Pub Date : 2021-10-20DOI: 10.1080/02571862.2021.1966108
J. Fourie, C. Howell, M. Booyse, Kim M Adams
Five treatments were applied in a newly established orchard on a loamy sand near Vyeboom, South Africa. Treatment 1 (T1): chemical control in the tree row from bud break to harvest, with dwarf fescue (Festuca arundinaceae Schreb.) slashed regularly in the work row. Treatment 2 (T2): ‘Saia’ oats (Avena strigosa Schreb. ‘Saia’) in the work row, with full surface chemical control (CC) applied early October and the beginning of December. Treatment 3 (T3): pink serradella (Ornithopus sativus Brot. ‘Emena’) in the work row and a subterranean clover (Trifolium subterraneum L. ‘Campeda’) in the tree row and CC. Treatment 4 (T4): a mixture of ‘Saia’ oats and pink serradella in the work row and CC. Treatment 5 (T5): a mixture of canola (Brassica napus L. ‘AVGarnet’) and ‘Caliente 199’ brown-mustard (Brassica juncea (L.) Czern. ‘Caliente 199’) in the work row and CC. T2 was the best performing treatment for the control of the winter and early summer growing weeds, while T1 controlled the late summer growing weeds the most effectively. T4 caused the highest increase in soil organic carbon, while T3 achieved the highest release of total inorganic N during the growing season (November to January).
{"title":"Cover crop performance in an apple orchard and its effect on the macro-elements and carbon levels in a loamy sand","authors":"J. Fourie, C. Howell, M. Booyse, Kim M Adams","doi":"10.1080/02571862.2021.1966108","DOIUrl":"https://doi.org/10.1080/02571862.2021.1966108","url":null,"abstract":"Five treatments were applied in a newly established orchard on a loamy sand near Vyeboom, South Africa. Treatment 1 (T1): chemical control in the tree row from bud break to harvest, with dwarf fescue (Festuca arundinaceae Schreb.) slashed regularly in the work row. Treatment 2 (T2): ‘Saia’ oats (Avena strigosa Schreb. ‘Saia’) in the work row, with full surface chemical control (CC) applied early October and the beginning of December. Treatment 3 (T3): pink serradella (Ornithopus sativus Brot. ‘Emena’) in the work row and a subterranean clover (Trifolium subterraneum L. ‘Campeda’) in the tree row and CC. Treatment 4 (T4): a mixture of ‘Saia’ oats and pink serradella in the work row and CC. Treatment 5 (T5): a mixture of canola (Brassica napus L. ‘AVGarnet’) and ‘Caliente 199’ brown-mustard (Brassica juncea (L.) Czern. ‘Caliente 199’) in the work row and CC. T2 was the best performing treatment for the control of the winter and early summer growing weeds, while T1 controlled the late summer growing weeds the most effectively. T4 caused the highest increase in soil organic carbon, while T3 achieved the highest release of total inorganic N during the growing season (November to January).","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43241877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-20DOI: 10.1080/02571862.2021.1938261
I. Gura, P. Mnkeni, C. du Preez, J. Barnard
Soil organic carbon (SOC) is a major indicator of soil quality and/or health but its slow short-term response to management changes has prompted the search for more sensitive indicators for monitoring short-term changes in soil organic matter (SOM). This study aimed to investigate the short-term effects of crop rotation systems and residue management practices under no tillage on selected soil carbon fractions of a Haplic Cambisol, using plots from a conservation agriculture (CA) field trial (split plot design replicated in three blocks). The main plots were comprised of the crop rotation systems: maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). Residue management practices that included residue removal (R−) and residue retention (R+) were allocated to the sub-plots. The carbon fractions measured were SOC, microbial biomass carbon (MBC), mineralisable carbon (Cmin) and particulate organic matter carbon fractions (POM-C). Crop rotation systems significantly (p < 0.05) influenced Cmin and POM-C fractions whereas residue management practices significantly (p < 0.05) affected all the carbon fractions. Crop residue retention as opposed to its removal enhanced all the carbon pools. The POM-C and Cmin fractions were more sensitive to short-term CA management interventions than SOC and MBC, therefore they can be used for monitoring SOM changes and microbial activities.
