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Endophytic fungi live inside plant tissues but do not cause any disease. Several reports have now revealed that they have great influence on host. In this study, the beneficial role of endophytic fungi is highlighted and explored. Endophytic fungi isolated from healthy plants were identified as Aspergillus terreus, Curvularia lunata, C. hawaiiensis, Macrophomina phaseolina, Fusarium solani, Talaromyces assiutensis, and T. trachyspermus using 18S rRNA gene sequencing. In vitro, fungi evaluated for antimicrobial activity, showed significant activity. These fungi were tested in field application by exploring their broad spectrum. Talaromyces assiutensis and T. trachyspermus were applied in pots and field plot experiments using sunflower as test plants, along with endophytic Cephalosporium sp., and Chaetomium sp. Endophytic fungi showed significant activity against root rot pathogens affecting sunflower and improved plant biomass. They also improved production of plant defense biochemical markers (polyphenolic content and salicylic acid) with improvement in antioxidant potential. These fungi are used as biological control agents, so their culture filtrates are used to check the presence of metabolites by GC-MS. Several new compounds were isolated from T. assiutensis. The major bioactive compounds are Coumarin, 3,4-dihydro-6-methoxy-4,4-dimethyl, 1-Monolinoleoylglycerol trimethylsilyl ether, 1,2-Propanediol, 3-(octadecyloxy), Ethyl iso-allocholate, and 1H-Pyrazole, which possess antioxidant, antitumor, antibacterial, anticancer, and antimicrobial properties. These findings will lead to further in-depth research toward the potential use of these endophytic fungi for their possible use in agriculture and drug formation.

Several reports revealed that endophytic fungi have great influence on host plants, as they promote plant growth and minimize disease severity caused by various pathogens. In this study, endophytic fungi isolated from healthy plants were identified as Aspergillus terreus, Curvularia lanata, C. hawaiiensis, Macrophomina phaseolina, Fusarium solani, Talaromyces assiutensis and T. trachyspermus were evaluated for antimicrobial activity, using dual-culture plate assay and agar disc diffusion method. They have shown significant activity against root rot pathogens, Macrophomina phaseolina, Rhizoctonia solani, Fusarium solani and F.oxysporum. Talaromyces assiutensis and T. trachyspermus were selected for further study, since other fungi are well known plant pathogens or environmental contaminants. They were applied in pots and field plot experiments using sunflower as test plant. There efficacy was also compared with endophytic Cephalosporium sp., and Chaetomium sp. Talaromyces spp., significantly suppressed root rotting fungi and improved plant biomass. They ameliorated production of plant defense biochemical markers (polyphenolic content and salicylic acid) and antioxidant potential of treated plants. GC-MS profiling of n- hexane fraction of T. trachyspermus yielded several new compounds from this source. Endophytic fungi associated with healthy plants have great potential to suppress root rotting fungi and stimulate production of plant’s defense biochemical markers.

Fisetin, 2-(3,4-dihydroxyphenyl)-3,7-dihydroxychromen-4-one, is a plant flavonoid initially isolated from Rhus cotinus L. This bioactive molecule often occurs in herbal teas and strawberry and has been extracted using aqueous methanol, water, and supercritical fluids. Besides keeping in view its pharmacological importance, microorganism such as yeast (Saccharomyces cerevisiae) and certain bacteria such as Escherichia coli have been successfully engineered for the enhanced production of fisetin from 4-coumaric acid and amino acids. The evaluation of available clinical records indicated that the oral administration of fisetin especially late in life (old age) can restore tissue homeostasis, inflammations, and certain type of cancers such as lung, bladder, breast, and blood cancer. Moreover, the administration of fisetin to wild-type mice late in life restored tissue homeostasis and control senescence-associated secretory phenotypes to extend the median and maximum lifespans.

