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1.
Ecol Appl ; 34(7): e3029, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39256977

RESUMO

Knowledge of how agricultural management interacts with weed seed banks and emergent weed communities is crucial for proactive weed management. Though studies have detailed how differences in disturbance and nutrient applications between organic and conventional herbicide-based systems affect weed communities, few have focused on these same factors in contrasting organic systems. This study assessed the seed banks and emergent weed communities from the most recent crop rotation cycle (2017-2022) of a long-term experiment, which compared four organic grain and forage cropping systems differing in nutrient inputs and soil disturbance. The high fertility (HF) system received high-rate nutrient applications, low fertility (LF) received low-rate applications, enhanced weed management (EWM) focused on weed control through frequent soil disturbance, and reduced tillage (RT) prioritized soil health with less intense or frequent soil disturbance. Soil samples for greenhouse germination assays were collected at the beginning (2017) and end (2022) of the rotation to explore how these four systems influenced seed bank dynamics over time. Weed community biomass was also sampled in each crop during this time. Treatment effects on weed abundance, taxonomic diversity, and community-weighted means and functional dispersion of weed traits were analyzed with generalized mixed-effect models. The RT system had the highest weed seed bank taxonomic diversity, and EWM had the lowest. RT and LF had higher functional dispersion of traits than HF in the seed bank. Weed seed bank communities in HF and RT were characterized by short, small-seeded, and early germinating weed species. However, seed banks were also labile: Differences between systems in seed density and all other mean trait values were dependent on the crop, which preceded seed bank sampling. Likewise, differences among emergent weed communities in the four systems depended on an interaction between crop species and their planting year. Results suggest that resource availability and intensity of disturbance act as weed community assembly filters in organic cropping systems. Organic growers seeking to design systems that balance weed management and production goals can use relatively low soil disturbance and nutrient application to increase weed community taxonomic or functional diversity without necessarily increasing weed biomass or seed bank density.


Assuntos
Plantas Daninhas , Controle de Plantas Daninhas , Plantas Daninhas/fisiologia , Controle de Plantas Daninhas/métodos , Solo/química , Biodiversidade , Agricultura/métodos , Agricultura Orgânica/métodos , Produtos Agrícolas , Banco de Sementes , Fertilizantes
2.
Environ Manage ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294479

RESUMO

Dense beds of water plants can be perceived as nuisance, but this perception, however, may not be similar for different user categories, and this may affect their willingness-to-pay (WTP) for plant removal. A questionnaire survey was used to test this for residents and visitors and find underlying socio-cultural or economic drivers. We studied five cases where nuisance water plant growth is managed: the rivers Otra (Norway) and Spree (Germany), and the lakes Kemnade (Germany), Grand-Lieu (France), and Hartbeespoort Dam (South Africa). We used a different payment vehicle for residents (annual household tax) and visitors (tourist tax). The survey included questions on days spent on specific types of activity per year, the importance attached to different functions and activities, overall environmental attitude, perception of the plants, socio-demographic respondent characteristics and WTP for increased plant removal. We observed no increase in WTP for increased removal in most sites. The two most important drivers of variation in current WTP were income, and whether respondents were engaged in boating and angling and thus perceived the plants negatively. Variation in WTP among sites was considerable, and mainly related to the mixture of activities among respondents. Differences between residents and visitors were less important than those among sites. Our observations bear importance for water management: information on differences in experienced nuisance among user categories and the frequency of use by these categories is useful as guidance for the design and implementation of any plant removal plan.