{"title":"Response of soil carbon fractions in a Haplic Cambisol to crop rotation systems and residue management practices under no tillage in the Eastern Cape, South Africa","authors":"I. Gura, P. Mnkeni, C. du Preez, J. Barnard","doi":"10.1080/02571862.2021.1938261","DOIUrl":"https://doi.org/10.1080/02571862.2021.1938261","url":null,"abstract":"Soil organic carbon (SOC) is a major indicator of soil quality and/or health but its slow short-term response to management changes has prompted the search for more sensitive indicators for monitoring short-term changes in soil organic matter (SOM). This study aimed to investigate the short-term effects of crop rotation systems and residue management practices under no tillage on selected soil carbon fractions of a Haplic Cambisol, using plots from a conservation agriculture (CA) field trial (split plot design replicated in three blocks). The main plots were comprised of the crop rotation systems: maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). Residue management practices that included residue removal (R−) and residue retention (R+) were allocated to the sub-plots. The carbon fractions measured were SOC, microbial biomass carbon (MBC), mineralisable carbon (Cmin) and particulate organic matter carbon fractions (POM-C). Crop rotation systems significantly (p < 0.05) influenced Cmin and POM-C fractions whereas residue management practices significantly (p < 0.05) affected all the carbon fractions. Crop residue retention as opposed to its removal enhanced all the carbon pools. The POM-C and Cmin fractions were more sensitive to short-term CA management interventions than SOC and MBC, therefore they can be used for monitoring SOM changes and microbial activities.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42794127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1907465
Mohammed A Elgorashi Bakhite, N. Sithole, L. S. Magwaza, A. Odindo, J. Derera
Plant breeders have focused on reducing phytic acid in maize seeds to improve grain nutritional quality. However, this could have negative effects on seed quality. The objective of this study was to compare seed performance of low and high phytic acid (LPA and HPA) synthetic populations of tropical origin with two hybrid varieties (SC701 and LS8520). Four replicates of 20 seeds per variety were germinated in a randomized complete block design for a standard germination test. Seeds were also subjected to an accelerated ageing (AA) test. The results of the final seed germination percentage were as follows: HPA (98.0%) > SC701 (93.0%) > LPA (90.0%) > LS8520 (85.0%). However, statistically, HPA seeds were similar (p > 0.05) to SC701 seeds and LPA seeds were similar (p > 0.05) to SC701 seeds. The mean germination time (MGT) was similar for all varieties, however, the germination velocity index (GVI) was highest (p < 0.05) for SC701 and similar (p > 0.05) in LPA and HPA. Both SC701 and HPA showed higher percentages germination when they were exposed to the AA test. It was concluded that the LPA population had similar seed quality parameters to high performing varieties.
