Pub Date : 2022-05-27DOI: 10.1080/02571862.2022.2078516
Jacobus FN Smith, A. Hardie
Despite the global importance of rooibos tea (Aspalathus linearis (Burm.f.) R.Dahlgren) as a health-promoting crop, foliar nutrient sufficiency ranges have not yet been determined for commercially cultivated rooibos. Determination of these ranges is critical for assessing plant nutrient status and maximising productivity. The aim of this study was to determine optimal rooibos foliar macro- and micronutrient ranges using the boundary-line approach (BLA) method across the main rooibos production areas in South Africa. Foliar nutrient and yield data were collected from 120 different commercial rooibos plantations in the six main rooibos producing areas of the country: Nardouwsberg/ Agterpakhuys, Clanwilliam, Gifberg/ Vanrhynsdorp, Nieuwoudtville, Citrusdal and Sandveld. The BLA-derived optimum (late winter) rooibos foliar macronutrient and 90%-yield sufficiency range concentrations (%) were: 1.55 (1.30–1.80) for N, 0.12 (0.09–0.14) for P, 0.54 (0.34–0.75) for K, 0.20 (0.14–0.26) for Ca, 0.22 (0.19–0.25) for Mg, and 0.10 (0.08–0.11) for S. Optimum micronutrient contents and ranges (mg kg−1) were: 85.8 (57.6–114.1) for Fe, 58.2 (26.9–113.8) for Mn, 16.6 (12.7–20.5) for Zn, 2.8 (1.3–4.2) for Cu, and 26.9 (21.8–32.0) for B. Maintaining foliar nutrient concentrations within these ranges will support maximal yields (1 200 kg ha−1). The foliar nutrient guidelines are of importance for enhancing sustainable rooibos production in South Africa.
尽管rooibos茶（Asplatus linearis（Burm.f.）R.Dahlgren）作为一种促进健康的作物在全球具有重要意义，但商业种植的rooibos的叶面营养充足范围尚未确定。确定这些范围对于评估植物营养状况和最大限度地提高生产力至关重要。本研究的目的是使用边界线法（BLA）确定南非主要鲁伊博产区的最佳鲁伊博叶片宏观和微量营养素范围。从该国六个主要菜豆产区的120个不同的商业菜豆种植园收集了叶片营养和产量数据：Nardouwsberg/Agterpakhuys、Clanwilliam、Gifberg/Vanrhynsdorp、Nieuwudtville、Citrusdal和Sandveld。BLA得出的最佳（晚冬）菜油叶大量营养素和90%产量充足度范围浓度（%）为：N为1.55（1.30–1.80），P为0.12（0.09–0.14），K为0.54（0.34–0.75），Ca为0.20（0.14–0.26），Mg为0.22（0.19–0.25），S为0.10（0.08–0.11）。最佳微量营养素含量和范围（Mg kg−1）为：Fe为85.8（57.6–114.1），Mn为58.2（26.9–113.8），Zn为16.6（12.7–20.5），Cu为2.8（1.3–4.2），B为26.9（21.8–32.0）。将叶面养分浓度保持在这些范围内将支持最大产量（1200 kg ha−1）。叶面营养指南对提高南非的可持续鲁伊博生产具有重要意义。
{"title":"Determination of foliar nutrient sufficiency ranges in cultivated rooibos tea using the boundary-line approach","authors":"Jacobus FN Smith, A. Hardie","doi":"10.1080/02571862.2022.2078516","DOIUrl":"https://doi.org/10.1080/02571862.2022.2078516","url":null,"abstract":"Despite the global importance of rooibos tea (Aspalathus linearis (Burm.f.) R.Dahlgren) as a health-promoting crop, foliar nutrient sufficiency ranges have not yet been determined for commercially cultivated rooibos. Determination of these ranges is critical for assessing plant nutrient status and maximising productivity. The aim of this study was to determine optimal rooibos foliar macro- and micronutrient ranges using the boundary-line approach (BLA) method across the main rooibos production areas in South Africa. Foliar nutrient and yield data were collected from 120 different commercial rooibos plantations in the six main rooibos producing areas of the country: Nardouwsberg/ Agterpakhuys, Clanwilliam, Gifberg/ Vanrhynsdorp, Nieuwoudtville, Citrusdal and Sandveld. The BLA-derived optimum (late winter) rooibos foliar macronutrient and 90%-yield sufficiency range concentrations (%) were: 1.55 (1.30–1.80) for N, 0.12 (0.09–0.14) for P, 0.54 (0.34–0.75) for K, 0.20 (0.14–0.26) for Ca, 0.22 (0.19–0.25) for Mg, and 0.10 (0.08–0.11) for S. Optimum micronutrient contents and ranges (mg kg−1) were: 85.8 (57.6–114.1) for Fe, 58.2 (26.9–113.8) for Mn, 16.6 (12.7–20.5) for Zn, 2.8 (1.3–4.2) for Cu, and 26.9 (21.8–32.0) for B. Maintaining foliar nutrient concentrations within these ranges will support maximal yields (1 200 kg ha−1). The foliar nutrient guidelines are of importance for enhancing sustainable rooibos production in South Africa.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"226 - 233"},"PeriodicalIF":0.9,"publicationDate":"2022-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44619548","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 : 2022-05-27DOI: 10.1080/02571862.2022.2068084
Vhuthu Ndou, E. Phiri, P. Pieterse
