Unfertilized Plants Research Articles

The effect of seaweed fertilisation on sulfur isotope ratios (δ34S) and grain size in barley: implications for agronomy and archaeological research

IntroductionStable sulfur isotope ratios (δ34S) in bone collagen are often employed to study the consumption of marine and freshwater fish, wetland grazing, marine foraging patterns, and the possible geographic origins of food sources. However, a recent small-scale crop experiment showed that biofertilisation with seaweed can elevate δ34S in Celtic beans by ca. 10 ‰. Consumption of this food could erroneously suggest a marine diet and therefore has important implications for the reconstruction of past diets and dietary origins. However, limited research has so far been undertaken on cereals.MethodsTo address this issue, a large-scale field trial was undertaken on the Orkney Islands, whereby bere barley (a Scottish landrace, Hordeum vulgare L.) was biofertilised with seaweed at different dosages (25 t/ha, 50 t/ha), with a mineral NPK fertiliser, and left unfertilised as a control.ResultsThe total barley biomass yield was higher and barley grains were enlarged following all fertilisation treatments compared to the control barley. Barley grain and straw from seaweed-fertilised crops had more elevated δ34S values by around 2–3 ‰ compared to unfertilised plants, while the NPK-fertilised grains and plants had δ34S values 1 ‰ lower.DiscussionThese results confirm previous hypotheses that seaweed fertilisation can elevate cereal δ34S values. The comparatively small δ34S difference between control and seaweed fertilised crops in this field trial is likely due to background elevated δ34S values in the soil (+12.7 ‰), which in turn may be due to long-term exposure to oceanic-influenced rain and sea spray and/or possible historical application of seaweed, or the underlying bedrock composition. The results of this study show that seaweed fertilisation can increase barley grain sizes and δ34S values, and thus should be considered when reconstructing land management and dietary practices in the archaeological record.

Circular Utilization of Coffee Grounds as a Bio-Nutrient through Microbial Transformation for Leafy Vegetables

This study explores the production of bio-nutrients from bioactive compound-rich spent coffee grounds (SCG) and biochar (BC) through composting after inoculation with a biological agent and its impact on the growth performance of garden cress and spinach. The SCG was composted with six doses of BC (0, 5, 10, 15, 20, and 25%). The compost with 10% BC exhibited the best maturity, humification, and phytotoxicity index values of dissolved organic carbon (DOC), humification index (E4/E6), and germination index (GI). A metagenome analysis showed that compost starter enhanced the bacterial community’s relative abundance, richness, and diversity in SCG and BC treatments. This improvement included increased Patescibacteria, which can break down noxious phenolic compounds found in SCG and BC. The BC enriched the compost with phosphorus and potassium while preserving the nitrogen. In plant growth experiments, the total chlorophyll content in compost-treated garden cress and spinach was 2.47 and 4.88 mg g−1, respectively, which was significantly greater (p ≤ 0.05) than in unfertilized plants and similar to the plants treated with traditional fertilizer. Overall, the results show that the compost of SCG + BC was well-suited for promoting the growth of garden cress and spinach, providing adequate nutrients as a fertilizer for these leafy vegetables.

Effect of Winter Sowing and Different Fertilizer Sources on Physiological Parameters and Yield Components of Dragon’s Head (Lallemantia iberica Fisch. & C.A.Mey.)

