Diversity of the Sheanut tree (Vitellaria paradoxa C.F. Gaertn.) in Ghana

The Sheanut tree (Vitellaria paradoxa C.F. Gaertn.) is highly valued for oil obtained from its seeds and frequently maintained in the semi-arid parklands of sub-Saharan Africa from Senegal to Uganda. Although variation has been noted for V. paradoxa subsp. paradoxa, few studies have been undertaken on patterns of phenotypic or genotypic diversity. Results are presented from 294 accessions collected in Ghana, using easily quantifiable morphological parameters. Productive mature trees varied from shrubby multi-stemmed individuals (height <5 m) to 30-m straight-boled trees with high compact canopies. The leaf lamina (tree mean ±% coefficient of variation of total mean) varied from 9.2 to 22.5 cm (±15.0%); seed length from 1.74 to 3.74 cm (±11.7%); and fat content from 29.1 to 61.9% of dry kernel weight (±9.4%). Clinal trends significantly correlated with location parameters that in turn related to environmental variation. Population variation of seed characteristics increased to the Northeast, perpendicular to the annual movement of the inter-tropical convergence zone. It is proposed that this is a consequence of past climatic changes, coupled with a lack of methodical selection for seed type when trees are maintained on agricultural land. Isozyme analysis revealed moderate to high levels of heterozygosity (He 0.2142) and high geneflow (Fst = 0.0124, Nm = 19.9), supporting results obtained from morphological studies. Isozyme and multivariate morphology analyses showed similar but weak geographical separation patterns.     

Critical limit of boron for maize (Zea mays L.) in red and lateritic soil of Jharkhand,India

ABSTRACT

To establish a critical limit in soils and plant, an experiment was conducted in red and lateritic soil (Alfisols) of farmer’s field in tribal-dominated Panchayat Kurum, Palkot block, Gumla district, Jharkhand, India. Based on the results of the field experiment, the critical limits were determined as 0.48, 0.50, 0.47, and 0.42 mg kg^?1 in the soil, respectively, for hot water, hot calcium chloride, salicylic acid, and ammonium acetate-extractable B, while a critical limit of 12.00 mg kg^?1 was observed in maize tissue using the graphical method. In an analysis of variance method, the critical limits of B in soils were found as 0.45, 0.54, 0.49, and 0.43 mg kg^?1 using hot water, hot calcium chloride, salicylic acid, and ammonium acetate extractants, respectively. Maize plants were highly responsive to B application where soil B level was below the critical limit (0.50 mg kg^?1). In a field experiment, grain yield of maize increased with increasing levels of B application, while soil application at 1.0 kg ha^?1 + two foliar application (at the knee and pre-flowering stages) of borax at 0.2% were showed significantly higher grain yield of the maize crop. The hot water, hot calcium chloride, salicylic acid, and ammonium acetate-extractable B were significantly and positively correlated with organic carbon and negatively correlated with the electrical conductivity of soils.     

Metal Accumulation and Functional Traits of Maianthemum bifolium (L.) F. W. Schmidt in Acid Beech Forests Differing with Pollution Level

Water, Air, & Soil Pollution - Silicon has been regarded as a promising technology to improve nutrient supply to plants. This study aimed to evaluate the influence of different nitrogen doses...     

Critical carbon inputs to maintain soil organic carbon stocks under long‐term finger‐millet (Eleusine coracana [L.] Gaertn.) cropping on Alfisols in semiarid tropical India