Herbicide mixtures are beneficial since they delay the occurrence of resistance to herbicides, provided that the herbicides used are effective at controlling the target weed species. Recently, plantago (Plantago lanceolata L.) was found to show 23 and 10-fold-resistance to glyphosate and paraquat. Experiments were carried out under controlled conditions to determine the efficacy of various herbicide concentrations and mixtures for the control of multiple resistant plantago at the two to three leaf stage. Proven plantago resistant (R) biotypes which had been shown to survive high glyphosate and paraquat dosages were used together with one susceptible (S) biotype in each experiment. The herbicides 2-methyl-4-chlorophenoxyacetic acid (MCPA), (400 g a.i. ha−1), carfentrazone-ethyl (400 g a.i. ha−1), and glufosinate (200 g a.i. ha−1), and two combined mixtures consisting of paraquat + diquat (120 + 80 g a.i. ha−1), and terbuthylazine + S-metolachlor (497.2 + 102.8 g a.i. ha−1) were applied either alone or in mixtures resulting in 12 treatments. The herbicides and combinations were chosen for their distinct modes of action. The mixtures achieved 0% survival rates for the R and S biotypes except for glyphosate + MCPA and MCPA applied alone. The herbicide mixtures identified in the study together with other non-chemical control options may be used in the management of glyphosate- and paraquat-resistant plantago infestations.
除草剂混合物是有益的，因为它们延缓了对除草剂产生抗性的发生，只要所使用的除草剂能有效地控制目标杂草种类。最近发现车前草(plantago lanceolata L.)对草甘膦和百草枯的抗性分别为23倍和10倍。在一定条件下进行了不同除草剂浓度和混合药剂对车前草二、三叶期多重抗性的防治效果试验。已证实的车前草抗性(R)生物型在高草甘膦和百草枯剂量下存活，在每个实验中与一种敏感(S)生物型一起使用。除草剂2-甲基-4-氯苯氧乙酸(MCPA) (400 g a.i. ha−1)、卡芬曲酮-乙基(400 g a.i. ha−1)和草铵膦(200 g a.i. ha−1)，以及由百草枯+双甘菊(120 + 80 g a.i. ha−1)和特丁基嗪+ s -甲草胺(497.2 + 102.8 g a.i. ha−1)组成的两种组合混合物单独或混合施用，共12次处理。所选择的除草剂和组合是根据其不同的作用方式选择的。除草甘膦+ MCPA和单独使用MCPA外，R和S生物型的混合物存活率均为0%。研究中确定的混合除草剂与其他非化学控制方法可用于管理抗草甘膦和百草枯的车前草虫害。
{"title":"Screening herbicides and herbicide mixtures to identify alternative chemical controls for resistant plantago biotypes","authors":"Vhuthu Ndou, E. Phiri, P. Pieterse","doi":"10.1080/02571862.2022.2068084","DOIUrl":"https://doi.org/10.1080/02571862.2022.2068084","url":null,"abstract":"Herbicide mixtures are beneficial since they delay the occurrence of resistance to herbicides, provided that the herbicides used are effective at controlling the target weed species. Recently, plantago (Plantago lanceolata L.) was found to show 23 and 10-fold-resistance to glyphosate and paraquat. Experiments were carried out under controlled conditions to determine the efficacy of various herbicide concentrations and mixtures for the control of multiple resistant plantago at the two to three leaf stage. Proven plantago resistant (R) biotypes which had been shown to survive high glyphosate and paraquat dosages were used together with one susceptible (S) biotype in each experiment. The herbicides 2-methyl-4-chlorophenoxyacetic acid (MCPA), (400 g a.i. ha−1), carfentrazone-ethyl (400 g a.i. ha−1), and glufosinate (200 g a.i. ha−1), and two combined mixtures consisting of paraquat + diquat (120 + 80 g a.i. ha−1), and terbuthylazine + S-metolachlor (497.2 + 102.8 g a.i. ha−1) were applied either alone or in mixtures resulting in 12 treatments. The herbicides and combinations were chosen for their distinct modes of action. The mixtures achieved 0% survival rates for the R and S biotypes except for glyphosate + MCPA and MCPA applied alone. The herbicide mixtures identified in the study together with other non-chemical control options may be used in the management of glyphosate- and paraquat-resistant plantago infestations.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"198 - 203"},"PeriodicalIF":0.9,"publicationDate":"2022-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41442956","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 : 2022-05-27DOI: 10.1080/02571862.2022.2070935
Emc Theron, S. Magano
