Effect of Gas Flaring on Some Phytochemicals and Trace Metals of Fluted Pumpkin (Telferia Occidentalis)

The study determined the impact of gas flaring on some phytochemical and trace metal compositions of Telferia occidentalis in Obrikom, a gas flaring community. Plants for the study were obtained from farmlands in the gas flaring community in Rivers State, Nigeria and values obtained were compared with those from non gas flaring community (Rumualogu). The phytochemical composition (mg/100g) of Telferia occidentalis leaves grown both in gas flaring and non gas flaring sites was measured. The results obtained from non-gas flaring community are alkaloid (3.34 ± 0.006), flavonoid (6.67±0.009), saponins (8.21±0.020) and tannins (0.01±0.001) while the values from the gas flaring community are alkaloid (2.18±0.004), flavonoid (0.83±0.001), saponins (2.22±0.009) and tannins (0.46±0.012). The findings showed that plants in gas flaring community had reduced phytochemicals except tannins which increased significantly (P>0.05). There was significant increase (P>0.05) in the levels of Fe (2.78±0.01 to 3.51±0.02), Zn (0.90±0.06 to 1.30±0.02), Pb (0.21±0.01 to 0.54±0.01) and Cd (0.00±0.00 to 0.07±0.01) when the leaves grown in a non gas flaring site were compared with the gas flaring site samples. However, there was no significant difference in Cr concentration of the vegetable from both sites; Cr (0.2±0.01 to 0.06±0.01). All these may have possible implication on the nutritional and medicinal values of Telferia occidentalis. Keywords: Gas flaring, Phytochemicals,Trace metals

Potential of Nanoscale Elements to Control Fusarium Wilt Disease in Tomato (Solanum lycopersicum), Enhance Macronutrient Use Efficiency, and Increase Its Yield

