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991.
Paige E Boyle Michael D Richardson Mary C Savin Douglas E Karcher Daniel A Potter 《Pest management science》2019,75(8):2071-2078
Earthworm activity is beneficial in most natural and agricultural systems, but excessive earthworm casting is a problem on sports fields worldwide. Expulsion of soil‐rich earthworm fecal matter, or casts, as mounds of soil on the turf canopy can muddy the surface, reduce photosynthesis, and lead to thinning, weed invasion and surface softening. Casts affect ball roll on sports fields, cause fouling of maintenance equipment, and dull mower blades. Build‐up of cast material on reel mower units can affect height and quality of cut. Casting activity is dependent on environmental conditions such as soil texture, temperature, moisture, pH, and organic matter. Response to environmental conditions varies by species. Management options are limited, because no pesticides are specifically labeled for earthworm control at this time, and cultural control methods such as soil modification, turfgrass clipping removal, and sand topdressing have limited and inconsistent efficacy. Products containing plant‐derived saponins and irritants show promise for earthworm management. Pest management practices to mitigate excessive earthworm casting will likely need to be species‐specific, but limited knowledge of earthworm identification by end‐users further inhibits the efficacy of control measures. © 2019 Society of Chemical Industry 相似文献
992.
Ahlem Zrig Jorge F. S. Ferreira Foued Hamouda Taieb Tounekti Samy Selim Soad Al Jaouni 《Arid Land Research and Management》2019,33(3):297-320
Salinity reduces plant biomass and may lead to death when severe. To cope with the negative effects of this stress, plant species present specific physiological or biochemical responses. In this work, we hypothesized that spraying salt-stressed thyme leaves with K+ and Ca2+ could mitigate the negative effects of salinity on plant growth and metabolism. To test this hypothesis, we grew thyme plants under salinity stress for two and four weeks before applying foliar sprays. Also, to test the effect of stress relief, treated plants were allowed two weeks of recovery after four weeks of salt stress. In general, after two and four weeks of salinity stress, the leaf fresh weight of thyme plants was reduced by 31 and 43%, respectively. Salinity also decreased the relative water content, water, and osmotic potentials and led to ion imbalances and nutrient deficiencies. Salinity altered concentration of some essential oils, but leaf antioxidant contents remained fairly stable, except for a significant increase for plants under NaCl?+?KCl two weeks after treatment. Our results indicated that stressed plants accumulated significantly more soluble sugars and amino acids in comparison with the control. Foliar sprays with KCl and CaCl2 reversed the negative effects of salinity on plant biomass and induced the accumulations of compatible solutes. Moreover, concentrations of some essential oils and gallic acid increased in sprayed plants, but these effects were dependent on the type and duration of the treatment. Overall, spraying leaves with K+ and Ca2+ was able to mitigate salinity stress in Thymus vulgaris even during the recovery period. 相似文献
993.
Sjolund M. Jennifer Arnsdorf Yvonne M. Carnegie Mairi Fornefeld Eva Will Torsten 《植物病害和植物保护杂志》2019,126(1):89-92
Journal of Plant Diseases and Protection - Psyllids are small, phloem-feeding insects. Several species are vectors of economically important pathogens, such as ‘Candidatus Liberibacter... 相似文献
994.
Journal of Plant Diseases and Protection - Dasineura oleae is a gall midge on leaves and branches of olive trees. Due to the scarcity of information regarding to the infestation and phenology of D.... 相似文献
995.
Journal of Plant Diseases and Protection - Cowpea mosaic virus is among the most economically important viruses infecting cowpea. Incidence of infection was assessed in two governorates in Egypt,... 相似文献
996.
Journal of Plant Diseases and Protection - Gmelina arborea (Gmelina) is a drought-tolerant tree species with rapid growth. It has excellent wood properties, and these have made this tree an... 相似文献
997.
Miguel A. Vela Humberto Villarreal Marcelo Araneda F. J. Espinosa‐Faller 《Journal of the World Aquaculture Society》2019,50(1):87-103
Preliminary technical baseline information for the inland culture of juvenile red drum, Sciaenops ocellatus, in a freshwater fish hatchery is presented. Three initial stocking densities (d1 = 83, d2 = 167, and d3 = 250 fish/m3) were tested in a semirecirculation system for 575 days using a commercially available feed (48.1% protein, 25% lipids, and 0.13% fiber). Initial and final mean fish weight were 7.11 ± 0.02 g and 287.6 ± 27 g. As carrying capacity appeared to have been reached, only data from Days 1–333 were analyzed. One‐way ANOVA analyses indicated that the survival rate of the smaller density (d1 =40 ± 3.7%) was significantly different from the other two densities (d3 = 21 ± 1.1% and d2 = 23 ± 1.0%), which did not differ between them. Absolute growth rate (0.87 ± 0.02 g/day) was not significantly different between densities (F = 0.23. p = .801). Neither was weight significantly different between treatments. There were significant differences in the feed conversion rate (FCR) between densities (F = 8.54; p = .02). FCR for d1 was significantly lower than for the two other densities, which did not differ from each other. A von Bertalanffy growth model was adjusted (R2 = 0.95), and weight–length relationship presented negative allometric values (b = 2.85, R2 = 0.98). 相似文献
998.