Tick infestations and tick-borne diseases continue to be the leading causes of loss in livestock and revenue, particularly in developing countries, despite the prevalent use of synthetic acaricides. Research on plants as alternative sources of anti-arthropod agents has received attention from many researchers in the recent past. This interest is mainly motivated by the compelling need to move away from over-reliance on anti-arthropod synthetic chemicals, which have harmful effects on the environment and livestock. While many plants have been shown to possess anti-tick properties, such studies are in the main laboratory-based and thus their effects cannot be accounted for in the natural environments. Furthermore, knowledge on the mechanisms by which plant extracts impact ticks is sparse and not coordinated for ease of reference. The literature explored in this study was collected from indices included in the University of South Africa (UNISA) library database following keyword searches on plant extracts used as tick control methods and reviews. This article provides a consolidation of literature on the anti-tick properties of plant-based material and their prospects for being integrated with current tick control methods.
{"title":"A reflection on tick control and the potential role of botanical products in integrated management practices","authors":"Emc Theron, S. Magano","doi":"10.1080/02571862.2022.2070935","DOIUrl":"https://doi.org/10.1080/02571862.2022.2070935","url":null,"abstract":"Tick infestations and tick-borne diseases continue to be the leading causes of loss in livestock and revenue, particularly in developing countries, despite the prevalent use of synthetic acaricides. Research on plants as alternative sources of anti-arthropod agents has received attention from many researchers in the recent past. This interest is mainly motivated by the compelling need to move away from over-reliance on anti-arthropod synthetic chemicals, which have harmful effects on the environment and livestock. While many plants have been shown to possess anti-tick properties, such studies are in the main laboratory-based and thus their effects cannot be accounted for in the natural environments. Furthermore, knowledge on the mechanisms by which plant extracts impact ticks is sparse and not coordinated for ease of reference. The literature explored in this study was collected from indices included in the University of South Africa (UNISA) library database following keyword searches on plant extracts used as tick control methods and reviews. This article provides a consolidation of literature on the anti-tick properties of plant-based material and their prospects for being integrated with current tick control methods.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"213 - 225"},"PeriodicalIF":0.9,"publicationDate":"2022-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47694541","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 : 2022-03-15DOI: 10.1080/02571862.2022.2037165
Nokuthula Hlanga, A. Modi, I. Mathew
Assessing agro-morphological variation is important for crop improvement strategies in cultivated species. Bambara groundnut (Vigna subterranea (L.) Verdc.) is a neglected crop that requires extensive agro-morphological characterisation to design suitable agronomic and crop improvement strategies. Nineteen Bambara groundnut lines were evaluated at two sites for agro-morphological traits in 2017 and 2018. The experiments were laid out as a split-split plot completely randomised design with three replications. The lines showed significant differences (p < 0.05) for all the traits except chlorophyll content and stomatal conductance. The observed genotypic differences would be useful for Bambara groundnut improvement if they are underpinned by genetic differences for recombination. Principal components 1 and 2 accounted for 52.31% of the variation showing that agro-morphological traits alone could not adequately discriminate between the Bambara groundnut lines. The most useful traits were root and shoot mass, plant height and leaf number. The negative and unfavourable correlations between seedling emergency and chlorophyll would complicate simultaneous selection for these traits during Bambara groundnut improvement. However, genetic dissimilarity indices indicated that there was genetic variation within the germplasm, which is important for Bambara groundnut improvement. Lines Kenya Capstone, Uniswa-Red-G, Uniswa-Red-R and KANO2 were selected for breeding and recommended for production due to their high performance in several key traits.