{"title":"Comparison of seed germination and vigour in low and high phytic acid maize synthetic populations and commercially available hybrids","authors":"Mohammed A Elgorashi Bakhite, N. Sithole, L. S. Magwaza, A. Odindo, J. Derera","doi":"10.1080/02571862.2021.1907465","DOIUrl":"https://doi.org/10.1080/02571862.2021.1907465","url":null,"abstract":"Plant breeders have focused on reducing phytic acid in maize seeds to improve grain nutritional quality. However, this could have negative effects on seed quality. The objective of this study was to compare seed performance of low and high phytic acid (LPA and HPA) synthetic populations of tropical origin with two hybrid varieties (SC701 and LS8520). Four replicates of 20 seeds per variety were germinated in a randomized complete block design for a standard germination test. Seeds were also subjected to an accelerated ageing (AA) test. The results of the final seed germination percentage were as follows: HPA (98.0%) > SC701 (93.0%) > LPA (90.0%) > LS8520 (85.0%). However, statistically, HPA seeds were similar (p > 0.05) to SC701 seeds and LPA seeds were similar (p > 0.05) to SC701 seeds. The mean germination time (MGT) was similar for all varieties, however, the germination velocity index (GVI) was highest (p < 0.05) for SC701 and similar (p > 0.05) in LPA and HPA. Both SC701 and HPA showed higher percentages germination when they were exposed to the AA test. It was concluded that the LPA population had similar seed quality parameters to high performing varieties.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48119687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1909155
GJ Malan, WP De Clercq, Andrei Rozanov, C. Clarke, H. Helness, S. Damman, N. Elema, J. Atkinson
Recent climate instability necessitates a fresh approach to water cycle services in the Hessequa municipal region. Attention is drawn to impacts on water storage in this region, and an assessment of the current status is necessary. Land-use change and soil properties are focal points of a runoff assessment. Defining Land Type soils information is necessary to support agricultural needs, concentrating on depth-limiting materials, mechanical limitations and texture. It is evident in the area under study that mountainous regions are not well-described. With most dams located in mountain regions and the land increasingly being used for agroforestry, the demand for better supporting information has increased. Furthermore, the available Land Type polygons for the region are too coarse for the catchment, which is primarily undulated. Enhanced Land Type mapping resolution may be defined through terrain morphological segmentation. The process indicates that the terrain prediction capability is acceptable, with 62% and 74% within 4 and 15 m search windows, respectively. This information has provided a broader platform to enhance our ability to deal with the impacts of climate and land-use change in the Korentepoort mountain catchment.
{"title":"Increased resolution of soils information through morphon segmentation of the Korentepoort mountain catchment","authors":"GJ Malan, WP De Clercq, Andrei Rozanov, C. Clarke, H. Helness, S. Damman, N. Elema, J. Atkinson","doi":"10.1080/02571862.2021.1909155","DOIUrl":"https://doi.org/10.1080/02571862.2021.1909155","url":null,"abstract":"Recent climate instability necessitates a fresh approach to water cycle services in the Hessequa municipal region. Attention is drawn to impacts on water storage in this region, and an assessment of the current status is necessary. Land-use change and soil properties are focal points of a runoff assessment. Defining Land Type soils information is necessary to support agricultural needs, concentrating on depth-limiting materials, mechanical limitations and texture. It is evident in the area under study that mountainous regions are not well-described. With most dams located in mountain regions and the land increasingly being used for agroforestry, the demand for better supporting information has increased. Furthermore, the available Land Type polygons for the region are too coarse for the catchment, which is primarily undulated. Enhanced Land Type mapping resolution may be defined through terrain morphological segmentation. The process indicates that the terrain prediction capability is acceptable, with 62% and 74% within 4 and 15 m search windows, respectively. This information has provided a broader platform to enhance our ability to deal with the impacts of climate and land-use change in the Korentepoort mountain catchment.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44103076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1925760
Esnart Nyirenda Yohane, H. Shimelis, M. Laing, A. Shayanowako, I. Mathew, Justus M Chintu
Pigeonpea Cajanus cajan (L.) Millsp. is the most important legume cash crop grown in Malawi. However, productivity is low due to biotic and abiotic stresses and socioeconomic constraints. The objectives of this study were to determine farmers’ perceived constraints to pigeonpea production and to identify the varieties and traits preferred by farmers in Malawi. A participatory rural appraisal was conducted in four major pigeonpea growing districts (viz. Chiradzulu, Mulanje, Thyolo and Zomba) in Malawi. Data were collected using a semi-structured questionnaire, focus group discussions and transect walks. ‘Mthawajuni’ was the most preferred variety grown by 45% of the respondents, due to its palatability and resistance to pod borers. The farmers identified insects, diseases, late-maturing varieties and small land holdings as the most important constraints to pigeonpea production in Malawi. Short cooking time, palatability, high yield, early maturity, long shelf-life, pest and disease resistance, large seeds and cream colour were the most preferred traits of the pigeonpea. The constraints experienced by farmers and their preferences for the identified traits should be considered as selection criteria during the breeding of new pigeonpea varieties in Malawi.