Rhizobia are soil bacteria, characterized by their unique ability to colonize the roots of leguminous crops, where they form nitrogen fixing nodules. Considerable evidence has been accumulated to identify the benefits associated with use of rhizobia as biocontrol agents against soil-borne pathogens, in addition to biological nitrogen fixation. In this study, out of four rhizobial isolates tested, Bradyrhizobium sp. inhibited the radial growth of all the test fungi viz: Macrophomina phaseolina, Rhizoctonia solani, Fusarium solani and F. oxysporum, while other 3 rhizobial isolates inhibited the growth of at least three fungi. Cell free culture filtrates of rhizobia also showed nematicidal activity by killing second-stage juveniles of Meloidogyne javanica at varying degrees. Application of rhizobial isolates alone or in mustard cake amended soil significantly (p

With the rising awareness of the adverse effects of chemical pesticides, people are looking for organically grown vegetables. Consumers are increasingly choosing organic foods due to the perception that they are healthier than those conventionally grown. Vegetable crops are vulnerable to a range of pathogenic organisms that reduce yield by killing the plant or damaging the product, thus making it unmarketable. Soil-borne diseases are among the major factors contributing to low yields of organic produce. Apart from chemical pesticides there are several methods that can be used to protect crops from soil-borne pathogens. These include the introduction of biocontrol agents against soil-borne plant pathogens, plants with therapeutic effects and organic soil amendments that stimulate antagonistic activities of microorganisms to soil-borne diseases. The decomposition of organic matter in soil also results in the accumulation of specific compounds that may be antifungal or nematicidal. With the growing interest in organic vegetables, it is necessary to find non chemical means of plant disease control. This review describes the impact of soil-borne diseases on organic vegetables and methods used for their control.

Ciprofloxacin (CIP), an important class of antibiotics is greatly used and discharged into aquatic environment which causes severe environmental issues. In this study, nano-scaled, stable, and highly reactive zerovalent copper (Cu°) was synthesized for the treatment of ciprofloxacin (CIP) in aqueous solution. The Cu° is an important material due to its high reduction potential and thus significantly degrade emerging organic pollutants. Besides, the Cu° synthesized in this study showed good surface area (i.e., 16.89 m2/g) and caused 63 % removal of CIP at 105 min under the conditions of [Cu°]0 = 0.5 g/L and [CIP]0 = 10 ppm. However, when H2O2 was used with Cu°, the removal of CIP was promoted from 65 to 85 % at 105 min using [Cu°]0 = 0.5 g/L, [CIP]0 = 10 ppm, and [H2O2]0 = 40 ppm,. CIP removal by Cu°/H2O2 was due to ●OH that showed high reactivity, i.e., 3.95 × 109 (M s)–1 towards CIP. The use of high [H2O2]0 and [Cu°]0 but lower [CIP]0 promoted the removal of CIP. The change in pH, addition of inorganic ions, and use of ●OH scavengers also influenced the removal of CIP by Cu°/H2O2. Total organic carbon (TOC) removal of CIP was investigated and showed 78 % removal of TOC at 800 min. Degradation products (DPs) of CIP were investigated to establish degradation pathways. The Cu°/H2O2 was found to have high potential in the removal of CIP in aqueous solution as it resulted in high TOC removal of CIP, and formation of inorganic DPs and non-toxic acetate.

Without application of chemical pesticides control of soilborne diseases is a great challenge. Stimulation of natural plant's defense is considered as one of the most promising alternative strategy for crop protection. Organic amendment of soil besides direct suppressing the pathogen, has been reported to have an influence on phytochemicals in plants. In the present study, Pseudomonas aeruginosa, a plant growth promoting rhizobacterium and Paecilomyces lilacinus, an egg parasite of root knot and cysts nematodes were examined individually and in combination in soil amended with cotton cake for suppressing the root rotting fungi and stimulating the synthesis of polyphenols and improving the antioxidant status in okra. Application of P. aeruginosa and P. lilacinus in soil amended with cotton cake significantly (P < 0.05) suppressed Macrophomina phaseolina, Fusarium oxysporum, and Fusarium solani with complete reduction of Rhizoctonia solani. Combine use of biocontrol agents in cotton cake amended soil showed maximum positive impact on plant growth, polyphenol concentration and antioxidant activity in okra.