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Postharvest quality of yellow passion fruit produced in soil with bovine biofertilizer and nitrogen
2022
Diniz, Adriana Araujo | Cavalcante, Lourival Ferreira | de Oliveira Filho, Antonio Santana Batista | Dias, Nildo da Silva | Dantas, Tony Andreson Guedes | Campos, Vinicius Batista | do Nascimento, José Adeilson Medeiros | Dantas, Stenio Andrey Guedes
The use of soil conditioners as bovine biofertilizer associated with mineral fertilization affect the physical and physicochemical quality of passion fruit. For fruit growth, post-harvest quality is crucial for production chain development, as it is the characteristic most used by the fresh consumption market for this fruit. In this sense, an experiment was carried out to investigate the effects of doses of bovine biofertilizer in the soil with and without nitrogen fertilization in the cultivation of yellow passion fruit. A randomized block design was adopted, with three replications in a 5×2 factorial scheme, referring to five doses of liquid bovine biofertilizer (B) diluted in water (A): 0% − control (0B + 4A); 25% (1B + 3A); 50% (2B + 2A); 75% (3B + 1A); and 100% (4B + 0A) with and without nitrogen fertilization applied to the soil. Urea was the nitrogen source used in this study. A total of 10 g plant⁻¹ of N was applied monthly at 30 and 60 days after transplanting, and after that age, 20 g plant⁻¹ was applied until the end of harvest. During the final phase of production and ripening, twelve fruits were harvested from each treatment in physiological maturation for physical and physicochemical characterization. The following analyses were performed: longitudinal diameter, transversal diameter, number of seeds per fruit, peel firmness, pulp yield, fruit peel percentage, pulp pH, soluble solids content; titratable acidity and soluble solids content/titratable acidity ratio. Data underwent analysis of variance by the F test means for nitrogen were compared by Tukey’s test and means for bovine biofertilizer, by regression. Nitrogen enhances the positive effect of bovine biofertilizer on the postharvest quality of yellow passion fruit. The association of biofertilizer and nitrogen improves fruit quality in comparison to plants without these inputs, except for pulp yield and fruit peel percentage, which suffered isolated effects from the factors. High doses of biofertilizer, above 75 and 100%, reduce soluble solids content and increase titratable acidity. The bovine biofertilizer has promising effects, but it does not replace nitrogen fertilization on the postharvest quality of yellow passion fruit.
显示更多 [+] 显示较少 [-]Effects of regulated deficit irrigation applied at different growth stages of greenhouse grown tomato on substrate moisture, yield, fruit quality, and physiological traits
2021
GHANNEM, Amal | BEN AISSA, Imed | MAJDOUB, Rajouene
Given a critical water scarcity in arid and semi-arid Tunisian areas and aiming to reduce irrigation water request, it is crucial to identify and apply the best water-saving practices in these irrigated areas. Tomato is a high-water-requiring vegetable crop, thus increasing the pressure on water resources and environment. Its sustainable cultivation in such alarming conditions requires an adaptation of on-farm irrigation water-saving strategies preserving also the crop yield and leading to a fruit quality improvement. This study aimed to explore the effects of the regulated deficit irrigation (RDI) as an irrigation water-saving strategy, on yield, fruit quality, and physiological behavior of greenhouse grown potted tomato crop (Solanum lycopersicum L.) during three identified growth stages. The managed water regimes were (i) full irrigation (FI) ensuring 100% of the estimated water crop requirements, (ii) RDI1-25 and RDI1-50 ensuring respectively 75% and 50% of FI water supplies during the vegetative crop stage (stage I), (iii) RDI2–25 and RDI2–50 ensuring respectively 75% and 50% of FI water supplies from first truss blossom until first harvest (stage II), and (iv) RDI3-25 and RDI3-50 ensuring respectively 75% and 50% of FI supplies during the rest of the harvest period (stage III). The results showed that the substrate moisture vary significantly with the water deficit regime applied under different growth stages, thus providing different levels of substrate water content. Under RDI2, the tomato yield was the highest when compared with FI, RDI1, and RDI3 regimes. Indeed, saving the water by 20% under RDI2-50 reduced only 3% of tomato yield. Deficit irrigation under ripening fruit and flowering stages, mainly with 50% of water supplies shortage, resulted in higher fruit skin color, firmness, and refractometry index (°Brix) when compared to FI and RDI1. Physiological traits measurements indicated that FI exhibited the highest leaf stomatal conductance (gs) and chlorophyll index (CI) values while RDI3 exhibited the lowest gs and CI values among all the RDI treatments. Results are valuable in considering gs and CI as an efficient indicators of tomato plant water status. The results are also an important contribution to identify the second tomato growth stage as the best period that tomato plant tolerate water shortage without significant yield decrease, as well a rather fruit quality improvement. These results help to reach the challenge “more crop per drop” and can contribute to water scarcity remediation.
