Dioclea grandiflora andDioclea sclerocarpa seeds. A nutritional study

A nutritional study ofDioclea grandiflora (Mucuna) andDioclea sclerocarpa, two legume seeds related toCanavalia which grow extensively in South America and are used as a human food source, has been carried out. Whilst both seeds, when fed to rats at a level equivalent to 100g seed protein kg^–1 diet gave poor nutritional performance, the anti-nutritional factors involved were apparently different. WithDioclea grandiflora, the presence in the seed of a soluble small molecular weight component, which caused food intake to be reduced to levels well below that required to meet minimum protein, energy, vitamin and mineral requirements, led to poor growth. This factor could be reduced substantially by exhaustive dialysis or by aqueous ethanol extraction of the meal. These procedures may have potential practical applications. In addition, the constitutent lectin, which was partially resistant in vitro and in vivo to degradation by gastrointestinal enzymes, also contributed to growth depression. WithDioclea sclerocarpa, a non-haemagglutinating pH 7 soluble factor was primarily responsible for the poor performance of rats. This factor could not be removed by exhaustive dialysis. The apparently poor protein digestibility observed may be due to increased secretion of endogenous nitrogen.     

Aqueous and methanolic extracts of Caulerpa mexicana suppress cell migration and ear edema induced by inflammatory agents

The regulation of the inflammatory response is essential to maintaining homeostasis. Several studies have investigated new drugs that may contribute to avoiding or minimizing excessive inflammatory process. The aim of this study was to evaluate the effect of extracts of green algae Caulerpa mexicana on models inflammation. In mice, the inflammatory peritonitis model is induced by zymosan. Previous treatment of mice with aqueous and methanolic extracts of C. mexicana was able to suppress the cell migration to the peritoneal cavity, in a time-dependent but not in a dose-dependent manner. The treatment of mice with C. mexicana extracts also decreased the xylene-induced ear edema, exerting strong inhibitory leukocyte migration elicited by zymosan into the air pouch. We concluded that administration of the extracts resulted in a reduction of cell migration to different sites as well as a decrease in edema formation induced by chemical irritants. This study demonstrates for the first time the anti-inflammatory effect of aqueous and methanolic extracts from the green marine algae Caulerpa mexicana.     

Hypoxic stress inhibits aerobic wound-induced resistance and activates hypoxic resistance to bacterial soft rot

Resistance to bacterial soft rot in potato tubers maintained aerobically was induced by wounding tubers 4 to 24 h prior to inoculation withErwinia carotovora subsp.carotovora. This wound-induced resistance phenomenon was blocked by hypoxic stress. An hypoxia-induced resistance mechanism also was detected: tubers acclimated to a hypoxic environment were resistant to rot when inoculated with aerobically grownE. c. subsp.carotovora and incubated in atmospheres made hypoxic by argon or nitrogen. With increased pretreatment, hypoxia-induced resistance approached the levels of resistance observed in tubers inoculated with aerobic-adapted bacteria and incubated aerobically. Hypoxia-adaptedE. c. subsp.carotovora overcame hypoxia-induced resistance.     

Water scarcity and inputs of nutrients from irrigation in olive groves of Crete Island,Greece

Water availability is an important factor for irrigated agriculture in the Mediterranean countries, because it affects significantly crop production. Surface soil samples were collected in Merambelo area located in Eastern Crete and analyzed. High values for exchangeable potassium and magnesium values were recorded and can be attributed to intensive fertilization and soil heredity factors. Groundwater quality based on two sampling campaigns performed during two irrigation periods. Three different scenarios were taken into account regarding the height of water application by means of irrigation. The contribution and the effects of nutrients and micronutrients from irrigation water to the soil was calculated, on the basis of the mean determined concentrations and the volume of applied irrigation. Significant variation was recorded in most soil properties, and these differences may be attributed to different mobility of nutrients, erosion factors, fertilization practices, and hydraulic soil properties.     

Effect of zinc ammonia acetate on germination and early seedling growth of three maize genotypes

Zinc ammonia acetate (ZAA) is marketed as an agricultural additive (ACA) and has been shown to increase the yield of corn (Zea mays L.). However, the response is sometime variable and the effective components and the mode of action are not known. To address these issues, the effect of four concentrations (0, 0.85, 8.5, and 85 ppm) of ZAA on laboratory germination and early seedling growth of three maize genotypes were evaluated. The ZAA at 0.85 and 8.5 ppm tended to increase the total seminal root length, and shoot and root dry weight of seedling in all genotypes. Hydroponic studies revealed that plant height and whole plant dry weight of 2‐week‐old seedlings tended to be increased with 0.85 and 8.5 ppm of ZAA in all genotypes compared to the control. The number of seminal and lateral root for all genotypes, and seminal root total length for two genotypes were significantly increased by ZAA at both 0.85 or 8.5 ppm. However, the high root:shoot ratio observed for ZAA‐treated seedlings was not due to increased root growth over shoot growth but resulted from a greater reduction in shoot growth at higher ZAA concentrations. The boron (B) content of the shoots of all genotypes had a positive linear response to increasing ZAA concentrations. Both 0.85 and 8.5 ppm of ZAA increased copper (Cu) and iron (Fe) contents of all genotypes. The calcium (Ca), potassium (K), magnesium (Mg), and phosphorus (P) concentrations were not significantly affected by ZAA treatments, although there was a trend toward an increase for some of these elements at both 0.85 and 8.5 ppm of ZAA. In a greenhouse test, plant height, leaf area, and shoot dry weight of 3‐week‐old seedlings of all genotypes were increased by ZAA at 0.85 and 8.5 ppm. Root volume was increased at both 0.85 and 8.5 ppm for one genotype. Considering the extremely low concentration of ZAA required to induce a plant response (0.85 or 8.5 ppm), some possible modes of action of ZAA are discussed.     

