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Weeds are a major problem in cropping systems and in urban areas. The aim of this study was to assess the effectiveness of organic mulching with olive leaves and almond hulls to control weeds in fennel (Foeniculum vulgare Mill.) and in flower beds (urban areas). A 3-cm thick layer of olive leaves or almond hulls was applied as mulching material in fennel. Control consisted of both an unmulched treatment and a weed free control. Moreover, in a flower bed of a railway station, plots mulched with 3 cm layer of olive leaves and almond hulls were compared with an unmulched treatment. Weed infestation was evaluated and the weights of the whole plant and of the marketable part of fennel (grumolo) measured. Mulching with olive leaves and almond hulls reduced weed infestation in both vegetable crop and flower beds. However, olive leaves reduced the weights of the whole plant and of the grumolo. The adoption of almond hulls and olive leaves as organic mulches could be an effective strategy for weed control. Further investigations should be carried out to assess whether the effectiveness of these mulching materials is mainly due to a mechanical activity or allelopathic compounds also play a significant role in weed suppression. [ABSTRACT FROM AUTHOR]

In the recent years, the use of sewage water for irrigation has attracted the attention of arid and semi-arid countries where the availability of fresh water is poor. Despite the potential use of sewage water in crop irrigation as effective and sustainable strategy, the environmental and human risks behind this use need to be deeply investigated. In this regard, an experiment was carried out under field conditions in Nursery, University College of Agriculture Sargodha, to evaluate the possible health risks of undesirable metals in wheat grains. Wheat variety Sarang was cultivated and irrigated with different combinations of ground (GW) and sewage water (SW). The concentrations of heavy metals (Cr, Cd, Ni, and Pb) and trace elements (Cu, Zn, and Fe) in wheat grains as well as in soil were determined. Moreover, the pollution load index (PLI), accumulation factor (AF), daily intake of metals (DIM), and health risk index (HRI) were calculated. Results showed that the concentration trend of heavy metals was Pb

Bioavailability of heavy metals was determined from soil to plant. The levels of seven different heavy metals viz. lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni), zinc (Zn), copper (Cu), and arsenic (As) were analyzed in spinach. Spinach showed high level of arsenic. It is concluded that the vegetables grown in this region especially leafy ones are highly contaminated with Pb, Cd, and Ni and can cause health hazard for human consumption. Therefore, to reduce the health risk and the extent of heavy metal contamination, steps must be taken for efficient treatment of sewage. [ABSTRACT FROM AUTHOR]

In this study, we investigated metal and metalloid (Pb, Mn, Ni, Co, Cu, Cd, Zn, Se, Mo, Fe, As and Cr) concentrations in brinjal (Solanum melongena L.) as well as at two different cultivated sites in the vicinity of Sargodha. At both study sites (I and II), mean concentrations of As and Cd in soil and Mn, Ni, Cu (23.9, 28.9), Zn (61.2, 74.7), Mo (16.1, 18.3), and Cd (0.82, 1.11) in S. melongena were above the permissible limits as given by USEPA and WHO, respectively. The results revealed significant correlations between soil and vegetables for metals viz. Mn, Co, Ni, Zn, Cd and Pb. The trend of bioconcentration factor (BCF) at both sites was: 0.05-295.6 with higher BCF was observed for Cr (229.4, 295.6). High pollution load index at site-II indicated that this vegetable may cause toxic effects in humans due to high metal accumulation in the consumable parts of the vegetable. It is concluded that more effective controls should be taken to reduce pollution in this study area. [ABSTRACT FROM AUTHOR]

The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks. [ABSTRACT FROM PUBLISHER]

Accumulation of metals and metalloids was assessed in a vegetable crop of cabbage (Brassica oleracea L.) irrigated with domestic wastewater in two different sites of a peri-urban areas of Khushab City, Pakistan. From findings, the levels of different metals and metalloids such as Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd and Pb were higher at site-II than those found at site-I. At both sites, the concentrations of metals and metalloids in the vegetable samples irrigated with canal and sewage water were observed below the permissible levels except for Mn, Ni, Zn, Mo and Cd. At both sites, the transfer factor ranged from 0.037- 241.0 mg kg-1 with Cr having the highest transfer factor. The metal pollution index in soil resulted in the following order: Cd > Ni > Se > Mo > Mn > Co > Zn > Cr > Pb > Fe > Cu > As, respectively. The results from this study suggested that significant differences existed in the metals concentrations among the analyzed vegetables and that soil accumulates high concentration of heavy metals to the vegetables when irrigated with wastewater. Thus, farmers should be well-informed on problems associated with excessive usage of fertilizers as well as irrigating the crops with waste and all sorts of polluted water and the needs to grow crops with safe levels of heavy metals. [ABSTRACT FROM AUTHOR]

