Pub Date : 2024-01-16DOI: 10.3389/fagro.2023.1330222
Marian Malte Weigel, Therese With Berge, Jukka Salonen, T. Lötjönen, Bärbel Gerowitt, L. Brandsæter
Controlling creeping perennial weeds is challenging throughout all farming systems. The present study distinguished and explored three different methods to control them non-chemically: disturbance with inversion, disturbance without inversion, and competition. Focusing on Cirsium arvense, Elymus repens, and Sonchus arvensis, we conducted a field study (2019–2021) at three northern European sites in Germany, Finland, and Norway. We investigated the effects of the control methods ploughing (inversion disturbance), root cutting (non-inversion disturbance), and cover crops (competition) alone. Root cutting was conducted using a prototype machine developed by “Kverneland”. Eight treatments were tested in factorial designs adapted for each site. Control methods were applied solely and combined. Response variables after treatments were aboveground weed biomass and grain yield of spring cereals. The control method of ploughing was most effective in reducing weed biomass compared to root cutting or cover crops. However, compared to the untreated control, a pronounced additive effect of root cutting and cover crops occurred, reducing weed biomass (−57.5%) similar to ploughing (−66%). Pooled over sites, the response was species-specific, with each species showing a distinct reaction to both control methods. C. arvense was most susceptible to root cutting, followed by E. repens, while S. arvensis showed no susceptibility. Crop yield losses were prevented compared to untreated plots by ploughing (+60.57%) and root cutting (+30%), but not by cover crops. We conclude that the combination of non-inversion disturbance and competition is a promising strategy to reduce the reliance on herbicides or inversion tillage in the management of perennial weeds.
{"title":"Combining disturbance and competition to control creeping perennial weeds in a field study on three northern European sites","authors":"Marian Malte Weigel, Therese With Berge, Jukka Salonen, T. Lötjönen, Bärbel Gerowitt, L. Brandsæter","doi":"10.3389/fagro.2023.1330222","DOIUrl":"https://doi.org/10.3389/fagro.2023.1330222","url":null,"abstract":"Controlling creeping perennial weeds is challenging throughout all farming systems. The present study distinguished and explored three different methods to control them non-chemically: disturbance with inversion, disturbance without inversion, and competition. Focusing on Cirsium arvense, Elymus repens, and Sonchus arvensis, we conducted a field study (2019–2021) at three northern European sites in Germany, Finland, and Norway. We investigated the effects of the control methods ploughing (inversion disturbance), root cutting (non-inversion disturbance), and cover crops (competition) alone. Root cutting was conducted using a prototype machine developed by “Kverneland”. Eight treatments were tested in factorial designs adapted for each site. Control methods were applied solely and combined. Response variables after treatments were aboveground weed biomass and grain yield of spring cereals. The control method of ploughing was most effective in reducing weed biomass compared to root cutting or cover crops. However, compared to the untreated control, a pronounced additive effect of root cutting and cover crops occurred, reducing weed biomass (−57.5%) similar to ploughing (−66%). Pooled over sites, the response was species-specific, with each species showing a distinct reaction to both control methods. C. arvense was most susceptible to root cutting, followed by E. repens, while S. arvensis showed no susceptibility. Crop yield losses were prevented compared to untreated plots by ploughing (+60.57%) and root cutting (+30%), but not by cover crops. We conclude that the combination of non-inversion disturbance and competition is a promising strategy to reduce the reliance on herbicides or inversion tillage in the management of perennial weeds.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139619976","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 : 2024-01-16DOI: 10.3389/fagro.2023.1330073
Micaela Malaspina, G. Chantre, Marcos Yanniccari
Cover crops (CC) are increasingly used worldwide within integrated weed management scenarios. They are usually established between two commercial crops and are not harvested, grazed, or incorporated into the soil, but remain on the surface during their growth cycle. The aim of this work was to determine the performance of different CC mixtures and their effects on weed suppression in the south-central region of Buenos Aires province, Argentina. Field experiments were carried out in 2019 and 2020 at the CEI Barrow (MDA-INTA, Tres Arroyos), where both binary and ternary CC mixtures were evaluated. Binary mixtures consisted of winter cereals (Avena sativa, Secale cereale) and legumes (Vicia villosa, Vicia sativa) while ternary mixtures were obtained by combining binary mixtures with canola (Brassica napus). Weed emergence counting was performed on a 14- day basis to determine weed total density. Vegetation cover of the CC mixtures as well as biomass production from crops and weeds were estimated. The specific composition of the mixtures showed a greater influence on vegetation cover than on biomass production, which would depend mainly on the prevailing environmental conditions. The type of vetch used, the addition of canola, as well as, the proportion of cereals in the mixture determined the CC effect on weeds. CC were consistently more effective in suppressing weed biomass than seedling emergence density. However, weed seedling suppression by CC was similar to or even greater than the chemical-based control (p<0.0001). The average biomass of weeds in all CC (pooled data) was highly reduced when compared to the weedy control (12 vs 259 g m-2, p<0.001), and similar responses were obtained when compared to the chemical fallow (8 g m-2). The mixture S. cereal+ V. villosa+ canola stood out for presenting the highest values of productivity and vegetation cover and high weed suppression. These results provide support for the choice of CC mixtures in a dry sub-humid area of Argentina, aimed at maximizing interference with weeds and also to demonstrate their benefits in short- and long-term management. Therefore, CC implementation within crop sequences should be considered as a complementary tool contributing to the development of more sustainable management strategies.