3.
Pest Manag Sci ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305079

RESUMO

BACKGROUND: Leersia japonica (Makino) Honda is a perennial weed and currently identified as a new dominant weed species in rice fields in many countries, including China. Here, we studied the biological characteristics combined with nonchemical management of L. japonica to develop a proper control strategy of this weed. RESULTS: The results showed that 33/28 °C in a 12 h:12 h, light:dark photoperiod were the most suitable growth conditions for seedling regeneration. Salt (NaCl) inhibits the regeneration of seedlings totally at a concentration of 51.3 mm. Seedlings of L. japonica could regenerate in a wide range of pH environments (from 3.50 to 9.50), endowing L. japonica with strong pH adaptability. Osmotic stress also inhibits the regeneration of seedlings totally at -0.13 MPa. A long dehydration time inhibits the regeneration of seedlings; no seedlings could be regenerated for 15 h. With low soil moisture content (33.3% and 50%), the regeneration rate and aboveground fresh weight (FW) were significantly lower than these with high soil moisture content (66.7% and 100%). Stem segments buried in the surface (0 cm) of soil could produce seedlings with the highest regeneration rate (37.5%) and seedling aboveground FW (0.64 g). As the soil depth increased, the regeneration rate and aboveground FW decreased significantly and no seedlings could be regenerated beyond 6.9 cm. CONCLUSION: Based on these biological characteristics of L. japonica, creating an environment that is not conducive to regeneration combined with an appropriated tillage system could effectively reduce its occurrence. © 2024 Society of Chemical Industry.

4.
Front Plant Sci ; 15: 1396568, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39228840

RESUMO

Precision weed management (PWM), driven by machine vision and deep learning (DL) advancements, not only enhances agricultural product quality and optimizes crop yield but also provides a sustainable alternative to herbicide use. However, existing DL-based algorithms on weed detection are mainly developed based on supervised learning approaches, typically demanding large-scale datasets with manual-labeled annotations, which can be time-consuming and labor-intensive. As such, label-efficient learning methods, especially semi-supervised learning, have gained increased attention in the broader domain of computer vision and have demonstrated promising performance. These methods aim to utilize a small number of labeled data samples along with a great number of unlabeled samples to develop high-performing models comparable to the supervised learning counterpart trained on a large amount of labeled data samples. In this study, we assess the effectiveness of a semi-supervised learning framework for multi-class weed detection, employing two well-known object detection frameworks, namely FCOS (Fully Convolutional One-Stage Object Detection) and Faster-RCNN (Faster Region-based Convolutional Networks). Specifically, we evaluate a generalized student-teacher framework with an improved pseudo-label generation module to produce reliable pseudo-labels for the unlabeled data. To enhance generalization, an ensemble student network is employed to facilitate the training process. Experimental results show that the proposed approach is able to achieve approximately 76% and 96% detection accuracy as the supervised methods with only 10% of labeled data in CottonWeedDet3 and CottonWeedDet12, respectively. We offer access to the source code (https://github.com/JiajiaLi04/SemiWeeds), contributing a valuable resource for ongoing semi-supervised learning research in weed detection and beyond.

5.
J Agric Food Chem ; 72(33): 18378-18390, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39109514

RESUMO

Resistant weeds severely threaten crop yields as they compete with crops for resources required for survival. Trifludimoxazin, a protoporphyrinogen IX oxidase (PPO) inhibitor, can effectively control resistant weeds. However, its crop safety record is unsatisfactory. Consequently, a scaffold-hopping strategy is employed in this study to develop a series of new triazinone derivatives featuring an amide structure. Most compounds depicted excellent herbicidal activity across a broad spectrum at 37.5-150 g ai/ha, among which (R)-I-5 was equivalent to flumioxazin. (R)-I-5 demonstrated significant crop tolerance to rice and wheat, even at 150 g ai/ha. (R)-I-5 exhibited superior pharmacokinetic features compared to flumioxazin and trifludimoxazin. This was depicted by the absorption, distribution, metabolism, excretion, and toxicity predictions. Notably, proteomics-based analysis was applied for the first time to investigate variations among plant proteins before and after herbicide application, shedding light on the conservative and divergent roles of PPO.