Enrichment of soil organic carbon (SOC) stocks through sequestration of atmospheric CO₂ in agricultural soils is important because of its impacts on adaptation to and mitigation of climate change while also improving crop productivity and sustainability. In a long‐term fertility experiment carried out over 27 y under semiarid climatic condition, we evaluated the impact of crop‐residue C inputs through rainfed fingermillet (Eleusine coracana [L.] Gaertn.) cropping, fertilization, and manuring on crop yield sustainability and SOC sequestration in a Alfisol soil profile up to a depth of 1 m and also derived the critical value of C inputs for maintenance of SOC. Five treatments, viz., control, farmyard manure (FYM) 10 Mg ha^–1, recommended dose of NPK (50 : 50 : 25 kg N, P₂O₅, K₂O ha^–1), FYM 10 Mg ha^–1 + 50% recommended dose of NPK, and FYM 10 Mg ha^–1 + 100% recommended dose of NPK imposed in a randomized block design replicated four times. Application of FYM alone or together with mineral fertilizer resulted in a higher C input and consequently built up a higher C stock. After 27 y, higher profile SOC stock (85.7 Mg ha^–1), C build up (35.0%), and C sequestration (15.4 Mg C ha^–1) was observed with the application of 10 Mg FYM ha^–1 along with recommended dose of mineral fertilizer and these were positively correlated with cumulative C input and well reflected in sustainable yield index (SYI). For sustenance of SOC level (zero change due to cropping) a minimum quantity of 1.13 Mg C is required to be added per hectare per annum as inputs. While the control lost C, the application of mineral fertilizer served to maintain the priori C stock. Thus, the application of FYM increased the C stock, an effect which was even enhanced by additional amendment of mineral fertilizer. We conclude that organic amendments contribute to C sequestration counteracting climate change and at the same time improve soil fertility in the semiarid regions of India resulting in higher and more stable yields.     

Phenotypic Variation of Agromorphological Traits of the Shea Tree, Vitellaria paradoxa C.F. Gaertn., in Mali

Forty-one shea tree populations were sampled, spanning the main climatic zones of Vitellaria paradoxa Gaertn. in Mali and 10–35 adult trees were chosen randomly in the agroforestry parklands of each area. A total of 12 morphological traits, related to tree morphology, fruit size and leaf form were measured. The variance components showed that variation among populations represented the smaller percentage of the total variation with most of the values varying between 15 and 30%. The repeatability coefficient was generally high for tree within populations with values ranging between 0.23 and 0.78. Although genetic correlations cannot be accurately estimated, due to difficulties in separation from environmental effects, the results indicate that there is a very low genetic relation between the three kinds of traits, i.e., between those related to tree, those related to leaf and those related to fruit. Leaf and fruit size traits were positively and significantly correlated with rainfall, although tree circumference was negatively correlated with rainfall and the significantly larger shea trees were noted in the drier areas – an observation thought linked to human management of the parklands. Soil drainage and parkland density, however, did not explain differences between populations for fruit traits. This study offers preliminary information for the development of a breeding population for a shea tree improvement programme. The value of repeatability, the low correlation between sets of traits and the distribution of variation, suggest that selection of many individual trees within a few populations, would allow capture of large genetic gain especially for fruit traits.     

Invasion of Alnus glutinosa (L.) Gaertn. in a former grazed meadow in relation to different grazing intensities

The invasion of Alnus glutinosa in a former grazed meadow in Hørret Wood near Århus (Eastern Jutland, Denmark) has been investigated. A dense Filipendula ulmaria vegetation, which has been developing since the grazing stopped, seems to prevent the establishment of seedlings of Alnus glutinosa, although the seeds are able to germinate in the spring, before the growth of Filipendula ulmaria starts. By reconstructing the development of four Alnus glutinosa thickets, it was concluded that moderate grazing favours the spread of Alnus glutinosa, whereas intensive grazing or cessation of grazing inhibits further invasion. The optimal grazing intensity for establishment of trees and bushes in meadows is discussed and related to the ‘floristic optimum’. Two situations in the management of meadows with grazing animals are proposed.     