覆盖作物（CC）在世界范围内越来越多地被用于杂草综合治理方案中。它们通常种植在两种经济作物之间，不收割、不放牧，也不融入土壤，而是在生长周期中保留在地表。这项工作的目的是确定不同 CC 混合物的性能及其对阿根廷布宜诺斯艾利斯省中南部地区杂草抑制的影响。2019年和2020年，在CEI Barrow（MDA-INTA，Tres Arroyos）进行了田间试验，对二元和三元CC混合物进行了评估。二元混合物由冬季谷物（莜麦、禾谷）和豆科植物（禾本科、荠菜）组成，而三元混合物则是通过将二元混合物与油菜籽（甘蓝）组合而成。对杂草的出苗率进行了为期 14 天的计数，以确定杂草的总密度。对 CC 混合物的植被覆盖率以及作物和杂草的生物量产量进行了估算。混合物的具体成分对植被覆盖率的影响大于对生物量产量的影响，后者主要取决于当时的环境条件。使用的薇菜类型、添加的油菜籽以及混合物中谷物的比例决定了 CC 对杂草的影响。在抑制杂草生物量方面，CC始终比出苗密度更有效。不过，CC 对杂草幼苗的抑制作用与化学防治相似，甚至更大（p<0.0001）。与杂草对照（12 vs 259 g m-2，p<0.001）相比，所有 CC（汇总数据）中杂草的平均生物量都大大减少，与化学休耕（8 g m-2）相比，也取得了类似的效果。S. cereal+ V. villosa+ canola 混合物的生产率和植被覆盖率最高，对杂草的抑制率也很高。这些结果为在阿根廷亚湿润干旱地区选择 CC 混合物提供了支持，其目的是最大限度地干扰杂草，并证明其在短期和长期管理中的益处。因此，在作物序列中实施 CC 应被视为一种补充工具，有助于制定更可持续的管理策略。
{"title":"Effect of cover crops mixtures on weed suppression capacity in a dry sub-humid environment of Argentina","authors":"Micaela Malaspina, G. Chantre, Marcos Yanniccari","doi":"10.3389/fagro.2023.1330073","DOIUrl":"https://doi.org/10.3389/fagro.2023.1330073","url":null,"abstract":"Cover crops (CC) are increasingly used worldwide within integrated weed management scenarios. They are usually established between two commercial crops and are not harvested, grazed, or incorporated into the soil, but remain on the surface during their growth cycle. The aim of this work was to determine the performance of different CC mixtures and their effects on weed suppression in the south-central region of Buenos Aires province, Argentina. Field experiments were carried out in 2019 and 2020 at the CEI Barrow (MDA-INTA, Tres Arroyos), where both binary and ternary CC mixtures were evaluated. Binary mixtures consisted of winter cereals (Avena sativa, Secale cereale) and legumes (Vicia villosa, Vicia sativa) while ternary mixtures were obtained by combining binary mixtures with canola (Brassica napus). Weed emergence counting was performed on a 14- day basis to determine weed total density. Vegetation cover of the CC mixtures as well as biomass production from crops and weeds were estimated. The specific composition of the mixtures showed a greater influence on vegetation cover than on biomass production, which would depend mainly on the prevailing environmental conditions. The type of vetch used, the addition of canola, as well as, the proportion of cereals in the mixture determined the CC effect on weeds. CC were consistently more effective in suppressing weed biomass than seedling emergence density. However, weed seedling suppression by CC was similar to or even greater than the chemical-based control (p<0.0001). The average biomass of weeds in all CC (pooled data) was highly reduced when compared to the weedy control (12 vs 259 g m-2, p<0.001), and similar responses were obtained when compared to the chemical fallow (8 g m-2). The mixture S. cereal+ V. villosa+ canola stood out for presenting the highest values of productivity and vegetation cover and high weed suppression. These results provide support for the choice of CC mixtures in a dry sub-humid area of Argentina, aimed at maximizing interference with weeds and also to demonstrate their benefits in short- and long-term management. Therefore, CC implementation within crop sequences should be considered as a complementary tool contributing to the development of more sustainable management strategies.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139619568","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 : 2024-01-15DOI: 10.3389/fagro.2023.1293555
Andrea-Lorena Garduño-Jiménez, Laura J. Carter
The reuse of wastewater to meet irrigation requirements and slurries, sludges and manures as fertilisers to meet crop nutrient demands inadvertently introduces human and veterinary-use pharmaceuticals into the agro-ecosystem. This review synthesises recent research, which has observed sub-lethal effects, following pharmaceutical uptake by plants. Potential links between pharmaceutical mode of action and observed sub-lethal effects in the plant were then examined. Common receptors and biological pathways across species suggests a clear need to integrate plant cellular biology into our understanding of the impacts of pharmaceuticals on important plant functions and processes. To help prioritise future research efforts an analysis of shared mammalian and plant biochemical pathways was undertaken to identify classes of pharmaceuticals which may present a greater risk to key plant functions. These included sulfonylurea antihyperglycemics, steroids, opiods, antipsychotic phenothiazines and pharmaceuticals targeting several neurotransmitters shared between mammals and plants (including beta-blockers, antihistamines and benzodiazepines). Whilst a number of pharmaceutical induced sub-lethal effects have been observed, this review highlights the clear need to study a wider range of pharmaceuticals on a broader range of plant species, including cover crops and wild plants, under realistic exposure scenarios, to fully understand the wider implications of pharmaceutical exposure in agro-ecosystems. State-of-the art omics-techniques offer great potential to understand the mode of action of pharmaceuticals in plants and elucidate links between the pharmaceutical intended mode of action and observed plant effects. In addition, studies under co-stress from pharmaceutical exposure and other stressors such as increased temperatures, drought or pests are lacking and present an urgent research need in the face of feeding a growing population under the threats of climate change.