{"title":"Agro-morphological diversity of Bambara groundnut lines evaluated under field conditions","authors":"Nokuthula Hlanga, A. Modi, I. Mathew","doi":"10.1080/02571862.2022.2037165","DOIUrl":"https://doi.org/10.1080/02571862.2022.2037165","url":null,"abstract":"Assessing agro-morphological variation is important for crop improvement strategies in cultivated species. Bambara groundnut (Vigna subterranea (L.) Verdc.) is a neglected crop that requires extensive agro-morphological characterisation to design suitable agronomic and crop improvement strategies. Nineteen Bambara groundnut lines were evaluated at two sites for agro-morphological traits in 2017 and 2018. The experiments were laid out as a split-split plot completely randomised design with three replications. The lines showed significant differences (p < 0.05) for all the traits except chlorophyll content and stomatal conductance. The observed genotypic differences would be useful for Bambara groundnut improvement if they are underpinned by genetic differences for recombination. Principal components 1 and 2 accounted for 52.31% of the variation showing that agro-morphological traits alone could not adequately discriminate between the Bambara groundnut lines. The most useful traits were root and shoot mass, plant height and leaf number. The negative and unfavourable correlations between seedling emergency and chlorophyll would complicate simultaneous selection for these traits during Bambara groundnut improvement. However, genetic dissimilarity indices indicated that there was genetic variation within the germplasm, which is important for Bambara groundnut improvement. Lines Kenya Capstone, Uniswa-Red-G, Uniswa-Red-R and KANO2 were selected for breeding and recommended for production due to their high performance in several key traits.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"142 - 152"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41637862","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 : 2022-03-15DOI: 10.1080/02571862.2022.2056644
Shimbahri Mesfin, H. Haileselassie
Agroforestry tree species play an important role in improving soil fertility. Though studies have confirmed that different species show different potentials to improve soil fertility, it is difficult to compare them as the studies were conducted in different areas. The potential for different tree species to improve soil fertility on croplands in northern Ethiopia is not known. The objectives of this paper are to determine the effects of presence or absence of agroforestry tree species on soil physico-chemical properties and the effect of distance from the tree trunk on the same soil physico-chemical properties. Sixty composite and undisturbed soil samples from beneath canopies and outside canopies and 90 composite and undisturbed soil samples from three different distances from tree trunks were collected. The results revealed that soil bulk density, soil moisture, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (Av.P), exchangeable potassium (Exch.K) and soil organic carbon stock (SOCS) were significantly (p < 0.05) different between soils beneath canopies and outside canopies as well as at different distances from the tree trunk. Soils around these agroforestry tree species have increased SOC, TN, Av.P, Exch.K and SOCS by 11.9 to 91.5%, 22.2 to 125.0%, 31 to 71%, 32 to 151.6% and 15.2 to 90.9%, respectively, compared to soils outside tree canopies. Faidherbia albida (Delile) A.Chev. has the highest potential for soil fertility compared to Balanites aegyptiaca (L.) Delile, Cordia africana Lam., Ziziphus spina-christi (L.) Desf., Acacia sieberiana DC and Croton macrostachyus Hochst. ex Delile. This study could provide useful information for soil fertility management and farmers’ decision-making when selecting tree species. The findings of this study imply that scattered trees on croplands significantly improve soil fertility and reduce the need for external fertiliser inputs.
