- Authors:
- Incrocci, L.
- Massa, D.
- Carmassi, G.
- Pulizzi, R.
- Maggini, R.
- Pardossi, A.
- Bibbiani, C.
- Source: Acta Hort 801, International Symposium on High Technology for Greenhouse System Management: Greensys2007
- Volume: 2
- Year: 2008
- Summary: A simple spreadsheet ( SIMULHYDRO) was designed to predict the consumption of both water and fertilizers, and the environmental impact associated to nutrient leaching, in greenhouse soilless cultures on the basis of a limited number of variables (such as global radiation, air temperature, and the ion composition of irrigation water) and parameters, the most important of which is the ion uptake concentration (i.e. the expected ratio between ion and water uptake by the crop). SIMULHYDRO aggregates three major models that run on a daily basis to estimated: (i) crop water uptake ( VU ); (ii) the ion composition and the electrical conductivity of recycling nutrient solution ( ECNS ); (iii) the ion composition of drainage water in open (free-drain) and semi-closed (with periodical discharge of the recirculating water) growing systems. SIMULHYDRO was used to simulate the water and mineral relations of greenhouse tomato plants grown in semi-closed substrate (rockwool) culture using saline water (approx. 9.5 mmol L -1 NaCl) and three different fertigation strategies: (A) VU was systematically compensated with nutrient solution at full strength ( ECNS =2.5 dS m -1) in order to maintain a (relatively) constant nutrient content; mostly due to the accumulation of ballast ions ( Na+ and Cl-), this strategy resulted in a progressive increase of ECNS till it reached a ceiling value ( ECNSMAX =4.5 dS m -1) tolerated by the crop, afterwards the recirculating water was flushed out; (B) an EC set-point of approx. 3.0 dS m -1 was maintained and the nutrient solution was flushed out whenever the N-NO 3- concentration decreased below 1.0 mmol L -1; (C) VU was initially compensated with nutrient solution at full strength, as in Strategy A; when ECNS reached 4.5 dS m -1, the mixing tank was refilled with fresh water only, in order to withdraw N from the nutrient solution before discharge. The experiment included also an open system to verify the possible influence of salinity build-up and/or nutrient depletion on crop yield. A good agreement was found between simulated and measured data. No important effects of the adopted strategies were observed on VU and fruit yield, although the former was significantly higher in open system than in the Strategies A and B. Strategies A and C reduced total water use compared to the others. The results confirmed that a semi-closed system conducted following the strategy of full nutrient solution replenishment (Strategy A) may produce a massive environmental pollution due to nutrient (nitrogen) leaching, although to a much lesser extent than open growing system.
- Authors:
- Source: Poljoprivreda / Agricultur
- Volume: 14
- Issue: 1(Supplement)
- Year: 2008
- Summary: This publication contain 26 abstracts of papers that cover topics on: food vs. fuel (a turning point for bioethanol); Dow Agrosciences today and new revolutionary solutions; using maize as a sugar crop; remarks to the current discussion on bioenergy (for the public and/or for the agricultural or rural areas only); the production of biofuels and its impact on agriculture in Croatia; fuels in tobacco production; the role of MATH/BTB proteins in egg cell and at the onset of wheat embryogenesis; transgenic plants resistant to insects; microsatellite diversity of M3sS maize population under recurrent selection; long-term selection experiments or transgenics for composition traits of maize grain; genetic diversity of wheat cultivars estimated by SSR markers; genomic approaches for improvement of drought adaptation in wheat; application of molecular methods in soyabean breeding programme at the Agricultural Institute Osijek (Croatia); implementation of DNA markers to improve breeding of forage legumes; biotechnology in fruit growing; changes in levels of activity of serine proteinase accompany the exposure of common bean to water deficit; tilling in the service of plant improvement; marker assisted selection for development of barley and wheat lines with requested traits; oat seed as a multifunctional subject for biotechnology; mechanism and regulation of nonsense-mediated mRNA decay as an essential quality control system of plants; biotechnology as a useful tool for nutritional improvement of cereal-based materials enriched with polyunsaturated fatty acids and pigments; grapevine habituation (understanding of factors that contribute to somaclonal variation and neoplastic transformation); Agrobacterium-mediated transformation of wheat; nutritional enhancement of lucerne through genetic engineering; genes behind smoke action; cycloxydim-tolerant maize from a breeder's standpoint.
