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801.
The aim of the experiments was to evaluate a selection of faba bean (Vicia faba L.) var. minor varieties for further production improvement on the basis of their productivity and phenotype characteristics under the short season of the Northern European environmental conditions. The varieties evaluated were: Bauska, Favel, Fuego, Gloria, Jõgeva, Lielplatones, Priekulu and Priekulu viettejas. The highest and most stable average yield for 2015–2016 years was recorded in Bauska and Priekulu, with 3.77 and 3.64?t/ha, respectively. The incidence of chocolate spot and rust was in low to middling. Plant average height for 2015–2016 years was greatest in Bauska, Lielplatones and Priekulu vietejas, with 107.4, 110.7 and 110.0?cm, respectively. Resistance to lodging was best in Bauska and Fuego. From these yield and phenotype characteristics results we conclude that Lielplatones is the most suitable faba bean var. minor varieties for breeding in Northern European conditions, because of the following characteristics: middle yielding, quite high content of protein, very small seeds, low susceptibility to chocolate spot, good resistance to lodging. Thus almost every tested variety had some very good characteristics, which may also be valuable for the breeding of new varieties.  相似文献   
802.
Plant Foods for Human Nutrition - Thirteen fruits, eight legumes and three tubers consumed in the Andean regions of Ecuador were studied to determine their bioactive compounds, organic acids,...  相似文献   
803.
BACKGROUND: The efficacy of systemic applications of imidacloprid for the management of avocado thrips and avocado lace bug was determined in field trials. Following insecticide treatment by chemigation, leaves of appropriate age for each insect were sampled over a 6 month period and used for bioassays. Imidacloprid residues were measured by ELISA in leaves used for bioassays to determine concentrations of insecticide that were toxic to both pests. RESULTS: The uptake of imidacloprid into treated trees was extremely slow, peaking in the current year's leaf flush at only 8 ng cm?2 leaf tissue after 15 weeks. Avocado thrips mortality in bioassays with young flush leaves, the preferred feeding substrate for this insect, was minimal, indicating that imidacloprid concentrations were below threshold levels needed for effective control. Residues present in older leaves, which are preferred by the avocado lace bug, were higher than in young flush leaves, and provided good control of this pest. Probit analysis of bioassay data showed that the avocado lace bug (LC50 = 6.1 ng imidacloprid cm?2 leaf tissue) was more susceptible to imidacloprid than the avocado thrips (LC50 = 73 ng imidacloprid cm?2 leaf tissue). CONCLUSIONS: In spite of the slow uptake of imidacloprid into avocado trees, the levels of imidacloprid would be sufficient to control avocado lace bug infestations. In contrast, the slow uptake would be problematic for avocado thrips control because inadequate levels of insecticide accumulate in new flush foliage and would allow avocado thrips populations to build to levels that would subsequently damage developing avocado fruit. Copyright © 2010 Society of Chemical Industry  相似文献   
804.
The natural regeneration of non-serotinous Spanish black pine (Pinus nigra Arn. ssp. salzmannii) is known to be null or limited after severe wildfires. However, it remains challenging to define efficient management strategies within the burnt area, which can help to increase the post-fire resilience of this species. We conducted a direct seeding experiment during 2011–2015 to assess the effect of different post-fire management treatments (control, soil ripping, woodchips, and soil ripping?+?woodchips) performed in opposite slope-aspects (north- and south-facing) on pine emergence, seed predation, survival, growth, and biomass allocation during the early stages of seedling development (1–5 years) after a severe wildfire. Our results showed that the slope-aspect did not have an important effect in both the seedling emergence and seed predation rates. In contrast, the influence of slope-aspect was significant as both survival and growth of pine seedlings were reduced at the south-facing slope-aspect compared to the north-facing slope-aspect due to harsher environmental conditions. A variable and reduced impact on seedling emergence and seed predation rates was induced by both soil ripping and woodchips treatments. Overall, post-fire management treatments helped to enhance survival rates during early growth stages, although this effect was short-lasting. This knowledge can be used to define post-fire seeding management strategies oriented to enhance the resilience of severely burnt pine forest stands; therefore, while both the soil ripping and woodchips treatments might not be practices leading to increase their post-fire regeneration, direct seeding at north-facing slope-aspects could be a more appropriate management strategy.  相似文献   
805.
Based on macroecological data, we test the hypothesis whether European tree species of temperate and boreal distribution maintain their water and nutrient supply in the more arid southern margin of their distribution range by shifting to more fertile soils with higher water storage than in their humid core distribution range (cf. soil compensatory effects). To answer this question, we gathered a large dataset with more than 200,000 plots that we related to summer aridity (SA), derived from WorldClim data, as well as soil available water capacity (AWC) and soil nutrient status, derived from the European soil database. The soil compensatory effects on tree species distribution were tested through generalized additive models. The hypothesis of soil compensatory effects on tree species distribution under limiting aridity was supported in terms of statistical significance and plausibility. Compared to a bioclimatic baseline model, inclusion of soil variables systematically improved the models’ goodness of fit. However, the relevance measured as the gain in predictive performance was small, with largest improvements for P. sylvestris, Q. petraea and A. alba. All studied species, except P. sylvestris, preferred high AWC under high SA. For F. sylvatica, P. abies and Q. petraea, the compensatory effect of soil AWC under high SA was even more pronounced on acidic soils. Soil compensatory effects might have decisive implications for tree species redistribution and forest management strategies under anthropogenic climate change. Therefore, soil compensatory effects deserve more intensive investigation, ideally, in studies combining different spatial scales to reduce the uncertainty associated with the precision of soil information.  相似文献   
806.
In recent years, there has been an increasing interest in finding sustainable strategies for the efficient removal of contaminants from soils. The objective of this review is to examine the biochemical principles of specific genetic modifications in plants, their applications in the field for specific contaminants as phytotechnologies, and their international regulation. In addition, the review presents some biological aspects of rhizosphere-related phenomena, the interactions of organic and inorganic pollutants with plants, and the performance of the phytotechnologies across the continents. During the last few decades, at least eight genera of genetically modified plants (GMPs) have been tested and used for soil remediation with outstanding results. Arabidopsis, Nicotiana, and Oryza are the plant genera most widely studied. Specific plant genes such as metal transporters, chelators, metallothioneins, phytochelatins, and oxygenases have been transferred to plants to improve the elimination of contaminants in soil. We discuss some important aspects of gene manipulation and its application for removal of diverse contaminants. A key challenge faced by phytotechnologies is the final disposal of the generated biomass, from a safety aspect. We argue that the commercial success of phytotechnologies depends on the generation of valuable biomass on contaminated land and its use for bioenergy generation. The use of such technologies would promote a broader understanding of the importance of plants, especially GMPs, in the environment and their contribution to environmental sustainability.  相似文献   
807.
Cover crop (CC) residues protect the soil from erosion and their permanence on the surface is largely influenced by their biochemical constituents. In this study, the dynamics of CC residue decomposition by applying mathematical models was described. The kinetics of decomposition of residues was obtained from a laboratory incubation experiment. Three CC shoot residues were applied on the soil surface and incubated for 362 days (with eight sampling times). Oats and vetch residues decomposed the most than clover, where k values were 3.6 × 10?3, 3.7 × 10?3 and 5.3 × 10?3 day?1, respectively. The three-compartment model (nonstructural carbohydrates, cellulose–hemicellulose and lignin) to simulate residue decomposition presented a close fit between simulated and measured data. The decomposition rate constant (k) of CC can be used to estimate how long residues will remain in the field and how they could affect soil organic carbon.  相似文献   
808.