显示更多 [+] 显示较少 [-]Factors affecting palatability of four submerged macrophytes for grass carp Ctenopharyngodon idella
2017
Sun, Jian | Wang, Long | Ma, Lin | Min, Fenli | Huang, Tao | Zhang, Yi | Wu, Zhenbin | He, Feng
Grass carp can weaken the growth and reproductive capacity of submerged macrophytes by consuming valuable tissues, but factors affecting palatability of submerged macrophytes for grass carp rarely are considered. In this study, relative consumption rate of grass carp with regard to submerged macrophytes was in the following order: Hydrilla verticillata > Vallisneria natans > Ceratophyllum demersum > Myriophyllum spicatum. Firmness of macrophytes was in the following order: M. spicatum > C. demersum > H. verticillata = V. natans, whereas shear force was M. spicatum > C. demersum > H. verticillata > V. natans. After crude extracts of M. spicatum were combined with H. verticillata, grass carp fed on fewer macrophyte pellets that contained more plant secondary metabolites (PSMs). This indicated that structure and PSMs affected palatability of macrophytes.PSMs do not contribute to reduction in palatability through inhibition of intestinal proteinases activity, but they can cause a decrease in the abundance of Exiguobacterium, Acinetobacter-yielding proteases, lipases, and cellulose activity, which in turn can weaken the metabolic capacity of grass carp and adversely affect their growth. Thus, the disadvantages to the growth and development of grass carp caused by PSMs may drive grass carp to feed on palatable submerged macrophytes with lower PSMs.
显示更多 [+] 显示较少 [-]Causal relationship between agricultural production and carbon dioxide emissions in selected emerging economies
2018
Appiah, Kingsley | Du, Jianguo | Poku, John
Continuous threat posed by climate change caused by carbon dioxide emission has reignited global advocacy to confront its negative ramification with the greatest possible firmness. Global food security and agriculture face major challenges under climate change as a result of the potential negative effect of production and implementation of sectoral action to limit global warming. Overall, agricultural greenhouse emissions continue to rise and the analysis of superior data on emissions from farming, livestock, and fisheries can help countries identify opportunities to contemporaneously reduce emissions and address their food security. This study seeks to contribute to the recent literature by examining the causal relationship between agriculture production and carbon dioxide emissions in selected emerging economies for the period 1971 to 2013. The study, therefore, disaggregated agriculture production into crop production index and livestock production index to explicate the distinct and to find individual variable contribution to carbon dioxide emissions. By using FMOLS and DOLS, empirical results indicate that 1% increase in economic growth, crop production index, and livestock production index will cause a proportional increase in carbon dioxide emission by 17%, 28%, and 28% correspondingly, while 1% increase in energy consumption and population improves the environment of emerging economies. The direction of causality among the variables was, accordingly, examined using PMG estimator. Potentially, for emerging countries to achieve Sustainable Development Goal of ensuring zero hunger for their citizenry requires the need to alter their farming production techniques and also adopt agricultural technology method, which is more environmentally friendly.
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