Assuntos
Amidas , Inibidores Enzimáticos , Herbicidas , Plantas Daninhas , Proteômica , Protoporfirinogênio Oxidase , Triazinas , Protoporfirinogênio Oxidase/antagonistas & inibidores , Protoporfirinogênio Oxidase/metabolismo , Protoporfirinogênio Oxidase/química , Herbicidas/química , Herbicidas/farmacologia , Herbicidas/síntese química , Plantas Daninhas/efeitos dos fármacos , Triazinas/química , Triazinas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Amidas/química , Amidas/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/metabolismo , Desenho de Fármacos , Relação Estrutura-Atividade , Triticum/química , Oryza/química , Oryza/metabolismo , Estrutura Molecular
6.
Sci Rep ; 14(1): 18877, 2024 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143153

RESUMO

This study evaluated the impact of differential sowing windows and improved weed management strategies on weed dynamics, productivity, and economic viability of direct drum seeded rice (Oryza sativa L.) in the temperate agro-ecosystem of Kashmir. A two-year field experiment was conducted utilizing a split-plot design with two sowing dates (May 10 and June 3) as main plots and six weed management practices as sub-plots. The earlier sowing date (May 10) resulted in significantly enhanced leaf area index, crop growth rate, relative growth rate, net assimilation rate, and grain and straw yields compared to the later sowing (June 3). Among weed management treatments, four mechanized conoweedings (equivalent to weed-free conditions) and sequential application of bensulfuron methyl + pretilachlor (60 and 600 g a.i. ha-1) as pre-emergence followed by 2,4-D (0.75 kg a.i. ha-1) as post-emergence demonstrated superior efficacy in weed suppression and augmentation of crop growth parameters and yield attributes. These treatments also exhibited the lowest weed index and highest benefit-cost ratio. The May 10 sowing, coupled with efficacious weed control measures, significantly reduced weed density and biomass while concomitantly improving nutrient uptake and economic returns. The results indicate that adopting a May 10 sowing date for direct seeded rice, in conjunction with either four conoweedings or the aforementioned sequential herbicide application, can optimize agronomic productivity and economic profitability under the temperate conditions of Kashmir. The study aided in choosing the best sowing window and efficient weed management strategy for attaining higher productivity and profitability of direct seeded rice in temperate conditions.


Assuntos
Oryza , Plantas Daninhas , Controle de Plantas Daninhas , Oryza/crescimento & desenvolvimento , Controle de Plantas Daninhas/métodos , Plantas Daninhas/crescimento & desenvolvimento , Herbicidas/farmacologia , Agricultura/métodos , Agricultura/economia , Produtos Agrícolas/crescimento & desenvolvimento , Compostos de Fenilureia/farmacologia , Produção Agrícola/métodos , Produção Agrícola/economia , Acetanilidas , Compostos de Sulfonilureia
7.
Plants (Basel) ; 13(16)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39204685

RESUMO

The growing interest in safeguarding agroecosystem biodiversity has led to interest in studying ecological interactions among the various organisms present within the agroecosystem. Indeed, mutualisms between weeds and pollinators are of crucial importance as they influence the respective survival dynamics. In this review, the mutualistic role of flower visitors and the possible (often predominant) abiotic alternatives to insect pollination (self- and wind-pollination) are investigated. Mutualistic relations are discussed in terms of reward (pollen and/or nectar) and attractiveness (color, shape, scent, nectar quality and quantity), analyzing whether and to what extent typical weeds are linked to pollinators by rigid (specialization) or flexible (generalization) mutualistic relations. The entomofauna involved is composed mainly of solitary and social bees, bumblebees, Diptera, and Lepidoptera. While some of these pollinators are polylectic, others are oligolectic, depending on the shape of their mouthparts, which can be suited to explore the flower corollas as function of their depths. Consequently, the persistence dynamics of weed species show more successful survival in plants that are basically (occasional insect pollination) or totally (self and/or wind pollination) unspecialized in mutualistic relations. However, even weed species with typical abiotic pollination are at times visited during periods such as late summer, in which plants with more abundant rewards are insufficiently present or completely absent. Many typically insect-pollinated weeds can represent a valid indicator of the ecological sustainability of crop management techniques, as their survival dynamics are closely dependent on the biodiversity of the surrounding entomofauna. In particular, the presence of plant communities of species pollinated above all by butterflies (e.g., several Caryophyllaceae) gives evidence to the ecological compatibility of the previous agronomic management, in the sense that butterflies require certain weed species for oviposition and subsequent larva rearing and, therefore, provide further evidence of plant biodiversity in the environment.

