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131.
The effect of aluminum (Al) ions on the germination of wheat (Triticum aestivum L.) seeds has been investigated using two varieties, one sensitive to Al (Robin) and the other relatively Al‐tolerant (Carazinho). High concentrations of Al (i.e. greater than 1 mM) were required to inhibit the growth of the emerging roots and shoots of germinating seeds of both varieties. Moreover, Al at concentrations up to 10 mM did not affect the mobilization of carbohydrate reserves in the germinating seeds. It was concluded that germinating seeds of both wheat varieties were much less sensitive to the effects of Al than were established seedlings. 相似文献
132.
The effects of nitrogen (N‐) and phosphorus (P‐) deficiency, isolatedly or in combination, on growth, nitrogenous fraction, and inorganic phosphate in xylem exudade, and photosynthesis of common bean (Phaseolus vulgaris L. cv. Negrito) were investigated. Plants were grown in nutrient solution adjusted daily to pH 5.5 and aerated continuously. Ten days after emergence mineral deficiency was imposed. Plants were then supplied with high N (7.5 mol m‐3) or low N (0.5 mol m‐3), and also with high P (0.5 mol m‐3) or low P (0.005 mol m‐3). All sampling and measurements were made 28 days after emergence. N‐ or P‐deprivation brought about large decreases in total leaf area by inhibiting the emergence of new leaves and primarily the expansion of the leaves. The specific leaf area did not change under N‐ but decreased under P‐limitation. The decreased shoot to root ratio in all deficiency treatments was a consequence of a lowering mass of above‐ground organs, especially of leaves. The content of chlorophylls declined significantly only under N‐deficiency alone; carotenoids declined under both N‐ and combined N‐ and P‐limitation. No alteration in amino acid concentration in xylem exudate occurred in plants experiencing N‐starvation, while ureides increased by 79%, and nitrate and inorganic phosphate decreased greatly. Under P‐deprivation, amino acids and nitrate in xylem sap dropped by about half; ureides were held relatively constant, and phosphate was severely depressed. Total upward translocation of N through xylem was estimated to be about 16% higher in N‐deficient plants than in plants without mineral limitation, but leaf N levels in the former were lower as compared to control plants. The net carbon (C) assimilation decreased similarly regardless of the imposed deficiency treatment. Such a decrease was mainly determined by non‐stomatal factors. In general, no additive effect between N‐ and P‐limitation on any of measured parameters was observed. 相似文献
133.
de Medeiros Erika Valente Lima Neyla Thayná de Sousa Lima José Romualdo Pinto Kedma Maria Silva da Costa Diogo Paes Franco Junior Cícero Luiz Souza Rodolfo Marcondes Silva Hammecker Claude 《Phytoparasitica》2021,49(4):713-726
Phytoparasitica - The current agricultural scenario faces a range of challenges, with phytosanitary ones being paramount. In most cases, plant diseases are treated with chemicals; however, they... 相似文献
134.
Barbosa Douglas Rafael e Silva de Oliveira José Vargas da Silva Paulo Henrique Soares Santana Mauricéa Fidelis Breda Mariana Oliveira de França Solange Maria de Miranda Vinícius Lima 《植物病害和植物保护杂志》2021,128(6):1575-1586
Journal of Plant Diseases and Protection - The recent use of essential oils has been considered an important approach in pest management programs for stored products. Regarding essential oils, it... 相似文献
135.
do Amaral Ana Cludia Tenrio de Holanda Cavalcanti Maciel Marlia Machado Alexandre Reis de Oliveira Luciana Gonalves Lima Cristiano Souza da Costa Antonio Flix de Oliveira Neiva Tinti 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):875-890
European Journal of Plant Pathology - This study aimed to evaluate the potential antagonistic role of Trichoderma in the control of Fusarium isolates belonging to the Fusarium oxysporum species... 相似文献
136.
