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Copyright of Výživa a Potraviny is the property of Spolecnost pro Vyzivu 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.)

During the last decades, methods of halo conditioning have been developed to increase the tolerance to salinity in glucophyta crops. Some experiments have carried out the application of hydrogen peroxide (HO), in support to the modification of cell tolerance in saline medium. The first objective of this study was to evaluate the effects of the incorporation of HO in salinity tolerance development of the aquatic lily ( Eichhornia crassipes). Results showed that the incorporation of 0.03 % HO salinity tolerance developed in salt concentrations similar to seawater. Saline stress tolerance in aquatic lily was shown by the excretion of salts in its leaves; this process helped also in removing salt from seawater. At the same time, the reproduction of the lily is intimately linked to the content of nitrogen (N) and phosphorus (P) (nutrients) in water. This reason is important to control the concentrations of these elements in the water. This will allow maintaining a control in the dissemination of the lily. Considering the mentioned above, the second objective was to continue development of the adaptation of the aquatic lily in seawater, using HO and the required amount of nutrients. This paper points out the importance of considering a biological process for the treatments in the desalination of seawater, making the process more sustainable. [ABSTRACT FROM AUTHOR]

(Heliocarpus popayanensis Kunth (Malvaceae) tolera a hipoxia do substrato?) A espécie Heliocarpus popayanensis é muito utilizada em recomposição florística de áreas degradadas, cujo solo pode apresentar hipoxia. Considerando esses aspectos, este trabalhovisou avaliar resposta desta espécie ao alagamento. Indivíduos com 70 dias foram submetidos a substrato drenado(D) e alagado (A) por 30 e 60 dias e a alagado, 30 dias, e a drenado mais 30 dias (A/D). Foram determinados os comprimentos da raiz principal e do caule, a área foliar e o número de folhas, a biomassa e a taxa de crescimento relativo (TCR) de raízes, caules e folhas e o conteúdo nutricional das folhas. Até 60 dias de alagamento houve redução percentual média na biomassa (38%), na TCR (77%) e área foliar (24%), além de redução no diâmetro do caule e da raiz (70%) e na lignificação de célulasfloemáticas. Nenhuma alteração anatômica ocorreu nas folhas, mas houve redução na concentração dos nutrientes N, P, K, Fe, Cu e B. Portanto, em condições experimentais, Heliocarpus popayanensis sobrevive a períodos de alagamento, provavelmente pelas alteraçõesmorfoanatômicas. A raridade desta espécie em área alagável deve estar relacionada com outras etapas do ciclo de vida, como germinação das sementes ou estabelecimento de plântulas e juvenis em competição com outras espécies.The species Heliocarpus popayanensis is used on floristic recomposition of degraded areas, wich’s soil might present hypoxy. Considering these aspects, this studies evaluates this species answers to flooding. Young plants were submitted to drained and flooded substract for 30 and 60 days, then flooded for 30 days and then drained for more 30 days. Main root and stem length, area and number of leaves, biomass and relative growth rate of roots, stems and leaves and the nutritional content of leaves were determined. Until 60 days of flooding there was a percentual reduction in biomass (38%), in RGR (77%) and in the area of leaves, including reduction in root and stem’s diameter (70%), and in the lignification of floematic cells. There was no anatomic alteration in leaves, but there wasreduction of nutrients concentration (N, P, K, Fe, Cu, B). Therefore, young plants of the species Heliocarpus popayanensis survive to the flooding period considered above, probably due to anatomical and morphologic alterations. The rarity of this species in flooded area isprobably related to other stages of the life cycle, such as seeds germination or competition with other species in the environment.

Estudou-se a composição de macro e micronutrientes em folhas e caule do ramo produtivo da lichieira 'Bengal' no período de julho de 1997 a setembro de 1998. Foram amostrados, quinzenal ou semanalmente, ramos do último surto de crescimento anterior a julho de 1997. A composição mineral de folhas e caule variou com o avanço da idade ocorrendo tendências de redução das quantidades de N, P, K, S, Fe, Cu, Zn e Mn nas folhas do início da amostragem até o final do florescimento. Do mesmo modo, o conteúdo foliar de todos os nutrientes, à exceção de Ca, Mg, Fe e Mn, reduziu-se nas folhas no período de emissão de novo surto de crescimento ocorrido a partir de fevereiro de 1998, após a colheita dos frutos. Isso indica a translocação daqueles nutrientes para os novos surtos de crescimento, embora a queda de folhas também possa estar contribuindo para reduzir os conteúdos de minerais. No caule, houve aumento no conteúdo de todos os nutrientes durante o ano, à exceção do período de desenvolvimento dos frutos, em que houve redução dos conteúdos de N, P, K, Mg e Cu.Macro and micronutrients composition of leaves and stem of bearing branches of 'Bengal' litchi was studied from July/97 to September/98. Samples consisted of branches of the last vegetative flush before July/97, which were taken every one or two weeks. Mineral composition of leaves and stem changed with the age. In leaves, the amounts of N, P, K, Fe, Cu, Zn and Mn tended to decrease from the beginning of the sampling period until the end of flowering. In the same way, leaf contents of all nutrients, but Ca, Mg, Fe and Mn, decreased during the new vegetative flush emission, between February and March of 1998, one month after fruit harvest. This indicates the translocation of these nutrients to the new vegetative flush, although leaf fall could have contributed to reduce nutrients amounts. In the stem, the amounts of all nutrients tended to increase during the year, except during fruit development, when reductions in the contents of N, P, K, Mg and Cu were observed.