The effects of autumn sowing and chemical, organic, and biological fertilizer sources were explored on yield components and physiological traits of dragon’s head (Lallemantia iberica Fisch. & C.A.Mey). The study was conducted as a factorial experiment based on a randomized complete block design with three replications in a field experiment in the 2017-2018 crop year. The fertilizer treatments included organic fertilizers (vermicompost, manure, and humic acid), biofertilizer (Thiobacillus mixed with sulfur), chemical fertilizer (macro NPK), and control (no fertilizer). The studied traits included seed yield per ha, harvest index, biological yield per ha, chlorophyll a, chlorophyll b, carotenoid, proline, and dissolved carbohydrate. The results of the comparison of the means revealed that the winter sowing outperformed the spring sowing evidently and increased traits like seed yield per ha, biological yield per ha, and harvest index significantly. The fertilization of the plants in both sowing seasons, especially in the winter sowing, increased seed yield per ha, biological yield per ha, and harvest index so that the vermicompost-fertilized winter-sown plants produced the highest seed yield per ha (0.91 g), whereas the application of manure was related to the highest harvest index in the winter sowing (27.9%). The highest biological yield (8797 kg ha-1) was related to the treatment of Thiobacillus of the winter-sown plants. Proline content was higher in the spring sowing plants, and the control treatment in the spring sowing had the highest proline content (0.120 mg g-1). Concerning dissolved carbohydrates, the spring sowing and the unfertilized plants had the highest content (20.3 mg g-1). On the other hand, chlorophyll a, chlorophyll b, and carotenoid were higher in the treatments of Thiobacillus and vermicompost, which resulted in achieving higher yields due to the increase in photosynthesis rate. According to the results, the winter sowing of the dragon’s head in the Azerbaijan region of Iran and the use of Thiobacillus and vermicompost could be recommended for obtaining plants with optimum quality parameters.

Host Plants and Fertilization Mediated Life History of American Serpentine Leaf Miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae).

Herbivorous insects depend on the host plant to optimize their overall reproductive success, and balanced fertilization may alter the plant's quality against herbivory. Life history traits of the Liriomyza trifolii (Burgess) were determined under laboratory conditions using either unfertilized and fertilized plants of bean [Phaseolus vulgaris L. (Fabaceae)], chrysanthemum [Chrysanthemum × morifolium (Asteraceae)], potato [Solanum tuberosum (Solanaceae)], bell pepper [Capsicum annuum (Solanaceae)], and tomato [Solanum lycopersicum (Solanaceae)]. Results indicated that L. trifolii completed development on all studied unfertilized and fertilized plants. Nevertheless, a higher performance of the leaf miner was observed on bean and bell pepper plants compared to the other plants. Furthermore, there was an interaction of the host plant and fertilization with Calcium Aria or Sitam negatively affecting the fitness-related traits of the leaf miner. Application of these fertilizers resulted in delayed immature development of L. trifolii, decreased survival rate, and reduced adult longevity and fecundity. The activity of cinnamyl alcohol dehydrogenase (CAD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL) enzymes, as well as phenolic, flavonoid, and lignin content were higher in Calcium Aria + Sitam fertilized plants, intermediate in Calcium Aria and Sitam treated plants, and the lower in unfertilized plants. The development and survival of L. trifolii on different host plants, considering fertilization options, become important for deploying cultural control practices against this important pest species.

Soil Nitrogen Fertility Influences the Growth and Yield of American Elderberry but Is Less Impactful than Genotype and Environment on Other Horticultural Characteristics

A long-term horticultural experiment was conducted at two geographically distinct sites in southern Missouri in 2011–15 to study the response of American elderberry [Sambucus nigra (L.) subsp. canadensis (L.) Bolli] to various soil nitrogen (N) fertilizer levels. Three commercially available elderberry cultivars (‘Adams II’, ‘Bob Gordon’, and ‘Wyldewood’) were used. The three cultivars were each assigned to 16 of 48 four-plant plots in a completely randomized manner at each site. Four replications of four N fertilizer treatments (0, 56, 112, 169 kg⋅ha−1 N) were randomly assigned to each cultivar’s plots and applied for 4 years (2012–15). Fruit yields, plant growth, phenology, and pest incidence were determined each year. Fruit quality was assessed by analyzing basic juice characteristics as well as organic acids, carbohydrates, anthocyanins, and polyphenols from 2012–14 samples. Leaf tissue analysis determined the plants’ mineral contents in 2012–14. Most factors evaluated were significantly affected by site, year, and cultivar, whereas the effects of N fertilizer treatment were less definitive. Fruit yields and plant growth increased with increasing N levels. For example, plants fertilized with 0, 56, 112, and 169 kg⋅ha−1 N produced 123, 137, 155, and 161 fruiting cymes per plot (5.8 m2), respectively. The eriophyid mite incidence was higher on fertilized plants, but other pests were not influenced by the N treatment. Basic fruit juice characteristics (soluble solids, pH, titratable acidity, polyphenols) were not influenced by the N treatment, whereas total anthocyanins were statistically higher in unfertilized plants. Levels of organic acids and carbohydrates in juice varied statistically among N treatments, but patterns were difficult to discern. Leaf N concentrations were correlated with N fertilizer levels—2.75% N with the highest fertilizer level compared with 2.55% N in unfertilized plants. Leaf levels of most other macronutrients varied, but consistent patterns did not emerge, and none of the micronutrients was different among N treatments. Although elderberry plants responded positively to increased N fertilizer levels in terms of plant growth and fruit yield, genetics (cultivar) and environment (site, year) were more influential on most other experimental factors evaluated.

