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Ontogeny of Themeda triandra tillers in the false thornveld of the eastern cape
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: J.E. Danckwerts --- Department of Agriculture (Eastern Cape Region), A.J. Aucamp --- Department of Agriculture (Eastern Cape Region), L.P. Du Toit --- Department of Agriculture (Eastern Cape Region),Marked populations of Themeda triandra tillers were sequentially sampled at fortnightly intervals under normal conditions and without moisture stress respectively, covering a period from tiller initiation through to senescence after flowering. Parameters recorded were height of shoot apex, tiller mass,... -
Die invloed van drie tussenrybewerkingsmetodes op opbrengs en chemiese samestelling van droëlandlusern op die oos‐transvaalse hoëveld.
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: L.T. Botha --- , M. de Villiers --- , W.T. Oosthuizen --- ,Drie tussenrybewerkingsmetodes, skeurploeg (40 — 50 cm diep) skoffel (5 — H) cm diep) en kontrole (geen bewerking) is gedurende die 1982/83 en 1983/84 groeiseisoene in ‘n bestaande lusernstand uitgevoer. Hierdie lusern was in 0,9 m rye gevestig. Tye van... -
Evapotranspirasie en waterverbruiksdoeltreffendheid van verskillende grasspesies in die sentrale Oranje‐Vrystaat
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: H.A. Snyman --- , Republiek van Suid‐AfrikaEvapotranspiration and water use efficiency of different grass species in the central Orange Free State. Evapotranspiration (Et) and water use efficiency (WUE) were determined for each of seven grass species during the 1986/87 and 1987/88 seasons. The highest and lowest... -
Some effects of termitaria on veld in the eastern Cape
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: T.D. Steinke --- Department of Botany, Republic of South Africa L.O. Nel --- Department of Agriculture (Eastern Cape Region), Republic of South AfricaA survey was conducted to determine some effects of termite mounds on the veld. Termitaria were found to occupy approximately 0,4% of the area of the paddock under investigation. Growth of grasses immediately surrounding intact termitaria increased as shown by... -
Quantitative description of woody plant communities: Part I. An approach
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.N. Smit --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South AfricaVarious descriptive units for woody plant communities are proposed. These are the Evapotranspiration Tree Equivalent (ETTE), Browse Tree Equivalent (BTE) and Canopied Subhabitat Index (CSI), which describe the status of a woody community in terms of potential moisture use, value... -
Die rol van sekere omgewingsfaktore by alachloraktiwiteit
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: C.F. Reinhardt --- Departement Plantproduksie, P.C. Nel --- Departement Plantproduksie,Biotoetse met graansorghum (Sorghum bicolor L.) is in potte in glashuise en groeikabinette uitgevoer. Geselekteerde grond- eienskappe is gekorreleer met alachloraktiwiteit. Organiese materiaalinhoud (% C) was die beste gekorreleerd met die aktiwiteit van alachlor en pH die swakste. Die r-waardes... -
Effect of moisture supply on CAM in Opuntia aurantiaca (jointed cactus)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: B.H. Whiting --- Department of Botany, E.E. Campbell --- Department of Botany,The patterns of gas exchange exhibited by Opuntia aurantiaca under controlled conditions (photoperiod 12 h; day/night temperature regime 30/15°C) were investigated for plants subjected to various levels of moisture stress. Unstressed plants exhibited a typical full-CAM pattern of gas exchange... -
Changes in percentage moisture loss of excised leaves of seven field-grown grain sorghum genotypes
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W.G. Wenzel --- , Republic of South Africa W.J. van den Berg --- , Republic of South AfricaThe objectives of these experiments were to study the seasonal and diurnal changes in percentage moisture loss (PML) and correlated characteristics of excised leaves. Seven grain sorghum genotypes were planted in a randomized block design and their PML and the... -
Effect of pre- and post-harvest water stress on the potential for fruit quality defects in avocado (Persea americana Mill.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J.P. Bower --- , Republic of South Africa J. G.M. Cutting --- , Republic of South Africa B.N. Wolstenholme --- , Republic of South AfricaPhysiological and pathological disorders of avocado fruit are a limitation to export sales. The influence of pre-harvest water stress on post-harvest quality was studied using a long-term irrigation trial, i.e., re-wetting in the root zone when soil water tensions reached... -