{"title":"Pigeonpea production constraints and farmers’ trait preferences in Malawi: implications for variety design","authors":"Esnart Nyirenda Yohane, H. Shimelis, M. Laing, A. Shayanowako, I. Mathew, Justus M Chintu","doi":"10.1080/02571862.2021.1925760","DOIUrl":"https://doi.org/10.1080/02571862.2021.1925760","url":null,"abstract":"Pigeonpea Cajanus cajan (L.) Millsp. is the most important legume cash crop grown in Malawi. However, productivity is low due to biotic and abiotic stresses and socioeconomic constraints. The objectives of this study were to determine farmers’ perceived constraints to pigeonpea production and to identify the varieties and traits preferred by farmers in Malawi. A participatory rural appraisal was conducted in four major pigeonpea growing districts (viz. Chiradzulu, Mulanje, Thyolo and Zomba) in Malawi. Data were collected using a semi-structured questionnaire, focus group discussions and transect walks. ‘Mthawajuni’ was the most preferred variety grown by 45% of the respondents, due to its palatability and resistance to pod borers. The farmers identified insects, diseases, late-maturing varieties and small land holdings as the most important constraints to pigeonpea production in Malawi. Short cooking time, palatability, high yield, early maturity, long shelf-life, pest and disease resistance, large seeds and cream colour were the most preferred traits of the pigeonpea. The constraints experienced by farmers and their preferences for the identified traits should be considered as selection criteria during the breeding of new pigeonpea varieties in Malawi.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48939716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1930209
F. Müller
This study evaluated the impacts of pH on the germination and early seedling growth of Calobota sericea and Lessertia frutescens subsp. frutescens, two perennial legume species found in the semi-arid rangelands of South Africa. The results of this study revealed that L. frutescens had higher seed germination under more acidic conditions, while C. sericea had higher seed germination under alkaline conditions. Similarly, L. frutescens seedlings were found to be larger under more acidic conditions, while C. sericea seedlings were larger under more alkaline conditions. Both species were able to germinate under all of the pH treatments, suggesting that they are adapted to a wide range of pH conditions, at least at the germination and early seedling growth stage.
{"title":"Contrasting effects of soil pH on seed germination and early seedling growth of Calobota sericea and Lessertia frutescens subs. frutescens","authors":"F. Müller","doi":"10.1080/02571862.2021.1930209","DOIUrl":"https://doi.org/10.1080/02571862.2021.1930209","url":null,"abstract":"This study evaluated the impacts of pH on the germination and early seedling growth of Calobota sericea and Lessertia frutescens subsp. frutescens, two perennial legume species found in the semi-arid rangelands of South Africa. The results of this study revealed that L. frutescens had higher seed germination under more acidic conditions, while C. sericea had higher seed germination under alkaline conditions. Similarly, L. frutescens seedlings were found to be larger under more acidic conditions, while C. sericea seedlings were larger under more alkaline conditions. Both species were able to germinate under all of the pH treatments, suggesting that they are adapted to a wide range of pH conditions, at least at the germination and early seedling growth stage.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46304643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1913767
Tebogo J Lebea, N. Jovanović, M. Kena, K. Ayisi, Wisani G Mushadu
Intensification of low-tech agricultural production is required in the Greater Giyani Municipality (Limpopo province, South Africa) to respond to changing climatic conditions, water scarcity and increased food demand of the local market. Two years of field experiments were conducted on two typical small-scale farms under real-world conditions. The objective was to test the response of locally available tomato (Lycopersicon esculentum Mill.) cultivars (Rodade, STAR 9006, Commander, HTX 14 and MFH) to two different irrigation strategies (full irrigation FI and deficit irrigation DI). While results showed high tomato yield variability (ranging between 9.2 t ha−1 and 59.7 t ha−1) depending on the farms, environmental conditions (heatwaves, diseases) and irrigation management, STAR 9006 appeared to be the best performing cultivar and HTX 14 the worst. Seasonal evapotranspiration under FI was between 400 and 620 mm depending on the length of the season and harvesting time. Crop water productivity was generally higher for DI than FI treatments. Deficit irrigation appeared to be feasible to reduce water use for some cultivars (eg cv. STAR 9006), however, an economic analysis should be conducted at specific sites/farms to determine the impacts of DI on farmers’ income as some yield losses can be expected during drought years.
