International Journal of Advances in Scientific Research and Engineering (ijasre) E-ISSN : 2454-8006 DOI: 10.31695/IJASRE.2024.6.6 Volume 10, Issue 6 June - 2024 https://ijasre.net/ Page 53 Appraising the Effect of Biochar in Groundnuts(Arachis hypogaea L) Growth Parameters and Yield Under Screen House Conditions Joshua J. Ibrahim* 1 , Ernest Mbega 1 , Angela Mkindi 1 , Arnold Mushongi 2 , Billes L. Nzilano 3 1 Department of Life Sciences and Bioengineering, The Nelson Mandela African Institution of Science and Technology(NM-AIST), Box 447, Arusha, Tanzania 2 Tanzania Agricultural Research Institute (TARI) Ilonga Centre, P.O. Box 33, Kilosa, Morogoro, Tanzania 3 Tanzania Agricultural Research Institute (TARI) Uyole Centre, P.O. Box 400, Mbeya, Tanzania ______________________________________________________________________________________________ ABSTRACT Biochar soil amendment is known to suppress the effect of pathogenic fungi and favour plant resistance against soil ‐ borne pathogen effects. This study appraises the impact of biochar on groundnut yield planted in the slightly acidic sandy loam soil. The study was done at the Nelson Mandela African Institution of Science and Technology (NM-AIST) screen house, where groundnuts were planted in the 2L pots filled with soil mixed with biochar at different rates (2.5%, 5% and 7.5%) in April 2022. Groundnut’s growth parameters were managed by measuring shoot length and root length, counting the number of leaves and taking leaf area once every week from the second week after planting to harvesting, where its yield was also measured. Analysis of variance showed a significant (P < 0.05) increase in groundnut growth parameters and yield when 5% Biochar was used. There was a strong positive correlation between biochar and some groundnut growth parameters. No significant (P < 0.05) difference was observed between Biochar and groundnut growth parameters and yield when 2.5% biochar was used. A slightly weak negative correlation was observed when a 7.5% Biochar rate was used. Biochar-amended soils indicated a dramatic increase in soil pH, CEC, Mn, P, K, Ca, B, Zn and Si. The current study indicates that the utilization of 5% maize cob biochar, pyrolyzed at 500°C, in acidic sandy loam soil, can lead to maximum enhancement in soil physical and chemical properties, as well as groundnut growth and yield parameters. Keywords: Biochar, Groundnuts, Growth parameters, Soil, Soil nutrient. _______________________________________________________________________________________________ 1. INTRODUCTION Groundnut (Arachis hypogaea L.) is one of the leguminous crops presented to Africa from Brazil in the 16 th century (Daudi et al., 2018). It is the most significant crop for smallholder farmers in Tanzania for the provision of food, feed, and income (Mfaume et al., 2019). The crop is grown in different types of soils, preferably with more than fifty per cent sand, with pH range of 4.8 to 7 (Daudi et al., 2018). Heavy soils cause water logging and detachment of seeds during harvest. Nutritionally, groundnut is rich in fat, protein, carbohydrates, vitamins, and minerals (Abady et al., 2019). It is the world's 13th most consumed food crop, fourth for cooking oil, and third for essential proteins (Daudi et al., 2018). This crop is a native New World crop where early pioneers found it cultivated broadly in both Meso and South America (Abady et al., 2019; Alam et al., 2020; Daudi et al., 2018). It is described that groundnut remnant pericarp tissue recovered from archaeological sites in Peru dates its purposeful agricultural use to around 3900-3750 years ago (Mfaume et al., 2019). The domestication of this crop is supported by archaeological records between 300 and 2500 BC in Peruvian desert oases and likely first occurred in the valleys of the Paraguay and Parana rivers in the Chaco region of South America (Daudi et al., 2018). In Africa, the Portuguese presented groundnuts from Brazil in the 16 th century (Mwatawala & Kyaruzi, 2019). Frank Samuel, head of the United Africa Company, came up with the idea