Eleusine Indica Research Articles

Allelopathic Impact of Cover Crop Species on Soybean and Goosegrass Seedling Germination and Early Growth

Cover crops can provide a variety of benefits to an agricultural system: weed suppression, soil quality improvement, and soil water infiltration. Although there is ample research documenting weed suppression from cover crops, the mechanics of the suppression are not implicitly understood. Along with the aforementioned positive attributes, negative allelopathic effects on row crops planted into cover crop systems have been documented. The objective of this study was to evaluate the allelopathic potential of certain cover crop species on soybean (Glycine max L.) and goosegrass (Eleusine indica L.) germination and early seedling growth under controlled environments in petri dish and pot experiments. Leachates from above-ground biomass of five cover crop species, wheat (Triticum aestivum L.), cereal rye (Secale cereale), hairy vetch (Vicia villosa), crimson clover (Trifolium incarnatum L.), and canola (Brassica napus L.), from two locations (East and Middle Tennessee) were extracted and applied at 0 (water) and 50 v/v. In experiment I, both soybean and goosegrass seeds were examined, and, in experiment II, only soybean seeds were examined under the application of cover crop leachates. Most cover crop leachates from both locations significantly reduced the soybean seedling root length (p < 0.01). Overall, the application of canola extract (East Tennessee) suppressed soybean seed germination the most (28%) compared to deionized water. For goosegrass, the wheat cover crop leachate significantly reduced seedling root length (p < 0.01). In experiment II, the soybean root nodulation was significantly increased with the wheat extract treatment compared to deionized water. While the results indicate that the location and environment may change cover crop species allelopathic potential, the wheat cover crop leachate had the most potent allelopathic impact on goosegrass germination and growth; however, had the lowest observed adverse effect on our tested row crop, soybean.

Eight Species of Poaceae Are Hosting Different Genetic and Pathogenic Strains of Sugarcane Mosaic Virus in the Everglades Agricultural Area.

Sugarcane mosaic virus (SCMV) was detected by reverse transcription polymerase chain reaction in eight different species of the Poaceae family in the Everglades Agricultural Area (EAA) of south Florida: broadleaf signalgrass (Urochloa platyphylla), Columbus grass (Sorghum almum), goosegrass (Eleusine indica), maize (Zea mays), sorghum (Sorghum bicolor), St. Augustine grass (Stenotaphrum secundatum), southern crabgrass (Digitaria ciliaris), and sugarcane (Saccharum interspecific hybrids). Based on their coat protein (CP) gene sequence, 62 isolates of SCMV from Florida and 29 worldwide isolates representing the known genetic diversity of this virus were distributed into eight major phylogenetic groups. SCMV isolates infecting Columbus grass, maize, and sorghum in Florida formed a unique group, whereas virus isolates infecting sugarcane in the United States (Florida and Louisiana) clustered with isolates from other countries. Based on the entire genome coding region, SCMV isolates infecting sugarcane in Florida were closest to virus isolates infecting sorghum species or St. Augustine grass. Virus isolates from Columbus grass, St. Augustine grass, and sugarcane showed different virulence patterns after mechanical inoculation of Columbus grass, St. Augustine grass, and sugarcane plants, thus proving that these isolates were different pathogenic strains. Sugarcane was symptomless and tested negative for SCMV by tissue blot immunoassay after inoculation with crude sap from SCMV-infected Columbus grass, indicating that Columbus grass was not a reservoir for SCMV infecting sugarcane in the EAA. Close CP sequence identity between isolates of SCMV from Columbus grass, maize, and sorghum suggested that the same virus strain was naturally spreading between these three plants in south Florida.