Tales unraveled through threads: Exploring the influence of natural dyes on the carbon and nitrogen isotope ratios of wool fibers from historical rugs

EA-IRMS has been used to find isotope ratio patterns as a way of ascertaining the provenance of materials in several fields of science. In this work, EA-IRMS analysis of δ13C and δ15N was used to study historical rugs’ raw materials. The influence of chromophores in the isotope ratio of wool was studied by dyeing contemporary wool with traditional dyestuff and analyzing it by EA-IRMS. Additionally, aiming towards provenance determination, historical rugs’ samples were analyzed. In general, δ13C and δ15N of contemporary dyed wool showed no significant difference between samples (P > 0.05) which rebutted the hypothesis that chromophore isotope ratios influence those of wool. Furthermore, δ13C and δ15N of both contemporary and historical wool samples were indicative of sheep diets comprised exclusively of C3 unfertilized plants. Exception was made for one rug whose δ15N values were compatible with organically fertilized plants. Particularly, δ13C and δ15N ratios of historical samples showed significant inter-rugs differences (P < 0.05) which could evidence meteorological changes over the years. Intra-rug differences detected in only one of the three rugs studied could be linked to changes in sheep diet and pastures management practices due to drought conditions. In sum, this work's results showed that is possible to use EA-IRMS analysis of δ13C and δ15N to study dyed wool without chromophore interference.

Добив и качество на тютюн Виржиния в зависимост от генотипа и агротехничски практики

The effects of three N rates (0, 20 and 40 kg N ha-1) and time of topping (topping at early flowering and topping at full flowering) on yield and quality (percentage of first, second and third grade dried tobacco, and chemical composition) of Virginia tobacco genotypes (Virginia 0514, Hybrid 33, Hybrid 27) were studied in field experiment in 2015-2016. The experimental design was a randomized complete block replicated three times. The most important factor that affects leaf yield was N rate. Genotype differences and time of topping also had a significant effect on the yield. The application of 20 and 40 kg N ha-1 improved the leaf yield by 12.6%, and 17.8%, respectively, in comparison with unfertilized plants. When tobacco was topped at early flowering stage, the yields of the different genotypes increased by 4.3%-10.1% compared to the topping at full flowering. Nitrogen fertilization and topping had almost the same effect on the quality of the tobacco (as determined by the percentage of first grade dried tobacco). The genotype effect was weaker but also statistically significant. The quantity of the first class was also determined by the interaction of topping and nitrogen rate. Topping at early flowering increased the concentrations of nicotine and total nitrogen in tobacco. The reducing sugars/nicotine ratio was higher, and in this case more favorable, when tobacco plants were topped at full flowering stage. Nicotine content (2.33%-3.53%) increased when the rate of nitrogen increased. There was a negative relationship between increasing N levels and reducing sugars content.