{"title":"Insights into mode of action mediated responses following pharmaceutical uptake and accumulation in plants","authors":"Andrea-Lorena Garduño-Jiménez, Laura J. Carter","doi":"10.3389/fagro.2023.1293555","DOIUrl":"https://doi.org/10.3389/fagro.2023.1293555","url":null,"abstract":"The reuse of wastewater to meet irrigation requirements and slurries, sludges and manures as fertilisers to meet crop nutrient demands inadvertently introduces human and veterinary-use pharmaceuticals into the agro-ecosystem. This review synthesises recent research, which has observed sub-lethal effects, following pharmaceutical uptake by plants. Potential links between pharmaceutical mode of action and observed sub-lethal effects in the plant were then examined. Common receptors and biological pathways across species suggests a clear need to integrate plant cellular biology into our understanding of the impacts of pharmaceuticals on important plant functions and processes. To help prioritise future research efforts an analysis of shared mammalian and plant biochemical pathways was undertaken to identify classes of pharmaceuticals which may present a greater risk to key plant functions. These included sulfonylurea antihyperglycemics, steroids, opiods, antipsychotic phenothiazines and pharmaceuticals targeting several neurotransmitters shared between mammals and plants (including beta-blockers, antihistamines and benzodiazepines). Whilst a number of pharmaceutical induced sub-lethal effects have been observed, this review highlights the clear need to study a wider range of pharmaceuticals on a broader range of plant species, including cover crops and wild plants, under realistic exposure scenarios, to fully understand the wider implications of pharmaceutical exposure in agro-ecosystems. State-of-the art omics-techniques offer great potential to understand the mode of action of pharmaceuticals in plants and elucidate links between the pharmaceutical intended mode of action and observed plant effects. In addition, studies under co-stress from pharmaceutical exposure and other stressors such as increased temperatures, drought or pests are lacking and present an urgent research need in the face of feeding a growing population under the threats of climate change.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139622806","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 : 2024-01-15DOI: 10.3389/fagro.2023.1303869
Charles Chigemezu Nwokoro, Donald Kachigamba, Margaret Chiipanthenga, Dominik Klauser, Michael Robinson, Robert Berlin
Whitefly (Bemisia tabaci) is a pest of cassava (Manihot esculenta Crantz) and the vector for two of the crop’s major viral diseases – cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), causing severe economic losses for farmers. In this context, we conducted an on-farm experiment to study the efficiency of a seed treatment technology containing thiamethoxam, fludioxonil, and metalaxyl for rapid multiplication of superior cassava genotypes and early protection of the crop against whitefly at Salima and Nkhotakota, central Malawi in the 2019/2020 and 2020/2021 cropping seasons, respectively.The trials were conducted using a randomized complete block design with four replicates. The effect of the application of the seed treatment on stake germination, whitefly population, CMD and CBSD incidences, and stem and storage root yields of three cassava varieties (Kalawe, Mbundumali, and Sauti) at three stake sizes (8 cm, 16 cm, and 25 cm) was compared with control – a 25 cm stake size of each of the cassava variety without seed treatment. A benefit-cost analysis was conducted to determine the profitability of the seed treatment technology for each stake size under certified and non-certified stem scenarios.Regardless of stake size and variety, plant germination was highest (96% by 16%) and mean whitefly population lowest (adult 0.4 vs. 3.0 plant-1; nymph 1.0 vs. 3.3 plant-1) with seed treatment application than without. Disease incidence measurements showed no significant effect of seed treatment on CBSD control (p = 0.31), but it reduced CMD incidence by 17% vs. 20% in the untreated. Stem and storage root yields across stake size and cassava variety were highest with seed treatment; 489 bundles ha-1 and 10 (DM) Mg ha-1, respectively. Using the 8 cm stake regardless of variety resulted in the highest average benefit-cost ratio for certified (18.3 USD USD-1) and non-certified (7.8 USD USD-1) cassava stem scenarios.We conclude that the application of the seed treatment tested in this study would offer protection to planted stakes, increase their germination, reduce whitefly population, increase stem and storage root yields in areas experiencing whitefly pressure, and result in high economic profits.