{"title":"Evaluation of soil physico-chemical properties as affected by canopies of scattered agroforestry trees on croplands","authors":"Shimbahri Mesfin, H. Haileselassie","doi":"10.1080/02571862.2022.2056644","DOIUrl":"https://doi.org/10.1080/02571862.2022.2056644","url":null,"abstract":"Agroforestry tree species play an important role in improving soil fertility. Though studies have confirmed that different species show different potentials to improve soil fertility, it is difficult to compare them as the studies were conducted in different areas. The potential for different tree species to improve soil fertility on croplands in northern Ethiopia is not known. The objectives of this paper are to determine the effects of presence or absence of agroforestry tree species on soil physico-chemical properties and the effect of distance from the tree trunk on the same soil physico-chemical properties. Sixty composite and undisturbed soil samples from beneath canopies and outside canopies and 90 composite and undisturbed soil samples from three different distances from tree trunks were collected. The results revealed that soil bulk density, soil moisture, soil organic carbon (SOC), total nitrogen (TN), available phosphorus (Av.P), exchangeable potassium (Exch.K) and soil organic carbon stock (SOCS) were significantly (p < 0.05) different between soils beneath canopies and outside canopies as well as at different distances from the tree trunk. Soils around these agroforestry tree species have increased SOC, TN, Av.P, Exch.K and SOCS by 11.9 to 91.5%, 22.2 to 125.0%, 31 to 71%, 32 to 151.6% and 15.2 to 90.9%, respectively, compared to soils outside tree canopies. Faidherbia albida (Delile) A.Chev. has the highest potential for soil fertility compared to Balanites aegyptiaca (L.) Delile, Cordia africana Lam., Ziziphus spina-christi (L.) Desf., Acacia sieberiana DC and Croton macrostachyus Hochst. ex Delile. This study could provide useful information for soil fertility management and farmers’ decision-making when selecting tree species. The findings of this study imply that scattered trees on croplands significantly improve soil fertility and reduce the need for external fertiliser inputs.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"153 - 162"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46394393","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 : 2022-03-15DOI: 10.1080/02571862.2021.2009049
LS Tlomatsana, PF Loke, E. Kotzé, MP Aghoghovwia
Soil aggregate dynamics have received renewed interest due to their relevance in carbon (C) stabilisation. This study evaluated changes in aggregate-size distribution and intra-aggregate C following 41 years of wheat production in semi-arid central South Africa. Management practices that have been applied for 41 years include two straw management protocols (unburned and burned), three tillage systems (no-tillage, stubble mulch and mouldboard ploughing) and two weeding methods (chemical and mechanical). Soil cores were taken at 0–10 cm and 10–20 cm depths and fractionated to aggregates of different sizes using wet sieving. All the fractions including bulk soil were analysed for C. Unburned plots had more small macro-aggregates (35% and 33%, respectively) in the 0–10 cm and 10–20 cm depths, but 26% and 27% lower large macro-aggregate and bulk C, respectively were found in the 10–20 cm depth compared to the burned plots. No-tillage stimulated re-aggregation, especially large macro-aggregates, by 68% in the 0–10 cm depth compared to stubble mulch. Small macro-aggregates, large micro-aggregates and bulk soil under no-tillage had on average 25% higher C compared to those under mouldboard ploughing in the 0–10 cm soil layer. Although signs of aggregate equilibrium state were evident, future studies focusing specifically on this subject are needed.