Nanotechnology has a great potential in ensuring food production, security and safety globally. Over the past decade, research on the use of nanomaterials to supply nutrient elements and protect plants from pest and diseases has significantly increased. Tomato (Solanum lycopersicum) is one of the most consumed vegetables in the world and United State is one of its largest producers globally generating billions of dollars annually in revenue.. Tomato plants are affected worldwide by Fusarium wilt caused by Fusarium oxysporum f. sp. Lycopersici. There is growing concern about excessive use of conventional pesticides in controlling Fusarium and other diseases in tomato production. Nanoparticles have been reported to potentially increase plant growth and yield, and improve the nutritional value by enhancement of essential micronutrient required by the plants. However, little is known about the impact of nanoparticle elements on disease suppression, in tomato. This research was aimed at evaluating the potential of nanoscale elements in suppression of Fusarium wilt disease in tomato, enhance macronutrient use efficiency, and increase its yield. The research was developed in two phases. In the first phase, three week-old Bonny Best cultivar seedlings were exposed, by root or foliar pathways, to CeO2 nanoparticles and cerium acetate at 50 and 250 mg/L prior to transplant into sterilized soil. One week later, the soil was inoculated with the fungal pathogen F.oxysporum f. sp. lycopersici (1 g/kg) and plants were cultivated to maturity in a greenhouse.. Disease severity was significantly reduced by 250 mg/L of nano-CeO2 and CeAc applied to the soil (53% and 35%, respectively) or foliage (57% and 41%, respectively), compared with non-treated infested controls. In addition, Fusarium infection decreased fruit height (10%), dry weight (42%) and lycopene (17%), and increased the total sugar (60%) and Ca content (140%) in infested untreated control, compared with the non-infested untreated control (p ≤ 0.05). Foliar exposure to NP CeO2 at 250 increased the fruit dry weight (67%) and lycopene content (9%) in infested plant, compared with the infested untreated control. Foliar exposure to CeAc at 50 mg/L reduced fruit fresh weight (46%), and water content (46%), and at 250 mg/L increased fruit dry weight (94%), compared with infested untreated control. Fruit lycopene content also increased by 11% in infested plants exposed to CeAc at 50 mg/kg via root, compared with untreated infested control. Total sugar contents decreased in fruits of infested plants exposed via roots to NP CeO2 at 50 mg/kg (63%), at 250 mg/kg (54%), CeAc at 50 mg/kg (46%), and foliarly at 50 mg/L (50%) and 250 mg/L (50%), compared with infested untreated control. Overall, the findings show that nano-CeO2 has potential to suppress Fusarium wilt, improve the chlorophyll content in tomato plants and has negligible effects on the nutritional value of tomato fruit. In the second phase, we investigated the physiological and biochemical effect of copper oxide nanoparticles on tomato plant grown in F. oxysporum infested soil. Bonny Best tomato seedlings (three weeks old) were exposed to copper oxide nanoparticles (nCuO at 250 or 500 mg/L, root and foliar), CuSO4 (25 or 50 mg/L, foliar) and commercial fungicide, Kocide 3000, and transplanted into pots containing 1 kg sterilized soil mixture (1 natural: 2 potting mix). Seven days after the transplant, a group was inoculated with Fusarium (1 g/kg soil ~100,000 colonies) and cultivated in a greenhouse until the flowering stage (5 weeks after transplant). The root and shoot physiological parameters, biomass, plant height, chlorophyll content, enzyme activities (polyphenol oxidases and catalase), total proteins, micro, and macro elements were evaluated. Chlorophyll content reduced by 11% in infested control, relative non-infested control but increased in plants exposed to CuSO4 at 25 mg/L (8%) and 50 mg/L (9%), compared with infested untreated control (p ≤ 0.05). Chlorophyll content was elevated in plants treated foliarly with nCuO at 250 (10%), 500 (14%), and CuSO4 (15%), and via root to nCuO at 500 mg/kg (14%), compared with plant treated with Kocide 3000. Root exposure to nCuO at 500 mg/kg increased Shoot fresh weight by 18%. Root fresh weight increased in plant exposed to foliar treatment with nCuO at 250 mg/L (36%), and root exposure at 250 and 500 mg/kg by 33%, compared with untreated infested control. Root polyphenol oxidase and catalase activities increased plant exposed via root to nCuO at 500 mg/L (178%), and foliarly with CuO at 250 mg/L (138%), respectively, compared with untreated infested control. Overall, nCuO improved the chlorophyll content, increased plant biomass, and improve defense mechanism against the pathogen. This study revealed that the tested nanoparticles (CeO2 and CuO) has the ability to suppress Fusarium wilt disease in tomato, improve its chlorophyll content, and increase its yield and alter the nutritional content, and rely on antioxidant and microbial properties of Ce and Cu. These findings opens an opportunity for utilization of these nanoparticle as fungicides. Therefore, formulations containing nanoparticle micronutrients may proffer a new strategy that can suppress plant diseases and increase the yield. However, more research work needs to be done to fully understand the mechanism behind the nanoparticle-pathogen interaction in plants

Investigations on Implications of Gas Flaring on Some Phytochemicals and Trace Metal Content of Bitter leaf (Vernonia amygdalina)

The effect of gas flaring on some phytochemicals and trace metals in Vernonia amygdalina in Obrikom, a gas flaring community (GF) and Rumualogu, a non gas flaring community (NGF) in Rivers state, Nigeria was investigated. There was significant increase (P>0.05) in the composition of alkaloid (NGF; 1.32±0.044 and GF; 3.10±0.001) and tannin (NGF; 0.03±0.001 and GF; 0.31±0.007) in the Vernonia amygdalina when the leaf samples from Rumualogu(NGF-Community) was compared with the Obrikom(GF-Community) samples. However, there was no significant difference (P<0.05) in the flavonoid (NGF; 0.79±0.012 and GF; 0.88±0.009) and saponin (NGF; 1.20±0.009 and GF; 1.27±0.018) compositions. There was significant increase (P>0.05) in the levels of Fe (2.21±0.01 to 2.96±0.01), Zn (0.86±0.01 to 1.10±0.01) and Pb (0.14±0.03 to 0.29±0.02) when the leaves grown in a non gas flaring site were compared with the gas flaring site samples.  There was no significant difference in Cr concentration; Cr (0.01±0.01 to 0.02±0.01). Cadmium level was below detection limit (BDL) in the vegetable from both sites. The implication of these findings is a possible change on the nutritional and medicinal values of Vernonia amygdalina. Keywords: Gas flaring, Obrikom, Phytochemicals, Rumualog

Effects of Manganese Nanoparticle Exposure on Nutrient Acquisition in Wheat (Triticum aestivum L.)