Objective

This study evaluated the effects in vitro and in vivo of Agaricus blazei against Haemonchus contortus in sheep.

Methods

The in vitro efficacy of aqueous extract on egg hatching inhibition (EHI) was investigated and after 72 h incubation with varying concentrations the effects on, blastomeres, embryonated eggs, and first stage larvae (L1) were evaluated. Larval development inhibition (LDI) for dry powder and the aqueous extract were evaluated in fecal cultures of sheep infected with H. contortus. In vivo efficacy was determined by reduction in fecal egg count (FEC). Lambs were treated with powder A. blazei (11.4 g/kg pc) or trichlorfon, or were untreated and the possible toxicity of this fungus was monitored by plasmatic enzyme analysis.

Results

Concentrations equal to and higher than 3.62 mg/mL and of aqueous extract were 100% effective in the EHI test. In the LDI test, LC90 was estimated for 5.66 and 106.0 mg/g fecal culture for aqueous extract and powder, respectively. The mean FEC in lambs 14 days post-treatment with A. blazei powder was significantly lower than observed for the negative control, and the serum levels of aspartate transaminase and alanine transaminase were normal.

Conclusion

The fungi supplementation promotes, respectively, high and moderate anthelmintic efficacy with in vitro and in vivo tests, respectively, suggesting it as an alternative or complementary treatment for haemonchosis in sheep.
  相似文献   
809.
Soybeans are of great importance in the world agricultural landscape, and their productive potential is significantly reduced by attacks from insect pests. Factors such as the expansion of national agricultural regions, together with no-tillage management and “off-season” maize cultivation, have favored the increase of secondary species such as Dichelops melacanthus (Dallas) (Hemiptera: Pentatomidae), intensifying the damage caused by the soybean stink bug complex. The use of resistant genotypes may be a valuable strategy as an alternative to the excessive use of chemical control in crops. This study evaluated the attractiveness and feeding preferences of the green-belly stink bug in 17 soybean genotypes in different maturity groups (early, semiearly, and late) to characterize the expression of antixenosis resistance. To this end, free-choice tests of attractiveness and food preference were performed under laboratory conditions. The early genotypes PI 171451 and D 75-10169, the semiearly genotypes IAC 78-2318, “IAC 100”, IAC 74-2832, PI 227687, and “IAC 24” and the late genotypes PI 274454, PI 274453, and L 1-1-01 expressed significant levels of antixenosis against adult D. melacanthus. These results will be useful for soybean breeding programs focusing on the stink bug resistance complex.  相似文献   
810.
Water, Air, & Soil Pollution - Biochar presents great promise as a technology that makes a substantial contribution in various fields of environmental research. However, existing knowledge is...  相似文献   
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