8.
Pest Manag Sci ; 80(11): 5843-5851, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39007446

RESUMO

BACKGROUND: A 4-year experiment evaluated the effects of different integrated weed management (IWM) programs on the evolution of a Echinochloa crus-galli population resistant to acetolactate synthase (ALS) inhibitors in a maize cropping system. The programs included the continued use of ALS inhibitors, mixing them with alternative herbicides, or without ALS-inhibitors, in all cases under maize monocrop or a biennial crop rotation. RESULTS: IWM programs that relied solely on non-ALS-inhibitors usually achieved high control levels across years (> 90%). Additionally, Trp574Leu-resistant plants became prevalent (> 90%) in programs only using ALS inhibitors, while in the rest the frequency of susceptible plants did not substantially decrease below 40%. Regarding the other monitored grass weeds, Digitaria sanguinalis and Panicum dichotomiflorum were effectively controlled in programs using ALS-inhibitors without soybean rotation or in programs without ALS-inhibitors altogether, excepting the program relying on an 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitor under maize monocrop for the latter species (0%). CONCLUSION: At the end of the experiment, the only IWM programs that reduced infestation levels were the one without ALS-inhibitors under soybean rotation, and the one with standard pre-emergence treatments. These findings highlight the effectiveness of crop rotation and alternative herbicides both pre- or post-emergence in controlling E. crus-galli. ALS-inhibitors, while challenged by resistance in E. crus-galli, remain valuable tools for managing other grass weed species in maize. It is crucial to adapt IWM strategies for herbicide-resistant E. crus-galli and other grass weed populations to mitigate the further evolution of resistance. © 2024 Corteva Agriscience. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Acetolactato Sintase , Echinochloa , Resistência a Herbicidas , Herbicidas , Plantas Daninhas , Controle de Plantas Daninhas , Zea mays , Echinochloa/efeitos dos fármacos , Echinochloa/genética , Zea mays/crescimento & desenvolvimento , Herbicidas/farmacologia , Controle de Plantas Daninhas/métodos , Plantas Daninhas/efeitos dos fármacos , Acetolactato Sintase/antagonistas & inibidores , Acetolactato Sintase/metabolismo , Agricultura/métodos
9.
Front Plant Sci ; 15: 1395393, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39070910

RESUMO

While intensive control of weed populations plays a central role in current agriculture, numerous studies highlight the multifaceted contribution of weeds to the functionality and resilience of agroecosystems. Recent research indicates that increased evenness within weed communities may mitigate yield losses in contrast to communities characterized by lower diversity, since weed species that strongly affect crop yields, also dominate weed communities, with a concurrent reduction of evenness. If confirmed, this observation would suggest a paradigm shift in weed management towards promoting higher community diversity. To validate whether the evenness of weed communities is indeed linked to higher crop productivity, we conducted two field experiments: one analyzing the effects of a natural weed community in an intercrop of faba bean and oat, and the other analyzing the effects of artificially created weed communities, together with the individual sown weed species, in faba bean, oats and an intercrop of both crops. The evenness of the weed communities ranged from 0.2 to 0.9 in the natural weed community, from 0.2 to 0.7 in faba bean, from 0 to 0.8 in the intercrop and from 0.3 to 0.9 in oats. Neither the natural nor the artificial weed community showed significant effects of evenness on crop grain yield or crop biomass. The results of this study do not validate a positive relationship of crop productivity and weed evenness, possibly due to low weed pressure and the absence of competitive effects but suggest that also less diverse weed communities may be maintained without suffering yield losses. This is expected to have far reaching implications, since not only diverse weed communities, but also higher abundances of few weed species may contribute to ecosystem functions and may support faunal diversity associated with weeds.