{"title":"Aggregate dynamics and intra-aggregate carbon contents as influenced by long-term wheat production management in semi-arid South Africa","authors":"LS Tlomatsana, PF Loke, E. Kotzé, MP Aghoghovwia","doi":"10.1080/02571862.2021.2009049","DOIUrl":"https://doi.org/10.1080/02571862.2021.2009049","url":null,"abstract":"Soil aggregate dynamics have received renewed interest due to their relevance in carbon (C) stabilisation. This study evaluated changes in aggregate-size distribution and intra-aggregate C following 41 years of wheat production in semi-arid central South Africa. Management practices that have been applied for 41 years include two straw management protocols (unburned and burned), three tillage systems (no-tillage, stubble mulch and mouldboard ploughing) and two weeding methods (chemical and mechanical). Soil cores were taken at 0–10 cm and 10–20 cm depths and fractionated to aggregates of different sizes using wet sieving. All the fractions including bulk soil were analysed for C. Unburned plots had more small macro-aggregates (35% and 33%, respectively) in the 0–10 cm and 10–20 cm depths, but 26% and 27% lower large macro-aggregate and bulk C, respectively were found in the 10–20 cm depth compared to the burned plots. No-tillage stimulated re-aggregation, especially large macro-aggregates, by 68% in the 0–10 cm depth compared to stubble mulch. Small macro-aggregates, large micro-aggregates and bulk soil under no-tillage had on average 25% higher C compared to those under mouldboard ploughing in the 0–10 cm soil layer. Although signs of aggregate equilibrium state were evident, future studies focusing specifically on this subject are needed.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"94 - 101"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46315934","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 : 2022-03-15DOI: 10.1080/02571862.2022.2050316
Mekedes Lulu, Bekele Lemma, Legesse Hidoto, A. Melese
This study assessed the effect of the interactions of biochar (BC), farmyard manure (FYM) and lime on soil chemical properties, and on different wheat attributes in Southern Ethiopia. The experimental design was a randomised complete block in three replications. The site significantly (p ≤ 0.05) influenced soil and wheat attributes. Biochar showed a large significant effect (p ≤ 0.05) on soil organic carbon, cation exchange capacity, and exchangeable potassium (K) while lime showed a substantially significant (p ≤ 0.05) effect on exchangeable Calcium (Ca)and acidity. Farmyard manure (10 tonnes ha−1) had a significant effect on soil total nitrogen (TN). Biochar and lime showed a large significant effect on soil pH and available phosphorus (P) depending on the site. All amendments showed a significant (p ≤ 0.001) effect on most wheat attributes, but the highest effect was from BC. Biochar produced highly significant (p ≤ 0.001) effects on plant height, total number of tillers and productive tillers, number of seeds per spike, aboveground biomass, grain yield, and P and K content in wheat grain and straw. We accredited the greater effect of BC on wheat attributes to its influence on soil chemical properties. We recommend long-term studies on the impact of BC alone or in combination with FYM on acid soil types.
{"title":"Effect of biochar, farmyard manure, and lime on soil properties, and on growth and nutrient uptake of wheat on acidic soils in Southern Ethiopia","authors":"Mekedes Lulu, Bekele Lemma, Legesse Hidoto, A. Melese","doi":"10.1080/02571862.2022.2050316","DOIUrl":"https://doi.org/10.1080/02571862.2022.2050316","url":null,"abstract":"This study assessed the effect of the interactions of biochar (BC), farmyard manure (FYM) and lime on soil chemical properties, and on different wheat attributes in Southern Ethiopia. The experimental design was a randomised complete block in three replications. The site significantly (p ≤ 0.05) influenced soil and wheat attributes. Biochar showed a large significant effect (p ≤ 0.05) on soil organic carbon, cation exchange capacity, and exchangeable potassium (K) while lime showed a substantially significant (p ≤ 0.05) effect on exchangeable Calcium (Ca)and acidity. Farmyard manure (10 tonnes ha−1) had a significant effect on soil total nitrogen (TN). Biochar and lime showed a large significant effect on soil pH and available phosphorus (P) depending on the site. All amendments showed a significant (p ≤ 0.001) effect on most wheat attributes, but the highest effect was from BC. Biochar produced highly significant (p ≤ 0.001) effects on plant height, total number of tillers and productive tillers, number of seeds per spike, aboveground biomass, grain yield, and P and K content in wheat grain and straw. We accredited the greater effect of BC on wheat attributes to its influence on soil chemical properties. We recommend long-term studies on the impact of BC alone or in combination with FYM on acid soil types.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"112 - 122"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43132025","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 : 2022-03-15DOI: 10.1080/02571862.2022.2038711
S. Mthimkhulu, D. Elephant, N. Miles, L. Titshall
This study investigated the effects of surface-application of lime and gypsum on soil properties and yields of ratoon sugarcane crops. Treatments involved once-off surface application of dolomitic lime (L), gypsum (G) and dolomitic lime plus gypsum (LG) in factorial combination, with four replications. Soil chemical properties were measured on samples collected at intervals of 20 between depths of 0 and 80 cm in the first and fifth years after treatment application. Yield parameters were measured annually. In the first year, treatment effects were mainly restricted to a depth of 0–20 cm. The LG increased pH(CaCl2) from 3.9 to 4.5, and calcium from 123 to 350 mg L−1. Little treatment effect was observed on yield parameters in the first year. In the fifth year, L and LG generally showed similar impacts on soil properties. The L treatment led to markedly increased pH(CaCl2) and calcium and somewhat decreased magnesium levels in the topsoil. The sucrose and cane yields in LG were significantly higher than in other treatments, which all had similar results. It was, therefore, concluded that LG may be a viable option for the correction of soil acidity through surface application in the sugarcane ratoon crops grown in the sandy soils of KwaZulu-Natal.