Valetti Lucio Lima Nelson Bernardi Cazón Luis I. Crociara Clara Ortega Leandro Pastor Silvina 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):923-935
European Journal of Plant Pathology - Apple valsa canker, caused by the fungus Valsa ceratosperma, is one of the most destructive diseases of this crop. Conventional fungicide treatments are not... 相似文献
137.
138.
D.J. Moura W.T. Silva I.A. Naas Y.A. Toln K.A.O. Lima M.M. Vale 《Computers and Electronics in Agriculture》2008,64(1):11
The analysis of animal vocalization allows the interpretation of stress pattern in a non-invasive way, and it may be used to assess welfare as well as health status and social adaptation. This paper presents the development of software to monitor and analyze distinct sounds emitted by piglets correlating the noise response with levels of stress for assessing welfare. The software was developed using Delphi5. Through the component UwaveIn the sound was recorded with an electronic microphone and set to a PC hardware that registered the signal of amplitude noise intensity, expressed in decibel (dB), converting them into bytes. Fourier Transform was used to describe the sound spectrum and transform it into frequency and intensity. Validation of the software was done in a commercial swine farm using piglets from sows’ nursery. Five examples of vocalization were studied related to distinct levels of stress (fear and alertness) due to regular management procedures. The real time monitoring allowed the detection of piglet stress exposure through the surface point polynomial adjustment. The acoustic signal recorded in the software could be partitioned allowing an evaluation of the sonograph through time. 相似文献
139.
Maciel Laura Priscila Araújo Amaro de Carvalho Francisco Fernando Ramos Batista Ângela Maria Vieira Guim Adriana do Vale Maciel Michel Cardoso Daniel Barros de Lima Júnior Dorgival Morais 《Tropical animal health and production》2019,51(6):1717-1723
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the substitution of Tifton 85 hay (Cynodon spp.) with spineless cactus (Nopalea cochenillifera) on... 相似文献
140.
Effect of l‐glutamic acid supplementation on performance and nitrogen balance of broilers fed low protein diets
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R. M. Bezerra F. G. P. Costa P. E. N. Givisiez E. R. Freitas C. C. Goulart R. A. Santos J. G. Souza P. A. Brandão M. R. Lima M. L. Melo V. P. Rodrigues E. T. Nogueira D. V. G. Vieira 《Journal of animal physiology and animal nutrition》2016,100(3):590-600
The aim of this study was to evaluate the effect of protein reduction and supplementation of l ‐glutamic acid in male broiler diets. A total of 648 chicks of the Cobb 500 strain were distributed in a completely randomized design with six treatments and six replications with eighteen birds per experimental unit. The study comprised pre‐starter (1–7 days), starter (8–21 days), growth (22–35 days) and final (36–45 days) phases. The first treatment consisted of a control diet formulated according to the requirements of essential amino acids for each rearing phase. The second and third treatments had crude protein (CP) reduced by 1.8 and 3.6 percentage points (pp) in relation to the control diet respectively. In the fourth treatment, l ‐glutamic acid was added to provide the same glutamate level as the control diet, and in the last two treatments, the broilers were supplemented with 1 and 2 pp of glutamate above that of the control diet respectively. The reduction in CP decreased the performance of broilers and the supplementation of l ‐glutamic acid did not influence performance when supplied in the diets with excess of glutamate. The lowest excreted nitrogen values were observed in the control diet, and treatments 2 and 3, respectively, in comparison with treatments with the use of l ‐glutamic acid (5 and 6). Retention efficiency of nitrogen was better in the control diet and in the treatment with a reduction of 1.8 pp of CP. It was verified that the serum uric acid level decreased with the CP reduction. A reduction in CP levels of up to 21.3%, 18.8%, 18.32% and 17.57% is recommended in phases from 1 to 7, 8 to 21, 22 to 35 and at 36 to 42 days, respectively, with a level of glutamate at 5.32%, 4.73%, 4.57%, 4.38%, also in these phases. 相似文献