Effect of Bacillus pumilus Strains on Heavy Metal Accumulation in Lettuce Grown on Contaminated Soil

Sabeen Alam *

Department of Horticulture, Faculty of Crop Production Sciences, The University of Agriculture, Peshawar, Pakistan.

Mehboob Alam

Department of Horticulture, Faculty of Crop Production Sciences, The University of Agriculture, Peshawar, Pakistan.

Hafsa Naeem

Department of Plant Pathology, The University of Agriculture, Peshawar-Khyber Pakhtunkhwa, Pakistan.

Muhammad Adeel

Faculty of Agriculture, Near East University, Nicosia, North Cyprus.

Adil Riaz

Faculty of Agriculture, Near East University, Nicosia, North Cyprus.

Usama Zeb Awan

Department of Horticulture, Pir Mehr Ali Shah Arid Agriculture University, 44000, Rawalpindi, Pakistan.

Abdul Basit

Department of Horticultural Science, Kyungpook National University, 41566, Daegu, South Korea.

Burhan Ullah

Department of Biosciences, Comsats University Islamabad, Pakistan.

*Author to whom correspondence should be addressed.


Increasing number of heavy metal on land needs to be addressed through sustainable ways and various species of Bacillus can be used to mitigate heavy metals. The research work entitled “Effect of Bacillus pumilus strains on heavy metal accumulation in lettuce grown on contaminated soil” focuses on functional role of Bacillus pumilus strains inoculated with lettuce seed in mitigating heavy metal present in chromite mining soil. This experiment was conducted at ornamental horticulture nursery, the University of Agriculture Peshawar. In this experiment, factor A was three Bacillus pumilus strains (sequence C-2PMW-8, C-1 SSK-8 and C-1 PWK-7) while soil used for this experiment was collected from Prang Ghar mining site and lettuce seeds were grown in three levels of chromite mining soil (2.27, 4.65 and 7.14 %).The experimental design used during this research was randomized complete block design with two factors and was replicated thrice. The collected data related to effect of chromite mining soil and Bacillus pumilus strains indicated that these both factors have significant influence on growth parameters. For mining soil minimum days to germinate (14 days) was noted in lettuce grown on garden soil inoculated with sequence. Maximum germination percentage noted was (100%) for C-1 SSK-8 grown on garden soil, dry weight of lettuce leaf (5.0 g) for lettuce inoculated with C-1 SSK-8 and C-1 PWK-7 strains, survival percentage (77.9%) for C-1 SSK-8 treated lettuce for sequence C-2 PMW-8. Maximum germination percentage noted was (88%) for garden soil, fresh leaf weight (17.3g), dry leaf weight (6.5g), number of leaf per plant (16), leaf area (49.0 cm2) were noted in garden soil with no chromite mining soil. Results related to heavy metals accumulation showed that minimum chromium was (2.3 mg kg-1) in lettuce and (1.9 mg kg-1) in soil for all three sequences. It can be concluded that chromite mining soil significantly reduced the growth and survival of lettuce, but when lettuce was inoculated with Bacillus.pumilus strains it enhances the growth and survival. Similarly, minimum heavy metal accumulation in plant and soil, regardless of type of B. pumilus used, all three sequences has same mitigating effect on heavy metal in both soil and lettuce. All the three Bacillus pumilus strains ensured reduction in heavy metals content (Cr) in lettuce, below the maximum permissible limits of WHO/FAO 2011.

Keywords: Bioremediation, lettuce, heavy metal, permissible limits and Bacillus strains, Bacillus pumilus, atomic density, soil modification

How to Cite

Alam, S., Alam , M., Naeem , H., Adeel, M., Riaz , A., Awan , U. Z., Basit, A., & Ullah , B. (2024). Effect of Bacillus pumilus Strains on Heavy Metal Accumulation in Lettuce Grown on Contaminated Soil. Asian Journal of Research in Crop Science, 9(2), 10–20. https://doi.org/10.9734/ajrcs/2024/v9i2262


Download data is not yet available.


