Ferdowsi University of Mashhad Journal Of Agroecology 2008-7713 9 3 2017 09 23 Effect of Different Fertilization Systems (Chemical, Biological and Integrated( on Nitrogen and Phosphorus Concentration, Biochemical Attributes and Sepals Dry Weight of Roselle (Hibiscus sabdariffa L.) Effect of Different Fertilization Systems (Chemical, Biological and Integrated( on Nitrogen and Phosphorus Concentration, Biochemical Attributes and Sepals Dry Weight of Roselle (Hibiscus sabdariffa L.) 652 674 35948 10.22067/jag.v9i3.40529 FA Roghayeh Mhammadpour Vashvaei Department of Agronomy, Faculty of Agriculture, Zabol University, Zabol, Iran Ahmad Ghanbari Department of Agronomy, Faculty of Agriculture, Zabol University, Zabol, Iran 0000-0002-3629-136x Barat Ali Fakheri Department of Plant Breeding and Biotechnology, Faculty of Agriculture, Zabol University, Zabol, Iran Journal Article 2014 10 23 Introduction Roselle (Hibiscus sabdariffa L.) is a subtropical medicinal plant belongs to the Malvaceae family. Roselle sepals are valuable due to its therapeutic properties and culinary uses. During past decades rising cost of chemical inputs and overusing them in conventional farming have caused various environmental issues such as soil and water resources contamination, reduction in food quality production, decreasing soil fertility and biological imbalance in the soil that they impose irreparable damage to ecosystems. Sustainable agriculture which is based on the use of bio-fertilizers with the aim of eliminating or considerably reducing the use of chemical inputs is the optimal solution to overcome these problems. Abo-Baker and Gehan (2011) in their study on the effect of bio-fertilizers in combination with different rates of chemical fertilizers on growth characters, yield component and chemical constituents of roselle demonstrated that the inoculation with the mixture of bio-fertilizers combined with 50 or 100% chemical fertilizers improved, in most cases, growth characters and increased sepal yield or at least did not differ significantly from the control (full recommended dose of NPK alone). These researchers stated that applying 50% of the recommended dose of NPK plus the mixture of bio-fertilizer can save half of the quantity of chemical fertilizers, decrease the production cost and obtain high quality product. The present study was designed to investigate the effect of bio-fertilizers in combination with different doses of chemical fertilizers on the element concentrations, biochemical properties and yield of roselle to find the appropriate integration of them. Material and Methods This experiment was conducted based on a randomized complete block design with three replications, at the Research Station, University of Zabol, during growing season of 2011-2012 and 2012-2013. Experimental treatments were plant nutrition with NPK (220, 130 and 75 kg.h-1 of urea, triple super phosphate and potassium sulphate, respectively), bio-phosphate, bio-phosphate + 25% NPK, bio-phosphate + 50% NPK, bio-phosphate + 100% NPK, nitroxin, nitroxin + 25%NPK, nitroxin + 50%NPK, nitroxin + 100%NPK, nitroxin + bio-phosphate, nitroxin + biophosphate + 25% NPK, nitroxin + biophosphate + 50% NPK, nitroxin + biophosphate + 100% NPK and control (non-use of any fertilizer). Plant traits such as leaf nitrogen and protein, sepal nitrogen and protein, leaf and sepal phosphorus, sepal anthocyanin and vitamin C content, sepal acidity and sepal dry weight of roselle were measured. For statistical analysis, combined analysis of variance, Duncan’s multiple range test (DMRT), simple correlation analysis and principal component analysis were performed using SAS version 9.2 (SAS Institute Inc., Cary, NC, USA). Results and Discussion The results of combined analysis of variance of two years showed that the effects of different treatments of chemical fertilizers, bio-fertilizers and their combinations were significant (P≤0.01) for all studied traits. The highest values of all studied traits belong to the nitroxin + biophosphate + 100% NPK treatment that its difference with nitroxin + biophosphate + 50% NPK treatment was not significant, except for leaf nitrogen and protein. Dry weight of sepals had positive, strong and very significant correlation to the percentage of nitrogen, phosphorous and protein of leaves and sepals. Principal component analysis was extracted two components that justified 83.71 and 7.50% of the total variation. According to weight of the included characteristics, these two components were named to the “yield” and “quality”. Based on the diagram of principal component analysis, treatment "Nitroxin + biophosphate + 50% NPK" was achieved maximum yield and quality of roselle. Conclusion The use of 50% of the recommended dose of fertilizers with nitroxin and bio-phosphate bio-fertilizers improved plant growth and