{"title":"Effects of seed treatment on cassava stake performance, whitefly population, disease incidence, and yield performance of cassava (Manihot esculenta Crantz) in Malawi","authors":"Charles Chigemezu Nwokoro, Donald Kachigamba, Margaret Chiipanthenga, Dominik Klauser, Michael Robinson, Robert Berlin","doi":"10.3389/fagro.2023.1303869","DOIUrl":"https://doi.org/10.3389/fagro.2023.1303869","url":null,"abstract":"Whitefly (Bemisia tabaci) is a pest of cassava (Manihot esculenta Crantz) and the vector for two of the crop’s major viral diseases – cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), causing severe economic losses for farmers. In this context, we conducted an on-farm experiment to study the efficiency of a seed treatment technology containing thiamethoxam, fludioxonil, and metalaxyl for rapid multiplication of superior cassava genotypes and early protection of the crop against whitefly at Salima and Nkhotakota, central Malawi in the 2019/2020 and 2020/2021 cropping seasons, respectively.The trials were conducted using a randomized complete block design with four replicates. The effect of the application of the seed treatment on stake germination, whitefly population, CMD and CBSD incidences, and stem and storage root yields of three cassava varieties (Kalawe, Mbundumali, and Sauti) at three stake sizes (8 cm, 16 cm, and 25 cm) was compared with control – a 25 cm stake size of each of the cassava variety without seed treatment. A benefit-cost analysis was conducted to determine the profitability of the seed treatment technology for each stake size under certified and non-certified stem scenarios.Regardless of stake size and variety, plant germination was highest (96% by 16%) and mean whitefly population lowest (adult 0.4 vs. 3.0 plant-1; nymph 1.0 vs. 3.3 plant-1) with seed treatment application than without. Disease incidence measurements showed no significant effect of seed treatment on CBSD control (p = 0.31), but it reduced CMD incidence by 17% vs. 20% in the untreated. Stem and storage root yields across stake size and cassava variety were highest with seed treatment; 489 bundles ha-1 and 10 (DM) Mg ha-1, respectively. Using the 8 cm stake regardless of variety resulted in the highest average benefit-cost ratio for certified (18.3 USD USD-1) and non-certified (7.8 USD USD-1) cassava stem scenarios.We conclude that the application of the seed treatment tested in this study would offer protection to planted stakes, increase their germination, reduce whitefly population, increase stem and storage root yields in areas experiencing whitefly pressure, and result in high economic profits.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139530474","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 : 2024-01-11DOI: 10.3389/fagro.2023.1341880
G. Mahajan, B. S. Chauhan
Annual ryegrass (Lolium rigidum Gaudin) is a problematic weed in most of the cropping regions in Australia. Evolved herbicide resistance to multiple modes of action groups, the lack of new herbicidal molecules, and the emergence of late cohorts in winter season crops necessitate the use of existing herbicides in an innovative way to control L. rigidum. Pendimethalin as pre-emergence (PRE) is used for L. rigidum control; however, it is unable to control late cohorts of L. rigidum in winter season crops. Pot studies were conducted from 2019 to 2021 to evaluate the effect of a post-emergence (POST) application of pendimethalin with six doses (0, 220, 440, 880, 1,760, and 3,520 g a.i. ha-1) on L. rigidum control in addition to crop safety in wheat, barley, and sorghum. POST application of pendimethalin was found to be safe for wheat and barley, and the biomass reduction in both crops at varied rates (220 to 3,520 g ha−1) of pendimethalin ranged from 10% to 20%. A dose–response study revealed that the pendimethalin dose required for 50% mortality and growth reduction of L. rigidum was 179 and 144 g ai ha−1, respectively. Pendimethalin at 880 g ai ha−1 completely killed late cohorts of L. rigidum. These results suggest that the POST application of pendimethalin can be used for the effective control of late cohorts of L. rigidum in wheat and barley crops. POST application of pendimethalin suppressed the biomass of sorghum plants compared with the non-treated control treatment, and biomass reduction in sorghum at different pendimethalin doses ranged from 32% to 40%. Results implied that POST applications of pendimethalin in wheat and barley can diversify herbicide programs in managing L. rigidum and may help in delaying the evolution of resistance in this weed.
一年生黑麦草（Lolium rigidum Gaudin）是澳大利亚大部分种植区的问题杂草。由于对多种作用方式的除草剂产生了抗药性，缺乏新的除草剂分子，以及冬季作物出现晚熟品种，因此必须以创新的方式使用现有的除草剂来控制硬叶黑麦草。苄嘧磺隆（Pendimethalin）作为萌芽前除草剂（PRE）可用于控制硬叶鳞茎，但无法控制冬季作物中硬叶鳞茎的后期群落。在2019年至2021年期间进行了盆栽研究，以评估六种剂量（0、220、440、880、1,760和3,520 g a.i. ha-1）的萌芽后（POST）施用戊唑醇对小麦、大麦和高粱中僵菌的控制效果以及作物安全性。研究发现，小麦和大麦在施药后施用戊唑醇是安全的，在施用不同剂量（220 至 3,520 克/公顷-1）的戊唑醇后，两种作物的生物量减少了 10% 至 20%。剂量-反应研究表明，使僵叶蓟马死亡和生长减少 50%所需的戊唑醇剂量分别为 179 和 144 g ai ha-1。880 g ai ha-1 的苯醚甲环唑可完全杀死晚期的僵尾金龟子。这些结果表明，在小麦和大麦作物的后期施用戊唑醇可有效控制僵菌后期群落。与未施药的对照处理相比，施药后施用戊唑醇抑制了高粱植株的生物量，不同剂量的戊唑醇对高粱生物量的抑制率为 32% 至 40%。研究结果表明，在小麦和大麦中施用噻草酮后，可以使除草剂方案多样化，从而管理硬粒禾本科杂草，并有助于延缓该杂草抗药性的演变。
{"title":"Novel use pattern of pendimethalin for annual ryegrass (Lolium rigidum Gaudin) control in wheat and barley","authors":"G. Mahajan, B. S. Chauhan","doi":"10.3389/fagro.2023.1341880","DOIUrl":"https://doi.org/10.3389/fagro.2023.1341880","url":null,"abstract":"Annual ryegrass (Lolium rigidum Gaudin) is a problematic weed in most of the cropping regions in Australia. Evolved herbicide resistance to multiple modes of action groups, the lack of new herbicidal molecules, and the emergence of late cohorts in winter season crops necessitate the use of existing herbicides in an innovative way to control L. rigidum. Pendimethalin as pre-emergence (PRE) is used for L. rigidum control; however, it is unable to control late cohorts of L. rigidum in winter season crops. Pot studies were conducted from 2019 to 2021 to evaluate the effect of a post-emergence (POST) application of pendimethalin with six doses (0, 220, 440, 880, 1,760, and 3,520 g a.i. ha-1) on L. rigidum control in addition to crop safety in wheat, barley, and sorghum. POST application of pendimethalin was found to be safe for wheat and barley, and the biomass reduction in both crops at varied rates (220 to 3,520 g ha−1) of pendimethalin ranged from 10% to 20%. A dose–response study revealed that the pendimethalin dose required for 50% mortality and growth reduction of L. rigidum was 179 and 144 g ai ha−1, respectively. Pendimethalin at 880 g ai ha−1 completely killed late cohorts of L. rigidum. These results suggest that the POST application of pendimethalin can be used for the effective control of late cohorts of L. rigidum in wheat and barley crops. POST application of pendimethalin suppressed the biomass of sorghum plants compared with the non-treated control treatment, and biomass reduction in sorghum at different pendimethalin doses ranged from 32% to 40%. Results implied that POST applications of pendimethalin in wheat and barley can diversify herbicide programs in managing L. rigidum and may help in delaying the evolution of resistance in this weed.