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Soil Application (soil + application)
Selected AbstractsEffects of bio-pesticides on Eretmocerus warrae (Hym., Aphelinidae), a parasitoid of Bemisia tabaci (Hom., Aleyrodidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2008P. Kumar Abstract The sweet potato whitefly Bemisia tabaci (WF) can be controlled by two commercial neem products, NeemAzal-T/S® (1% azadirachtin) for foliar application, and NeemAzal-U (17% azadirachtin) for soil application, alongwith two biorational products of microbial origin, Abamectin (avermectin) and Success® (spinosad). Side effects of these products were tested in a laboratory bioassay against a native aphelinid, Eretmocerus warrae (EW). Eggs and early larval instars of the parasitoid, commonly found outside the host body, were highly susceptible to foliar spray of neem with only 8%, 18% and 55% emergences of adults from treated eggs. larval and pupal stages respectively at recommended dose-rates of 5 ml/l and 1%, 8% and 40% at twice recommend dose-rate (10 ml/l). Soil application with NeemAzal-U marginally affected EW. At highest tested dose-rate of 3.0 g/l, 46%, 64% and 81% emergence was recorded after treatement of plants harbouring WF parasitized by egg, larval and pupal stages of EW respectively. In contrast to neem application, Success® and Abamectin caused high mortality in development stages of the parasitoids. In particular, abamectin was highly toxic to the parasitoids with less than 1% emergence from either of the three development stages if treated with 1,2 ml/l. [source] Development of emulsion from rhizobial fermented starch industry wastewater for application as Medicago sativa seed coatENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2010Rojan Pappy John Abstract Starch industry wastewater was efficiently employed for the production of Sinorhizobium meliloti and the concentrated culture was used for the development of a biofertilizer formulation. Tween-80 (0.02,g/L) acted as the best emulsifier for a Sinorhizobium,canola oil emulsion. The stability of the emulsion and survival of the organism was enhanced by supplementation of xanthan gum at pH 8. The refrigerated condition was most favorable for stability and survival of the microorganism. The survival of microorganism at 4±1°C was 2.78×1010 and 2.01×1010,CFU (colony forming unit)/mL on storage for 1 and 2 months, respectively. The values were higher than the prescribed cell count (×103,CFU/mL) for field application. At 40°C, the survival of bacteria reduced from 3×1010,CFU/mL to 8.1×109 and 8.8×106,CFU/mL in 1 and 2 months, respectively. Emulsion-coated seed was incubated at different temperatures and a cell count of 105,CFU/seed was observed after 2 months of storage at 4°C, which was equal to the highest level of the described requirement (103,105,CFU/seed). Emulsion supplemented with xanthan gum improved the shelf-life under optimized conditions (Sinorhizobium concentrate,,,canola oil (1:1) emulsion with 0.02,g/L Tween-80; storage at pH 8 and temperature 4±1°C) and this emulsion with the required cell count and prolonged viability was used for the pre-inoculation of seed or for in situ soil application. [source] Effect of cotton nitrogen fertilization on Bemisia argentifolii populations and honeydew productionENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2001J.L. Bi Abstract The impact of nitrogen fertilization on cotton plants, Gossypium hirsutum L., silverleaf whitefly, Bemisia argentifolii Bellows & Perring, population dynamics and honeydew production were investigated in the field at Riverside, California, USA. Treatments were soil applications of 0, 112, 168 and 224 kg nitrogen per hectare, and a soil application of 112 kg of nitrogen plus a foliar application of 17 kg nitrogen per hectare. Increased numbers of both adult and immature whiteflies occurred during population peaks with increasing amounts of applied nitrogen. Higher numbers of whiteflies resulted in increased levels of honeydew. Increasing plant nitrogen also enhanced cotton foliar photosynthetic rates and stomatal conductance, and altered concentrations of glucose, fructose and sucrose in cotton petioles. However, at our treatment levels nitrogen had no effect on seedcotton yield. Petiole glucose levels were significantly correlated with numbers of whitefly adults on leaves during their peak populations. Significant correlations between whitefly numbers and other cotton physiological parameters occurred on only a few sampling dates. [source] Effects of bio-pesticides on Eretmocerus warrae (Hym., Aphelinidae), a parasitoid of Bemisia tabaci (Hom., Aleyrodidae)JOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2008P. Kumar Abstract The sweet potato whitefly Bemisia tabaci (WF) can be controlled by two commercial neem products, NeemAzal-T/S® (1% azadirachtin) for foliar application, and NeemAzal-U (17% azadirachtin) for soil application, alongwith two biorational products of microbial origin, Abamectin (avermectin) and Success® (spinosad). Side effects of these products were tested in a laboratory bioassay against a native aphelinid, Eretmocerus warrae (EW). Eggs and early larval instars of the parasitoid, commonly found outside the host body, were highly susceptible to foliar spray of neem with only 8%, 18% and 55% emergences of adults from treated eggs. larval and pupal stages respectively at recommended dose-rates of 5 ml/l and 1%, 8% and 40% at twice recommend dose-rate (10 ml/l). Soil application with NeemAzal-U