The reed canary grass as a source of energy was tested in field experiments on small plots at three different sites in 1996-2003. The effects of soil and weather conditions, different times of harvest (July, November, March) and different doses of nitrogen fertilization (0, 30, 60 kg/ha) on yields of phytomass were investigated. The effects of the harvest time on the water content in harvested phytomass, loss of phytomass in different harvest period and the content of basic nutrients and heavy metals in plants were all specified. The influence of the year, site and N fertilization on yields of phytomass of the reed canary grass was highly significant. The reed canary grass responded positively to increasing doses of nitrogen by the increase of yields of phytomass. On the averages of years and sites, the N application dose of 30 kg/ha increased dry phytomass yields of the reed canary grass harvested in November by 14.6% (1.08 t/ha). The higher dosage of N 60 kg/ha increased yields of phytomass of the reed canary grass at all sites by 32.8% (2.08 t/ha) on average in contrast with variants without fertilization. By the dose of N 60 kg/ha, the dry above-ground phytomass harvested in autumn was 10.04 t/ha in Ruzyně, 8.27 t/ha in Lukavec and 6.94 t/hain Chomutov on average over the whole period. The later times of harvest resulted in a decrease of the average yield of phytomass (8.41 t/ha in July, 8.00 t/ha in November and 6.04 t/ha in March) and the average water content (64.3% - 45.2% - 21.5%); on the contrary, energy value of phytomass increased (16.93 GJ/t - 17.02 GJ/t - 17.19 GJ/t). The average content of ash in plants varied from 6.5% in Lukavec to 9.31% in Chomutov. The content of heavy metals in plants never exceeded the highest permissible values set in the Czech Republic for food and feed purposes.

The role of titanium (Ti) in plant metabolism is not so far fully clear. Many positive beneficial effects as well as a few adverse effects of Ti application are described in literature. The objective of our study was to investigate the effects of Ti foliar applications alone or in combination with Mg on the yield and accumulation of essential cations in consumable portions of frequently grown agricultural crops (potatoes, winter wheat and spring barley) grown under reduced and optimum nitrogen availability in field conditions. Nitrogen side dress fertilization significantly affected the investigated parameters, especially yield and N content. The effect of foliar Ti applications was substantially influenced by the nutrient N status of the individual plants. The plant response to Ti applications was almost negligible under N deficiency. At N treated plots the responses were much clearer but not many significant differences were found confirming high soil buffering capacity and many counteracting effects under field conditions.

The aim of this paper was a comparison of the content of nitrogen and basic mineral components (P, K, Ca and Mg) in pasture sward in dependence on the period of utilization. The studies were carried out in 1996–2004 in a pasture experiment on peat-muck soil. Changes of the content of nutrients in the pasture sward were introduced in the first and third regrowth in two periods of utilization (years 1998–1999 and 2003–2004). Mixtures with different varieties of Lolium perenne were involved in research (Polish – ‘Anna’, ‘Arka’, ‘Maja’, ‘Rela’, ‘Solen’ and SZD-291 strain as well as Dutch – ‘Baristra’, ‘Barezane’ and ‘Barlano’). To estimate the chemical composition of fodder a sward of control mixture was chosen (without Lolium perenne) and mixtures with selected varieties of this species (‘Anna’, Maja’, ‘Solen’, ‘Baristra’, ‘Barezane’ and ‘Barlano’). The research stated appreciable differentiation of the most of studied components in dependence on regrowth as well as period of utilization. The content of nutrients was higher in the sward of third regrowth (except phosphorus), as well in the first and the second periods of utilization. Pasture fodder was characterized by a much by higher content of nitrogen in the second period of utilization (years 2003–2004). There was also found a higher content of potassium and calcium. However, the content of magnesium and phosphorus was not clearly diverse in dependence on the period of utilization. The content of the studied components oscillated in the range of optimum or higher values (mainly nitrogen in the second period of utilization).

Copyright of Acta Scientiarum: Biological Sciences is the property of Universidade Estadual de Maringa 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.)

To study the effects of different storage methods and time on content of nutrients in biogas slurry of straw, two storage methods were carried out on biogas slurry between open storage and airtight storage conditions at normal atmospheric temperature. The contents of N, P, K, and organic matter in biogas slurry of straw were determined in different storage times. The results showed that; during the process of biogas slurry storage, little change occurred in the content of the organic matter while the total content of N. P. K significantly declined; up to 50 days, the total content of N. P. K reduced to nearly 80%-90%. Because the contents of N, P. K in biogas slurry reduced less in airtight storage conditions so that a better result was found on airtight storage methods than open storage methods in fertilizer field of biogas slurry of straw. [ABSTRACT FROM AUTHOR]