root yield (t/ha) % Yield increase over control B 0 = Control 13.18 20.26 - B 1 = 1 kg B/ha 15.38 24.13 19.10 B 2 = 2 kg B/ha 18.56 28.48 40.47 B 3 = 3 kg B/ha 18.40 28.66 41.46 B 4 = 4 kg B/ha 17.85 27.31 34.79 B 5 = 5 kg B/ha 16.21 25.63 26.50 B 6 = 6 kg B/ha 15.17 23.17 14.36 LSD at 5% 2.06 1.78 - CV (%) 9.16 7.63 - In a column, figures having same letter(s) do not differ significantly by DMRT at the 5% level. The highest plant spread 65.63 cm was found at 3 kg B/ha and lowest in control. But the rate 3 and 4 kg are statistically similar. Plant spread The plant height of cauliflower was increased with the increases of B levels up to 4 kg B/ha. The highest plant height was found at 4 kg B/ha and lowest in control. Leaf size The largest leaf size like leaf length and breadth was significantly influenced by B levels. The biggest leaf size was found in B 4 and small size in control (B 0 ). Leaves per plant The number of leaves was increased gradually with B levels and maximum at 4 kg B/ha. Leaves weight The leaves weight of cauliflower was highest at 3 kg B/ha and lowest in control or 6 kg B/ha. Data showed that the vegetative growth of cauliflower was maximum by the application of 3-4 kg B/ha. Curd weight The edible curd weight per plant was recorded at harvest. Application of 3 kg B/ha gave the maximum curd weight per plant and the lowest weight in 6 kg B/ha. Curd size The curd size was measured at harvesting time. The biggest size of curd was observed when 3 kg B/ha as boric acid was applied and smallest in control plot. Gross and curd yield Gross yield or curd yield was measured in a unit plot and converted to kg/ha. The yield was gradually increased with the increase of B levels up to 3 kg/ha and then decreases. Application of 1, 2 and 3 kg B/ha increased the curd yield by 33.27, 58.31 and 70.84 % respectively over control (no B fertilizer). In table-6 showed that curd yields of cauliflower were 69 Hasan et al. Int. J. Biosci. 2025 significantly reduced without B application in calcareous soils. The results are in agreement with the findings of Alam (2007). Alam et al (2010) showed that application of 3 kg B/ha increased (27.74 %) the bulb yield of onion over control. Effect of boron levels on growth and yield of carrot in calcareous soil Plant height Application of B levels exhibited a significant influence on growth of plant height. The plant height was increased gradually up to 4 kg B/ha and then decreases gradually with B levels. The maximum plant height (52.13 cm) was recorded at 4 kg B/ha followed by 3 kg B/ha (51.46 cm) but both are statistically similar and lowest in control. Leaves per plant Application of 4 kg B/ha produced the maximum number of leaves of carrot but B levels 0, 1 and 2 kg/ha are statistically apart. Shoot weight Application of 3 kg B/ha produced the maximum weight of shoot of carrot but 2, 3 and 4 kg B/ha are statistically similar. Root length The root length was significantly influenced by B levels. The maximum root length was found at 4 kg B/ha but 2, 3 and 4 kg B/ha is statistically atpar and lowest in control. Root diameter Maximum root diameter of carrot was found in 3 kg B/ha but 2 and 3 kg B/ha are statistically similar and lowest in 6 kg B/ha or control. Root weight Application of B levels exhibited a significant influence on root weight of carrot. The maximum root weight was found at 3 kg B/ha but 2, 3 and 4 kg B/ha are statistically similar and lowest in control. Shoot yield Application of B increased the dry matter content in carrot plants. The fresh shoot yield was significantly influenced by the application of different doses of B. The maximum shoot yield 18.56 t/ha was obtained by 2 kg B/ha followed (18.40 t/ha) by 3 kg B/ha but both are statistically similar. The results are is partial agreement with the findings of Porter et al. (1986), Alam (2006), Alam (2007) and Alam et al. (2010). Table 9. Effect of B levels on growth and yield components of potato. Treatments Plant height (cm) No. of main stem /hill Wt. of haulm (G/hill) No. of tubers/hill Shoot yield (t/ha) Tuber yield (t/ha) % Yield increase