Reduced tillage in temperate organic farming: implications for crop management and forage production

To promote conservation tillage in organic farming systems, weed control and ley removal within arable-ley rotations need to be optimized. A long-term field trial was thus established in Frick, Switzerland in 2002 on a clayey soil and with a mean precipitation of 1000 mm/year. The tillage experiment distinguished between conventional tillage with mouldboard ploughing (CT, 15 cm depth) and reduced tillage (RT), including a chisel plough (15 cm) and a stubble cleaner (5 cm). Results of a 2-year grass-clover ley (2006/2007) and silage maize (2008) are presented. Due to dry conditions, mean grass-clover yields were 25% higher in RT than in CT, indicating better water retention of RT soils. Clover cover and mineral contents of the fodder mixture were also higher in RT. The ley was successfully removed in autumn 2007 in RT plots, and a winter pea catch crop was sown before maize. In CT, ploughing took place in spring 2008. Maize yields were 34% higher in RT than in CT, despite a two- to three-fold higher but still tolerable weed infestation. Maize in RT plots benefited from an additional 61.5 kg of easily decomposable organic N/ha incorporated into the soil via the pea mulch. Measurement of arbuscular mycorrhizal colonization of maize roots indicated a similar mechanical disturbance of the topsoil through the reduced ley removal system compared with ploughing. It is suggested that RT is applicable in organic farming, even in arable-ley rotations, but long-term effects need further assessment.     

Improving Potato Tuber Quality and Production by Targeted Calcium Nutrition: the Discovery of Tuber Roots Leading to a New Concept in Potato Nutrition

Calcium plays a major role in plant growth and development and in the maintenance and modulation of various cell functions, especially related to membrane structure and function and to cell wall structure. Calcium stabilizes cell membranes by bridging polar head groups of phospholipids at the membrane surface. Calcium is also an integral part of the cell wall where it provides stable intra-molecular linkages between pectin molecules, resulting in cell wall rigidity. A change in the cytosolic calcium concentration is also known to provide a cellular signal that regulates metabolism and mediates plant responses to stresses.     

Mechanical Evaluation of the Equine Laryngoplasty

Objectives: Mechanical evaluation of the equine laryngoplasty. Study Design: Experimental. Animal Population: Cadaveric cricoid (n=36) and arytenoid (46) cartilages. Methods: Arytenoid and cricoid cartilage specimens were embedded for testing. Suture material (2 Ethilon^®, 5 Ethibond^®, or 5 Fiberwire^®) was inserted simulating laryngoplasty procedures. Constructs were evaluated in single or cyclic loading. Single cycle tests recorded load at failure and stiffness. Cyclical tests recorded displacement after 10,000 cycles. ANOVA and t‐tests were used (significance P<.05). Results: The arytenoid Ethibond^® (241.10±47.67 N) constructs were stronger in single cycle than Ethilon^® (133.85±27.89 N) and Fiberwire^® (142.67±32.40 N). The cricoid Ethibond^® (220.39±49.11 N) constructs were stronger than Ethilon^® (171.93±21.19). The stiffness of Ethilon^® constructs was lower in both the arytenoid and cricoid compared with Ethibond^® and Fiberwire^®. The arytenoids failed at a lower load than the cricoids for Ethilon^® and Fiberwire^® but not Ethibond^® constructs. In cyclic testing complete failure of either cartilage did not occur. Arytenoid Ethibond^® constructs (0.43±0.21 mm) had less distraction than Ethilon^® (0.92±0.41 mm) and a trend for less compared with Fiberwire^® (0.83±0.43 mm; P=.0513). Cricoid Ethibond^® constructs (0.45±0.18 mm) had less distraction compared with Ethilon^® (1.04±0.30 mm) and Fiberwire^® (0.97±0.45 mm). Conclusions: Ethibond^® was superior to Ethilon^® and Fiberwire^® constructs in vitro. Clinical Relevance: Abduction loss after laryngoplasty is a common complication. The results of this study suggest that the use of Ethibond^® should minimize abduction loss after surgery relative to the other materials tested.     

‘Slippage’ in the Implementation of Forest Policy by Local Officials: A Case Study of a Protected Area Management in Lao PDR

A progressive part of protected area management program in Lao PDR is a land and forest allocation program which contains critical elements that delegate right of land and forest use to local people. This study analyzes the gap between the original intent of the program and its actual implementation by local officials in Phou Xang He protected area, and discusses policy issues that need to be addressed. It appears that several types of non-compliance with regulations by local people have occurred, with local officials tacitly ignoring infractions. By switching viewpoints, however, it appears that the local officials permit these infractions as a way of allowing local people to secure their livelihoods. As constraints on the realities of land and forest use vary widely in and around villages in different locales, there is a need for government to allow local officials flexibility in implementing policies.     

Continuity and discontinuity of the riparian vegetation along a fluvial corridor

The concept of continuity/discontinuity is applied to the riparian vegetation of the corridor of the River Adour (S.W. France), in order to precisely define longitudinal structure, and to test the degree of floristic continuity of the fluvial axis. The measure of floristic connectance along the river course is based on presence/absence data, and is applied to successive stretches of the river, at various resolution levels. This analysis shows that the River Adour corridor cannot be assumed to be floristically continuous. The observed discontinuities may correspond to two types of change in the riparian vegetation: zones of slow change (high level of floristic connectance) or zones of sharp change (low level of floristic connectance).     