Slow-release hydroxyapatite fertilizer from crab shells waste for sustainable crop production

Slow-release fertilizer (SRF) is an alternative to more efficient fertilization. SRF can gradually release nutrients in fertilizer, hence the nutrients needed by for the plant growth will be available for a more extended period. In this study, SRF was made by mixing single fertilizer (urea and ammonium sulfate) with hydroxyapatite particles from crab shell biowaste. Slow-release hydroxyapatite fertilizer synthesized with a ratio between single fertilizer and hydroxyapatite powder of 6:1, then applied to grow Capsicum annuum pepper plants. The result showed that applying hybrid fertilizer affected the growth and yield of Capsicum annuum pepper plant, by enhancement of plant height up to 150 %, stem diameter up to 168 %, number of leaves up to 167 %, number of fruits up to 449 %, fruit diameter up to 200 % and fruit weight up to 234 %, compared with unfertilized plant. The SRF fertilization slightly affect the soil acidity, however the pH changed showed no effect to the plant growth. The use of HA as fertilizer promotes more sustainable crop production, by efficient nutrient uptake and utilization calcium-rich biowaste.

Response of soil fertilization and insect pollination on okra production: Prospect for optimizing underutilized crop management

The contribution of wild pollinators and input-based management practices during production of underutilized crop such as okra are pivotal for enhancing sustainable food production. Information on the beneficial role of insect pollination on okra and soil management practices is scanty, details on their specific response at each location are required to evaluate the potential of these sustainable farming practices. We examined the effects of insect pollination (pollinator-exclusive approach) and soil fertilization (fertilizer application) on okra production, using a factorial experiment arranged in a split-plot design with four replications. The complementary benefits of insect pollination and soil fertilization were evident in yield parameters such as seed weight, fruit nodes and the number of pod/plants. A substantial increase in yield began in trials with 50 % pollination rate under minimal soil fertilization. The increase in okra seed weight was (42 %) and (36 %) higher in optimal fertilized plants with 100 % and 50 % pollination rates than in non-pollinated and unfertilized plants. The similarities in yield observed from optimal fertilized soil with 50 % and 100 % pollination rates, imply that optimal soil fertilization can alleviate the yield reduction in okra due to moderate decline in pollinators exposure. Among the important okra pollinators were bees, flies, wasps, beetles and lepidopterans. Bees provided most pollination services, while other wild pollinator groups made less frequent but still give significant contributions. Thus, yield maximization requires an improvement in both agroecosystem services and soil management practices. Adequate pollinator visitation improves okra productivity in high insect-pollinated cropping systems.

The impact of maize irrigation intervals and potassium fertiliser rates on mealybug populations, vegetative growth, and resulting yield

The mealybug, Phenacoccus solenopsis (Hemiptera: Coccomorpha: Pseudococcidae), is one of the main pests attacking maize plants in Egypt. Field trials were carried out in the maize field to assess the influence of irrigation periods and potassium fertiliser rates on the mealybug ( P. solenopsis) population estimates, vegetative growth, resulting yield, and its components for the maize cultivar (‘Single-Hybrid 168 Yellow’) in the Luxor Governorate, Egypt. Results revealed that unfertilised plants irrigated every seven days had higher pest population densities than other treatments over the two seasons. The fertilised treatments at 114 kg K 2O∙ha –1 that received water every 10 days had the smallest population of P. solenopsis in every season. Data during the two seasons (2021 and 2022) revealed that the maize to which potassium fertiliser was added by 114 kg K 2O∙ha –1 and irrigated every 10 days had vegetative growth (plant height, diameter, and number of green leaves per plant), yield and its components (average ear length, ear weight, number of grains per ear, weight of 1000 grains, and grain yield) significantly increased as compared to those of the plants that were irrigated every 7 days and without adding fertiliser. A higher dose of potassium fertiliser reduces the infestation of P. solenopsis but causes an increment of maize vegetative growth. This affects the final yield. This information aids farmers in comprehending the good agronomic techniques of maize plants to decrease the infestation of mealybugs and increase the yield.

