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Articles published from 1984-2014.

Description

Publishes original articles and commentaries on research in the fields of fundamental and applied soil and plant science. Original research papers, short communications including germplasm registrations, relevant book reviews, commentaries on papers recently published and, exceptionally, review articles will be considered for publication in the Journal. Manuscripts considered will address aspects of: Agronomical and Horticultural research including breeding and genetics, cultivar evaluation, management, nutrition, physiology, production, and quality; Soil Science research including biology, chemistry, classification, fertility, mineralogy, pedology and hydropedology, physics, and soil and land evaluation of agricultural and urban ecosystems; Weed Science research including biological control agents, biology, ecology, genetics, herbicide resistance and herbicide-resistant crops, and physiology and molecular action of herbicides and plant growth regulators; Agro-climatology; Agro-ecology; Forage, Pasture and Turfgrass science including production and utilisation; Plant and Soil Systems Modelling; Plant–Microbe Interactions; Plant–Pest Interactions; and Plant–Soil Relationships.

latest article added on October 2013

ArticleFirst AuthorPublished
Effects of liming and inorganic fertiliser application on soil properties and maize growth and yield in rural agriculture in the Mbizana area, Eastern Cape province, South AfricaBeukes, DJ2012

Effects of liming and inorganic fertiliser application on soil properties and maize growth and yield in rural agriculture in the Mbizana area, Eastern Cape province, South Africa

Keywords

amelioration, infertility, maize yield, nutrient efficiency, soil acidity

Abstract

A five-year study was conducted to assess the seasonal and medium-term effects of liming and fertilisation of an acid clay loam topsoil on soil properties and on the growth and yield of maize under dry land. Treatments consisted of a control, a once-off application of three levels of dolomitic lime, annual application of two levels of inorganic fertiliser, and three levels of chicken manure. A no-till practice was used with hand planting and fertiliser application. Leaf and soil sampling, as well as harvesting, were performed and analyses done. Soil extractable acidity, acid saturation and leaf Mn and K were reduced significantly, whereas soil pH, soil and leaf P, Ca and Mg increased significantly with an increase in lime application. Liming had no clear effect on soil K, maize leaf N, Cu, Fe and Zn, or on maize grain yield. The higher commercial fertiliser level significantly increased soil P, K and Ca, as well as leaf N, P, K, Cu, Mn and grain yield, compared to the traditional level. These results emphasise the longevity of liming application and that low soil fertility, followed by soil acidity, are the primary factors limiting soil productivity in the study area.

Authors

Beukes, DJ, Fyfield, TP, Jezile, GG and Mapumulo, TC

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.740506

This article contributed by:

Original

Biomass production, weed suppression, nitrogen and phosphorus uptake in white oat (Avena sativa L.) and grazing vetch (Vicia dasycarpa L.) cover crop bicultures under an irrigated no-till systemChiduza, C2012

Biomass production, weed suppression, nitrogen and phosphorus uptake in white oat (Avena sativa L.) and grazing vetch (Vicia dasycarpa L.) cover crop bicultures under an irrigated no-till system

Keywords

Conservation agriculture, cover crop mixtures, no-till farming, soil cover, weed species count

Abstract

Cultivation of a multipurpose cover crop is of interest to Eastern Cape farmers experiencing soil infertility and weed pressures. The objective of the study was to investigate effects of oat–vetch bicultures on biomass production, weed suppression, and nitrogen (N) and phosphorus (P) uptake. The study was conducted between 2009 and 2010. Treatments included 90% oat + 10% vetch, 70% oat + 30% vetch, 50% oat + 50% vetch, 100% vetch, 100% oat and a weedy fallow as control. Bicultured cover crops had significantly (p < 0.05) higher biomass compared to sole vetch in both seasons but reduced biomass compared to sole oat only in 2010. Weed suppression increased with an increase in biomass. Weedy fallow had the least weed suppression (p < 0.05) at all sampling times, whereas sole oat provided the best early weed control compared to the rest of treatments. Nitrogen uptake by sole vetch was comparable to 50% oat + 50% vetch and 70% oat + 30% vetch. Phosphorus uptake differed only in the 2010 season and 90% oat + 10% vetch, 70% oat + 30% vetch and sole vetch had the best uptake. Weedy fallow had the least N and P uptake during the two seasons. Bicultures can be used for improved biomass, weed suppression, and N and P uptake with potential of alleviating soil degradation effects in the Eastern Cape province.

