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To cite this paper: Chohan, S. and R. Perveen, 2015. Phytochemical analysis and antifungal efficacy of rhizome extracts of various plants against fusarium wilt and root rot of tomato. lycopersici, whereas, least inhibition was observed against F. solani. Correspondingly, conidial germination of test fungi was almost completely reduced by A. sativum extract. Phytochemical screening of crude extract revealed the presence of flavonoids, terpenes, saponins, whereas, A. sativum was also found rich in steroids, tannins, glycosides and coumarins. Tannins were not detected in C. longa. Total phenol contents (TPC) were present in highest quantity ((54.24GAEmg/g) in A. sativum followed by Z. officinale (29.80GAEmg/g), whereas, rhizomes of C. longa contained lowest TPC (25.45GAEmg/g). It was concluded that rhizome extracts of A. sativum possesses sufficient antifungal activity under controlled conditions to warrant a further investigation under field conditions.

Black scurf disease of potato, caused by fungus Rhizoctonia solani, is the most common and one of the oldest diseases of potato affecting stem and stolons. In recent years, the disease is reportedly present in the fields of potato in Pakistan especially in Punjab. Survey of different locations viz. Narangaabad, Band Bosan, Kaian Pur, Kotla Abdul-Fateh and Dhillun was conducted to assess the prevalence of disease in Multan region. Maximum disease incidence and severity of 95.00% and 3.1 rating, was recorded in Kotla Abdul-Fateh respectively. Sclerotial pieces showing characteristic symptoms of black scurf were detached from tuber surface and the fungus was isolated on potato dextrose agar medium. For in-vitro chemical and biotic elicitor testing, three different fungicides viz., Monceren, Topsin-M, and Triton were evaluated using poisoned food technique and antagonistic effect of two accessions of Triochoderma spp. viz. Trichoderma harzianum and Trichoderma viridae was determined against the sensitivity of fungus. Triton was found to be superior at all concentrations in inhibiting the radial mycelial growth of the fungus followed by Topsin-M and Monceren. Satisfactory results were obtained by the antagonistic effect of Trichoderma harzinaum and Trichoderma viridae with 70.00% and 66.00% respectively under in-vitro conditions. Although the fungicide chemistries exclusively control the fungus yet the evaluation of bioagents also remained prolific towards antagonism against Rhizoctonia solani. These investigations provide fresh information on the current status of black scurf disease of potato in fields of Multan and regarding the biochemical management against Rhizoctonia solani under in-vitro conditions and serve as a guide for the future prospects against this holistic disease.

In agriculture, fungal invasions cause heavy loss and affect food security and food safety. Chemical pesticides are available to control these pathogens but these are associated with environmental and public health concerns. In recent years, there is a growing trend towards nature friendly methods of pathogen control. Use of allelochemicals from mushrooms is a promising field. In the present study, antifungal activity of an edible mushroom, Agaricus bisporus was investigated. For this purpose, different organic solvent extracts of A. bisporus, were evaluated against plant pathogenic fungal species viz. Macrophomina phaseolina, Aspergillus flavus, Fusarium oxysporum, Drechslera australiensis and Alternaria alternata. To check the antifungal activity of A. bisporus, serial dilution method was used. Six levels of treatments of each n-hexane, chloroform and ethyl acetate (0, 5, 10, 15, 20 and 25 mg/ml) were applied against all fungal species. Generally, all organic solvent extracts reduced the fungal biomass significantly with the increase in concentration but, ethyl acetate fraction exhibited better results and reduced the fungal growth in some species up to 50% in D. australiensis and 44% each in A. alternata and F. oxysporum. From Gas Chromatography Mass Spectrometry (GCMS) analysis of ethyl acetate fraction, 10 compounds were identified. Out of these 10 compounds, only one compound [1,2-Benzenedicarboxylic acid, mono (2-ethylhexyl) ester], molecular formula = C16H22O4 and molecular weight = 278, showed 91.31% peak value. It was concluded that this compound being in the highest concentration in the ethyl acetate fraction of A. bisporus mushroom was responsible for its antifungal activity, recorded in the present study. The present investigation concluded that A. bisporus has bioactive compounds that can be exploited to develop ecofriendly fungicides against a number of plant pathogens.