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139626124","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 : 2024-01-08DOI: 10.3389/fagro.2023.1274703
O. Fishkis, Joern Strassemeyer, Franz Pöllinger, Christel Anne Roß, Heinz-Josef Koch
The EU Farm to Fork strategy aims to reduce the use of pesticides and associated toxicological risks. However, the risks coming along with currently available alternatives to chemical weed control in sugar beet have not yet been evaluated. Therefore, the aim of this study was to determine the toxicological risks to arthropods, aquatic and soil organisms caused by mechanical-chemical in comparison to conventional chemical weed control in sugar beet.The risk assessment was performed using SYNOPS-GIS, a process-based model calculating the environmental fate of pesticides and the exposure risk to arthropods, aquatic and soil organisms.Overall, broadcast spraying of conventional herbicides caused low to very low toxicological risks in most regions and years in Germany. Nevertheless, there were considerably higher risks to aquatic and soil organisms from conventional broadcast spraying in northern Germany than in other regions of Germany. With conventional herbicides, mechanical-chemical weed control reduced toxicological risks proportionally to the reduction in application amount. In contrast, band spraying of the new herbicide with the active ingredients foramsulfuron and thiencarbazone-methyl caused an aquatic risk as broadcast spraying with conventional herbicides, although the application rate was 120 times lower. This was due to high toxicity of both active ingredients of the new herbicide to water plants.Not only the application amount of herbicides but also environmental toxicity should be included in assessment approaches such as the EU “Harmonized Risk Indicator”.
{"title":"Toxicological risk assessment of mechanical-chemical vs. chemical weed control techniques in sugar beet in Germany using SYNOPS-GIS","authors":"O. Fishkis, Joern Strassemeyer, Franz Pöllinger, Christel Anne Roß, Heinz-Josef Koch","doi":"10.3389/fagro.2023.1274703","DOIUrl":"https://doi.org/10.3389/fagro.2023.1274703","url":null,"abstract":"The EU Farm to Fork strategy aims to reduce the use of pesticides and associated toxicological risks. However, the risks coming along with currently available alternatives to chemical weed control in sugar beet have not yet been evaluated. Therefore, the aim of this study was to determine the toxicological risks to arthropods, aquatic and soil organisms caused by mechanical-chemical in comparison to conventional chemical weed control in sugar beet.The risk assessment was performed using SYNOPS-GIS, a process-based model calculating the environmental fate of pesticides and the exposure risk to arthropods, aquatic and soil organisms.Overall, broadcast spraying of conventional herbicides caused low to very low toxicological risks in most regions and years in Germany. Nevertheless, there were considerably higher risks to aquatic and soil organisms from conventional broadcast spraying in northern Germany than in other regions of Germany. With conventional herbicides, mechanical-chemical weed control reduced toxicological risks proportionally to the reduction in application amount. In contrast, band spraying of the new herbicide with the active ingredients foramsulfuron and thiencarbazone-methyl caused an aquatic risk as broadcast spraying with conventional herbicides, although the application rate was 120 times lower. This was due to high toxicity of both active ingredients of the new herbicide to water plants.Not only the application amount of herbicides but also environmental toxicity should be included in assessment approaches such as the EU “Harmonized Risk Indicator”.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139447502","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 : 2024-01-03DOI: 10.3389/fagro.2023.1300324
Xiangming Xu, R. Minja, E. Kizito, F. Dinssa, G. Deakin, Pamela Nahamya Kabod, Asheri Kalala, Eliciana Kweka, O. Mbwambo, Deusdedith Mbanzibwa, Hamza Msangi, Mildred Julian Nakanwagi, T. Passey, Stuart Sentance, G. Sseremba, E. Stavridou, Gerard J. Bishop
African eggplant (Solanum aethiopicum L.) is one of the most common traditional vegetables in Tanzania and Uganda, but its productivity is severely affected by wilt diseases caused by a number of pathogens. Plant stem and root samples were collected in several fields from many neighboring diseased and healthy plants of the Gilo group in Tanzania and from the Shum group in Uganda to identify putative pathogens causing wilt on African eggplants. Through amplicon sequencing of sampled diseased and healthy tissues, we identified putative causal pathogens for the wilt symptoms. Wilting of S. aethiopicum in Uganda is most likely caused by the bacterial pathogen Ralstonia solanacearum whereas, in Tanzania, wilt is most likely caused by the fungal pathogen Macrophomina phaseolina, infecting roots. Infection of stems by Fusarium solani may also contribute to the wilt symptoms in Tanzania. Further artificial inoculation under controlled conditions confirmed that M. phaseolina can cause typical wilting symptoms on S. aethiopcium genotypes. The discovery of different putative causal agents of wilt in the crop demonstrates the need for site specific etiological analysis of wilt before developing and implementing effective control methods. Further research is needed to confirm the results and develop appropriate management measures against specific wilt pathogens.