- Authors:
- Belina, K. M.
- Steenwerth, K.
- Source: Applied Soil Ecology
- Volume: 40
- Issue: 2
- Year: 2008
- Summary: Impacts of soil tillage and cover crops on soil carbon (C) dynamics and microbiological function were investigated in a vineyard grown in California's mediterranean climate. We (1) compared soil organic matter (SOM), C dynamics and microbiological activity of two cover crops [Trios 102 (Triticale x Triosecale) ('Trios'), Merced Rye (Secale cereale) ('Rye')] with cultivation ('Cultivation') and (2) evaluated seasonal effects of soil temperature, water content, and precipitation on soil C dynamics (0-15 cm depth). From treatments established in November 2001, soils were sampled every 2-3 weeks from November 2005 to November 2006. Gravimetric water content (GWC) reflected winter and spring rainfall. Soil temperature did not differ among treatments, reflecting typical seasonal patterns. Few differences in C dynamics between cover crops existed, but microbial biomass C (MBC), dissolved organic C (DOC), and carbon dioxide (CO2) efflux in 'Trios' and 'Rye' were consistently 1.5-4-fold greater than 'Cultivation'. Cover crops were more effective at adding soil C than 'Cultivation'. Seasonal patterns in DOC, and CO2 efflux reflected changes in soil water content, but MBC displayed no temporal response. Decreases in DOC and potential microbial respiration (RESPmic) (i.e., microbially available C) also corresponded to or were preceded by increases in CO2 efflux, suggesting that DOC provided C for microbial respiration. Despite similar MBC, DOC, RESPmic, annual CO2 efflux and aboveground C content between the two cover crops, greater aboveground net primary productivity and SOM in 'Trios' indicated that 'Trios' provided more soil C than 'Rye'.
- Authors:
- Christopher, A.
- Thomas, B.
- Albaho, M.
- Source: International Journal of Vegetable Science
- Volume: 14
- Issue: 1
- Year: 2008
- Summary: Two hydroponic techniques, i.e. nutrient film technique and A-shaped aeroponics, and a closed insulated pallet system based on continuous subirrigation system with fertilizers in reservoirs to ensure a reserve within the root zone (CIPS) were evaluated and compared to the conventional soil-based cultivation method (control) in Kuwait. The experiment was conducted in an acrylic covered greenhouse having an evaporative cooling system with ambient temperatures ranging from 15 to 20degreesC at night and 24 to 35degreesC during the day from October 2005 to May 2006. The vegetative growth, flowering, and fruiting of bell pepper ( Capsicum annuum cv. Yara) and strawberry ( Fragaria vesca cv. Americana Porter) were evaluated. Yields were lower in the closed systems than in the control. Significant differences were observed between the amounts of water consumed in the soilless techniques, with consumption ranging from 42.9 to 62.9% of the control for pepper and 54.3 to 79.1% of the control for strawberry. CIPS was the most promising system for protected agriculture because of its simplicity, recyclability of most of its components, and water conservation efficiency.
- Authors:
- Agenbag, G. A.
- Louw, P. J. E.
- Fourie, J. C.