Authors

Chiduza, C, Muchaonyerwa, P and Muzangwa, L

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.741719

This article contributed by:

Original

Family selection gains for quality traits among South African sugarcane breeding populationsZhou, MM2012

Family selection gains for quality traits among South African sugarcane breeding populations

Keywords

broad-sense heritability, covariance parameters, selection gains, sugarcane

Abstract

In sugarcane breeding, family selection has been shown to produce larger gains than individual plant selection. During family selection, whole families of seedlings are selected or rejected based on data derived from replicated family plots. The objective of this study was to determine predicted family selection gains and evaluate their implications for variety improvement in terms of quality traits among sugarcane breeding populations of the South African Sugarcane Research Institute's regional breeding programmes. The data was collected from seven breeding populations and analysed using the Statistical Analysis System (SAS). All the quality traits showed highly significant family effects variance components. There were consistent increases in heritability and gains to selection with advancing population series indicating benefits from indirect recurrent selection. Brix % cane, because it costs less to measure, could be used to evaluate within family variability. The B, C, U and F populations produced larger and more consistent selection gains than K, T and S. Recurrent selection could be used to enhance breeding for quality traits.

Authors

Zhou, MM and Lichakane, ML

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.743606

This article contributed by:

Original

Yield and quality response of rose geranium (Pelargonium graveolens L.) to sulphur and phosphorus applicationSedibe, MM2012

Yield and quality response of rose geranium (Pelargonium graveolens L.) to sulphur and phosphorus application

Keywords

oil quality, phosphorus, rose geranium, sulphur

Abstract

Sulphur and phosphorus are essential plant macronutrients. Sulphur is involved in the formation of chlorophyll, activation of enzymes and is part of coenzyme A. Phosphorus forms part of the structure of nucleic acids and phospholipids. Two separate studies were conducted to determine the effects of sulphur and phosphorus levels in nutrient solutions on yield and quality of hydroponically grown rose geranium as well as setting standards of sulphur and phosphorus amounts to be used in the production process. The effect of four levels of sulphur (0.36, 1.90, 3.44 and 4.98 mmol l−1) was investigated in the first study and in the second study four levels of phosphorus (0.1, 0.8, 1.5 and 2.2 mmol l−1) were also investigated. All treatments were assigned in a completely randomised block design with five replicates. The results of the first study showed a significant effect of sulphur on the number of branches, plant height and foliar fresh mass. Foliar fresh mass and oil yield peaked at the 3.44 mmol l−1 concentration. The second study showed that plant height and the number of branches was not affected significantly by phosphorus, but foliar mineral phosphorus, magnesium and potassium were affected. Oil yield of rose geranium increased linearly with increased phosphorus concentrations. Both the guaia-69-diene content and the citronellol:geraniol ratio were greater at the highest phosphorus level, which indicated that oil quality can be enhanced by using relatively high phosphorus concentrations in nutrient solutions.

Authors

Sedibe, MM and Allemann, J

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.744108

This article contributed by:

Original

Control measures for the encroacher shrub Seriphium plumosumSnyman, HA2012

Control measures for the encroacher shrub Seriphium plumosum

Keywords

bankrupt bush, Molopo, Seriphium plumosum (Stoebe vulgaris), shrub encroachment, slangbos, vaalbos

Abstract

Seriphium plumosum encroachment in South Africa has converted extensive areas of grassland into less productive shrubland–grassland, but its control is not being seriously addressed at present. Therefore, the short-term response of S. plumosum to different applications of nitrogen (N), phosphate (P), lime, sodium chloride (NaCl) and a soil-applied suspension herbicide, Molopo (active ingredient tebuthiuron), was examined. The lime and P-fertiliser treatments lead to no deaths of S. plumosum for any of the concentrations. The smaller the shrubs, the more sensitive they were to both N and NaCl applications. The minimum N-fertiliser applications of 30, 60, 120, 1 000 and 2 000 kg ha−1 were responsible for 100% death of shrubs with heights of 200, 300, 400, 500 and 600 mm, respectively. Sodium chloride application of only 100 kg ha−1 lead to 100% death of shrubs smaller than 400 mm high. Although high applications of NaCl led to total death of shrubs 600 mm high, the enormous problem of saline/sodic soil accompanying it must not be disregarded. Molopo successfully killed all shrubs up to a height of 600 mm. As the plant reaches maturity, the root:shoot ratio increases significantly. It was proved that S. plumosum encroachment is not linked to overgrazing. These results confirm the vulnerability of S. plumosum in semiarid areas, following changes in soil characteristics, which can be used in the control of this invasive plant. A combination of methods is recommended for S. plumosum control.