Comparison of marker- and pedigree-based methods for estimating heritability in an agroforestry population of Vitellaria paradoxa C.F. Gaertn. (shea tree)

We implemented a regression-based method between pairwise relatedness estimated from markers and phenotypic similarity to estimate heritability of traits related to leaf size and morphology in a wild tree population (Vitellaria paradoxa C.F. Gaertn.: shea tree). We then compared the results with heritability estimated with a classical pedigree-based method. We tested both approaches in an agroforestry population of this tree species, a very important one and abundant in the Sudano-Sahelian zone of Africa. Twelve microsatellite loci were used to estimate pairwise relatedness after selection of estimator coefficients based on Monte Carlo simulation. The regression-based method applied to 200 individuals did not display a significant trend with physical distance between trees for relatedness as well as for actual variance of relatedness. In consequence, estimates of narrow-sense heritability of traits related to leaf size were not significant. The pedigree-based method using a progeny test with 39 families and 15 individuals per family from the same population showed high and significant estimates of narrow-sense heritability for the same traits (h² = 0.36–0.95), demonstrating a marked genetic variation within the population. This discrepancy between methods stresses the poor performance of the molecular marker-based method. This can be explained by the absence of fine-scale structure within the agroforestry population of shea trees, other parameters being consistent with recommended values. The regression-based method does not seem well adapted to the agroforestry tree population. New experiments in tree populations and theoretical approaches are needed to evaluate the real potential of the marker-based methods.     

Soil Quality Assessment under Restorative Soil Management Practices in Soybean (Glycine Max) after Six Years in Semi-Arid Tropical Black Lands of Central India

Vertisol soils of central India are heavy in texture, with high clay content and low organic matter. These soils are prone to degradation and the soil loss is due to poor management practices including excessive tillage. Based on a long-term study conducted for improving the quality of these soils, it was found that management practice such as low tillage (LT) + 4 t ha^?1 compost + herbicide (Hb) recorded significantly higher organic carbon (OC) (6.22 g kg^?1) and available N (188.5 kg ha^?1) compared to conventional tillage (CT) + recommended fertilizer (RF) + off-season tillage (OT) + hand weeding (HW) (OC: 4.71 g kg^?1, available nitrogen (N) (159.3 kg ha^?1). Among the physical soil quality parameters, mean weight diameter (MWD) was significantly higher under LT + 4 t ha^?1 straw + Hb (0.59 mm). The practice of LT + 4 t ha^?1 straw + HW recorded significantly higher microbial biomass carbon (MBC) (388.8 μg g^?1). The order of key indicators and their contribution towards soil quality was as follows: OC (29%) >, MBC (27%) > available zinc (Zn) (22%) > MWD (9%) > available boron (B) (8%), > dehydrogenase activity (DHA) (5%). The order of the best treatment which maintained soil quality index (SQI) values reasonably good (>1.5) was as follows: LT + 4t ha^?1 compost + HW (1.65) > LT + 4 t ha^?1 compost +Hb (1.60) > LT + 4t ha^?1 straw + HW (1.50). Hence, these treatments could be recommended to the farmers for maintaining higher soil quality in Vertisols under soybean system. Correlation studies revealed stronger relationship between key indicators like OC (R² = 0.627), MBC (R² = 0.884), available Zn (R² = 0.739) and DHA (R² = 0.604) with Relative Soil Quality Index (RSQI). The results of the present study would be highly useful to the researchers, farmers and land managers.     

Geochemical investigations on atmospheric precipitation in a medium-sized city (Göttingen,F.R.G.)