Mitotic-inhibiting herbicide response variation in goosegrass (Eleusine indica) with a Leu-136-Phe substitution in α-tubulin

AbstractDithiopyr and dinitroanilines are preemergence-applied, mitotic-inhibiting herbicides used to control goosegrass [Eleusine indica (L.) Gaertn.] in turfgrass. A suspected resistant E. indica population was collected from a golf course putting green and was evaluated for possible resistance to dithiopyr and prodiamine. After dose–response evaluation, the α-tubulin gene was sequenced for known target-site mutations that have been reported to confer resistance to mitotic-inhibiting herbicides. A mutation was discovered that resulted in an amino acid substitution at position 136 from leucine to phenylalanine (Leu-136-Phe). Previous research has indicated that Leu-136-Phe does confer resistance to dinitroaniline herbicides. The level of resistance indicated by regression models and I50 values indicates that there is 54.1-, 4.7-, >100-, and >100-fold resistance to dithiopyr, prodiamine, pendimethalin, and oryzalin, respectively, when compared with the susceptible population based on seedling emergence response and 88.4-, 7.8-, >100-, and >100-fold resistance to dithiopyr, prodiamine, pendimethalin, and oryzalin, respectively, when compared with the susceptible population based on biomass reduction response. This is the first report of less resistance to prodiamine compared with pendimethalin or oryzalin due to a target-site α-tubulin mutation and the first report of a target-site α-tubulin mutation associated with dithiopyr resistance.

Characterisation of arbuscular mycorrhizal fungi community on black pepper (Piper nigrum L.) in Northern

Mycorrhiza was considered to enhance plant growth, especially in unfavourable environmental conditions. From 60 samples of rhizospheric soils and roots of black pepper (Piper nigrum) grown in Ba Ria - Vung Tau, Dong Nai, and Gia Lai provinces, the presence of Acaulospora, Gigaspora, Glomite, Glomus,and Scutellospora genera were detected, of which Glomus and Acaulospora were dominants. After 40 days of inoculation, mycorrhiza multiplied 8.5 fold on corn (Zea mays) and 6.5 fold on sorghum (Sorghum bicolor) or goosegrass (Eleusine indica). Black-pepper cuttings on substrate supplemented mycorrhiza showed better growth than the non-inoculated cuttings. Results suggest the potential of applying mycorrhizal fungi as biological agents in sustainable black pepper cultivation, adapting to climate change

Population growth rates of weed species in response to herbicide programme intensity and their impact on weed community

AbstractThe adoption of dicamba‐tolerant crops has reduced the challenge of controlling glyphosate‐resistantAmaranthus palmeriin these crops. However, introducing herbicide programmes with new mechanisms of action and different intensities can favour major shifts in weed communities. This can affect not only the functionality of the agroecosystem, but also resource availability to the most problematic species. The objectives of this work were to evaluate how herbicide programme structure and intensity affect (a) weed diversity, (b) population growth rate (λ) of weed species and (c) weed community structure based on λ dynamics in a dicamba‐tolerant cotton monoculture. To achieve these objectives, a cotton field experiment was established to compare four herbicide programmes from 2011 to 2018. The herbicide programmes differed in the first 4 years (i.e. glyphosate every year, alternating glyphosate and glyphosate plus dicamba every other year, glyphosate plus dicamba every year, and residual herbicide and glyphosate plus dicamba every year). During the last 4 years, all programmes received glyphosate plus dicamba. The weed seedbank was evaluated every spring and λ calculated. Environmental variation from year to year was more important in determining weed richness than herbicide programmes, which exhibited similar richness across all treatments during the eight years of the study. Regardless of herbicide programme, most species maintained λ between zero and one. Only a few species were the exception with λ values above one, such asA.palmeri,Mollugo verticillataandEleusine indica. Although glyphosate plus dicamba reduced λ for several species, this herbicide mix was less effective in reducing λ for other weeds compared with glyphosate alone, suggesting a potential antagonism that could change weed community composition. The limited changes in λ for most species suggest the capacity of weeds to adjust reproduction and survival to overcome changes in mortality rates caused by increases in herbicide use intensity.