Torresdey JLG, Videa JRP, Rosa GDL, Parsons JG. Phytoremediation of heavy metals and study of the metal coordination by X-ray absorption spectroscopy. Coord. Chem. 2005;249:1797–1810.

Pink DAC, Keane EM. Lettuce: Lactuca sativa L. Chapter 40. In: Kallo G, Bergh BO (eds). Genetic improvement of vegetable crops. Pergamon press. UK. 2012; 543-571.

Ministry of national food and security and research. Fruit, vegetable and condiments statistics of Pakistan 2018-2019; 2020. Available:http://www.mnfsr.gov.pk/frm

Jean SY, Bernard YO, Cyrill YDA. Heavy metals contamination in Lactuca sativa (Lettuce) from two agricultural sites of Abidjan. Int. J. Pure Appl. Sci. 2015;27(2):59-64.

Achankzai AKH, Bazai ZA, Kayani SA. Accumulation of heavy metals by lettuce (Lactuca sativa L) irrigated with different levels of wastewater of Quetta city. Pak. J. Bot. 2011;43(6):2953-2960.

Musa DM, Garba Y, Sani MD. Potential of lettuce (Latuca sativa) for phytoremediation of Cd, Cu, Cr and Pb in contaminated soil along river salanta. Agr. Plant. Sci. 2017;3(2):258-269.

Hayes WJ, Chaudhry RT, Buckney RT, Khan AG. Phytoaccumulation of trace metals at the Sunny Corner mine, New South Wales, with remediation strategy. Aust. J. Ecotoxicology. 2003;9(1):69–82. .

Masood S, Zhao XQ, Shena RF. Bacillus pumilus promotes the growth and nitrogen uptake of tomato plants under nitrogen fertilization. Sci. Hortic. 2020;272:1-9.

Shahzad A, Qin M, Elahia M, Naeem M, Bashir T, Yasmin H, Younas M, Areeb A, Irfan M, Billah M, Shakor A, Zulfiqar S. Bacillus pumilus induced tolerance of Maize (Zea mays L.) against cadmium stress. Sci. Rep. 2021;11(1):1-11.

Dasgupta S, Sengupta S, Saha S, Sarkar A, Anantha KC. Approaches in advanced soil elemental extractability: Catapulting future soil–plant nutrition research. In: Rakshit A, Singh SK, Abhilash PC Biswas A. (eds) Soil Science: Fundamentals to Recent Advances. Springer, Singapore; 2021.

Jan MT, Shah P, Hollington PA, Khan MJ, Sohail Q. Agriculture research: Design and analysis, Department of Agronomy, Agriculture University Peshawar, Pakistan; 2009.

Miljakovic D, Marinkovic J, Balesevic-Tubic S. The significance of Bacillus spp. in disease suppression and growth promotion of field and vegetable crops. 2020; 8(7):1037.

Yuan Y, Gao M. Genomic analysis of a ginger pathogen Bacillus pumilus providing the understanding to the pathogenesis and the novel control strategy. Sci. Rep. 2015;5(1):1-9.

Tiwari S, Lata C. Heavy metal stress, signaling, and tolerance due to plant-associated microbes: an overview. Front. Plant Sci. 2018;9:452.

Qureshi AS, Hussain MI, Ismail S, Khan QM. Evaluating heavy metal accumulation and potential health risks in vegetables irrigated with treated wastewater. Chemosphere. 2016;163: 54-61.

Upadhyay N, Vishwakarma K, Singh J, Mishra M, Kumar R, Rani R, Mishra RK, Chauhan DK, Tripathi DK Sharma S. Tolerance and reduction of chromium (VI) by Bacillus sp. MNU16 isolated from contaminated coal mining soil. Front. Plant Sci. 2017;8:778.

Ahemad M. Enhancing phytoremediation of chromium-stressed soils through plant-growth-promoting bacteria. J. Genet. Eng. Biotechnol. 2015;13(1):51-58.

Wani PA, Khan MS. Bacillus species enhance growth parameters of chickpea (Cicer arietinum L.) in chromium stressed soils. Food. Chem. Toxicol. 2010;48(11): 3262-3267.