{"title":"The short-term effects of surface-applied dolomitic lime and gypsum on soil chemical properties and yields of sugarcane ratoon crops in KwaZulu-Natal, South Africa","authors":"S. Mthimkhulu, D. Elephant, N. Miles, L. Titshall","doi":"10.1080/02571862.2022.2038711","DOIUrl":"https://doi.org/10.1080/02571862.2022.2038711","url":null,"abstract":"This study investigated the effects of surface-application of lime and gypsum on soil properties and yields of ratoon sugarcane crops. Treatments involved once-off surface application of dolomitic lime (L), gypsum (G) and dolomitic lime plus gypsum (LG) in factorial combination, with four replications. Soil chemical properties were measured on samples collected at intervals of 20 between depths of 0 and 80 cm in the first and fifth years after treatment application. Yield parameters were measured annually. In the first year, treatment effects were mainly restricted to a depth of 0–20 cm. The LG increased pH(CaCl2) from 3.9 to 4.5, and calcium from 123 to 350 mg L−1. Little treatment effect was observed on yield parameters in the first year. In the fifth year, L and LG generally showed similar impacts on soil properties. The L treatment led to markedly increased pH(CaCl2) and calcium and somewhat decreased magnesium levels in the topsoil. The sucrose and cane yields in LG were significantly higher than in other treatments, which all had similar results. It was, therefore, concluded that LG may be a viable option for the correction of soil acidity through surface application in the sugarcane ratoon crops grown in the sandy soils of KwaZulu-Natal.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"102 - 111"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47426682","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 : 2022-03-15DOI: 10.1080/02571862.2021.2001598
J. Strauss, K. Truter, P. Swanepoel
A seed-drill should facilitate seed placement in an environment conducive to uniform seedling emergence. In semi-arid rain-fed production regions, low rainfall intensity and erratic rainfall events can result in non-uniform emergence. Evaluation of seed-drills is necessary to supply small grain producers with potential solutions to combat non-uniform seedling emergence. The aim of this study was to investigate the influence of three seed-drills on seeding depth, crop emergence, biomass production and yield over the duration of two growing seasons. Barley, canola and wheat were established with three seed-drills, each equipped with a different opener. Seed-drills contained either double disc openers, tine openers, or a combination of both tines and single discs. Crops responded variably to seeding equipment under different climatic conditions. For example, accuracy of seeding depth varied between the three seed-drills utilised. Seed-drills, together with their associated seed placement characteristics, influenced crop emergence. Biomass production was variable over the course of the growing season. Biomass production of crops established with the double disc seed-drill tended to be higher than that of crops established with tine seed-drills. Additional research about adaptations of agronomic practices and seed-drill openers may increase resilience to adverse climatic conditions in semi-arid small grain production regions. Various factors, including soil physical conditions, environmental conditions, economic feasibility and practical applications must be taken into consideration when selecting a seed-drill.