10.
Heliyon ; 10(13): e33294, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39027551

RESUMO

The objective of this study was to evaluate maize production and the economic profitability of weed management techniques. Field trials were conducted at the Kasapa farm during the 2021/22 growing seasons using a split-plot design with three repetitions. The main factor was the herbicides applied in pre-emergence alone (2L ha-1: acetochlor, bentazon, imazethapyr and 60 g ha-1 chlorimuron-ethyl), then mixed (1L ha-1: acetochlor plus bentazon plus imazethapyr plus 30g ha-1chlorimuron-ethyl), manual hoeing (3-5WAS) including the non-weeding. The secondary factor: maize varieties (GV672A, GV673A, GV664A and Sam4vita). The highest maize dry grain yield (7.66 t ha-1) was associated with imazethapyr, while those of acetochlor and chlorimuron-ethyl (6.86 and 6.92 t ha-1) compared to manual hoeing (7.62 t ha-1, respectively) were low, but much higher than no weeding (1.21 t ha-1). The yields of varieties GV672A and GV664A were higher (6.87 and 6.77 t ha-1), compared to Sam4vita (5.64 t ha-1). The total dry weight of weeds was negatively correlated with all crop parameters, with its maximum value (127.56 g m-2) characterizing non-weeding, and the minimum for manual hoeing (18.83 g m-2). The Ratio Cost Value showed that all treatments were profitable: imazethapyr > bentazon > chlorimuron-ethyl > combination > acetochlor > manual hoeing. However, imazethapyr was economically more profitable and could replace manual hoeing when the field to be weeded increases and labor is scarce.

11.
Plant Pathol J ; 40(3): 310-321, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38835302

RESUMO

Tomato yellow leaf curl virus (TYLCV) and tomato spotted wilt virus (TSWV) are well-known examples of the begomovirus and orthotospovirus genera, respectively. These viruses cause significant economic damage to tomato crops worldwide. Weeds play an important role in the ongoing presence and spread of several plant viruses, such as TYLCV and TSWV, and are recognized as reservoirs for these infections. This work applies a comprehensive approach, encompassing field surveys and molecular techniques, to acquire an in-depth understanding of the interactions between viruses and their weed hosts. A total of 60 tomato samples exhibiting typical symptoms of TYLCV and TSWV were collected from a tomato greenhouse farm in Nonsan, South Korea. In addition, 130 samples of 16 different weed species in the immediate surroundings of the greenhouse were collected for viral detection. PCR and reverse transcription-PCR methodologies and specific primers for TYLCV and TSWV were used, which showed that 15 tomato samples were coinfected by both viruses. Interestingly, both viruses were also detected in perennial weeds, such as Rumex crispus, which highlights their function as viral reservoirs. Our study provides significant insights into the co-occurrence of TYLCV and TSWV in weed reservoirs, and their subsequent transmission under tomato greenhouse conditions. This project builds long-term strategies for integrated pest management to prevent and manage simultaneous virus outbreaks, known as twindemics, in agricultural systems.

12.
Front Plant Sci ; 15: 1375164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855471

RESUMO

The massive use of herbicides since the 1950s has resulted in increasing problems with herbicideresistant weeds and pollution of the environment, including food, feed, and water. These side effects have resulted in political pressures to reduce herbicide application. The European Commission aims to reduce the use and risk of chemicals and more hazardous pesticides in the EU. Therefore, new weed control methods are in demand. Laser weeding might be an alternative to replace or supplement herbicides and other weed control methods in an Integrated Weed Management (IPM) strategy. This work aimed to investigate how increasing laser energy affected common weeds when the apical meristem was exposed to irradiation at the early stages of development. A 50 W thulium-doped fibre laser with a diameter of 2 mm and a wavelength of 2 µm was used. The highest efficacy of laser irradiation was achieved when the grass weed (Alopecurus myosuroides) had one leaf and the dicot species were at the cotyledon stage. There was a large difference between the species' susceptibility to irradiation probably caused by differences in morphology and growth habit. At the 4-leaf stage, most of the species regrew after irradiation. Laser weeding may be a solution to replace or supplement other weed control methods in some crops, but in general the weeds must be irradiated when they are at the cotyledon to 2-leaf stage to avoid regrowth.