Soil water dynamics and biomass production of young rooibos (Aspalathus linearis) plants

Rooibos (Aspalathus linearis) is endemic to certain regions of the Western- and Northern Cape of South Africa, where it is also commercially grown. Being low-rainfall regions, information on the soil water balance of rooibos is essential, but such data is limited. Consequently, the effect of inorganic fertilisation and soil depth on soil water dynamics in a young rooibos plantation at Nardouwsberg, Western Cape were studied. Soil water content of plots planted to unfertilised and fertilised plants as well as that of bare soil were determined over the duration of the 2016/17 season. All treatments were replicated on shallow and deep soils sites and plant growth was determined at the end of the season. At the end of the study, the profile soil water content and evapotranspiration of the bare and planted plots were similar which prove that fallowing (water harvesting) is not an option in the sandy soils of this region. With the exception of the 20−30 cm root zone of the planted plots at the deep site, the water content decreased to levels below the permanent wilting point in the soil profile during summer. It was concluded that rooibos plants could survive through an adapted root system. A further survival method was proposed, involving moisture moved through evaporation from the deeper soil layers into the drying-front in the ~ 10−30 cm soil layer where a condensation-evaporation cycle enables rooibos to harvest small amounts of water. The highest shoot biomass with the longest taproot resulted from the unfertilised treatment on the deep soil thanks to higher soil water content, whereas the shoot and root biomass of the fertilised treatment at both sites were low due to high P soil concentration. This study revealed that unfertilised plants on deeper soils result in higher rooibos production under drought conditions.

Perennial Ryegrass (Lolium perenne L.) Response to Different Forms of Sulfur Fertilizers

The aim of the study was to compare sulfate fertilizers and mixtures of elemental sulfur (S0) and sulfate in terms of yield and nitrogen (N) and sulfur (S) status in perennial ryegrass. Mixtures of sulfate and S0 can reduce the consumption of sulfate alone. The plants were grown in soil cultures. The plants were supplemented with S0, K2SO4, MgSO4, and (NH4)SO4 or a mixture of these salts with So. Two sulfur doses were applied and the ryegrass was harvested three times. Fresh and dry weights of each swath, the N and S content, and their uptake were determined. The total fresh yield of sulfur-fertilized plants was 25 to 94% higher compared to unfertilized plants. The increases in dry matter were even more significant. Fertilizers, being a mixture of S0 and sulfate, showed the same efficiency as those containing sulfate alone. Sulfur fertilization resulted in a higher S content and its uptake, lowered N concentration in second and third swatch, and a decrease in total N uptake. In conclusion, to achieve high crop yields, soil sulfur deficiency should be corrected and fertilizers that are the mixture of elemental sulfur and sulfate are a beneficial and effective approach.

Nutrient supply and accessibility in plants: effect of protein and carbohydrates on Australian plague locust (Chortoicetes terminifera) preference and performance.

In contrast to predictions from nitrogen limitation theory, recent studies have shown that herbivorous migratory insects tend to be carbohydrate (not protein) limited, likely due to increased energy demands, leading them to preferentially feed on high carbohydrate plants. However, additional factors such as mechanical and chemical defenses can also influence host plant choice and nutrient accessibility. In this study, we investigated the effects of plant protein and carbohydrate availability on plant selection and performance for a migratory generalist herbivore, the Australian plague locust, Chortoicetes terminifera. We manipulated the protein and carbohydrate content of seedling wheat (Triticum aestivum L.) by increasing the protein:carbohydrate ratio using nitrogen (N) fertilizer, and manipulated the physical structure of the plants by grinding and breaking down cell walls after drying the plants. Using a full factorial design, we ran both choice and no-choice experiments to measure preference and performance. We confirmed locust preference for plants with a lower protein-carbohydrate ratio (unfertilized plants). Unlike previous studies with mature wild grass species, we found that intact plants supported better performance than dried and ground plants, suggesting that cell wall removal may only improve performance for tougher or more carbohydrate-rich plants. These results add to the growing body of evidence suggesting that several migratory herbivorous species perform better on plants with a lower protein:carbohydrate ratio.