Isolation, Identification, and Biological Characteristics of the Biocontrol Fungi NJC-16 for Eleusine indica

Isolation, Identification, and Biological Characteristics of the Biocontrol Fungi NJC-16 for Eleusine indica

Effect of Selected Weed Management Practices on the Growth and Yield Components of Finger Millet (Eleusine coracana) in Western Region of Kenya

Finger millet (Elusine coracana) accounts for 8% of the total area and 11% of the millet production worldwide. It is grown on over 4 million ha globally, mainly for food purposes. Millions of people in the dry lands of Central and East Africa, and South of India depend on finger millet as an important source of food to them (CGIAR, 2001). Finger millet is one of the most neglected and underutilized crops. Additionally, the crop has received limited research attention compared to wheat, rice, and maize (FAO, 2011). Therefore, production challenges such as those caused by weeds like goose grass Elusine indica remain at large. Manual weeding is the commonly employed weed control method in finger millet production, but is expensive and labour intensive. The current study was set to evaluate the influence of weed management practices on finger millet growth and yield components. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replicates. The plots measured 2 by 2m with a border width of 1m. The treatments included Pendimethalin, Dimethyl amine, Metolachlor, Metribuzin, Atrazine (at three rates each 1.0, 1.5 and 2.0 l/ha), No weeding and Hand weeding. Data was collected on the number of weed species, weed biomass, number of basal tillers, herbicide phytotoxicity, weed and crop heights, number of panicles, weight of panicles, weight of un-threshed and threshed grains and 1000 grain weight. Data was analyzed using one-way ANOVA using GenStat version 15.1. Application of Pendimethalin at 1.5 and 2.0 L/ha Active Ingredient (AI), resulted in weed optimal control and least phytotoxicity. Results also indicated that the height of finger millet was significantly (p<0.001) higher where the herbicides were applied. Lower weed biomass was also positively correlated with higher crop height, more panicles, high unthreshed and threshed weights and a 1000 grain weight. Application of 2,4D at rates of 1.5L and 2.0L resulted in significantly taller plants 33.00 cm, than the other weed management methods. Finger millet under Pendimethalin 1.5 L gave the highest number of 86 panicles while Atrazine 2.0L and Pendimethalin1.5L methods of weed control, had significantly higher weight compared to all the other treatments. The 1000 seed mass across the treatments averaged 2.31 g while the on the untreated treatments had an average of 1.54 g. Weed control using pre emergence herbicides significantly (p<0.001) increased the yields of finger millet.

Classroom Experiments using Phytochemical Analysis of Weed (Eleusine Indica)

This study aimed to demonstrate simple classroom experiments by evaluating the phytochemical components of the extracts of weed (Eleusine indica). The purpose of this study is also to contribute effective use of natural resources in the locality by transforming traditional knowledge to the scientific way of using the medicinal plant to be used as raw materials in pharmaceutical industries. The weed was air-dried for ten days. It was then pulverized using an electric blender. The mixtures were allowed to stand for seventy-two hours to extract the bioactive components of the weed. The experiment used chloroform (polar) in extracting the secondary metabolites present in the weed. The mixtures were then filtered with a cheese cloth and concentrated in direct heat using a hot plate. The extract was placed in a beaker and was labelled as chloroform extract. The bottle was covered tightly to prevent evaporation of the solvent. The Phytochemical components present in the weed extracts were alkaloids, flavonoids, carbohydrates, diterpenes, and saponins. This study is expected to be one of the teaching model (since the experiments are simple). This study also is expected to identify the phytochemical components of weed, identify the phytochemical components of weed, and contribute to the effective use of natural resources.