Nanoparticles are used in a variety of products, including fertilizer-nutrients and agro-pesticides. However, due to heightened reactivity of nano-scale materials, the effects of nanoparticle nutrients on crops can be more dramatic when compared to non nano-scale nutrients. This study evaluated the effect of nano manganese-(Mn) on wheat yield and nutrient acquisition, relative to bulk and ionic-Mn. Wheat was exposed to the Mn types in soil (6 mg/kg/plant), and nano-Mn was repeated in foliar application. Plant growth, grain yield, nutrient acquisition, and residual soil nutrients were assessed. When compared to the control, all Mn types significantly (p < 0.05) reduced shoot N by 9–18%. However, nano-Mn in soil exhibited other subtle effects on nutrient acquisition that were different from ionic or bulk-Mn, including reductions in shoot Mn (25%), P (33%), and K (7%) contents, and increase (30%) in soil residual nitrate-N. Despite lowering shoot Mn, nano-Mn resulted in a higher grain Mn translocation efficiency (22%), as compared to salt-Mn (20%), bulk-Mn (21%), and control (16%). When compared to soil, foliar exposure to nano-Mn exhibited significant differences: greater shoot (37%) and grain (12%) Mn contents; less (40%) soil nitrate-N; and, more soil (17%) and shoot (43%) P. These findings indicate that exposure to nano-scale Mn in soil could affect plants in subtle ways, differing from bulk or ionic-Mn, suggesting caution in its use in agriculture. Applying nano Mn as a foliar treatment could enable greater control on plant responses

Seed Biofortification by Engineered Nanomaterials: A Pathway to Alleviate Malnutrition?

Micronutrient deficiencies in global food chains are a significant cause of ill health around the world, particularly in developing countries. Agriculture is the primary source of nutrients required for sound health, and as the population has continued to grow, the agricultural sector has come under pressure to improve crop production, in terms of both quantity and quality, to meet the global demands for food security. The use of engineered nanomaterial (ENM) has emerged as a promising technology to sustainably improve the efficiency of current agricultural practices as well as overall crop productivity. One promising approach that has begun to receive attention is to use ENM as seed treatments to biofortify agricultural crop production and quality. This review highlights the current state of the science for this approach as well as critical knowledge gaps and research needs that must be overcome to optimize the sustainable application of nano-enabled seed fortification approaches.Jason C. White acknowledges United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) Hatch CONH00147 and USDA NIFA AFRI 2020-67022-32416. Jorge Gardea-Torresdey acknowledges USDA Grant 2016-67021-24985 NIFA, partial funding from National Science Foundation (NSF) ERC-1449500, and the Dudley family for the Endowed Research Professorship. Also, Jorge Gardea-Torresdey acknowledges the LERR and STARs Retention Award (2018) of the University of Texas System

Role of Cerium Compounds in Fusarium Wilt Suppression and Growth Enhancement in Tomato (<i>Solanum lycopersicum</i>)

The use of nanoparticles in plant protection may reduce pesticide usage and contamination and increase food security. In this study, three-week-old <i>Solanum lycopersicum</i> seedlings were exposed, by root or foliar pathways, to CeO₂ nanoparticles and cerium acetate at 50 and 250 mg/L prior to transplant into sterilized soil. One week later, the soil was inoculated with the fungal pathogen <i>Fusarium oxysporum</i> f. sp. <i>lycopersici</i> (1 g/kg), and the plants were cultivated to maturity in a greenhouse. Disease severity, biomass/yield, and biochemical and physiological parameters were analyzed in harvested plants. Disease severity was significantly reduced by 250 mg/L of nano-CeO₂ and CeAc applied to the soil (53% and 35%, respectively) or foliage (57% and 41%, respectively), compared with non-treated infested controls. Overall, the findings show that nano-CeO₂ has potential to suppress Fusarium wilt and improve the chlorophyll content in tomato plants