大吉亚尼市(南非林波波省)需要加强低技术农业生产，以应对不断变化的气候条件、水资源短缺和当地市场粮食需求增加。在现实条件下，在两个典型的小规模农场进行了为期两年的田间试验。目的是测试当地番茄(Lycopersicon esculentum Mill.)品种(Rodade、STAR 9006、Commander、HTX 14和MFH)对两种不同灌溉策略(完全灌溉FI和亏缺灌溉DI)的反应。结果表明，根据不同的种植方式、环境条件(热浪、病害)和灌溉管理，番茄产量变异较大(在9.2 ~ 59.7 t ha - 1之间)，STAR 9006表现最好，htx14表现最差。FI下的季节蒸散量在400 ~ 620 mm之间，取决于季节长度和收获时间。DI处理的作物水分生产力普遍高于FI处理。亏缺灌溉似乎是可行的，以减少一些品种的用水量(如cv。STAR 9006)，但是，应在特定地点/农场进行经济分析，以确定DI对农民收入的影响，因为在干旱年份可能会出现一些产量损失。
{"title":"Response of tomato cultivars to irrigation management strategies employed by emerging farmers in the Greater Giyani Municipality","authors":"Tebogo J Lebea, N. Jovanović, M. Kena, K. Ayisi, Wisani G Mushadu","doi":"10.1080/02571862.2021.1913767","DOIUrl":"https://doi.org/10.1080/02571862.2021.1913767","url":null,"abstract":"Intensification of low-tech agricultural production is required in the Greater Giyani Municipality (Limpopo province, South Africa) to respond to changing climatic conditions, water scarcity and increased food demand of the local market. Two years of field experiments were conducted on two typical small-scale farms under real-world conditions. The objective was to test the response of locally available tomato (Lycopersicon esculentum Mill.) cultivars (Rodade, STAR 9006, Commander, HTX 14 and MFH) to two different irrigation strategies (full irrigation FI and deficit irrigation DI). While results showed high tomato yield variability (ranging between 9.2 t ha−1 and 59.7 t ha−1) depending on the farms, environmental conditions (heatwaves, diseases) and irrigation management, STAR 9006 appeared to be the best performing cultivar and HTX 14 the worst. Seasonal evapotranspiration under FI was between 400 and 620 mm depending on the length of the season and harvesting time. Crop water productivity was generally higher for DI than FI treatments. Deficit irrigation appeared to be feasible to reduce water use for some cultivars (eg cv. STAR 9006), however, an economic analysis should be conducted at specific sites/farms to determine the impacts of DI on farmers’ income as some yield losses can be expected during drought years.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48452124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1913249
L. van Straaten, CF Wessels, G. Ceronio, C. du Preez
The grain yield and quality of maize is often negatively influenced by zinc (Zn) deficiencies during early growth and development. Application of Zn to soil is therefore a necessity, especially when it is sandy. Glasshouse experiments were carried out to test the effects of Zn sources and application rates on plant-available Zn and on early growth and development of maize grown in a sandy soil. Soil Zn concentration was increased most by ZnSO4 and least by ZnO. The Na2EDTA method was superior to four other methods in extracting soil Zn. For most plant parameters that were measured (leaf number, stem thickness, plant height, photosynthesis rate, leaf area, dry mass, root length and root mass) ZnEDTA was the most effective chelated source, followed by ZnHEDTA, ZnDTPA or ZnEDDHA. Regarding inorganic sources ZnSO4 was superior, followed by ZnCO3, ZnCl2 and ZnO. As a group the inorganic sources performed more poorly than the chelated sources. These rankings differed in terms of Zn concentration and uptake by the plants. The results must be verified in field trials that last for several years accommodating a wider range of climate and soil conditions to develop reliable Zn fertilisation guidelines for maize cultivated on sandy soils.
