Current Issue : April - June Volume : 2011 Issue Number : 2 Articles : 7 Articles
The relationships between basic and applied agricultural R&D, developed and developing country R&D and between R&D, extension, technology and productivity growth are outlined. The declining growth rates of public R&D expenditures are related to output growth and crop yields, where growth rates have also fallen, especially in the developed countries. However, growth in output value per hectare has not declined in the developing countries and labour productivity growth has increased except in the EU. Total factor productivity has generally increased, however it is measured. The public sector share of R&D expenditures has fallen and there has been rapid concentration in the private sector, where six multinationals now dominate. These companies are accumulating intellectual property to an extent that the public and international institutions are disadvantaged. This represents a threat to the global commons in agricultural technology on which the green revolution has depended. Estimates of the increased R&D expenditures needed to feed 9 billion people by 2050 and how these should be targeted, especially by the Consultative Group on International Agricultural Research (CGIAR), show that the amounts are feasible and that targeting sub-Saharan Africa (SSA) and South Asia can best increase output growth and reduce poverty. Lack of income growth in SSA is seen as the most insoluble problem....
Harvesting is one of the most important operations in coffee production systems.\r\nThis operation has a high cost and impact on the final quality of the product. To reduce production costs, producers are looking for ways to mechanize this operation. Harvesting machines generally detach fruits from the coffee plant by vibration and/or impact. The objective of this work was to study the effect of the amplitude and frequency of vibration on the efficiency of coffee fruit harvesting. Vibration tests of coffee branches were performed in a laboratory using an electromagnetic shaker. The tests were performed using amplitudes in the range of 3.75 to 7.50 mm and frequencies from 13.33 to 26.67 Hz. Coffee branches from two different varieties were used for evaluation, Catua� Vermelho and Mundo Novo. It was verified that harvesting efficiency is directly related to the acceleration reached by the fruits during the harvesting process. The frequencies of 23.33 and 26.67 Hz and amplitudes of 6.25 and 7.50 mm resulted in the highest harvesting efficiency of ripe coffee cherries for both varieties. However, the harvesting efficiency for the Mundo Novo variety was higher than that of the Catua� Vermelho\r\nvariety at the studied frequency and amplitude ranges in this work....
Modern agriculture is heavily dependent on fossil resources. Both direct energy use for crop management and indirect energy use for fertilizers, pesticides and machinery production have contributed to the major increases in food production seen since the 1960s. However, the relationship between energy inputs and yields is not linear. Low-energy inputs can lead to lower yields and perversely to higher energy demands per tonne of harvested product. At the other extreme, increasing energy inputs can lead to ever-smaller yield gains. Although fossil fuels remain the dominant source of energy for agriculture, the mix of fuels used differs owing to the different fertilization and cultivation requirements of individual crops. Nitrogen fertilizer production uses large amounts of natural gas and some coal, and can account for more than 50 per cent of total energy use in commercial agriculture. Oil accounts for between 30 and 75 per cent of energy inputs of UK agriculture, depending on the cropping system. While agriculture remains dependent on fossil sources of energy, food prices will couple to fossil energy prices and food production will remain a significant contributor to anthropogenic greenhouse gas emissions. Technological developments, changes in crop management, and renewable energy will all play important roles in increasing the energy efficiency of agriculture and reducing its reliance of fossil resources....
Morphology and physiology of the plants can be affected by the production of Reactive Oxygen Species (ROS). Peroxidases Class III enzymes are scavenge ROS and protect from the stress, improve plant productivity. We studied the seasonal and ploidy level variations in peroxidase (POX) and catalase (CAT) activitiesin eight colhitetraploids and their putative diploids of mulberry in Summer, Rainey and Winter seasons. Enzymatic assay was done by using substrates Hydrogen peroxide (H2O2) and Guicolfor CAT and POX respectively. Activities of POX and CAT were high in summer season, and in diploids. Within the ploidy, genotypes showed varied activities of POX and CAT. This information helps in selection of stress resistant genotypes and improves the activities of triploidy breeding programme....
This contribution reviews the possibility of using the by-products from biodiesel production as substrates for anaerobic digestion and production of biogas. The process of biodiesel production is predominantly carried out by catalyzed transesterification. Besides desired methylesters, this reaction provides also few other products, including crude glycerol, oil-pressed cakes, and washing water. Crude glycerol or g-phase is heavier separate liquid phase, composed mainly by glycerol. A couple of studies have demonstrated the possibility of biogas production, using g-phase as a single substrate, and it has also shown a great potential as a cosubstrate by anaerobic treatment of different types of organic waste or energy crops. Oil cakes or oil meals are solid residues obtained after oil extraction from the seeds. Another possible by-product is the washing water from raw biodiesel purification, which is an oily and soapy liquid. All of these materials have been suggested as feasible substrates for anaerobic degradation, although some issues and inhibitory factors have to be considered....
Ground water resources for irrigated agriculture are becoming increasing limited in semiarid regions of the world. Subsurface drip irrigation (SDI) and a no-till conservation tillage system were evaluated over 3 years on cotton (Gossypium hirsutum, L.) production and fiber quality in north Texas. Subsurface drip irrigation significantly increased cotton yields over that from furrow irrigation in 2 of 3 yr. When averaged over 3 yr, the cover crop treatments on 1 and 2 m drip line spacing and a 100% ET replacement yielded numerically more than the companion treatments without a cover crop. Across years, the SDI treatments significantly increased loan values by an average of $0.045?kg-1 over furrow-irrigated cotton. Within SDI, deficit irrigation did not appear to affect cotton yield in proportion to the amount of restricted irrigation. In 2003, a 50% reduction in ET replacement under conventional tillage reduced yield only 22%, indicating that a 100% ET replacement may not be necessary to produce economically acceptable yields. Results from this study provide preliminary evidence that cover crops may actually prove beneficial under SDI systems and could play a role in developing best management practices that incorporate conservation tillage practices....
Plant kingdom exhibits wide range of diversity, mulberry is a such plant exhibits relatively different protein content between the genotypes. Proteins in the mulberry directly correlate with the silk protein in the silkworm Bombyx mori. There were eight colchitetraploids and their putative diploids selected, assayed leaf protein spectrophotometrically by using BSA as standard. All the genotypesd selected, exhibited variation in their whole protein content on their maturity, genotypes, ploidy level and in season. This ionformation peovide basic knowledge to select a genotypes for breeding, cytological studies and also pharmaceutical industries....
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