Polyphosphate fertilizer impacts the enzymatic and non-enzymatic antioxidant capacity of wheat plants grown under salinity

By 2050, the predicted global population is set to reach 9.6 billion highlighting the urgent need to increase crop productivity to meet the growing demand for food. This is becoming increasingly challenging when soils are saline and/or deficient in phosphorus (P). The synergic effect of P deficiency and salinity causes a series of secondary stresses including oxidative stress. Reactive Oxygen Species (ROS) production and oxidative damage in plants caused either by P limitation or by salt stress may restrict the overall plant performances leading to a decline in crop yield. However, the P application in adequate forms and doses could positively impact the growth of plants and enhances their tolerance to salinity. In our investigation, we evaluated the effect of different P fertilizers forms (Ortho-A, Ortho-B and Poly-B) and increasing P rates (0, 30 and 45 ppm) on the plant's antioxidant system and P uptake of durum wheat (Karim cultivar) grown under salinity (EC = 3.003 dS/m). Our results demonstrated that salinity caused a series of variations in the antioxidant capacity of wheat plants, at both, enzymatic and non-enzymatic levels. Remarkably, a strong correlation was observed between P uptake, biomass, various antioxidant system parameters and P rates and sources. Soluble P fertilizers considerably enhanced the total plant performances under salt stress compared with control plants grown under salinity and P deficiency (C+). Indeed, salt-stressed and fertilized plants exhibited a robust antioxidant system revealed by the increase in enzymatic activities of Catalase (CAT) and Ascorbate peroxidase (APX) and a significant accumulation of Proline, total polyphenols content (TPC) and soluble sugars (SS) as well as increased biomass, Chlorophyll content (CCI), leaf protein content and P uptake compared to unfertilized plants. Compared to OrthoP fertilizers at 45 ppm P, Poly-B fertilizer showed significant positive responses at 30 ppm P where the increase reached + 18.2% in protein content, + 156.8% in shoot biomass, + 93% in CCI, + 84% in shoot P content, + 51% in CAT activity, + 79% in APX activity, + 93% in TPC and + 40% in SS compared to C+. This implies that PolyP fertilizers might be an alternative for the suitable management of phosphorus fertilization under salinity.

Integrated use of polyphosphate and P-solubilizing bacteria enhanced P use efficiency and growth performance of durum wheat.

Coupling phosphate-solubilizing bacteria (PSB) with P fertilizers, including polyphosphates (PolyP), was reported as eco-efficient approach to enhance P use efficiency. Although PSB have been recently reported to hydrolyze PolyP, the plant growth promoting mechanisms of PolyP-PSB co-application were not yet uncovered. This study aims to evaluate the effect of a PSB consortium (PSBCs) on growth, P use efficiency (PUE), and wheat yield parameters under PolyP (PolyB) application. Co-application of PolyB-PSBCs significantly enhanced wheat growth at 75 days after sowing (DAS) compared to 30 DAS. A significant increase in shoot dry biomass (47%), shoot inorganic P content (222%), PUE (91%), and root P absorption efficiency (RPAE, 99%) was noted compared to unfertilized plants. Similarly, the PolyB-PSBCs co-application enhanced morphological root traits at 30 DAS, while acid phosphatase activities (root and rhizosphere), RPAE, and PUE were significantly increased at 75 DAS. The improved wheat P acquisition could be attributed to a lower investment in root biomass production, and significant induction of acid phosphatase activity in roots and rhizosphere soil under PolyB-PSBCs co-application. Consequently, the PolyB-PSBCs co-application significantly improved aboveground performance, which is reflected by increased shoot nutrient contents (P 300%, K 65%), dry weight (54%), and number (50%) of spikes. Altogether, this study provides relevant evidence that co-application of PolyP-PSBCs can be an integrated and environmentally preferred P fertilization approach owing to the dual effects of PolyP and PSBCs on wheat PUE.