13.
Sci Rep ; 14(1): 11173, 2024 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750179

RESUMO

Laser weeding may contribute to less dependency on herbicides and soil tillage. Several research and commercial projects are underway to develop robots equipped with lasers to control weeds. Artificial intelligence can be used to locate and identify weed plants, and mirrors can be used to direct a laser beam towards the target to kill it with heat. Unlike chemical and mechanical weed control, laser weeding only exposes a tiny part of the field for treatment. Laser weeding leaves behind only ashes from the burned plants and does not disturb the soil. Therefore, it is an eco-friendly method to control weed seedlings. However, perennial weeds regrow from the belowground parts after the laser destroys the aerial shoots. Depletion of the belowground parts for resources might be possible if the laser continuously kills new shoots, but it may require many laser treatments. We studied how laser could be used to destroy the widespread and aggressive perennial weed Elymus repens after the rhizomes were cut into fragments. Plants were killed with even small dosages of laser energy and stopped regrowing. Generally, the highest efficacy was achieved when the plants from small rhizomes were treated at the 3-leaf stage.


Assuntos
Lasers , Controle de Plantas Daninhas , Controle de Plantas Daninhas/métodos , Elymus/crescimento & desenvolvimento , Plantas Daninhas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação
14.
Sci Total Environ ; 933: 173269, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38754518

RESUMO

Climate change will impact the carrot seed industry globally. One adaptation strategy to limit climatic impacts on the production of commercial carrot seeds is geographical shift. However, production must be shifted to climate-optimal places that are free from weeds such as wild carrots to avoid genetic contamination via hybridization. The process of gene flow between wild and cultivated carrots is critical to enable management of wild carrots in the face of climate change. This review systematically assesses the resilience of wild carrots to climate change and their impact on commercial carrot seed production globally with a focus on New Zealand as a major carrot seed producer. The literature was critically analyzed based on three specific components: i) resilience of wild carrots to climate change ii) genetic contamination between wild and cultivated carrots, and iii) management of wild carrots. The majority of the articles were published between 2013 and 2023 (64.71 %), and most of these studies were conducted in Europe (37.26 %) and North America (27.45 %). Country-wise analysis demonstrated that the majority of the studies were carried out in the United States (23.53 %) and the Netherlands (11.77 %). There was limited research conducted in other regions, especially in Oceania (1.96 %). Spatial distribution analysis revealed that the wild carrot was reported in around 100 countries. In New Zealand the North Island has a higher incidence of wild carrot invasion than the South Island. The findings indicated that the wild carrot is becoming more adaptable to climate change, compromising the genetic purity of cultivated carrots due to pollen flow from wild to cultivated carrots. Therefore, ongoing research will be helpful in developing sustainable weed management strategies and predicting potential geographical invasiveness. This study provides a guide for scientists, policymakers, industrialists, and farmers to control wild carrots and produce genetically pure commercial seeds amid climate change.


Assuntos
Mudança Climática , Daucus carota , Fluxo Gênico , Daucus carota/genética , Nova Zelândia , Pólen , Sementes
15.
Heliyon ; 10(10): e31554, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38818181

RESUMO

In recent years, an increase in weed infestation, which is adversely affecting crop growth and productivity has been a major challenge facing the farmers of South Asia. The adoption of a permanent bed in combination with residue retention-based crop management practices may reduce weed abundance and increase crop productivity. In a two-year field study, we evaluated the responses of different organic weed management practices with contrasting tillage and residue (R) management strategies to weed dynamics and crop productivity under rice-maize rotation. The main plot treatments consisted of zero-tillage direct seeded rice and zero-tillage maize (ZTR fb ZTM); ZTDSR and maize both on permanent raised beds with residue (PBDSR + R fb PBDSM + R); PBDSR and PBM without residue (PBDSR-R fb PBDSM-R) and conventional tillage puddled transplanted rice and conventional tillage maize (CTR fb CTM). The subplots comprised unweeded control; vermicompost mulch; P- enriched vermicompost mulch; live mulch with Sesbania spp. in rice and Pisum sativum in maize and weed-free. Total weed density and biomass in rice and maize at 30 days after sowing (DAS) were minimum for PBDSR + R fb PBDSM + R compared to remaining tillage and residue management practices in both years. Apart from weed-free treatment, the highest weed control index was found with live mulch. Yield of rice and maize were found higher in permanent beds along with residue retention-based practices. In rice, the weed-free treatment showed the highest grain yield and live mulch reported 9.8 and 6.8 % higher grain yield than vermicompost mulch and P-enriched vermicompost mulch respectively. Our study shows that conservation agriculture practices under rice-maize rotation is one of the ways to reduce weed density and improve crop productivity in South Asia and other similar agro-ecologies.