{"title":"Early growth and development of maize on sandy soils fertilised with zinc sources at different application rates","authors":"L. van Straaten, CF Wessels, G. Ceronio, C. du Preez","doi":"10.1080/02571862.2021.1913249","DOIUrl":"https://doi.org/10.1080/02571862.2021.1913249","url":null,"abstract":"The grain yield and quality of maize is often negatively influenced by zinc (Zn) deficiencies during early growth and development. Application of Zn to soil is therefore a necessity, especially when it is sandy. Glasshouse experiments were carried out to test the effects of Zn sources and application rates on plant-available Zn and on early growth and development of maize grown in a sandy soil. Soil Zn concentration was increased most by ZnSO4 and least by ZnO. The Na2EDTA method was superior to four other methods in extracting soil Zn. For most plant parameters that were measured (leaf number, stem thickness, plant height, photosynthesis rate, leaf area, dry mass, root length and root mass) ZnEDTA was the most effective chelated source, followed by ZnHEDTA, ZnDTPA or ZnEDDHA. Regarding inorganic sources ZnSO4 was superior, followed by ZnCO3, ZnCl2 and ZnO. As a group the inorganic sources performed more poorly than the chelated sources. These rankings differed in terms of Zn concentration and uptake by the plants. The results must be verified in field trials that last for several years accommodating a wider range of climate and soil conditions to develop reliable Zn fertilisation guidelines for maize cultivated on sandy soils.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49461719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-08-08DOI: 10.1080/02571862.2021.1925761
Phomolo Maphothoma, R. Kleynhans, G. Prinsloo, S. Mokgehle, Ian du Plooy, H. Araya
African ginger (Siphonochilus aethiopicus) is in high demand for medicinal use. The plant does not multiply after being harvested, as it is destroyed in the process. The species is now facing extinction as a result of over harvesting. In order to mitigate this threat, cultivation of the species has become priority. The objective of this study was to determine the growth and yield parameters of S. aethiopicus in relation to organic fertiliser treatments. The parameters were evaluated in response to three organic fertiliser applications (0, 100 and 200 kg N ha−1) and three rhizome sizes, namely small (10–20 g), medium (20–40 g) and large (> 40 g). The combination of a fertiliser application of 100 kg N ha−1 and large rhizomes provided the best results, with maxima for rhizome yield (7 t ha−1) and root yield (6 t ha−1). Small and medium rhizomes had a significantly lower yield than large rhizomes at all nitrogen levels. The different fertiliser applications were associated with significant variation in leaf chlorophyll content. It is concluded that the application of 100 kg N ha−1 and planting of large rhizomes would result in the best yield for African ginger’s commercial production.