{"title":"Amplicon sequencing identified a putative pathogen, Macrophomina phaseolina, causing wilt in African eggplant (Solanum aethiopicum) grown in Tanzania and Uganda","authors":"Xiangming Xu, R. Minja, E. Kizito, F. Dinssa, G. Deakin, Pamela Nahamya Kabod, Asheri Kalala, Eliciana Kweka, O. Mbwambo, Deusdedith Mbanzibwa, Hamza Msangi, Mildred Julian Nakanwagi, T. Passey, Stuart Sentance, G. Sseremba, E. Stavridou, Gerard J. Bishop","doi":"10.3389/fagro.2023.1300324","DOIUrl":"https://doi.org/10.3389/fagro.2023.1300324","url":null,"abstract":"African eggplant (Solanum aethiopicum L.) is one of the most common traditional vegetables in Tanzania and Uganda, but its productivity is severely affected by wilt diseases caused by a number of pathogens. Plant stem and root samples were collected in several fields from many neighboring diseased and healthy plants of the Gilo group in Tanzania and from the Shum group in Uganda to identify putative pathogens causing wilt on African eggplants. Through amplicon sequencing of sampled diseased and healthy tissues, we identified putative causal pathogens for the wilt symptoms. Wilting of S. aethiopicum in Uganda is most likely caused by the bacterial pathogen Ralstonia solanacearum whereas, in Tanzania, wilt is most likely caused by the fungal pathogen Macrophomina phaseolina, infecting roots. Infection of stems by Fusarium solani may also contribute to the wilt symptoms in Tanzania. Further artificial inoculation under controlled conditions confirmed that M. phaseolina can cause typical wilting symptoms on S. aethiopcium genotypes. The discovery of different putative causal agents of wilt in the crop demonstrates the need for site specific etiological analysis of wilt before developing and implementing effective control methods. Further research is needed to confirm the results and develop appropriate management measures against specific wilt pathogens.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139451177","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 : 2023-12-18DOI: 10.3389/fagro.2023.1300553
Xiangming Xu, F. Dinssa, R. Minja, V. Mwaijande, O. Mbwambo, Zainab Mziray, E. Stavridou, Gerard J. Bishop
The African eggplant (Solanum aethiopicum L., Gilo group) is one of the most common traditional vegetables in Tanzania. The yield of the African eggplant in Tanzania is far lower than the potential yield expected, which is due primarily to biotic and abiotic stresses. We conducted experiments at two locations in Tanzania to study whether or not plant growth and the fruit yield of the Gilo group of African eggplant can be significantly improved through transplanting coupled with the inoculation of arbuscular mycorrhizal fungi (AMF) at sowing. Many plants, particularly for the directly sown treatment, died well before harvesting, and, in addition, many surviving plants showed symptoms of wilting. The transplanting of tray seedlings and using AMF inocula at sowing led to an overall significant increase in fruit yield by 30%–40% and 20%–25%, respectively. Increased fruit yield per experimental plot resulted primarily from a greater number of plants that survived and reached the harvesting stage. The exact effect of planting method (i.e., transplanting or direct sowing) and AMF inoculation, however, varied greatly with plant accessions. Further research is needed to understand the cause(s) for plant mortality in order to develop appropriate plant management practices.