The concentration of 27 elements was investigated in 10 samples of precipitation from Göttingen, collected during May and September 1972. Göttingen is a non-industrial town of 130000 inhabitants, situated in a rural area, and essentially all the dissolved and undissolved material in rainwater is locally derived. Elemental concentrations in freshwater and shale are used for comparison with the dissolved elements in precipitation and the undissolved residue. The two phases have been separated after evaporation (concentration factors: 15 to 25-times). Phosphorous, Zn, Mn, and Pb are enriched in rainwater, while Si, Mg, Na, Ca, Cl, Fe, Hg, K, Li, and Al are depleted relative to average freshwater. Sulfate, Cd, and Cu have similar concentrations in rain and freshwater. The factors of accumulation between elements in residue and average shale are calculated after normalization to the Al-value. They are: ? 100 for Ag, Hg, Pb; between 10 and 20 for Zn, Cd, P, Cu, Mo; > 2 for Cr, Bi, Ni, Ba, Ti, V ; between 0.9 and 2.0 for Rb, K, Na, Li, Mg, Mn, Fe, Si, Ca; and 0.5 for Tl. The trace element accumulation is due to different anthropogenic sources: combustion of liquid petroleum fuels contributes to Ph, V, Ni, Mo, Hg, and sulfate, combustion of coal to Ba, sulfate, and chloride, and to the. readily volatile elements such as Hg, Cd, Tl, Bi, and Ag, combustion of refuse to Ag, Bi, Pb, Cd, Hg, Zn, Cr, Cu, Ba, and Mo in highly variable amounts. Fertilizers and road salts change the chemistry of soils and indirectly supply P, alkali and alkaline-earth metals to the fly dust. Modest industrial activity is responsible for high Cu and Cr concentrations. Despite the appreciable accumulation of some toxic elements, the precipitation in Göttingen is relatively pure compared to other areas. Favorable geologic conditions around Göttingen decrease the negative influences of potentially harmful airborne elements. The high carbonate content in the dust neutralizes the anthropogenic acids in the rainwater. Furthermore, the toxic trace elements are diluted, especially in the center of Göttingen, by a large amount of airborne dust.     

Boron Fertilization in Sunflower (Helianthus annuus L.) in an Inceptisol of West Bengal,India

This study is a synthesis of information on growth, yield, and boron-use efficiency of hybrid sunflower (cultivar Aditya) in an inceptisol (Gangetic alluvium) of West Bengal, India, under varied proportions of soil and foliar-applied boron. Foliar spray of boron (B), under all circumstances, performed better than soil application of B fertilizers with regard to sunflower seed and total dry-matter yield, B uptake, and B-use efficiencies, while 0.2 percent foliar B spray was associated with greatest B recoveries, B-use efficiencies, and sunflower seed yields in the experimental years.     

On-farm status of rice (Oryza sativa L.) genetic resources in Garhwal Himalaya of Uttarakhand,India

Rice (Oryza sativa L.) is one of the three major food crops of the world and India is the largest rice growing country accounting for about one-third of the world average under the crop. Rice is being cultivated in Northern India since ca 2000 BC as evident from archaeological studies. A total of 103 traditional varieties of rice collected from interior parts, during the study period. The present study was designed with the aim to document the rice diversity and its socio-economic and cultural importance for local farming communities of Garhwal Himalaya in Central Himalayan Region. For collection of information 324 households from 116 villages in the study area were sampled. The study revealed different agro-eco-niches of the study area, traditional processing pathways, socio-economic and cultural development, diversity available, factors responsible for erosion/replacement of diversity, aesthetic values and specialized food quality of local rice varieties etc. The number of rice varieties grown and available for cultivation in ten valleys of Garhwal Himalaya were documented so as these can be utilized and conserved for research and development in the future.     

Finger millet (Eleucine corocana L. Gaertn.) as a cover crop on weed control, growth and yield of soybean under different tillage systems

