Chili (Capsicum annum L.) is the world’s most famous, widely used and valuable spice cultivated around the globe. Pakistan is 6th largest exporter of chili, hence it is cultivated on largest area after potato and onion. Since couple of years, the production and export of chili in Pakistan is declining due to different constraints. Collar rot disease caused by fungus Sclerotium rolfsii Sacc., has been regarded as most destructive disease that affects chili growth and yield all over the world and in Pakistan as well. Besides, toxicity of heavy metal like chromium is another major environmental threat to agriculture that limits plant growth and reducing crop yield. Utilization of metal loaded wastewater to grow vegetable is a very common practice in Pakistan. Use of biofertilizers and soil amendments as allelopathic plants, organic and inorganic manure have been projected as emerging solution to combat such notorious pathogen as an alternative to expensive and cautionary chemical based procedures. The present study was conducted to manage the collar rot disease of chili by two commercial biofertilizers and soil amendments (allelopathic plants, organic and inorganic fertilizers) under abiotic stress of chromium. v In vitro screening bioassays were conducted to assess the disease management potential of methanolic leaf extracts of eight allelopathic plants namely Azadirachta indica L., Eucalyptus camaldulensis L., Melia azedarach L., Acacia nilotica subsp. indica (Benth.) Kyal. & Boatwr., Albizia lebbeck (L.) Benth., Prosopis juliflora (Sw.) DC., Syzygium cumini (L.) Skeels and Mangifera indica L. against S. rolfsii. Methanolic extracts of A. indica, E. camaldulensis, A. nilotica subsp. indica and M. azedarach were found highly effective in suppressing in vitro growth of S. rolfsii by 40–59%, 45–65%, 17–55% and 36–54%, respectively. Polarity-gradient sequential extracts (n-hexane, chloroform, ethyl acetate and n-butanol) of A. indica and E. camaldulensis were screened for their antifungal activity. The highest antifungal activity (91-97%) was recorded due to chloroform sub-fractions. Methanolic extract of M. azadarach and A. nilotica subsp. indica, while chloroform fractions of methanolic extracts of A. indica and E. camaldulensis were scrutinized through GC-MS identified many chemically and biologically active compounds comprised of phytol, quercetin, sesquiterpenes, carboxylic acid, aromatic dicarboxylic acid, methyl esters etc. v Leaf dry biomass of A. indica and E. camaldulensis were also checked for Cr(III) uptake potential from aqueous solution that showed 50-70% Cr(III) uptake potential by the former and 70-80% by the later adsorbent. Fourier Transform Infrared Spectroscopy of leaf biomass of both the adsorbent confirmed involvement of hydroxyl, carboxylic, carbonyl, amino and nitro groups in metal binding. v Laboratory experiments were further extended to determine Cr(III) tolerance by S. rolfsii both in solid and liquid growth medium within metal concentration range of 10-500 ppm. The fungal growth was declined by ~70% at 100 ppm and completely halted from 200-500 ppm. v In virto and in vivo trials were carried out to assess effect of various concentration (10-500 ppm) of Cr(III) on growth of chili. There was 30-90% reduction in germination, growth and biomass of chili plants due to 50-200 ppm and plants were died or unable to grow beyond this concentration. v Results derived from different laboratory trails were used to conduct pot experiments. In the first and second pot experiments, the effect of different doses (1% to 4%) of dry leaf biomass A. indica and E. camaldulensis was studied on disease incidence, plant mortality growth and physiology of the host plant. The results of these soil amendments were not very much encouraging. However, 3% dose of each of the two soil amendments reduced incidence and mortality of the plants by 27-55% and 12-43%, respectively, over positive control treatment. In third experiment, the effect of two commercial biofertilizers namely Biopower (BF 1) and Feng Shou (BF 2) in combination with recommended and half doses of NPK fertilizers was studied on disease incidence, plant mortality, plant growth and physiology. Likewise, in the fourth experiment, these biofertilizers were used in combination with 1% and 2% farmyard manure (FYM). Both the biofertilizers significantly reduced disease incidence due to collar rot disease and plant mortality in combination with either NPK fertilizers or FYM amendment. Biopower 2 was proved comparatively better than Biopower 1 in improving crop growth under biotic stress of S. rolfsii. Biofertilizers had variable effects on various physiological parameters viz. chlorophyll and protein contents, and polyphenol oxidase (PPO) and peroxidase (PO) activities in different soil amendment systems. v The fifth experiment was carried out by selecting the most suitable treatments for disease management from the experiments 1 to 4 (3% dry leaf biomass of each E. camaldulensis and A. indica, and 2% FYM as soil amendments, and Biopower 2) and studied their efficacy in management of collar rot disease under abiotic stress of Cr(III) (100 ppm).p In general, plant mortality, root and shoot growth and chlorophyll contents were reduced by Cr(III) application as compared to corresponding treatments without Cr(III). Soil amendments with 2% FYM combined BF 2 resulted in comparatively better shoot and root growth under combined stress of S. rolfsii and Cr(III). The present study concludes that 2% FYM in combination with commercial biofertilizer Feng Shou can be used as soil amendment for better plant growth in chili in S. rolfsii infested soils under abiotic stress of Cr(III).