Effects of sample drying temperature on indices of available nitrogen in soils
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.H. Wiltshire --- Department of Soil Science, Republic of South Africa C.C. du Preez --- Department of Soil Science, Republic of South AfricaDuring a field trial investigation into the long-term effects of conservation practices on the nitrogen fertility of a soil cropped annually to wheat, it was observed that sample preparation had an effect on some indices of available nitrogen. The trial... -
A comparison of three methods of soil water content determination
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K.M. Little --- , Republic of South Africa B. Metelerkamp --- , New Zealand C.W. Smith --- , Republic of South AfricaIn forestry the need to manage plantations on a sustainable site-specific basis requires the understanding and management of any growth limiting factors. Soil water regime is a factor considered to be of prime importance with respect to explaining differences in... -
Die invloed van die voginhoud op die dopbaarheid van sonneblomsaad
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republiek van Suid-Afrika H.L. Loubser --- , Republiek van Suid-Afrika P.S. Hammes --- Departement Plantproduksie en Grondkunde, Republiek van Suid AfrikaDie voginhoud van sonneblomsaad (Helianthus annuns L.) wat vir persing gebruik word, wissel tussen 5.5% (ongeveer die laagste inhoud waartoe saad natuurlik droog) en 10% (die hoogste toelaatbare inhoud vir berging). Die doel van die ondersoek was om vas te... -
Effect of moisture stress on sorghum yield and its components
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: W.G. Wenzel --- , Republic of South AfricaA sample of 48 sorghum varieties and inbred lines were planted in randomized block designs in two trials, one of which was irrigated. The effect of moisture stress on grain yield, tillering, seeds per ear, ear mass, seeds per plot,... -
Using different sample holders in determining protein and moisture content in whole wheat flour by means of Fourier transform near infrared (FT-NIR) spectroscopy
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: L. van Zyl --- Department of Food Science, Republic of South Africa M. Manley --- Department of Food Science, Republic of South Africa B.G. Osborne --- , AustraliaFourier transform near infrared (FT-NIR) spectroscopy was used to record the spectra of 92 whole wheat flour samples presented in three different sample holders. The conventional sample cup with a sapphire-glass base (provided with the spectrophotometer), borosilicate-glass vials and soda-glass... -
Stimulation and suppression of mineralisation and nitrification in incubated soil
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K. Agrella --- Department of Plant Production and Soil Science, South Africa P. Boeckx --- Department of Applied Analytical and Physical Chemistry, Belgium A.S. Claassens --- Department of Plant Production and Soil Science, South Africa O. Van Cleemput --- Department of Applied Analytical and Physical Chemistry, BelgiumPriming, induced through the addition of oxidisable organic matter, releases or immobilises nitrogen and other nutrients in the soil. Moisture plays a very important role in priming as it stimulates microbial activity after a dry soil is wetted, especially with... -
Germination strategies of Strandveld Succulent Karoo plant species for revegetation purposes: III Effect of relative humidity and storage site on seed viability
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.J. de Villiers --- Department of Botany, Republic of South Africa M.W. van Rooyen --- Department of Botany, Republic of South Africa G.K. Theron --- Department of Botany, Republic of South AfricaChanges in seed viability owing to fluctuations in environmental conditions (temperature and relative humidity) are crucial factors to consider during post-mining revegetation efforts in the Strandveld Succulent Karoo. The effect of relative humidity and storage site on seed viability was... -
Effect of temperature, soil moisture content and type of cutting on establishment of sweet potato cuttings