Production of Beauregard Sweet Potato in vertical farming under different fertilization technologies

Ipomoea batatas, popularly known as sweet potato, is a species of the Convolvulaceae family, with probable origin between Mexico and northern South America. Among the genotypes with economic potential, the biofortified cultivar Beauregard (Ipomoea batatas) stands out due to its rusticity and easy handling. Controlled-release fertilizers were mostly used in studies developed in other countries, and their study being necessary in Brazilian soil and climatic conditions. This study aimed to evaluate the development of Beauregard biofortified cultivar, submitted to different fertilization technologies in vertical farming system. The plantlets received different doses of controlled-release fertilizer: 0.0 (control); 30; 60; 90; 120g and a dose of 40g per pit of NPK 13-13-28 of ready solubility. At 180 days, biometric and production parameter data were collected and submitted to regression analysis and variance analysis followed by the Scott-Knott test for mean separation. The application of controlled-release fertilizer showed a positive effect on the production of the studied cultivar, favoring the performance of the plants and promoting the increase especially in height, length of branches and number of leaves. The base application of controlled-release fertilizer at a dose of 30g per plant and traditional NPK fertilizer at a dose of 40g per plant promote higher yields of dry mass of shoots and root when compared to unfertilized plants in the cultivation of sweet potatoes in vertical farming.

Effect of Organic and Bio-Fertilization on Fruit Yield, Bioactive Constituents, and Estragole Content in Fennel Fruits

Fennel fruits (Foeniculum vulgare Mill.) represent one of the plant-based natural spices. This study aims to improve the fruit yield and essential oil (EO) quality by reducing the undesirable component, estragole, under different fertilizer treatments. The fertilizers included chemical nitrogen, phosphorus, and potassium (NPK), and also the organic additive, rabbit manure (RM). For bio-fertilization, plants were inoculated with a mixture of N-fixing bacteria, and P- and K-solubilizing bacteria with/without vesicular-arbuscular mycorrhizal fungi. The results showed that fruit and EO yield parameters, total phenolic content (TPC), total flavonoid content (TFC), and DPPH scavenging activity of fruit extracts were enhanced by fertilizer treatments in both growing seasons. NPK at 150% of the recommended dose (NPK150) and RM at 60 m3/fed (RM60) recorded the highest values of plant height, umbel number/plant, 100-fruit weight, fruit yield, chlorophyll, carbohydrates, N and P content, EO content, and yield. TPC and TFC were enhanced by using biological fertilizers. DPPH scavenging activity was higher in organically and biologically fertilized fennel. The GC-MS analyses of EO revealed higher contents of the desirable trans-anethole in the organically and chemically fertilized fennel. However, the highest proportion of estragole, the undesirable compound, was recorded for NPK150 and unfertilized plants. On the contrary, increases in the EO content and yield of fennel fruits were achieved by RM along with a reduction in estragole, enhancement in trans-anethole, and increments in other favorable compounds such as fenchone and limonene. In addition, the inhibition of estragole formation was recorded with bio-fertilizers, which also increased the trans-anethole content. Furthermore, the trans-anethole/estragole ratio was significantly higher with the application of organic and bio-fertilization. Hence, organic and bio-fertilizer resources can produce high-quality fennel fruit and EO. The reduction in the use of chemical fertilizers can help to reduce environmental pollution.

Evaluation of the Effect of Variable Fertilization Formulas on the Severity of Viral Diseases of Five Tomato Cultivars in Southern Togo Using a Linear Model