16.
Plant Sci ; 345: 112104, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38685454

RESUMO

Weeds are the primary biotic constraint affecting sesame growth and production. Here, we applied EMS mutagenesis to an elite sesame cultivar and discovered a novel point mutation in the sesame SiALS gene conferring resistance to imidazolinone, a group of acetolactate-synthase (ALS)-inhibitors. The mutant line exhibited high resistance to imazamox, an ALS-inhibitor, with hybrid plants displaying an intermediate response. Field-based validation confirmed the mutant line's substantial resistance, leading to a significantly higher yield under imazamox treatment. Under pre-emergence application of imazapic, the mutant plants sustained growth, whereas wild-type and weed were effectively controlled. Field trials using s-metolachlor and imazapic combined resulted in weed-free plots compared to untreated controls. Consequently, this treatment showed a significantly greater yield (2280 vs. 880 Kg ha-1) than the commercial practice (s-metolachlor). Overall, our study unveils the potential of utilizing this point mutation in sesame breeding programs, offering new opportunities for integrated weed management strategies for sesame cultivation. Developing herbicide-resistant crop plants holds promise for supporting sustainable production and addressing the challenges of weed infestations in sesame farming.


Assuntos
Resistência a Herbicidas , Herbicidas , Sesamum , Controle de Plantas Daninhas , Controle de Plantas Daninhas/métodos , Resistência a Herbicidas/genética , Sesamum/genética , Sesamum/crescimento & desenvolvimento , Herbicidas/farmacologia , Acetolactato Sintase/genética , Plantas Daninhas/genética , Plantas Daninhas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mutação , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento
17.
Environ Res ; 252(Pt 1): 118839, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38570131

RESUMO

Weeds pose multifaceted challenges in rice cultivation, leading to substantial economic losses through reduced yield and poor grain quality. Harnessing the natural genetic diversity in germplasm collections becomes crucial for identifying novel herbicide resistance loci in crops. A comprehensive analysis was conducted on 475 rice accessions from the KRICE depository, assessing their response to TFT (tefuryltrione) and probing the underlying HIS1 (HPPD INHIBITOR SENSITIVE 1) genotypic variations. The HIS1 gene, responsible for detoxifying benzobicyclon (BBC) and imparting broad-spectrum herbicide resistance, holds significant promise in rice breeding. This study explores the genetic landscape of HIS1 within Korean rice collection (KRICE), aiming to unveil genetic variations, haplotype diversity, and evolutionary relationships across diverse rice ecotypes. The indica ecotype showed the highest nucleotide diversity, while the wild and temperate japonica groups exhibited low diversity, hinting at selective sweeps and possible population expansion. Negative Tajima's D values in temperate japonica and wild groups indicate an excess of low-frequency mutations, potentially resulting from selective sweeps. In contrast, with positive Tajima's D values, admixture, indica, and aus groups suggest balancing selection. Furthermore, haplotype analysis uncovered 42 distinct haplotypes within KRICE, with four shared haplotypes between cultivated and wild accessions, four specific to cultivated accessions, and 34 specific to wild types. Phenotypic assessments of these haplotypes revealed that three haplotypes, viz., Hap_1 (predominant in japonica), Hap_2 (predominant in indica), and Hap_3 (specific to indica), displayed significant differences from aus-specific Hap_4 and indica-specific Hap_5. This study offers insights into genetic diversity, selective pressures, and ecotype-specific responses, ultimately paving the way for developing HPPD-inhibiting herbicide-resistant rice cultivars.