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: T. Belehu --- Department of Plant Production and Soil Science, Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaEffective rooting is essential for successful crop establishment from cuttings. The objective of this study was to determine the effect of temperature and soil water content on the root and shoot growth during the early establishment of sweet potato cuttings... -
Significance of kernel moisture content in determination of Hagberg Falling Number in wheat
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: M. Craven --- , South Africa A. Barnard --- , South Africa M.T. Labuschagne --- , South AfricaThe effect of early termination of kernel filling (early harvest) on the Hagberg Falling Number (HFN) was investigated over a four-year period. Selected South African wheat cultivars were harvested at different stages of kernel development, determined by kernel moisture content... -
Morphological characters and ascorbic acid content of an elite genotype of Corchorus olitorius: the influence of moisture stress
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: AnofiOT Ashafa --- Department of Plant Sciences, South Africa AbidemiA Abass --- Department of Botany, Nigeria Titilola Osinaike --- Department of Botany, Nigeria FrancisB Lewu --- Agriculture Department, South AfricaMoisture stress can be deleterious to physicochemical properties of crop species to a varying degree. The influence of moisture stress on the ascorbic acid content in the leaf and morphological characters of an elite genotype of Corchorus olitorius were tested... -
Effect of Balanites glabra canopy cover on grass production, organic matter and soil moisture in a southern Kenyan rangeland
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: VO Wasonga RK Ngugi DM Nyariki G Kironchi TJ NjokaA study was undertaken in Kenya's southern savanna rangelands to determine the seasonal effect of Balanites glabra canopy cover on aboveground grass biomass, grass species composition, soil organic matter and soil moisture content. The study was conducted during the period... -
Secondary succession in the Mopani veld of the Limpopo Valley, South Africa
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: JJ Jordaan DCJ Wessels CS Dannhauser GT RootmanThe long-term establishment sequences of the herbaceous and woody component of the Mopani veld of the Limpopo Valley were studied and documented. Based on vegetation surveys conducted at three enclosed sites at the Messina Experimental Farm during the period 1964... -
Influence of moisture stress on growth, dry matter yield and allocation, water use and water-use efficiency of four Indigofera species
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: A Hassen NFG Rethman Z Apostolides WA van NiekerkThe effects of moisture stress were evaluated in four Indigofera species (I. amorphoides, I. arrecta, I. coerulea and I. vicioides) using a pot experiment under glasshouse conditions. The aim was to examine the influence of moisture-deficit stress on physiological attributes... -
Factors Affecting the Timing of Grassland Regrowth after Fire in the Montane Grasslands of Natal
Item type: Journal Article • Journal: South African Forestry Journal • Authors: C.S. Everson --- , South Africa TheresaM. Everson --- , South AfricaRecent research has indicated that burning Highland Sourveld once growth has been initiated increases grass tiller mortality. Present burning prescriptions could therefore be improved by an insight into the factors controlling the initiation of grass growth in spring. It was... -
Variation in Wood Properties of Eucalyptus nitens in a Provenance Trial on the Eastern Transvaal Highveld in South Africa
Item type: Journal Article • Journal: South African Forestry Journal • Authors: R.C. Purnell --- D.R. de Wet Forestry Research Centre,Eucalyptus nitens is one of the four important cold-tolerant eucalypts grown for mining timber and pulpwood on the eastern Transvaal highveld in South Africa. In 1983 an active genetic improvement programme was initiated to improve growth rate, stem form and... -
Curing Rates in the Grass Sward of the Highland Sourveld in the Natal Drakensberg
Item type: Journal Article • Journal: South African Forestry Journal • Authors: TheresaM. Everson --- , C.S. Everson --- , H.M. Dicks --- , A.G. Poulter --- ,Data on the curing rates of one, two and three-year-old grassland are presented. Curing is initiated at the end of April and progresses rapidly up to the middle of May. By June the grasses are 95 % cured, increasing the... -