One of the solution approaches to tomato viral diseases is undoubtedly the cultivation of tolerant cultivars. However, the environment in which these tomatoes are grown must allow them to favorably express their resistance to viruses. The soil nutrients brought or not are part of this environment. The objective of this study is to find ways and means from fertilization to create favorable conditions for the resistance of tomato cultivars to viruses. To do this, two experiments were conducted at the agronomic experiment station of the University of Lomé during the long rainy seasons of 2019 and 2020 under five tomato cultivars (Caraïbo, Mongal-F1, Petomech, Tropimech and Adakamenou) under the conditions of five fertilization formulas, T0 (0 fertilizer), T1 (200 kg NPK 15 15 15 and 100 kg urea 46% ha-1), T2 (10 t cattle manure ha-1), T3 [ (T1+T2)/2] and T4 (300 kg NPK 15 15 15, 67 kg urea 46% ha-1 and 5 t ha-1 of cattle manure). The split-plot design was used where the fertilizers were in main plots and the cultivars in sub-plots. The linear regression of virus severities observed during the experiment according to a rating scale from 1 to 5 made it possible to describe the behavior of the cultivars. The regression's lines slopes varied from 10.55% to 43.72% under the unfertilized plants; from 2.92% to 12.4% under fertilized Caraïbo plants; from 6.70% to 9.80% under fertilized Mongal-F1 plants; from 26.77% to 49.46% under fertilized Petomech plants; from 48.77% to 63.55% under fertilized Tropimech plants and from 5.22% to 16.76% under fertilized Adakamenou plants. It follows that the behavior of a tomato cultivar with respect to viruses differs according to the fertilization formula that has been given to it and that taking fertilization into account would be essential in the management plans for tomato viruses.

Response of Maize-Green Gram Intercropping to Manure and Mineral Fertilizers in Post Mined Soils

Mining is an important economic activity globally that is associated with provision of raw materials, industrial growth, employment creation as well as degradation of natural ecosystems and agricultural land. A study was conducted at Base Titanium limited mining company to evaluate the response of maize-green intercrop to farmyard manure and mineral fertilizer in post mined soils. Treatments were sole manure, sole inorganic fertilizer, manure + inorganic fertilizer and unfertilized (control) laid down in randomised complete block design (RCBD) and replicated three times. Data collected included soil nutrients before and after cropping, maize and green grams growth and yield parameters. Obtained data was subjected to analysis of variance using genstat software and means separated using Fisher's LSD. The post mined soils were slightly acidic with optimal levels of Ca, Mg, Mn and Zn, Low levels of P,K, S, B,Cu, CEC, TN and organic matter. After two cropping seasons, S and TN was observed to increase in all treatments, while Ca, Mg, Mn, B and Zn decreased in all treatments. Combined manure and fertilizer application increased average maize plant height, stem circumference and LAI by 38%, 34%, 60% respectively and ears per plant, cob length, grains per cob, grain yield and dry matter weight by 57%, 13%, 47%, 31% and 35% respectively compared to unfertilized plants. Green grams growth and yield in the intercropping system was however not significant after either manure and/or fertilizer application. Although the findings showed that manures and fertilizers application improved nutrient availability in this post mined soils, further research is required to ascertain maize–green gram intercrop, optimal establishment time, spacing, fertilizer and manure rates that can provide optimal intercrop yield as well as soil regeneration.

Nutrient and Nutraceutical Quality of Rocket as a Function of Greenhouse Cover Film, Nitrogen Dose and Biostimulant Application

The nutrient and nutraceutical quality of greenhouse wild rocket is strongly influenced by the light environment and nitrogen fertilization. We investigated the effects of two cover materials, a diffuse light film (Film1) and a traditional clear film (Film2), and three nitrogen regimes, no N supply (N0) and sub-optimal (N1) and optimal (N2) doses, also in combination with a biostimulant (Stimolo Mo), on the mineral composition, antioxidant properties and chlorophyll and carotenoid content of rocket plants grown in the autumn–spring cycle. The leaf concentration of most of the minerals was higher under Film1 compared to Film2. In general, K, Ca, Mg and Na were higher, and S was lower in the presence of N supply, and the addition of the biostimulant promoted the mineral uptake. Under Film1, the hydrophilic antioxidant activity (HAA) was higher in some harvests, and the ABTS antioxidant activity (ABTS AA) in the first one, while always lower afterward, than under Film2. Nitrogen fertilization did not affect the antioxidant activity, while it reduced the content of total phenols and ascorbic acid. The biostimulant application increased ABTS AA at the optimal N dose and reduced total phenols in unfertilized plants. Both the diffuse light and the N supply inhibited the synthesis of ascorbic acid, while N fertilization and the biostimulant promoted the synthesis of chlorophylls. The experimental treatments exerted variable effects over time and significant interactions with the harvest period were found for many of the investigated parameters.