Authors

Snyman, HA

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.745905

This article contributed by:

Original

Influence of mono- and biculture cover cropping systems on soil polysaccharides and aggregate stability in a sandy loam Oakleaf soil in Eastern Cape, South AfricaMupambwa, HA2012

Influence of mono- and biculture cover cropping systems on soil polysaccharides and aggregate stability in a sandy loam Oakleaf soil in Eastern Cape, South Africa

Keywords

aggregate fraction size, mean weight diameter, oat, soil polysaccharides, vetch

Abstract

Mono- and biculture cropping systems are thought to affect aggregate stability by influencing soil polysaccharides but the exact relationship is uncertain. The objective of this study was to determine the effects of cover cropping systems on polysaccharides and aggregate stability in an Oakleaf soil. Two experiments involving a cereal, two legumes and a weedy control, either in mono- or biculture, were done. The crops were oat (Avena sativa L.), vetch (Vicia dasycarpa L.) and lupin (Lupinus angustifolius L.). All cover crops in both cropping systems increased soil polysaccharides. Cover crops in both systems improved aggregation either by increasing macroaggregates and/or lowering the percentage of the 0.25–0.106 mm aggregate fraction size. The mean weight diameter increased under the mono- but not biculture system. The hot-water extractable polysaccharides fraction was actively involved in aggregation in the Oakleaf soil. The correlation between hot-water extractable polysaccharides and the mean weight diameter was negative (r= −0.55) for the monoculture system and positive (r= 0.71) for the biculture system. Microaggregates coalesced even when such increase in size did not trigger a significant increase in the mean weight diameter. Secondly, microaggregates also seemed to serve as building blocks for macroaggregates.

Authors

Mupambwa, HA and Wakindiki, IIC

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.748220

This article contributed by:

Original

Estimation of frost occurrence and duration of frost for a short-grass surfaceSavage, MJ2012

Estimation of frost occurrence and duration of frost for a short-grass surface

Keywords

dielectric constant, grass-surface temperature, ice

Abstract

The estimation of frost duration (FD) was investigated using dielectric, infrared surface temperature and grass temperature subhourly measurements. Near real-time FD data and information displays and alerts were also made available via a web-based system. FD was estimated using a dielectric leaf wetness sensor (LWS) method, for which the sensor voltage was between 274 and 284 mV with a voltage rate of change less than 10 mV h−1 for a 4 min period, and two temperature methods for which infrared thermometer (IRT) and grass temperatures were compared with 0 °C. FD estimation using the LWS method ensured that most of the transitional dry-to-wet and wet-to-dry events were not included in the FD count. Generally, the IRT method yielded the largest estimate of FD, grass temperature method lower and LWS method lowest. Micrometeorological measurements showed consistent air temperature gradients of 2.25 °C m−1 for cloudless nocturnal frosted conditions with few air temperature measurements at 1 m and none above indicating frost occurrence. At the very least, automatic weather station systems should contain a grass thermometer or preferably an IRT for determination of FD with near real-time data and graphics displayed, including timeous alerts of frost occurrence and FD, using the Internet.

Authors

Savage, MJ

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.748938

This article contributed by:

Original

Estimation of leaf wetness duration for a short-grass surfaceSavage, MJ2012

Estimation of leaf wetness duration for a short-grass surface

Keywords

dielectric leaf wetness sensor, grass-surface temperature, nocturnal grass temperature

Abstract

The measurement of leaf wetness duration (LWD) was investigated using subhourly dielectric, infrared surface temperature, dewpoint temperature, grass temperature and relative humidity (RH) measurements. Near real-time LWD data and information displays and alerts were made available timeously via a web-based system. LWD was estimated above a short-grass surface using five methods: dielectric leaf wetness sensors (LWS); a constant RH for which wetness events were registered for RH greater than 87%; RH between 70–87% if RH increased by more than 3% in 30 min; and two dewpoint depression-based methods for which surface-measured temperature, using an infrared thermometer (IRT), and grass temperature were compared with the dewpoint at either 0.1 or 2 m. The RH methods generally overestimated LWD compared to the other methods. There was reasonable agreement between IRT- and grass-temperature methods if rain days were excluded but these methods showed poor agreement with LWS measurements of LWD. Microclimatic and radiative conditions, during nocturnal condensing events, are reported. Automatic weather station data would have more value if grass temperature was included for determination of LWD by comparison of grass temperature with a measured dewpoint, with timeous alerts and web-based display of near real-time LWD data and graphics.