Adoption of conservation tillage systems has become more popular in recent years due to erosion control and economics. Weed control is often identified as the limiting factor in the adoption of such systems. Although herbicides are efficient and convenient, the need to reduce herbicide use has been emphasized. Cover crops have become a viable option in this context, but the contribution of cover crops to weed control has not been clearly defined. A 2-year field experiment compared minimum tillage (MT), no-tillage (NT) and conventional tillage (CT) for soybean [Glycine max (L.) Merr.] following paddy rice (Oryza sativa L.) with finger millet (Eleucine corocana L. Gaertn.) as a cover crop. Weed emergence, cover crop biomass, main crop growth and yield were observed. Finger millet effectively controlled weeds but total weed biomass was greater with NT than other tillage methods and seeding method had no effect at early stage of growth. Neither crop growth nor leaf chlorophyll content was affected by finger millet under given tillage treatments. Weed biomass was almost half under MT than NT. Finger millet was able to effectively manage weed biomass under MT to a level achieved under CT without a cover crop at the early stage of growth. Number of seeds per pod and 100 seed weight were not affected by tillage treatments but number of pods per square meter was significantly higher with row seeding than broadcast seeding of finger millet cover crop in 2002. The absence of finger millet under MT in 2003, significantly reduced soybean grain yield. Finger millet can be managed with a single mechanical suppression as a cover crop under MT with no yield reduction.     

Effect of Zn application on its uptake,distribution and concentration of Fe and Cu in finger millet [Eleusine coracana (L.) Gaertn.]

Zinc (Zn) malnutrition can be alleviated by increasing the dietary Zn intake through Zn biofortification of edible crops. Agronomic and genetic biofortification has been suggested as better option to increase the dietary Zn. In this study, we show considerable genetic variability for seed Zn concentration in six leading finger millet genotypes. External application of Zn resulted in improved Zn concentration in different plant parts; in particular there was significant increase in seed Zn concentration in all genotypes. Though genotypes GPU28 and INDAF5 showed differences in root and shoot Zn at vegetative stage but at reproductive stage there was no significant difference. Apart from that, Zn application increased the seed iron (Fe) concentration with no or minimal effect on copper (Cu) concentration.     

Aquatic Hazard Assessment of a Contaminated Surficial Aquifer Discharge into the Bush River,Maryland (U.S.A.)

An aquatic hazard assessment of contaminatedgroundwater in a surficial aquifer was conducted at Beach Pointwhich is located in the Edgewood Area of the U.S. Army Garrison,Aberdeen Proving Ground, Maryland. Toxicity was detected atvarious groundwater concentrations by seven of 10 toxicity testsystems exposed to a mixture of heavy metals and chlorinatedaliphatic hydrocarbons. When estimated maximum acceptabletoxicant concentrations (MATC) were established, the data foralgae, invertebrates, and fish suggested that the groundwaterwould not be harmful at a concentration of 10% groundwater byvolume. Likewise, no genotoxicity (Ames and SEC assays),development toxicity (FETAX), or chronic histopathology (9-monthfish test) occurred at 10% groundwater by volume.Near-field (ULINE model) and far-field (dye-tracer model)screening level dilution models were run to estimate the dilutionof the groundwater discharge plume from Beach Point into the BushRiver. The groundwater was considered to be a potentiallyexcessive hazardous material to the biota in the Bush River whena number of conservative assumptions regarding contaminantdistribution and discharge rate of the aquifer were used in thehazard assessment. By modeling the groundwater emanating fromBeach Point as the dilution of a discharge from a line diffuser,the potential water quality impacts were judged to be minimal ifState of Maryland surface water discharge criteria for a mixingzone were used for the discharge of groundwater to the Bush River.     

Impact of Sewage Sludge Application on the Long-Term Nutrient Balance in Acid Soils of Scots Pine (Pinus Sylvestris,L.) Forests

The objective of the investigation was to determine the effectsof sewage sludge application on nutrient concentrations in soil and plant biomass fractions in Scots pine forests (Pinus sylvestris, L.), situated on sandy soils with low pH, in a south to north temperature gradient in Sweden. Twenty tons dw ha^-1 of sewage sludge was applied in 50 to 60 yr old pine forests at foursites from Brösarp in South Sweden to Jukkasjärvi in thenorthern parts of the country.Application of 20 ton dw ha^-1 of sewage sludge significantlyincreased the concentrations of extractable N, P, K, Ca, Mg and Na, in both the mor layer and in the upper 10 cm of the mineral soil. Three years after sludge application K concentrations were only significantly increased in the upper 10 cm of the mineral soil. After 11 yr the concentrations of P were still at the samelevel in the mor layer as after three years. The concentrations of Ca, Mg and Na had slightly decreased only in the mor layer. There was, in most cases, a statistically significant positive correlation between the amount of applied sludge and nutrientconcentrations in the soil, as well as in pine needles and in leaves of Vaccinium vitis-idaea.In all sites, Mg concentrations in the mor layer was positivelyand significantly correlated with Mg concentrations in current-year pine needles. Similarly, concentrations of Ca, Mg,and P in the mor layer were correlated with concentrations of these elements in current-year shorts of Vaccinium vitis-idaea.     