Electron microscopic virus diagnosis in dogs, cats, calves, swine and foals in the year 1989

During 1989 fecal and gut samples of 598 dogs, 189 cats, 496 calves, 100 pigs and 66 foals with diarrhoea were investigated for virus by electron microscopy. In samples of dogs and cats Parvovirus was detected in 18.5% and 8.5% of the samples, respectively; Coronavirus was found in 14.9% and in 16.4% of the specimens. In samples of calves Coronavirus dominated with a detection rate of 37.5%, followed by Rotavirus with 10.7% and not clearly identifiable particles resembling Coronavirus (4.2%). In 7.1% of the specimens Rotavirus as well as Coronavirus was found. In 33% of specimens from piglets Coronavirus was detected. 10.6% of the faeces from foals contained Coronavirus-like particles. Between 1987 and 1989 the detection rate of Parvovirus in faeces from dogs and cats decreased from 24.2% to 18.6% and from 17.5% to 8.5%. Coronaviruses in calves, dogs and cats increased from 22.9% to 37.5%, from 5.6% to 14.9% and from 8.2% to 16.4% of the samples investigated.     

Effects of Amylopectin/Amylose Starch Ratio on Growth, Body Composition and Glycemic Response of Sunshine Bass Morone chrysops × M. saxatilis

Manipulation of the ratio of amylopectin (α‐[1,4] and α‐[1,6] linked glucose) to amylose (α‐[1,41 linked glucose) starches in the carbohydrate fraction of the diet has been used to improve carbohydrate and lipid metabolism in mammalian models. A 10‐wk feeding trial was conducted to determine the effect of dietary amylopectin/amylose ratio on growth and composition of growth of advanced sunshine bass (Morone chrysops × M. saxatilis) fingerlings (60 g, initial weight). Fish were fed cold‐pelleted, semipurified, isonitrogenous (35% crude protein), isocaloric (3.6 kcaVg protein), isolipidic (5%) diets containing 25% carbohydrate. The carbohydrate fraction of the diets was composed of either glucose, dextrin, 100% amylopectin/0% amylose, 70% amylopectin/30% amylose, or 30% amylopectin/70% amylose. Diets differing in ratios of amylopectin/amylose were achieved by adjusting the proportion of high‐amylopectin (100% amylopectin) to high‐amylose (70% amylose) corn starch. Diets were fed to fish in quadruplicate 76‐L tanks (seven fish/tank) connected to a brackish water (5‐7%v) recirculating culture system with biofiltration. Weight gain ranged from 195 to 236% of initial weight (60 g) and was significantly greater (P < 0.1) for fish fed diets containing 25% carbohydrate as dextrin or as 70% amylose and significantly lower in fish fed diets in which carbohydrate was composed of 30% amylose, 100% amylopectin, or glucose. Feed efficiency ranged from 0.52 to 0.61 and was higher in fish fed the diet containing the highest concentration of amylose and lower in fish fed the diet containing glucose. Hepatosomatic index was highest (2.71) in fish fed the diet containing glucose and lowest (1.401.45) in fish fed diets containing high‐amylose cornstarch. Intraperitoneal fat ratio was distinctly lower in fish fed diets containing some amylose as compared to those fed diets without amylose. Liver lipid was significantly lower (4.8%) in fish fed the diet containing glucose and almost twice as high (7.3‐8.9%) in fish fed the diets containing any starch. Glycogen content of the liver decreased from approximately 12% in fish fed the diet containing glucose to 5% in fish fed the diets containing amylose. Muscle proximate composition and ratio were unaffected by the dietary treatments. Fasting levels (15 h) of blood glucose in fish reared for 10 wk on the diet containing glucose were significantly elevated (5.5 mmol/L) when compared to fasting levels of those that had been reared on diets containing starch (3.4‐1.1 mmol/L). Fish fed the diet containing glucose exhibited maximum blood concentrations (14.6 mmoVL) 4 h postprandial then rapidly declined to nearly fasting levels within 8 h postprandial. In contrast, maximum plasma glucose concentrations in fish fed diets containing starch were roughly half (6.8‐8.1 mmol/L) those of fish fed the diet containing glucose. Blood glucose in fish fed diets containing dextrin or predominantly amylopectin starch remained elevated longer than that of fish fed diets containing glucose or predominantly amylose starch. Glycemic response appeared to decrease with increasing dietary amylose content. These data suggest that feeding diets in which a greater portion of the starch is amylose may be a useful strategy for improving carbohydrate use in sunshine bass.     

Evaluation of the Brucella abortus species-specific polymerase chain reaction assay, an improved version of the Brucella AMOS polymerase chain reaction assay for cattle.

In a blind test, 344 samples representing 80 bacterial isolates were analyzed by the Brucella abortus species-specific polymerase chain reaction (BaSS PCR) assay for the identification and discrimination of B. abortus field strains (wild-type biovars 1, 2, and 4) from 1) B. abortus vaccine strains, 2) other Brucella species, and 3) non-Brucella bacteria. Identical samples were tested in 2 laboratories. Half the samples were fully viable, and half were bacteria that had been killed by methanol fixation. The results in 1 laboratory correctly identified 100% of the samples, resulting in a predictive value of 100% for all categories and 100% sensitivity and specificity under the prescribed conditions. The second laboratory misidentified 31 samples, resulting in a range of 66.7-100% sensitivity, 93.2-99.7% specificity, and 77.3-98.2% predictive values depending on the category. There was no significant difference in viable versus fixed bacteria for either laboratory. Subsequent review of the protocol indicated that contamination was the likely cause of 26 of the 31 erroneous identifications. The results show that the BaSS PCR assay has the potential to be a very reliable screening tool for B. abortus identification. However, the data also provide a cautionary reminder of the importance of preventing contamination in diagnostic PCR.