over control B 0 = Control 39.96 2.90 43.00 6.13 3.33 19.33 - B 1 = 1 kg B/ha 42.73 3.07 46.36 7.56 4.65 22.36 15.67 B 2 = 2 kg B/ha 44.83 3.46 49.33 8.46 4.93 24.33 25.86 B 3 = 3 kg B/ha 49.76 3.63 56.33 8.57 5.18 28.56 47.74 B 4 = 4 kg B/ha 50.66 3.66 57.96 8.69 5.33 29.19 51.00 B 5 = 5 kg B/ha 48.90 3.23 53.67 7.43 4.63 26.23 35.69 B 6 = 6 kg B/ha 46.33 2.83 45.33 7.19 3.36 24.46 26.56 LSD at 5% 1.18 0.21 2.35 0.51 0.36 1.72 - CV (%) 6 .33 3.35 5.24 2.06 1.20 7.12 = In a column, figures having same letter(s) do not differ significantly by DMRT at the 5% level. Root yield Application of different doses of B influenced the yield of carrot. The root yield of carrot responded significantly to added boron up to 3.0 kg/ha, this dose gave an additional root yield of 41.46 % over control and decreased gradually with the increases of B level (>3.0 kg B/ha). The second highest but statistically similar root yield was found by the application of 2.0 kg/ha. The lowest yield (20.26 t/ha) was found when B was not applied. The finding are strongly supported by Hafiz Akter et al. (2001) and Pregno and Arour (1992). 70 Hasan et al. Int. J. Biosci. 2025 Table 10. Effect of B levels on growth and yield components of radish. Treatments Plant height (cm) No. of leaves/plant Length of largest leaf (cm) Breadth of largest leaf (cm) Length of root (cm) Diameter of root (cm) B 0 = Control 39.16 16.23 36.65 9.36 23.56 9.26 B 1 = 1 kg B/ha 44.63 19.09 38.25 10.46 26.52 10.61 B 2 = 2 kg B/ha 48. 25 23.36 41.33 10.97 28.87 11.27 B 3 = 3 kg B/ha 51.23 23.63 42.43 11.39 30.61 12.53 B 4 = 4 kg B/ha 51.46 24.13 42.14 11.33 29.40 13.02 B 5 = 5 kg B/ha 49.86 23.04 40.06 9.88 27.93 12.17 B 6 = 6 kg B/ha 46.51 22.75 38.11 9.23 26.11 11.64 LSD at 5 % 2.03 1.34 0.92 0.40 1.31 0.67 CV (%) 6.75 5.37 8.34 1.39 6.16 4.35 In a column, figures having same letter(s) do not differ significantly by DMRT at the 5% level. The results suggested that 2-3 kg B/ha (as boric acid) are applicable for carrot cultivation in calcareous or any upland soils of Bangladesh. Effect of boron levels on growth and yield of potato in barind soil Plant height The plant height of potato responded significantly with B levels. The highest plant height was recorded at 4 kg B/ha but 3 and 4 kg B/ha showed statistically similar plant height. Main stem per hill The maximum and similar plant height was found by 1, 2, 3, 4 and 5 kg B/ha. Application of 5 kg B/ha decreased the plant than control. Weight of haulm The maximum weight of haulm per hill of potato by 4 kg B/ha but 3 and 4 kg B/ha are statistically similar. Tubers per hill The number of tubers per hill influenced significantly by B levels. It is maximum in 3 Kg B/ha and the lowest in control. Shoot yield The shoot yield was increased up to 4 kg B/ha and then decreases gradually with B rate. Application of 5 kg B/ha significantly decreased the shoot yield than 4 kg B/ha. It indicates the stunted growth or toxicity of potato plants. Tuber yield Application of B levels exhibited a significant influence on tuber yield of potato. The maximum tuber yield (29.19 t/ha) was observed by 4 kg B/ha followed by 3 kg B/ha but both are statistically similar. This result is directly supported by Alam (2007). Application of 1, 2, 3, 4, 5 and 6 kg B/ha increased the tuber yield by 15.67, 25.86, 47.74, 51.00, 35.69 and 26.56 % respectively than control. Effect of boron levels on growth and yield of radish in barind soil Plant height The plant height was significantly influenced to B levels. Application of B increased the plant height and maximum (51.46 cm) at 4 kg B/ha followed by 3 kg B/ha (51.23 cm) both are statistically similar. Leaves per plant The number of leaves was increased by application of B fertilizer. The highest number (24.13) of leaves of radish was found at 4 kg B/ha but the rate 2-5 kg/ha responded similar number of leaves. The lowest number of leaves was found in control. Leaf size The leaf area was measured at harvesting time. The largest leaf size like leaf length and breadth was influenced significantly by B levels. The biggest leafsize was found at 3 kg B/ha .