Suchergebnisse

Lettuce (Lactuca sativa L.) is a vegetable of global consumption and his production has been increasing. The nitrate content in leaves is an important aspect of his quality, closely related to consumer health. In order to assess the quality of lettuce produced under cover, in terms of dry matter and nitrate contents in order to establish whether there were differences between times and dates harvest. To compare them, if they were within the limits established by the legislation of the European Commission. The work was conducted between December 2005 and December 2006, in an establishment located in Toay, Province of La Pampa. The results were analyzed using ANOVA by arrangement factorial of the information. For comparison of treatment means Tukey test (p ≤ 0.05) was used. The experimental unit was 400 m2, which extracted 8 lettuce plants representative of the crop, at 9 and 17 h, in a bimonthly. Fresh weight, dry weight and nitrate content of each plant were determined. The results of the analysis of dry matter showed highly significant differences between times and dates, while for nitrate only significant differences between dates. All samples are below the limits established by the legislation of the European Commission. ; La lechuga (Lactuca sativa L.), es una hortaliza de consumo mundial y su producción ha ido en aumento. El contenido de nitratos en hojas es un aspecto importante de su calidad, íntimamente relacionada con la salud del consumidor. Con el objetivo de evaluar la calidad de lechuga, producida bajo cubierta, en cuanto a su contenido de materia seca y nitratos de manera de establecer si existían diferencias entre horarios y fechas de cosecha. Para con posterioridad compararlos si se encontraban dentro de los límites establecidos por la Legislación de la Comisión Europea. El trabajo se realizó entre Diciembre de 2005 y Diciembre de 2006, en un establecimiento ubicado en Toay, Provincia de La Pampa. Los resultados se analizaron mediante ANOVA con arreglo factorial de los datos. Para la comparación de las medias de los tratamientos se utilizó el test de Tukey (p≤ 0,05). La unidad experimental fue de 400 m2, donde se extrajeron 8 plantas de lechuga representativas del cultivo, a las 9 y 17 h, en forma bimensual. A cada planta se le determinó peso fresco, peso seco y contenido de nitratos. Los resultados obtenidos del análisis de materia seca muestran diferencias altamente significativas entre horas y fechas, mientras que para el contenido de nitratos se encontraron diferencias significativas solo entre fechas. Todas las muestras analizadas se encuentran por debajo de los límites establecidos por la Legislación de la Comisión Europea.

This photo essay by Matt Black depicts the often devastating impact of drought on the landscapes and communities of California's Central Valley.

Sugar beet is considered as biogas substrate because of its high yield. However, varieties differ in quality, in particular sugar content, which might affect biogas formation. The study aimed at analysing the impact of different beet qualities on biogas formation. Furthermore, parameters describing beet quality for anaerobic digestion should be found.

From 2009 to 2011 field trials with several sugar beet varieties and a fodder beet variety were conducted with different N application rates at sites near Göttingen and Regensburg to get a broad range of beet qualities. The dry matter composition of beets, leaves, winter beet, bolters and maize was analysed. Discontinuous batch trials with fresh beet material were conducted to determine biogas formation.

Sugar beet varieties did not differ in their dry matter composition and thus in biogas formation, whereas differences occurred between sugar beet and other substrates. Sugar beet was characterised by a high content of organic dry matter (98% oDM). The degradation time was mainly affected by the crude fibre content of the material. Therefore 90% of the biogas from sugar beet was formed within 3.5 days, whereas from winter beet, bolters and maize it took more than 10 days. The calculation of the specific biogas yield of different sugar beet qualities with two formulae resulted in lower values than determined in batch trials. A formula was derived to assess sugar beet quality for anaerobic digestion based on the sugar content, as increasing sugar contents lead to increasing specific biogas yields per kilogramme fresh matter.

The role of cassava in Indonesia is becoming more important, whether it is used for food, for industrial processing or for export. The government of Indonesia has established two policies in the agricultural sector, namely: food diversification and increased productivity in the uplands. Food diversification is needed to reduce dependency on rice as the principal food by way of utilizing various other carbohydrate sources, especially cassava. The policy to increase productivity in the uplands, on the other hand, is launched because the acreage of lowland rice fields has been declining over the years with the conversion of some of this land to non-agricultural use, especially on Java. One way of increasing productivity in the up lands is through crop diversification. However, this diversification program should not affect the current productivity of cassava, since cassava has always functioned as a dominant commodity produced in the uplands. For this reason, the intensification of cassava becomes necessary, through, for example, application of intercropping systems that use suitable plant types, varieties as well as appropriate cultural technologies. Efforts to improve cassava cultivars should be made and the methods to introduce them to the farmers should be improved. When cassava is meant to substitute for rice as a source of carbohydrate, a high-quality cultivar, characterized by low HCN in the roots, needs to be developed. On the other hand, when it is meant for industrial use, a high-yielding cultivar with high starch content, needs to be developed. Special cultivars may also need to be developed when cassava is to be grown under intercropping systems. Cassava breeding in Indonesia is presently done jointly by MARIF, CIAT and Brawijaya University in Malang. MARIF has recently released two new high-quality cultivars, named Malang 1 (parents: CM1015-19 x CM849-1) and Malang 2 (parents: CM922-2 x CM507-37). The selection program carried out by Brawijaya University has produced a number of promising cassava clones, labelled UB 1-2 (parents: MCol 22 x CM849-1), UB 15-10 (parents: CM586-1 x CM523-7), UB 477-2 (parents: CM1002-4), UB 881-5 (parents: CM849-1) and UB566-8 (parents: MBra 35). These clones show their greatest potential in the uplands of subhumid regions like East Java. UB 477-2 is a sweet clone, while clones UB 15-10 and UB 566-8 are suitable for growing under intercropping systems. These promising clones will not be released as high-quality cultivars before they undergo multi-location trials in at least 5 provinces, as stipulated by the Minister of Agriculture of the Republic of Indonesia.

There are many solutions to save energy during crystallization but they often imply huge investments. Hence, they are mainly applied during a complete retrofit. At the end of the 1990s, Tereos, France developed a new crystallization scheme based on the IRIS' "Programme Qualité", a 1st strike crystallization program, and syrup concentration requiring minimum investment. It has been tested in two factories that are now closed. As part of the recent investment program for energy, the group has successfully started two new crystallization projects, adding improvements thanks to its experience. Basics and advantages of this scheme are presented as well as the recent optimizations. Disadvantages and further modifications will be discussed.

Among the many neglected underutilized species, tuberous Andean root crops such as the ahipas (Pachyrhizus ahipa) constitute a promising alternative for increasing diversity in nutrient sources and food security at a regional level. ahipa × P. tuberosus). A significant objective was to determine protein and free amino acids in the roots to evaluate their food quality as protein supply. The interspecific hybrids have been found to possess the root quality to provide the crop with a higher dry matter content. The high dry matter content of the P. tuberosus Chuin materials is retained in the root quality of the hybrids. Food functional components such as carbohydrates, organic acids, and proteins were determined in several ahipa accessions and a stable (non-segregating) progeny of the interspecific hybrid, X207. The X207 roots showed a significantly higher dry matter content and a lower content in soluble sugars, but no significant differences were found in starch content or organic acids compared to the ahipa accessions. Regarding the root mineral contents, Fe and Mn concentrations in X207 were significantly raised compared to the average of ahipa accessions. Among the ahipa and the hybrid, no prominent differences in protein content or protein amino acids were found, being both partially defective in providing sufficient daily intake of some essential amino acids. Root weight, a central component of root yield, was significantly higher in X207, but thorough field studies are required to substantiate the hybrid's superior yield performance. ; European Union 613692