Assuntos
Variação Genética , Haplótipos , Herbicidas , Oryza , Oryza/genética , Resistência a Herbicidas/genética , Evolução Molecular
18.
Trends Plant Sci ; 29(9): 962-970, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38637173

RESUMO

Most high-yielding crops are susceptible to abiotic and biotic stresses, making them particularly vulnerable to the potential effects of climate change. A possible alternative is to accelerate the domestication of wild plants that are already tolerant to harsh conditions and to increase their yields by methods such as gene editing. We foresee that crops' wild progenitors could potentially compete with the resulting de novo domesticated plants, reducing yields. To improve the recognition of weeds, we propose using gene editing techniques to introduce traits into de novo domesticated crops that will allow for visual recognition of the crops by weeding robots that have been trained by machine learning.


Assuntos
Produtos Agrícolas , Domesticação , Plantas Daninhas , Produtos Agrícolas/genética , Plantas Daninhas/genética , Plantas Daninhas/fisiologia , Edição de Genes/métodos , Mudança Climática
19.
Front Plant Sci ; 15: 1354672, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510443

RESUMO

During the last decade, research has shown the environment and human health benefits of growing buckwheat (Fagopyrum spp.). This comprehensive review aims to summarize the major advancements made in the study of buckwheat from 2013 to 2023, focusing on its agronomic characteristics, nutritional value, and potential applications in sustainable agriculture. The review examines the diverse applications of buckwheat in organic and agroecological farming systems, and discusses the ability of buckwheat to control weeds through allelopathy, competition, and other sustainable farming methods, such as crop rotation, intercropping and green manure, while improving soil health and biodiversity. The review also explores the nutritional value of buckwheat. It delves into the composition of buckwheat grains, emphasizing their high protein content, and the presence of essential amino acids and valuable micronutrients, which is linked to health benefits such as lowering cholesterol levels, controlling diabetes and acting against different types of cancer, among others. Finally, the review concludes by highlighting the gaps in current knowledge, and proposing future research directions to further optimize buckwheat production in organic or agroecological farming systems. It emphasizes the need for interdisciplinary collaboration, and the integration of traditional knowledge with modern scientific approaches to unlock the full potential of buckwheat as a sustainable crop.

20.
Heliyon ; 10(4): e26381, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404847

RESUMO

Biological control of undesirable weeds associated with crop cultivation is a sustainable approach that can reduce chemical herbicide dependence. The current study aimed to assess the bio-herbicidal potential of the donor species Ononis vaginalis Vahl. on germination efficiency as well as various growth and physiological parameters of the recipient species Rumex dentatus L., a major broad bean pest (Vicia faba L.). To assess the greatest inhibitory allelopathic effect on the recipient species in mixed (Rumex dentatus L. and Vicia faba L.) and pure cultures (each one separately), two experiments were conducted under laboratory conditions. A Petri dish experiment using O. vaginalis shoot aqueous extract (5%, 10%, 20%, and 40%) and a pot experiment using O. vaginalis shoot crude powder (1%, 2%, 5%, and 10%) were conducted to investigate its biological activity on some growth and physiological parameters of both crop and weed species. O. vaginalis underwent a general phytochemical screening that revealed a high production of allelochemicals, which are secondary metabolites and may have a function like that of natural herbicides. The result showed that the germination of V. faba seeds in both pure and mixed cultures was not significantly affected by low levels of O. vaginalis shoot aqueous extract treatments in pure and mixed cultures, in contrast, those recorded for R. dentatus gradually dropped as levels of O. vaginalis increased in both cultures. Results recorded a significant increase in total phenolics of V. faba shoots and roots under different treatments, except at the high concentrations of crude powder at the donor species level (5 and10%). A reduction in the total phenolic and flavonoid fractions was observed in R. dentatus roots under varying concentration treatments. Conversely, under high concentration treatments, flavonoids decreased in the roots of the mixed culture of R. dentatus but increased in the shoots. In conclusion, allelopathy can be used to suppress weeds in field crops. The study confirmed the use of O. vaginalis into current weed control techniques. O. vaginalis could be explored further for weed suppression in the field.

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