marginally affected EW. At highest tested dose-rate of 3.0 g/l, 46%, 64% and 81% emergence was recorded after treatement of plants harbouring WF parasitized by egg, larval and pupal stages of EW respectively. In contrast to neem application, Success® and Abamectin caused high mortality in development stages of the parasitoids. In particular, abamectin was highly toxic to the parasitoids with less than 1% emergence from either of the three development stages if treated with 1,2 ml/l. [source] Leaching of heavy metals and nutrients from calcareous sandy-loam soil receiving municipal solid sewage sludgeJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2010Mohsen Jalali Abstract Leaching column experiments were conducted to determine the degree of mobility of heavy metals (HMs) and nutrients after the addition of municipal solid sewage sludge (MSS) in a sandy-loam soil. Treatments were (1) soil application of low metal content MSS, (2) soil application of metal-enriched municipal solid sewage sludge (EMSS), and (3) control. The MSS application represented a dose of 200 Mg dry weight (dw) ha,1. Soil columns were incubated at room temperature for 15 d and were irrigated daily with distilled water to make a total of 557,mm. Leachates were collected and analyzed for HMs and nutrients. The Ni and Pb added to soil via MSS and EMSS were found to be leached through the 20,cm columns of calcareous sandy soil although Ni and Pb concentrations in the percolate were small relative to the total amounts of metals applied. Losses of K+ from the EMSS, MSS, and control were 92.5, 82.0, and 52.5,kg ha,1, respectively. Losses of Mg2+ were in the range from 104.4 (control treatment) to 295.2,kg ha,1 (EMSS), while the loss of Ca2+ was in the range from 265.0 (control treatment) to 568.2,kg ha,1 (EMSS). The results showed that the amounts of P leached from EMSS (3.02,kg ha,1) and MSS (2.97,kg,1 ha,1) were significantly larger than those from the control treatment (1.54,kg ha,1). The geochemical code Visual MINTEQ was used to calculate saturation indices. Leaching of P in different treatments was controlled by rate-limited dissolution of hydroxyapatite, ,-tri-Ca phosphate, and octa-Ca phosphate. The results indicate that application of MSS to a sandy soil, at the loading rate used in this study, may pose a risk in terms of groundwater contamination with Ni, Pb, and the studied nutrients. [source] Sodium removal from a calcareous saline,sodic soil through leaching and plant uptake during phytoremediationLAND DEGRADATION AND DEVELOPMENT, Issue 3 2003M. Qadir Abstract Saline,sodic and sodic soils are characterized by the occurrence of sodium (Na+) to levels that can adversely affect several soil properties and growth of most crops. As a potential substitute of cost-intensive chemical amelioration, phytoremediation of such soils has emerged as an efficient and low-cost strategy. This plant-assisted amelioration involves cultivation of certain plant species that can withstand ambient soil salinity and sodicity levels. It relies on enhanced dissolution of native calcite within the root zone to provide adequate Ca2+ for the Na+Ca2+ exchange at the cation exchange sites. There is a lack of information for the Na+ balance in terms of removal from saline,sodic soils through plant uptake and leaching during the phytoremediation process. We carried out a lysimeter experiment on a calcareous saline,sodic soil [pH of saturated soil paste (pHs),=,7.2, electrical conductivity of the saturated paste extract (ECe),=,4.9,dS,m,1, sodium adsorption ratio (SAR),=,15.9, CaCO3,=,50,g,kg,1]. There were three treatments: (1) control (without application of a chemical amendment or crop cultivation), (2) soil application of gypsum according to the gypsum requirement of the soil and (3) planting of alfalfa (Medicago sativa L.) as a phytoremediation crop. The efficiency of treatments for soluble salt and Na+ removal from the soil was in the order: gypsum,,,alfalfa,>,control. In the phytoremediation treatment, the amount of Na+ removed from the soil through leaching was found to be the principal cause of reduction in salinity and sodicity. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effect of cotton nitrogen fertilization on Bemisia argentifolii populations and honeydew productionENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2001J.L. Bi Abstract The impact of nitrogen fertilization on cotton plants, Gossypium hirsutum L., silverleaf whitefly, Bemisia argentifolii Bellows & Perring, population dynamics and honeydew production were investigated in the field at Riverside, California, USA. Treatments were soil applications of 0, 112, 168 and 224 kg nitrogen per hectare, and a soil application of 112 kg of nitrogen plus a foliar application of 17 kg nitrogen per hectare. Increased numbers of both adult and immature whiteflies occurred during population peaks with increasing amounts of applied nitrogen. Higher numbers of whiteflies resulted in increased levels of honeydew. Increasing plant nitrogen also enhanced cotton foliar photosynthetic rates and stomatal conductance, and altered concentrations of glucose, fructose and sucrose in cotton petioles. However, at our treatment levels nitrogen had no effect on seedcotton yield. Petiole glucose levels were significantly correlated with numbers of whitefly adults on leaves during their peak populations. Significant correlations between whitefly numbers and other cotton physiological parameters occurred on only a few sampling dates. [source] | |||||||||||||