Effect of rainfall and under-canopy vegetation on the ability to debark Eucalyptus grandis x E. camaldulensis when felled in Zululand, South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Gert J. van den Berg --- , Republic of South Africa Keith M. Little --- , Republic of South AfricaThe combined effects of seasonal variation in rainfall and the presence or absence of under-canopy vegetation on soil moisture content may have a negative or positive impact on the ability to debark eucalypts. A study was initiated to investigate these... -
Fermentative characteristics of Digitaria eriantha subsp. eriantha silage harvested at different stages of maturity
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: WA van Niekerk Abubeker Hassen FM BechazAn experiment was conducted to investigate the influence of stage of growth at harvest on fermentative characteristics of Digitaria eriantha subsp. eriantha silage. The treatment included three different growth stages (early vegetative, boot stage and full-bloom stage). The materials were... -
Influence of molasses additive and moisture level at ensiling on fermentative characteristics of Panicum maximum
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: WA van Niekerk A Hassen FM BechazSilages made from directly cut or wilted Panicum maximum treated with or without molasses, were evaluated to determine fermentative characteristics. The grass was harvested at the boot stage of growth and the material of each treatment was ensiled in separate... -
Effect of temperature on cone bursting, seed extraction and germination in five provenances of Pinus roxburghii from Garhwal Himalaya in India
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: SK Ghildiyal CM Sharma S GairolaPinus roxburghii (chir pine or long-needle pine) is considered to be a fire-hardy species. In this study the effect of a wide range of elevated temperatures (from 40 °C to 150 °C) on cone bursting and subsequent seed germination was... -
Sorghum production systems and constraints, and coping strategies under drought-prone agro-ecologies of Ethiopia
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Beyene A Amelework --- African Centre for Crop Improvement, South Africa Hussein A Shimelis --- African Centre for Crop Improvement, South Africa Pangirayi Tongoona --- West African Centre for Crop Improvement, College of Basic and Applied Sciences, Ghana Fentahun Mengistu --- Ethiopian Institute of Agricultural Research, Ethiopia Mark D Laing --- African Centre for Crop Improvement, South Africa Dawit Getnet Ayele --- School of Mathematics, Statistics and Computer Science, South AfricaSorghum is one of the most important cereal crops worldwide after wheat, rice, maize and barley. Examining the present socio-economic conditions of sorghum-producing farmers in different agro-ecologies in Ethiopia is of importance for the design of improvement strategies. The objectives... -
The effect of conditioning and natural aeration methods on rate of moisture loss and crude protein content of Lablab purpureus herbage during hay-making
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Godfrey Manyawu --- International Livestock Research Institute, Zimbabwe Lovemore C Gwiriri --- Centre for Agroecology, UK Irenie Chakoma --- International Livestock Research Institute, Zimbabwe Siboniso Moyo --- International Livestock Research Institute, Ethiopia Sikhalazo Dube --- International Livestock Research Institute, ZimbabweThe objective of this on-farm study was to develop an effective and labour-extensive method to cure forage Lablab purpureus ‘Highworth’ for resource-constrained smallholder farmers in the Goromonzi district, Zimbabwe in 2014. In a completely randomised factorial design, the drying rate... -
Equilibrium sorption isotherms of Moringa oleifera leaves at different temperatures
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Sunday Samuel Sobowale --- Department of Food Technology, Nigeria Moruf Olanrewaju Oke --- Department of Food Science and Engineering, Nigeria Lukumon Ayinde Odunmbaku --- Department of Food Technology, Nigeria Oluwafemi Ayodeji Adebo --- Department of Biotechnology and Food Technology, Faculty of Science, South AfricaAdsorption and desorption isotherms for Moringa oleifera leaves were investigated using concentrated H2SO4 solutions to vary the micro-climate over different temperatures (27, 32, 37°C) and water activity (aw) (0.1–0.8). Plots of equilibrium moisture content (EMC) against aw were used to... -
Development of a charcoal-fuelled dryer for the production of organic fertilizer from hog waste