Plants adopt different strategies in response to seasonal variations in their natural biotype. In this study, the responses of seasonal changes on the organic osmolyte contents, ionic homoeostasis, osmotic potential and succulence of native chenopods in a salt marsh of Egypt were studied. Five halophytic species of the chenopodiaceae were collected during the rainy and dry season: Atriplex halimus L., Halocnemum strobilaceum (Pall.), Salicornia fruticosa (L.), Suaeda pruinosa (Lange) and Arthrocnemum macrostachyum (Moric). Results showed that plants employ an osmoconformer strategy via species specificity of response to seasonal variations. The total ions accumulation in all species was higher during the rainy season compared with the dry season. In particular, during rainy season, A. halimus resulted the higher accumulator species, followed by H. strobilaceum. Conversely, S. fruticosa, S. pruinosa and A. macrostachyum were defined as low-accumulator species. In each studied species, the effective salinity, biological absorption coefficient as well as leaf succulence were higher during the rainy season. In conclusion, the present study have pointed out the importance that should be accorded with the development of research directed towards agronomic aspects for the uses of halophytic chenopodiaceae in salt marsh. Further, data obtained indicate that the ions accumulator species should be considered for use in phytoremediation of degraded saline lands. [ABSTRACT FROM AUTHOR]

The shortage of forage in arid areas is an important concern and it leads us to explore alternative options as nonconventional feed resources. Among potential forage species, samples ofRetama raetam (R. raetam)were collected from six different locations representing four habitat types in two diverse phytogeographical regions in Egypt during the summer and winter seasons. Soil characteristics, growth performance, and nutritional traits ofR. raetamwere evaluated to assess the potential value of this legume as an alternative forage source in the Mediterranean ecosystem. Data showed that soil texture across the study sites had sandy, loamy, and clayey textures, whereas pH ranged from neutral to alkaline and organic carbon was low at all sites. Growth and production ofR. raetamwere significantly affected by seasonal variation in rainfall and, based on our study results, this effect was more important than specific site property variations such as soil texture and organic matter contents. Moreover, data indicate thatR. raetamhad wide ecological amplitude and growth performance as a function of site and season. Nutritional value ofR. raetamwas high enough to meet the nutrient requirements of several different grazing animals. Comparing theR. raetamnutritional value with those of the other wild plants, it can be concluded thatR. raetamhas strong potential as forage crop with valuable nutritional quality for browsing animals. Moreover,R. raetammay represent an alternative feedstuff to the conventional forage and a promising substitute fodder in Mediterranean ecosystem. [ABSTRACT FROM AUTHOR]

Intercropping systems could be a potential source of nutrient-rich forage production in cool climates on podzolic soils common in boreal ecosystems. In this study, we evaluated the effects of corn–soybean intercropping (IC) on the nutritional quality of forage. Two silage corn varieties were cultivated as monocropping (MC) or were intercropped with three forage soybean varieties using a randomized complete block design. IC significantly increased the crude protein (22%) and decreased the acid detergent (14%) and neutral detergent (6%) fibers. Forage net energy, total digestible nutrients, ash, dry matter intake, digestible dry matter and relative feed value were also significantly increased (p ≤ 0.05) in the IC treatments compared to corn MC. The macro and micro nutrients were higher in IC than corn MC. Intercropping increased the omega 3 fatty acid (FA) contents (67%) compared to corn MC. IC also increased the active microbial community in the plant root zone, which may contribute to the improvement in forage nutritional quality because the active soil microbial community composition showed significant correlations with soluble sugars, soluble proteins and potassium contents of the forage. These results demonstrate that corn–soybean IC could be a suitable cropping system to increase the nutritional quality of forage cultivated on podzols in boreal climates. The resultant forage has the potential to be a source of high-value animal feed for livestock production in cool climate regions of the world. [ABSTRACT FROM AUTHOR]

The interactive effects of indole acetic acid (IAA) or salicylic acid (SA) (0.5 and 0.1 mM, respectively) as shoot spraying on NaCl stressed wheat (Triticum aestivum L.) plant organs grown in experimental pots under different salinity levels (0, 50, 100, 150 and 200 mM NaCl, respectively) were studied. The antioxidant enzymes as catalase (CAT), peroxidase (PX), and ascorbate peroxidase (APX), photosynthetic pigments, reducing sugars, proteins, amino acids (AA), and proline (Prol) contents in spike, shoot and root of salt-stressed plants were the most affected parameters, specially at high salinity levels (150 and 200 mM NaCl). Treatments with 0.5 mM of IAA or 0.1 mM of SA on stressed wheat organs mitigated the detrimental effect of NaCl. Phytohormones improved salt tolerance in wheat organs activating antioxidant enzymes, increasing photosynthetic pigments and enhancing the accumulation of non toxic metabolites. The magnitude of increase was more pronounced in SA than in IAA treated plants, and the spike was the most accumulator organ of non toxic metabolites compared to shoot and root. Finally, SA and/or IAA treatments prevent the negative effects of salt stressed wheat and these could be adopted as a potential growth regulator or antioxidant to improve wheat growth under moderate salt levels. [ABSTRACT FROM AUTHOR]