{"title":"The influence of seed-drill choice on crop performance in a semi-arid production region of South Africa","authors":"J. Strauss, K. Truter, P. Swanepoel","doi":"10.1080/02571862.2021.2001598","DOIUrl":"https://doi.org/10.1080/02571862.2021.2001598","url":null,"abstract":"A seed-drill should facilitate seed placement in an environment conducive to uniform seedling emergence. In semi-arid rain-fed production regions, low rainfall intensity and erratic rainfall events can result in non-uniform emergence. Evaluation of seed-drills is necessary to supply small grain producers with potential solutions to combat non-uniform seedling emergence. The aim of this study was to investigate the influence of three seed-drills on seeding depth, crop emergence, biomass production and yield over the duration of two growing seasons. Barley, canola and wheat were established with three seed-drills, each equipped with a different opener. Seed-drills contained either double disc openers, tine openers, or a combination of both tines and single discs. Crops responded variably to seeding equipment under different climatic conditions. For example, accuracy of seeding depth varied between the three seed-drills utilised. Seed-drills, together with their associated seed placement characteristics, influenced crop emergence. Biomass production was variable over the course of the growing season. Biomass production of crops established with the double disc seed-drill tended to be higher than that of crops established with tine seed-drills. Additional research about adaptations of agronomic practices and seed-drill openers may increase resilience to adverse climatic conditions in semi-arid small grain production regions. Various factors, including soil physical conditions, environmental conditions, economic feasibility and practical applications must be taken into consideration when selecting a seed-drill.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"85 - 93"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42283925","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 : 2022-03-15DOI: 10.1080/02571862.2021.2000051
G. Ceronio, J. V. Van Tonder, C. du Preez
Commercial humates manufactured from oxidised lignites are often recommended to improve soil condition and crop growth. The benefits ascribed to these products are questioned, since they differ from humates that exist naturally in soils. Growth chamber, glasshouse and field experiments were conducted at facilities of the University of the Free State to quantify the influence of three potassium (K)-humate products on irrigated wheat growth and development, in loamy sand, sandy clay loam and clay loam soils. The humate products were applied to the soils at rates prescribed by their promoters. Results showed that the K humates were not beneficial for wheat growth and development as indicated by above-ground and subsoil plant parameters at tillering, stem elongation and maturity. However, the application of the K-humates caused higher bacteria and fungi counts in soil, which differed between the products applied. Despite the higher counts of bacteria and fungi in soil, grain yields were not affected, probably because no improvement in soil chemical properties were observed. Therefore, the application of K-humate products is not necessarily economically viable since they are relatively expensive. However, foliar applications of K humates may have stimulatory effects on wheat growth and development, resulting in better grain yields that could justify the higher production cost. An investigation into this aspect is suggested.
{"title":"Is application of commercial potassium humates beneficial to soil and wheat?","authors":"G. Ceronio, J. V. Van Tonder, C. du Preez","doi":"10.1080/02571862.2021.2000051","DOIUrl":"https://doi.org/10.1080/02571862.2021.2000051","url":null,"abstract":"Commercial humates manufactured from oxidised lignites are often recommended to improve soil condition and crop growth. The benefits ascribed to these products are questioned, since they differ from humates that exist naturally in soils. Growth chamber, glasshouse and field experiments were conducted at facilities of the University of the Free State to quantify the influence of three potassium (K)-humate products on irrigated wheat growth and development, in loamy sand, sandy clay loam and clay loam soils. The humate products were applied to the soils at rates prescribed by their promoters. Results showed that the K humates were not beneficial for wheat growth and development as indicated by above-ground and subsoil plant parameters at tillering, stem elongation and maturity. However, the application of the K-humates caused higher bacteria and fungi counts in soil, which differed between the products applied. Despite the higher counts of bacteria and fungi in soil, grain yields were not affected, probably because no improvement in soil chemical properties were observed. Therefore, the application of K-humate products is not necessarily economically viable since they are relatively expensive. However, foliar applications of K humates may have stimulatory effects on wheat growth and development, resulting in better grain yields that could justify the higher production cost. An investigation into this aspect is suggested.","PeriodicalId":21920,"journal":{"name":"South African Journal of Plant and Soil","volume":"39 1","pages":"123 - 131"},"PeriodicalIF":0.9,"publicationDate":"2022-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41420775","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}
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