非洲生姜（Siphonchilus aethiopicus）在药用方面需求量很大。这种植物在收获后不会繁殖，因为它在这个过程中被破坏了。由于过度捕捞，该物种现在正面临灭绝。为了减轻这种威胁，培育该物种已成为当务之急。本研究的目的是确定与有机肥料处理相关的醚硫草的生长和产量参数。根据三种有机肥料（0、100和200 kg N ha−1）和三种根茎大小（即小根茎（10-20 g）、中根茎（20-40 g）和大根茎（>40 g））对参数进行了评估。施用100 kg N ha−1的化肥和大根状茎的组合效果最好，根状茎产量（7 t ha−1）和根产量（6 t ha−2）最高。在所有氮水平下，中小根状茎的产量都显著低于大根状茎。不同的施肥方式与叶片叶绿素含量的显著变化有关。结果表明，施用100kg N ha−1和种植大根状茎将为非洲生姜的商业生产带来最佳产量。
{"title":"Growth and yield of African ginger in response to application of organic fertiliser","authors":"Phomolo Maphothoma, R. Kleynhans, G. Prinsloo, S. Mokgehle, Ian du Plooy, H. Araya","doi":"10.1080/02571862.2021.1925761","DOIUrl":"https://doi.org/10.1080/02571862.2021.1925761","url":null,"abstract":"African ginger (Siphonochilus aethiopicus) is in high demand for medicinal use. The plant does not multiply after being harvested, as it is destroyed in the process. The species is now facing extinction as a result of over harvesting. In order to mitigate this threat, cultivation of the species has become priority. The objective of this study was to determine the growth and yield parameters of S. aethiopicus in relation to organic fertiliser treatments. The parameters were evaluated in response to three organic fertiliser applications (0, 100 and 200 kg N ha−1) and three rhizome sizes, namely small (10–20 g), medium (20–40 g) and large (> 40 g). The combination of a fertiliser application of 100 kg N ha−1 and large rhizomes provided the best results, with maxima for rhizome yield (7 t ha−1) and root yield (6 t ha−1). Small and medium rhizomes had a significantly lower yield than large rhizomes at all nitrogen levels. The different fertiliser applications were associated with significant variation in leaf chlorophyll content. It is concluded that the application of 100 kg N ha−1 and planting of large rhizomes would result in the best yield for African ginger’s commercial production.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44889439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-27DOI: 10.1080/02571862.2021.1979112
J. Strauss, Paul Swanepoel, H. Smith, EH Smit
Conservation Agriculture (CA) is a holistic farming system aimed at the conservation of natural resources by halting soil erosion and increasing biodiversity in cropping systems, while still effecting sustainable production. Conservation agriculture is based on three principles, namely minimum soil disturbance, diversity through crop rotation and permanent organic soil cover. The system has shown remarkable growth over the last few decades worldwide, as well as in South Africa. As there are numerous benefits, CA is viewed by many as the more sustainable alternative to conventional agricultural practice. A pragmatic approach, however, should be taken to combat the challenges associated with CA. This paper provides a brief explanation of the basic principles of CA, provides a brief history of the implementation of conservation agriculture in South Africa and provides a discussion of the benefits and challenges associated with the approach. This paper also serves as an introduction to a Special Issue on conservation agriculture in South Africa.
{"title":"A history of Conservation Agriculture in South Africa","authors":"J. Strauss, Paul Swanepoel, H. Smith, EH Smit","doi":"10.1080/02571862.2021.1979112","DOIUrl":"https://doi.org/10.1080/02571862.2021.1979112","url":null,"abstract":"Conservation Agriculture (CA) is a holistic farming system aimed at the conservation of natural resources by halting soil erosion and increasing biodiversity in cropping systems, while still effecting sustainable production. Conservation agriculture is based on three principles, namely minimum soil disturbance, diversity through crop rotation and permanent organic soil cover. The system has shown remarkable growth over the last few decades worldwide, as well as in South Africa. As there are numerous benefits, CA is viewed by many as the more sustainable alternative to conventional agricultural practice. A pragmatic approach, however, should be taken to combat the challenges associated with CA. This paper provides a brief explanation of the basic principles of CA, provides a brief history of the implementation of conservation agriculture in South Africa and provides a discussion of the benefits and challenges associated with the approach. This paper also serves as an introduction to a Special Issue on conservation agriculture in South Africa.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48850163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：