Assessment of Atmospheric Heavy Metals by Moss Monitoring with Isothecium Stoloniferum Brid. in the Fraser Valley, B.C., Canada

The atmospheric heavy metal pollution of the Fraser Valley, B.C., Canada was assessed in 1993 by analyzing 62 samples of the common woodland moss Isothecium stoloniferum for lead, cadmium, nickel, zinc, chromium, and manganese. The latter two metals did not show a distinct regional distribution, but lead, cadmium, nickel, and zinc showed distinct pattern along a west-east gradient. High values were found in the metropolitan Vancouver area, located in the west of the study region. Significantly lower values were recorded for mosses from the eastern more rural areas of the Fraser Valley. Metal pollutants are likely to be contained close to their emission sources by alternating south-east, north-west winds. Highest values overall were found in the North Shore Mountains, adjacent to Vancouver. This was related to higher precipitation and short range pollutant transport from the industrialized, heavily populated areas in the floodplain of the Fraser River.     

Effect of manures and inorganic fertilizers on growth,yield, and essential oil of damask rose (Rosa damascena Mill.) and chemical properties of soil in western Himalayas

A field experiment was conducted to study different manures and inorganic fertilizers effect on damask rose during 2008–2012. The rose essential oil (EO) was obtained by hydro distillation in Clevenger type apparatus and the components in the rose oil were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). Application of 90:80:90 kg nitrogen: phosphorus: potassium (NPK) ha^?1 outshine all other treatments and recorded significantly higher flower and oil yield as compared to control. EO yield was also significantly correlated with flower yield plant^?1, number of flowers plant,^?1 and flower yield ha^?1. The higher percentage of citronellol+nerol was obtained by the application of 120:40:90 kg NPK ha^?1. Geraniol (26.2%) was maximum when the plants were fertilized with 90:40:90 kg NPK ha^?1. Citronellol+nerol/geraniol ratio was also high in fertilized plots. Furthermore, manure application resulted in a marked improvement in chemical properties (pH, percent organic carbon, available N, P, and K) of the soil.     

Water,nutrient and pollutant budgets in damaged Norway spruce stands in NE-Bavaria (F.R.G.) and their changes after different fertilization treatments

Water budgets and ecosystem balances of the main nutrients and pollutants were calculated in two Norway spruce forests at different states of decline in the Fichtelgebirge (F.R.G.) from summer 1984 through summer 1986. For that purpose, samples of precipitation, throughfall, litter seepage and soil solution were gathered weekly. Fluxes of main cations and anions were calculated by multiplying water fluxes through the different compartments with the appropriate ion concentrations. Both spruce stands are characterized by a sufficient water supply throughout the investigation period caused by high annual precipitation. Only in dry periods drastical restriction of plant available water may endanger those spruces growing on very stony podzols and cambisols. The calculation of deposition fluxes differentiates the damaged and the apparently healthy spruce stand. Input of SO₂ and H⁺ as well as canopy buffering and K-leaching of the canopies are significantly higher in the damaged spruce stand than in the healthy one. Additionally, the exchangeable base cation content of the soil on the damaged site is nearly exhausted and therefore buffering capacity in the soil differs from those of the healthy site. There was a low increase of N0₃-leaching with seepage after the fertilization with high amounts of lime.