Authors

Savage, MJ

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.750017

This article contributed by:

Original

Evaluating the Streif index against commercial subjective predictions to determine the harvest date of apples in South AfricaLötze, Elmi2012

Evaluating the Streif index against commercial subjective predictions to determine the harvest date of apples in South Africa

Keywords

maturity, prediction, starch breakdown

Abstract

For the local deciduous fruit industry, which mainly exports fruit, determination of the optimum physiological harvest maturity for apples to ensure high fruit quality after long-term storage is still an important goal. This is performed by a subjective determination based on a weekly rate of change of all or some of the ripening parameters such as fruit firmness. In Europe, the Streif index (SI) has been implemented to reduce this subjectivity. The aim of this project was to evaluate this index under local conditions. Historical physiological data for Golden Delicious and Starking apples (Malus domestica Borkh.) from various orchards in the Ceres area were analysed. Significant correlations were obtained between the SI and subjective predictions of the release date for harvesting, after adapting the local starch breakdown values. However, during seasons when the starch conversion rates were very low during the early season, the SI alone may not be sufficient to indicate the release date for harvesting. A multilinear regression equation was also fitted to the maturity data. Likewise the accuracy of this model was influenced by season and variation between individual sites. Both methods can be applied commercially to support the otherwise subjective determination of the harvest dates.

Authors

Lötze, Elmi and Bergh, Oloff

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.691558

This article contributed by:

Original

Carbon and nitrogen mineralisation and inactivation of the Cry1Ab protein in Bt maize (MON810) residues during compostingMuchaonyerwa, P2012

Carbon and nitrogen mineralisation and inactivation of the Cry1Ab protein in Bt maize (MON810) residues during composting

Keywords

chemical composition, compost, Cry1Ab protein, decomposition, lignin

Abstract

Abstract A study was carried out to determine the effects of composting Bt maize residues on carbon (C) and nitrogen (N) contents and activity of the Cry1Ab protein in the compost. Residues (leaf plus stem) of mature Bt maize (DKC 7815B) and its near-isoline (CRN 3505) were composted using 1 m3 wooden boxes. Temperature, C and N transformations, and activity of the Cry1Ab protein were monitored throughout the composting period. Residues of the hybrids used in this study composted similarly as shown by the temperature profiles, pH, C and N dynamics. The C:N ratios decreased from 33 and 23 for the Bt maize and near-isoline, respectively, to 15. Composting reduced the activity of the Bt protein in the residues, with a half-life of 3.3 d, to 22%, 7% and 3% of the initial level (90.5 ng g–1) in 7, 14 and 35 d, respectively, and approached undetectable levels after 63 d. The findings of this study suggest that Bt maize composts in the same way as conventional maize. The composting rapidly reduced the much higher C:N ratio of Bt maize and in the process eliminated the active Bt proteins in the residues, thus rendering them much safer for soil application.

Authors

Muchaonyerwa, P, Daudu, CK and Mnkeni, PNS

Year Published

2012

Publication

South African Journal of Plant and Soil

Locations
DOI

10.1080/02571862.2012.700076

This article contributed by:

Original

Recent Articles

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by Turner, David P

The paper discusses revised principles, perspectives and structure for soil classification of natural soils in South Africa. An expanded ‘sphere of pedological interest’ is proposed through the formal recognition of a wider range of subsurface soil materials. The concept of soil groups has been recognised and is further developed as a formal classification category. In addition, a subgroup cate...

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Phytochemical Content, Antioxidant Capacity and Physicochemical Properties of Pomegranate Grown in Different Microclimates in South Africa

by Mditshwa, Asanda, Fawole, Olaniyi A, Al-Said, Fahad, Al-Yahyai, Rashid and Opara, Umezuruike L

We investigated the antioxidant and physicochemical properties of pomegranate (Punica granatum cv. Bhagwa) fruit grown in three microclimates in South Africa. The physicochemical properties of fruit peel and arils differed among the growing locations, including weight and redness color of both peel and arils. Contents of vitamin C, anthocyanin and total phenolics were 0.67–1.41 mg ml−1, 0.07–0....

published 2013 in South African Journal of Plant and Soil


Estimation of Thrips (fulmekiola Serrata Kobus) Density in Sugarcane Using Leaf-Level Hyperspectral Data

by Abdel-Rahman, Elfatih M, Way, Mike, Ahmed, Fethi, Ismail, Riyad and Adam, Elhadi

The aim of this study was to investigate the potential use of leaf-level hyperspectral data to predict the density of sugarcane thrips Fulmekiola serrata (Kobus). A hand-held spectroradiometer was used to make the spectral measurements on spindle leaves of 4- to 5-month-old plants of sugarcane cv. N19 growing in commercial fields near Umfolozi, South Africa. A random forest algorithm followed b...

published 2013 in South African Journal of Plant and Soil

A Revised Perspective on Principles of Soil Classification in South Africa

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Limited significance has been given to the formal recognition of certain subsoil materials in the South African Soil Classification System. Three principles in the current classification system are discussed using variants of soil profiles associated with the Avalon soil form. The retention of the arbitrary depth criterion is questioned in favour of the recognition of an enlarged ‘sphere of ped...

published 2013 in South African Journal of Plant and Soil