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Crambe (Crambe abyssinica Hochist.) is an oilseed crop with high in euricic acid with industrial uses in production of biodiesel, nylon, plasticizers, and lubricants. Little information is available about Crambe response to phosphorus and potassium fertilization. The aim of this study was to determine the effect of phosphate (25 and 50 P2O5 kg Fed.−1) and potassium (10 and 20 K2O kg Fed.−1) fertilization on the growth characteristics and oil quality of Crambe plants. The experiment had a randomized complete block design, and it was carried out in the Experimental Station of National Research Center, Cairo, Egypt in 2019 and 2020. The results showed that the application of potassium and/or phosphorus fertilization resulted in significant increases of all vegetative growth traits, such as plant height, number of branches, fresh weight, and dry weight as well as fixed oil content. The GC analysis of fatty acid identified eight compounds in the following order of main averages; erucic acid (50.5%), elaidic acid (23.1%), Linoleic acid (10.9%), linolenic acid (6.5%), palmitic acid (4.8%), eicosanoic acid (1.9%), stearic acid (1.3%), and oleic acid (1.0%). Phosphorus and potassium had opposite effect on the main components of Crambe oil. Erucic acid increased with potassium fertilization and decreased with phosphorus fertilization. Contrast results were shown in Elaidic acid in response to potassium and phosphorus fertilizations. These results suggested the positive effect of both potassium and phosphorus fertilization on growth and oil yield of Crambe plants as well as they considered as limited factors for Erucic acid content. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the potential causes of the summer mortality syndrome affecting the earthen pond cultured Nile tilapia, Oreochromis niloticus in some Egyptian farms. A total of 100 moribund O. niloticus showing non-specific clinical signs of septicemia and mortality (30- 65%) were collected from five farms at Tolombat 7, Kafr El-Sheikh, Egypt, during June 2019. All the fish farms share the same water source and perform some bad management practices. Inadequate water quality measures were noticed in all the investigated farms. Molecular detection of tilapia lake virus (TiLV) using PCR confirmed the non-existence of the TiLV in all examined specimens. A total of 19 pathogenic bacterial isolates were obtained from moribund O. niloticus: Streptococcus agalactiae (14), Aeromonas hydrophila (3), and Vibrio cholera (2). The predominance of Streptococcus agalactiae infections points to its intense involvement in such mortalities. S. agalactiae was confirmed by 16s rRNA gene sequencing and phylogenetic analysis. The PCR detection of virulence genes showed existence of Hyl, cylE, scpB and camp genes in all S. agalactiae strains. Isolates of S. agalactiae showed variable susceptibility to the tested antibiotics with high resistance against ampicillin, amoxicillin and gentamycin. Infections were associated with several pathological alterations in naturally infected fish. The pathogenicity of S. agalactiae was confirmed in O. niloticus (90 % cumulative mortality). The data in the present study proved that the tilapia summer mortality syndrome is multifactorial. Thus, good managemental practices and water quality measures are recommended to minimize fish mortality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)