{"title":"Effects of transplanting and AMF inoculation on the fruit yield of African eggplants (Solanum aethiopicum and Solanum anguivi) in Tanzania","authors":"Xiangming Xu, F. Dinssa, R. Minja, V. Mwaijande, O. Mbwambo, Zainab Mziray, E. Stavridou, Gerard J. Bishop","doi":"10.3389/fagro.2023.1300553","DOIUrl":"https://doi.org/10.3389/fagro.2023.1300553","url":null,"abstract":"The African eggplant (Solanum aethiopicum L., Gilo group) is one of the most common traditional vegetables in Tanzania. The yield of the African eggplant in Tanzania is far lower than the potential yield expected, which is due primarily to biotic and abiotic stresses. We conducted experiments at two locations in Tanzania to study whether or not plant growth and the fruit yield of the Gilo group of African eggplant can be significantly improved through transplanting coupled with the inoculation of arbuscular mycorrhizal fungi (AMF) at sowing. Many plants, particularly for the directly sown treatment, died well before harvesting, and, in addition, many surviving plants showed symptoms of wilting. The transplanting of tray seedlings and using AMF inocula at sowing led to an overall significant increase in fruit yield by 30%–40% and 20%–25%, respectively. Increased fruit yield per experimental plot resulted primarily from a greater number of plants that survived and reached the harvesting stage. The exact effect of planting method (i.e., transplanting or direct sowing) and AMF inoculation, however, varied greatly with plant accessions. Further research is needed to understand the cause(s) for plant mortality in order to develop appropriate plant management practices.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139175446","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 : 2023-12-15DOI: 10.3389/fagro.2023.1304741
B. Tidemann, K. Harker, Steve Shirtliffe, Christian Willenborg, Eric Johnson, Robert Gulden, N. Lupwayi, T. Turkington, Emma C. Stephens, R. Blackshaw, Charles M. Geddes, Hiroshi Kubota, G. Semach, Alick Mulenga, Cindy Gampe, Larry Michielsen, Patty Reid, Elizabeth Sroka, Jennifer Zuidhof
Although herbicides have been a dominant and effective weed control strategy for decades in Western Canada, herbicide resistance and the lack of new modes of action have resulted in weed management challenges. Integrated weed management strategies have been shown to be successful in controlling certain weed species that are problematic in cropping systems. The objective of this study was to investigate integrated weed management strategies that have been successful on individual species to determine their applicability to a multiple weed species that may coexist in a field. In addition, harvest weed seed control was incorporated into these integrated weed management strategies to determine its impact in western Canadian cropping systems. A 5-year rotational study was conducted from 2016 to 2020 at Beaverlodge, Lacombe, and Lethbridge, AB; Scott and Saskatoon, SK; and Carman, MB, that incorporated integrated weed management strategies such as rotational crop diversity (including winter annuals and perennials), increased seeding rates, crop silaging, chaff collection, and with or without in-crop herbicides. This research confirmed success in managing some species of weeds such as wild oat when increased seeding rates, 2 years of early cut silage barley, and competitive winter cereals were incorporated into a cropping system, even when no in-crop herbicides were applied. However, some weed growth morphologies (e.g., twining weeds) or life cycles (e.g., facultative winter annuals) were not managed successfully with this combination of strategies. Chaff collection provided incremental weed control benefits but did not serve as a replacement for herbicidal weed control. Weed densities had an apparent impact on the success of these integrated weed management strategies, suggesting that the sooner they are adopted, the more likely they are to be successful at maintaining or reducing weed densities. This study not only showed the ability to reduce reliance on herbicides with strategies that can be effective in Western Canada but also highlighted the need for further understanding of different weed species and their responses to integrated weed management strategies, as well as the complexity of managing a weed community with integrated weed management.
尽管几十年来除草剂一直是加拿大西部地区主要且有效的杂草控制策略，但除草剂的抗药性和缺乏新的作用模式导致杂草管理面临挑战。综合杂草管理策略已被证明能成功控制某些在种植系统中造成问题的杂草种类。本研究的目的是调查在单个物种上取得成功的杂草综合管理策略，以确定这些策略是否适用于田间可能共存的多种杂草物种。此外，还将收割杂草种子控制纳入这些综合杂草管理策略，以确定其对加拿大西部耕作系统的影响。从 2016 年到 2020 年，在加拿大 AB 省的 Beaverlodge、Lacombe 和 Lethbridge；SK 省的 Scott 和 Saskatoon；以及 MB 省的 Carman 开展了一项为期 5 年的轮作研究，其中纳入了综合杂草管理策略，如轮作作物多样性（包括冬季一年生和多年生作物）、提高播种率、作物青贮、收集秕谷，以及使用或不使用作物内除草剂。这项研究证实，在增加播种率、种植两年早割青贮大麦和竞争性冬季谷物的种植系统中，即使不施用作物内除草剂，也能成功控制某些杂草种类，如野燕麦。然而，一些杂草的生长形态（如缠绕杂草）或生命周期（如面冬一年生杂草）并不能通过这种策略组合成功控制。收集谷糠可带来控制杂草的增量效益，但不能替代除草剂控制杂草。杂草密度对这些综合杂草管理策略的成功与否有着明显的影响，这表明越早采用这些策略，就越有可能成功保持或降低杂草密度。这项研究不仅显示了在加拿大西部采用有效策略减少对除草剂依赖的能力，还强调了进一步了解不同杂草种类及其对综合杂草管理策略反应的必要性，以及采用综合杂草管理策略管理杂草群落的复杂性。
{"title":"Using integrated weed management systems to manage herbicide-resistant weeds in the Canadian Prairies","authors":"B. Tidemann, K. Harker, Steve Shirtliffe, Christian Willenborg, Eric Johnson, Robert Gulden, N. Lupwayi, T. Turkington, Emma C. Stephens, R. Blackshaw, Charles M. Geddes, Hiroshi Kubota, G. Semach, Alick Mulenga, Cindy Gampe, Larry Michielsen, Patty Reid, Elizabeth Sroka, Jennifer Zuidhof","doi":"10.3389/fagro.2023.1304741","DOIUrl":"https://doi.org/10.3389/fagro.2023.1304741","url":null,"abstract":"Although herbicides have been a dominant and effective weed control strategy for decades in Western Canada, herbicide resistance and the lack of new modes of action have resulted in weed management challenges. Integrated weed management strategies have been shown to be successful in controlling certain weed species that are problematic in cropping systems. The objective of this study was to investigate integrated weed management strategies that have been successful on individual species to determine their applicability to a multiple weed species that may coexist in a field. In addition, harvest weed seed control was incorporated into these integrated weed management strategies to determine its impact in western Canadian cropping systems. A 5-year rotational study was conducted from 2016 to 2020 at Beaverlodge, Lacombe, and Lethbridge, AB; Scott and Saskatoon, SK; and Carman, MB, that incorporated integrated weed management strategies such as rotational crop diversity (including winter annuals and perennials), increased seeding rates, crop silaging, chaff collection, and with or without in-crop herbicides. This research confirmed success in