Genetic diversity in the Red wild einkorn: T. urartu Gandilyan (Poaceae: Triticeae)

Red wild einkorn, Triticum urartu, is increasingly being recognized as a source of genetic material for the improvement of wheat grain quality and for conferring resistance to various diseases such as Powdery Mildew and Leaf Rust resistance including the virulent race Ug99. Two hundred and two samples of T. urartu collected throughout much of its distribution were investigated by amplified restriction length polymorphism, AFLP? to estimate the genetic diversity within and among them. To infer the genetic structure of the populations the data were subjected to analyses of molecular variance, AMOVA. The analyses of the samples enabled us to assess the location(s) of the richest area(s) in genetic diversity of the species. This area is found in north-western Syria and the adjacent South Turkey. It was also found that the similarity among populations did not reflect on their geographic closeness.     

Improvement of phytoremediation effects with help of different fertilizer

Abstract

Phytoremediation is increasingly used to remediate metal contaminated soils. However, in order to provide technically efficient phytoremediation of contaminated sites the plant yield and metal uptake have to be enhanced dramatically. The aim of the study was to find appropriate combination of plant species and fertilizers capable of improving yields of the plants and stimulate a transfer of metals to more available to the plants forms. Wheat Triticum vulgare was used for the phytoremediation research. To increase yield of crops and enhance mobility of metals in the rhizosphere the soils were amended with three fertilizers (urea, horse manure, and “ispolin”). Short-term (36 d) vegetation test showed that concentrations of heavy metals in the plants grown in contaminated soil (from site 2) were significantly higher than those in the plants grown in clean soil (from site 1). Growth of wheat resulted in a decrease of Cd content in the soil. Amendment of the contaminated soil with urea enhanced the effect and the decrease of Cd concentration in the soil was more significant. The best effect was demonstrated after application of ispolin: concentrations of Cd, Cu, Pb, and Zn in the rhizosphere decreased 1.2–1.4 times as compared with those in the initial contaminated soil (the decrease was statistically significant).     

Horticultural Use of Copper-Based Fungicides Has Not Increased Copper Concentrations in Sediments in the Mid- and Upper Yarra Valley

The use of Cu-based fungicide can pose a risk to nearby surface water bodies due to the run-off of accumulated Cu from agricultural soils. In 2008, we conducted a reconnaissance survey of the presence and concentration of copper in sediments at 18 sites within the Yarra River Catchment, an important horticultural production system in south-eastern Australia. Observed Cu concentrations in sediment samples from the study sites (mean (95 % confidence interval) 12.0 (10.6–13.6)? mg/kg dry weight) were similar to the concentrations present in the samples from the reference sites (mean (95 % confidence interval) 12.0 (6.7–16.8)? mg/kg dry weight). The data on Cu and other metals in the sediments suggest that that there is unlikely to have been wide spread, diffuse, off-site transport of Cu from the soils of horticultural properties to nearby surface waterways in the Yarra River Catchment and that that observed sediment metal concentrations are unlikely to pose an ecological risk to sediment-dwelling organisms at the study sites.     

The response of properties of soil cropped with shell beans and treated with disinfectant and fertiliser during the plant growing season

Disinfectants and fertilisers exert strong impact on soil processes by affecting the structure and the activity of the soil microbial community. Most relevant studies examined these impacts independently, under laboratory conditions and without crop cover. In this study, we have monitored the response of soil chemical, microbial, and biochemical properties to disinfectant and fertiliser treatments in field plots cultivated with beans. The measured properties comprised microbial C and N, asparaginase, gultaminase, urease, and acid phosphomonoesterase activities and contents of organic N, organic C, inorganic N, and inorganic P. We ran four different treatments using different combinations of chemical (metham sodium) and biological disinfectant (a mixture of neem cake and essential oils) and fertilisers (NPK 8-16-24 and cow manure) in plots cultivated with shell beans, while the control soil was neither treated nor cropped with beans. The data were expressed as percentage (%RC) in relation to the control values. The disinfectant and fertiliser treatments had less impact on soil properties compared to bean crop growth (except for microbial C and N, and content of organic C). In comparison to the control, higher activities of urease and asparaginase and content of inorganic N were recorded in bean cropped plots at the stage of seedlings (June), while higher activities of acid phosphomonoesterase and glutaminase and content of organic N were recorded at the stage of plant flowering (August). In October, the values of all properties were higher in the control plots compared to the treated plots. The joint effect of disinfectants x fertilisers affected the response of content of organic C and N and extractable P and glutaminase activity. The %RC of the properties exhibited more negative values in plots treated with chemical disinfectant and chemical fertiliser than in the other treatments. We suggested that the response of soil properties to disinfectants and fertilisers were influenced by the growth of P. vulgaris.