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: B.O. Akinnuli --- Department of Mechanical Engineering, Nigeria O.P. Bodunde --- Department of Mechanical Engineering, NigeriaThe negligence of livestock farmers regarding waste disposal and inadequate waste control facilities are becoming a serious health and environmental hazard. In this study, a charcoal-fuelled dryer was developed to eliminate the moisture content in hog waste for easy conversion... -
The impact of log surface damage caused by harvester Eucalyptus debarking on pulp value recovery
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Jaco-Pierre van der Merwe --- Department of Forest and Wood Science, South Africa Reino Pulkki --- Department of Forest and Wood Science, South Africa Pierre Ackerman --- Department of Forest and Wood Science, South Africa Dirk Längin --- Mondi Ltd, South AfricaMechanised harvesting operations are growing in popularity in South Africa, as motor-manual and manual harvesting operations pose significant health and safety risks to workers. Potential damage inflicted by single-grip harvester feed rollers and delimbing knives on the log surface during... -
Population fluctuations of Cerithidea decollata (Gastropoda: Potamididae) in mangrove habitats of the St Lucia Estuary, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: JL Raw --- , South Africa GM Rishworth --- , South Africa R Perissinotto --- , South Africa JB Adams --- , South AfricaMangrove macrobenthos species are used as ecological indicators as they are sensitive to changes in sediment properties. In this study, the population density of the common mangrove whelk Cerithidea decollata was assessed during different environmental conditions in the St Lucia... -
Drip irrigation systems controlled by soil moisture sensors and a soil water balance model for cassava grown in soils of two different textures
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Xintai Xie --- , Thailand Thitiporn Machikowa --- , Thailand Sodchol Wonprasaid --- , ThailandCassava (Manihot esculenta Crantz) yield could be improved by drip irrigation if irrigation scheduling is correctly organized. Soil moisture content is an important factor for controlling irrigation. It can be directly monitored by soil moisture sensors or predicted by soil... -
Earthworm diversity and density as affected by soil and climatic factors in Raymond Mhlaba municipality, Eastern Cape province, South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Sixolise Mcinga --- , South Africa Alen Manyevere --- , South Africa P Mnkeni --- , TanzaniaEarthworms play a key role in improving soil health, and their diversity and density are mainly affected by soil and climatic factors. This study determined the effects of rainfall, temperature and selected soil properties on the diversity and density of... -
An IoT-based soil moisture monitor
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Opeyemi A. Osanaiye --- Nile University of Nigeria, Nigeria Thomas Mannan --- Federal University of Technology, Nigeria Folayo Aina --- University of Central Lancashire, United KingdomOver the years, monitoring soil moisture levels of farmlands has been performed manually. This is often time-consuming and inefficient, necessitating a solution that is efficient in controlling and monitoring soil moisture conditions. This work therefore proposes an Internet of Things... -
The influence of grass competition and soil moisture on the growth and phenology of Karoo shrubs in the Eastern Upper Karoo
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Lisa Hebbelmann --- , South Africa Timothy G O’Connor --- , South Africa Justin CO du Toit --- Grootfontein Agricultural Development Institute, South AfricaRainfall in the Nama-Karoo is sporadic and a plant’s ability to access and utilise available soil moisture will determine its ability to persist in the system and to successfully recruit. When summer rainfall in the Eastern Karoo increases, grassiness increases... -
Refinement of a site classification system for South African plantation forestry using regionally downscaled climate model input
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Steven Dovey --- Scion (NZ Forest Research Institute Ltd), New Zealand Jacob Crous --- Sappi Shaw Research Centre, South Africa Yolandi Ernst --- Global Change Institute, University of the Witwatersrand, South AfricaDeemed a climate change hotspot, southern Africa is already experiencing increasing average temperatures associated with extreme weather events, such as drought and flooding. Climate change has already induced many weather and climate extremes in South Africa, and these are likely...