Romi Novriadi Elizabeth Spangler D. Allen Davis 《Journal of the World Aquaculture Society》2019,50(2):433-447
The present study was designed to investigate the effects of diets containing advanced soy products (enzyme‐treated soy and fermented soy) or corn protein concentrate (CPC) in combination with porcine meal (PM) to completely replace poultry byproduct meal (PBM) on growth performance, body composition, and distal intestine histology of Florida pompano, Trachinotus carolinus. Four experimental diets were formulated to be isonitrogenous and isolipidic, to contain 400 g/kg crude protein and 80 g/kg lipid. A reference diet (PBM diet [PBMD]) contained 150 g/kg PBM and 495 g/kg soybean meal (SBM), and three test diets were formulated replacing PBM with 15 g/kg of CPC (CPC diet [CPCD]) or replacing all SBM and PBM with 535 g/kg fermented soy (fermented soybean meal diet [FSBMD]) or 451.3 g/kg enzyme‐treated soy (enzyme‐treated soybean meal diet [ESBMD]). All three test diets were supplemented with 38 g/kg of PM. Diets were fed based on a percentage of bodyweight adjusted after sampling the fish every 2 weeks to triplicate groups of Florida pompano juveniles (mean weight 8.06 ± 0.22 g). After 8 weeks of feeding, fish fed CPCD and ESBMD performed equally well in terms of final body weight, thermal growth coefficient, and percentage weight gain in comparison to fish fed PBMD. In all cases, feeding FSBMD resulted in poor feed conversion and lower feed intake compared to other treatments. Protein retention efficiency, whole‐body proximate composition, phosphorus, sulfur, potassium, magnesium, calcium, sodium, and zinc contents were not significantly influenced by the dietary treatments. The results obtained in the present histological study showed no significant differences in the thickness of serous layer, muscular layer, and submucosal layer of the intestine among treatments. Fish fed CPCD showed a significant widening of the lamina propria with an increase of cellular infiltration and higher presence of goblet cells compared to other dietary treatment. Based on these results, 451 g/kg ESBM or combination of 150 g/kg of CPC and 495 g/kg SBM supplemented with 38 g/kg PM can be utilized to develop a practical diet for juvenile Florida pompano without impacting growth, nutritive parameters, and several distal intestine health parameters. 相似文献
999.
Fabio Soller Luke A. Roy D. Allen Davis 《Journal of the World Aquaculture Society》2019,50(1):186-203
Stearine fish oil (SFO) and palm oil (PO) have emerged as promising alternatives for the replacement of fish oil (FO) in aquafeeds. This study evaluated the replacement of FO with alternative oils in practical diets for Litopenaeus vannamei. In a clear brackish water study (14.1 g/L) utilizing shrimp (0.29 ± 0.02 g, initial weight), FO was replaced by SFO at inclusion ratios of 100:0, 75:25, 50:50, 25:75, and 0:100 (FO:SFO) and PO as 90% of FO. After 55 days, no significant differences (p < 0.05) in final weight, growth, or survival of shrimp were observed. A second trial (8 weeks) in low‐salinity water (2.1 g/L) with shrimp (0.92 ± 0.02 g, initial weight) evaluated diets with 100% FO, 100% SFO, 90% PO, 90% soybean oil (SO), or 90% flaxseed oil (FXO) as a replacement for FO and four commercially produced diets with 2% of FO, SO, PO, or FXO. One treatment received half rations of the commercial FO diet, and one treatment was based entirely on natural productivity. Results show that the fatty acid profiles of the tail muscle conformed to the lipids of the feed, and highly unsaturated fatty acids (HUFAs) were preserved. Following 8 weeks of culture, there were no significant differences in production performance. 相似文献
1000.
Karen E. Jensen J. Christopher Taylor Robert J. Barry Louis R. D'Abramo D. Allen Davis Stephen A. Watts 《Journal of the World Aquaculture Society》2019,50(3):614-621
Sea urchins produce high‐energy, membrane‐bound fecal pellets that contain residual nutrients and large quantities of microbiota. These egesta are readily consumed by the shrimp, Litopenaeus vannamei. Egesta of the sea urchin, Lytechinus variegatus, were evaluated as a feed supplement or total replacement for a commercial shrimp diet. Shrimp were stocked at 0.49 g ± 0.06 g initial body weight and housed individually in 2.8‐L tanks in a commercial recirculating zebrafish system. Shrimp were assigned to one of six diets: commercial shrimp feed, reference sea urchin feed, collected dried sea urchin egesta, collected wet sea urchin egesta, half ration of shrimp feed and half collected wet sea urchin egesta, and egesta naturally produced by two sea urchins in polyculture. Equivalent dry matter amounts of each diet were proffered to shrimp in each treatment twice daily, except for those that had complete access to natural egesta excreted by sea urchins in polyculture. Sea urchins were proffered a reference sea urchin feed at 2% body weight daily. After 27 days, shrimp proffered collected dried or wet egesta did not differ significantly in percent weight gain and showed the lowest weight gain. The percent weight gain of shrimp fed the commercial shrimp diet did not differ significantly from that of the shrimp fed half commercial shrimp diet and half egesta. The highest weight gain was recorded for those shrimp that consumed the untouched egesta produced by sea urchins in polyculture. These data suggest that consumed egesta have noteworthy nutritional value and therefore would be beneficial to the culture of extractive species in an integrated multitrophic aquaculture system. 相似文献