enhanced the quality and quantity of roselle sepals. This improvement may be due to the direct results of fertilizers or indirect effects through microbial contamination or activities. Therefore, with respect to the production of medicinal plants in the low-input cropping systems and to achieve sustainable agriculture and environmental protection, combinations of chemical and bio-fertilizers are recommended. Introduction Roselle (Hibiscus sabdariffa L.) is a subtropical medicinal plant belongs to the Malvaceae family. Roselle sepals are valuable due to its therapeutic properties and culinary uses. During past decades rising cost of chemical inputs and overusing them in conventional farming have caused various environmental issues such as soil and water resources contamination, reduction in food quality production, decreasing soil fertility and biological imbalance in the soil that they impose irreparable damage to ecosystems. Sustainable agriculture which is based on the use of bio-fertilizers with the aim of eliminating or considerably reducing the use of chemical inputs is the optimal solution to overcome these problems. Abo-Baker and Gehan (2011) in their study on the effect of bio-fertilizers in combination with different rates of chemical fertilizers on growth characters, yield component and chemical constituents of roselle demonstrated that the inoculation with the mixture of bio-fertilizers combined with 50 or 100% chemical fertilizers improved, in most cases, growth characters and increased sepal yield or at least did not differ significantly from the control (full recommended dose of NPK alone). These researchers stated that applying 50% of the recommended dose of NPK plus the mixture of bio-fertilizer can save half of the quantity of chemical fertilizers, decrease the production cost and obtain high quality product. The present study was designed to investigate the effect of bio-fertilizers in combination with different doses of chemical fertilizers on the element concentrations, biochemical properties and yield of roselle to find the appropriate integration of them. Material and Methods This experiment was conducted based on a randomized complete block design with three replications, at the Research Station, University of Zabol, during growing season of 2011-2012 and 2012-2013. Experimental treatments were plant nutrition with NPK (220, 130 and 75 kg.h-1 of urea, triple super phosphate and potassium sulphate, respectively), bio-phosphate, bio-phosphate + 25% NPK, bio-phosphate + 50% NPK, bio-phosphate + 100% NPK, nitroxin, nitroxin + 25%NPK, nitroxin + 50%NPK, nitroxin + 100%NPK, nitroxin + bio-phosphate, nitroxin + biophosphate + 25% NPK, nitroxin + biophosphate + 50% NPK, nitroxin + biophosphate + 100% NPK and control (non-use of any fertilizer). Plant traits such as leaf nitrogen and protein, sepal nitrogen and protein, leaf and sepal phosphorus, sepal anthocyanin and vitamin C content, sepal acidity and sepal dry weight of roselle were measured. For statistical analysis, combined analysis of variance, Duncan’s multiple range test (DMRT), simple correlation analysis and principal component analysis were performed using SAS version 9.2 (SAS Institute Inc., Cary, NC, USA). Results and Discussion The results of combined analysis of variance of two years showed that the effects of different treatments of chemical fertilizers, bio-fertilizers and their combinations were significant (P≤0.01) for all studied traits. The highest values of all studied traits belong to the nitroxin + biophosphate + 100% NPK treatment that its difference with nitroxin + biophosphate + 50% NPK treatment was not significant, except for leaf nitrogen and protein. Dry weight of sepals had positive, strong and very significant correlation to the percentage of nitrogen, phosphorous and protein of leaves and sepals. Principal component analysis was extracted two components that justified 83.71 and 7.50% of the total variation. According to weight of the included characteristics, these two components were named to the “yield” and “quality”. Based on the diagram of principal component analysis, treatment "Nitroxin + biophosphate + 50% NPK" was achieved maximum yield and quality of roselle. Conclusion The use of 50% of the recommended dose of fertilizers with nitroxin and bio-phosphate bio-fertilizers improved plant growth and enhanced the quality and quantity of roselle sepals. This improvement may be due to the direct results of fertilizers or indirect effects through microbial contamination or activities. Therefore, with respect to the production of medicinal plants in the low-input cropping systems and to achieve sustainable agriculture and environmental protection, combinations of chemical and bio-fertilizers are recommended. https://agry.um.ac.ir/article_35948_7dd701e074e9850f9d6d1b52332b0dee.pdf