- Source: South African Journal of Enology and Viticulture
- Volume: 28
- Issue: 2
- Year: 2007
- Summary: The trial was conducted over a period of ten years (1993/94 to 2002/03) on a sandy soil in a Sauvignon blanc/Ramsey vineyard near Lutzville (31degrees35′S, 18degrees52′E), situated in the semi-arid Olifants River Valley of the Western Cape. Fourteen treatments, consisting of three grain species and four legumes, managed according to two cover crop management practices, were included. One management practice consisted of cover crops which were sown annually and full surface, post-emergence chemical control which was applied before bud break and when the berries reached pea size (BB). The second management practice consisted of cover crops which were sown biennially. Post-emergence chemical control was applied to the vine row before bud break and full surface when the berries reached pea size (AB). From 1999/2000 to 2002/03 the cover crops were sown annually, while the full surface post-emergence control applied at the end of November was advanced to mid-October. Two treatments in which Avena sativa L. v. Saia ('Saia' oats) and Vicia dasycarpa Ten. (grazing vetch) were sown annually, controlled mechanically in the work row and chemically in the vine row from bud break to harvest (MC), were also applied. These treatments were compared to a control, in which no cover crop was sown and MC was applied. A treatment in which no cover crop was sown and BB was applied (weedchem), was also included. During the third growing season of the vines (1994/95), the grapevine shoot mass of the BB treatments of grazing vetch and Medicago truncatula Gaertn. v. Paraggio ('Paraggio' medic) was significantly more than that of the AB and MC treatments, with the exception of Secale cereale L. v. Henog (AB) and grazing vetch (MC). The first harvest (1994/95) from the grapevines in the BB treatments was significantly higher than that of weedchem and the MC treatments. The grape yield of the BB treatments, grazing vetch (AB) and Ornithopus sativus L. v. Emena (pink Seradella) (AB) was significantly more than that of weedchem and the control during the 1997/98 season. The NO 3-N concentration in the leaf petioles in all the cover crop treatments was, with the exception of the AB treatments of rye, M. truncatula Gaertn. v. Parabinga ('Parabinga' medic) and grazing vetch, significantly higher than that in weedchem and the control, as measured during the 1994/95 season. The NO 3-N concentration in the leaf petioles of the BB and AB treatment of a species differed significantly. The N concentration in the juice of the cover crop treatments during the 1995/96 season was, with the exception of 'Saia' oats (MC) and 'Parabinga' medic (AB), significantly higher than that of weedchem and the control. During the 1998/99 season, the N concentration of the juice in the BB and AB treatments of grazing vetch and pink Seradella was significantly higher than that of the MC treatments, two rye treatments, weedchem and the AB treatments of the other cover crops. The concentration of Ca in the juice of the cover crop treatments was, with the exception of the pink Seradella treatments, significantly higher than that of weedchem and the control. Wine quality did not differ between treatments.
- Authors:
- Source: Oversigt over Landsfors<o>gene 2007. Fors<o>g og unders<o>gelser i de land<o>konomiske foreninger
- Year: 2007
- Summary: Work conducted by Landsforsgene, a collaborative body that undertakes field trials and experiments on crop plants in Denmark, is reported. A general introduction gives details of conditions in the 2007 growing season (warmer in spring and wetter than usual in summer), and their effects on factors such as the efficacy of fertilizer application and the harvest. The aim is to give growers a basis for future planning, taking account of environmental conditions and profitable plant production. Most of the report is devoted to separate sections covering individual crops: winter barley, winter rye, triticale, winter wheat, spring barley, oats, spring wheat, field peas, grass seeds, rape, hemp, spinach, strawberries, potatoes, sugar beet, pasture plants (grasses and clovers), and maize. Within these sections details of varieties, fertilizers, weeds, and diseases are provided in the text and in numerous tables and photographs. Other small sections deal with topics including organic production, fertilizers, plant breeding, statistical methods, policies, and names and addresses of suppliers. The report concludes with a list of the 23 authors of sections, and a comprehensive index.
- Authors:
- Barlow, E. W. R.
- Whetton, P. H.
- Webb, L. B.
- Source: Australian Journal of Grape and Wine Research
- Volume: 13
- Issue: 3
- Year: 2007
- Authors:
- de Moura, R. L.
- Klonsky, K. M.
- Peacock, W. L.
- Hashim-Buckey, J. M.
- Vasquez, S. J.
- Source: University of California Cooperative Extension Publication
- Year: 2007
- Authors:
- Year: 2007
- Summary: Chicago Climate Exchange (CCX) is the world's first and North America's only active voluntary, legally binding integrated trading system to reduce emissions of all six greenhouse gases (GHGs), with Offset Projects worldwide. CCX employs independent verification and has been trading GHG emission reductions since 2003. CCX Members that cannot reduce their own emissions can purchase credits from those who make extra emission cuts or from verified Offset Projects. CCX issues tradable Carbon Financial Instrument (CFI) contracts to owners or aggregators of eligible projects on the basis of sequestration, destruction or displacement of GHG emissions. Eligible projects include: agricultural methane, landfill methane, coal mine methane, agricultural and rangeland soil carbon, forestry and renewable energy.