managing some species of weeds such as wild oat when increased seeding rates, 2 years of early cut silage barley, and competitive winter cereals were incorporated into a cropping system, even when no in-crop herbicides were applied. However, some weed growth morphologies (e.g., twining weeds) or life cycles (e.g., facultative winter annuals) were not managed successfully with this combination of strategies. Chaff collection provided incremental weed control benefits but did not serve as a replacement for herbicidal weed control. Weed densities had an apparent impact on the success of these integrated weed management strategies, suggesting that the sooner they are adopted, the more likely they are to be successful at maintaining or reducing weed densities. This study not only showed the ability to reduce reliance on herbicides with strategies that can be effective in Western Canada but also highlighted the need for further understanding of different weed species and their responses to integrated weed management strategies, as well as the complexity of managing a weed community with integrated weed management.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138995922","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 : 2023-12-12DOI: 10.3389/fagro.2023.1300545
Abdul A. Jalloh, A. Yusuf, F. Khamis, Sevgan Subramanian, D. Mutyambai
Plant-soil feedback can influence aboveground interactions between plants and herbivores by affecting plant chemistry. Such interactions can be utilized in pest management. However, cropping systems such as maize-legume intercropping (MLI) can influence these interactions which is not well understood. In this study, we explored effects of MLI systems on soil physico-chemical properties, maize growth, larval feeding and development of fall armyworm (Spodoptera frugiperda). We used sterile soil and soil conditioned by different MLI and maize-monoculture cropping systems to explore these interactions. Soil samples that included soil conditioned by different MLI and maize-monoculture cropping systems were collected from smallholder farmer fields in eastern Kenya, where different MLI and maize-monoculture cropping systems were being practiced. These soil samples were compared with sterile soils for physico-chemical properties using black oxidation and Walkley methods. Three-weeks-old maize plants grown in the different soil treatments in the greenhouse were used for larval feeding and development assays. Neonate S. frugiperda larvae were allowed to feed on maize leaf discs for 24 hours and another set of plants were inoculated with the neonates for 15 days and the larval survival and development monitored. Soil obtained from different maize-edible legume intercropping systems had a higher pH, electrical conductivity, nitrogen, organic carbon, potassium, phosphorus, calcium, magnesium, exchangeable acidity, copper, clay and silt compared to maize-monoculture and sterile soil. Maize plants grown in MLI soil had better growth parameters compared to those in maize-monoculture and sterile soils. A high correlation was found between pH and plant biomass, while no significant correlation with other physico-chemical properties was noted. There were significant differences in larval feeding by S. frugiperda neonates when exposed to constitutive and induced maize leaf discs with more leaf tissue fed on maize grown in maize-monoculture and sterile soil. When allowed to feed for 15 days, S. frugiperda larval weight and length were significantly lower on maize plants grown in soils conditioned by MLI than those grown in soil conditioned by maize-monoculture and sterile soils. Findings from this study show how conditioning soil by MLI systems improve soil health, maize growth and reduces S. spodoptera larval feeding and development.
{"title":"Soil legacies in maize-edible legume intercropping alter maize growth and reduce Spodoptera frugiperda larval feeding","authors":"Abdul A. Jalloh, A. Yusuf, F. Khamis, Sevgan Subramanian, D. Mutyambai","doi":"10.3389/fagro.2023.1300545","DOIUrl":"https://doi.org/10.3389/fagro.2023.1300545","url":null,"abstract":"Plant-soil feedback can influence aboveground interactions between plants and herbivores by affecting plant chemistry. Such interactions can be utilized in pest management. However, cropping systems such as maize-legume intercropping (MLI) can influence these interactions which is not well understood. In this study, we explored effects of MLI systems on soil physico-chemical properties, maize growth, larval feeding and development of fall armyworm (Spodoptera frugiperda). We used sterile soil and soil conditioned by different MLI and maize-monoculture cropping systems to explore these interactions. Soil samples that included soil conditioned by different MLI and maize-monoculture cropping systems were collected from smallholder farmer fields in eastern Kenya, where different MLI and maize-monoculture cropping systems were being practiced. These soil samples were compared with sterile soils for physico-chemical properties using black oxidation and Walkley methods. Three-weeks-old maize plants grown in the different soil treatments in the greenhouse were used for larval feeding and development assays. Neonate S. frugiperda larvae were allowed to feed on maize leaf discs for 24 hours and another set of plants were inoculated with the neonates for 15 days and the larval survival and development monitored. Soil obtained from different maize-edible legume intercropping systems had a higher pH, electrical conductivity, nitrogen, organic carbon, potassium, phosphorus, calcium, magnesium, exchangeable acidity, copper, clay and silt compared to maize-monoculture and sterile soil. Maize plants grown in MLI soil had better growth parameters compared to those in maize-monoculture and sterile soils. A high correlation was found between pH and plant biomass, while no significant correlation with other physico-chemical properties was noted. There were significant differences in larval feeding by S. frugiperda neonates when exposed to constitutive and induced maize leaf discs with more leaf tissue fed on maize grown in maize-monoculture and sterile soil. When allowed to feed for 15 days, S. frugiperda larval weight and length were significantly lower on maize plants grown in soils conditioned by MLI than those grown in soil conditioned by maize-monoculture and sterile soils. Findings from this study show how conditioning soil by MLI systems improve soil health, maize growth and reduces S. spodoptera larval feeding and development.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139009880","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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