Pre-emergence herbicidal activity and persistence of 2,4-di-tertbutylphenol in relation to soil types

Although 2,4-di-tert-butylphenol (2,4-DTBP) has demonstrated strong phytotoxic effect on various weedy plants in previous findings, research on its pre-emergence herbicidal activity in the soil is still scanty. The aim of this study was to investigate the effects of two soil types on pre-emergence herbicidal activity and persistence of 2,4-DTBP. The bioassay was carried out in a growth chamber where goosegrass [Eleusine indica (L.) Gaertn.] seeds were sown in different rates of 2,4-DTBP in two soil series under sterilized and non-sterilized soil conditions. Bioassays of each treatment were conducted in four replicates and arranged in completely randomized design. 2,4-DTBP exhibited potent pre-emergence activity as a root inhibitor where it completely inhibited (100% inhibition) of the root growth of E. indica in sandy loam soil at an application rate of 6.14 kg ai/ha. 2,4-DTBP was rapidly detoxified in silt loam soil as a result of high microbial activity where it completely lost its phytotoxicity by giving 100% emergence within 10 weeks even it was applied at an application as high as 20.4 kg ai/ha. However, 2,4-DTBP remained highly phytotoxic in sandy loam soil where it reduced the root and shoot growth by 47 and 36%, respectively, throughout 10 weeks duration of the investigation. The presence of microbes in non-sterilized soil further suggest that soil microbes may modify the chemical structure of the 2,4-DTBP, which in turn decreased its toxicity. The high level of pre-emergence herbicidal activity in conjunction with its biodegradation in silt loam soil imply that 2,4-DTBP may have potential for development as a natural-soil applied herbicide

Eleusine Indica for Food and Medicine

Eleusine indica, a perennial herb that belongs to the Poaceae family, is locally known as “rumput sambau”. The species can be found in the tropical regions and it is the only species of Eleusine in Malaysia. In India, some parts of the plant such as the roots and the seeds are used as food and can be eaten raw or cooked. The young seedling is also used as a side dish with rice, while the seeds are sometimes used as a famine food. Although this grass is not considered as food in Malaysia, the local people utilise it to treat various ailments such as hastening the placenta delivery after childbirth, pain relieve for vaginal bleeding, asthma, fever, urinary infection, haemorrhoids, and tonic for flu related symptoms. Due to wide spectrum of traditional usage, a complete review of E. indica which focusing on food and medicinal perspectives is necessary to organize and evaluate its potential for further studies and commercial exploitation. The information on the species was collected from scientific journals, books, and reports searched through available databases such as Google Scholar, PubMed, Directory of Open Access Journals, Science Direct, Bioline International, and Reaxys. Contextually, the present review reveals that apart from the roots, the plant is relatively safe to ingest. It represents a rich source of nutrients and contains therapeutic phytochemicals such as flavonoids, steroids, essential oils, cardiac glycosides, coumarins, fatty acids, anthraquinones, anthrones, triterpenes, tannins, and alkaloids. Thus, E. indica can be considered as a natural reservoir for both food and medicine.

Effect of sunnhemp (Crotalaria juncea L.) green manuring on weed dynamics in puddle transplanted rice-based systems

Effects of Crotalaria juncea green manure on weed dynamics in transplanted rice-based systems were investigated in a field study conducted over two cropping seasons, 2016 and 2017, at Ludhiana, India. The major weed species in the field, during the green manuring phase, included Cyperus rotundus, Digitaria ciliaris and Eleusine indica. The use of cover/green manure crops and their residues to suppress weeds has shown potential to manage weeds. In this context, green manuring/cover cropping has great potential and is feasible in a rice-wheat system in northern India as there is a 45 to 60 days’ fallow period between wheat harvest and transplanting of rice. C. juncea with 50 and 100 kg seed ha-1 recorded significantly lower density and biomass of aerobics weeds and weed density as compared to without green manure in both years; GM with 100 kg seed ha-1 had a more suppressing effect on weeds than green manuring with 50 kg seed ha-1. The residual effects of weed control treatments, applied during 2016 to succeeding transplanted rice crops, did not have any specific trend on weed density in 2017. The major weeds in green manuring crop were C. rotundus, D. ciliaris and E. indica. But in transplanted rice, Echinochloa colona, E. crus-galli and Leptochloa chinensis were major weeds

Mercury resistance and plant growth promoting traits of endophytic bacteria isolated from mercury-contaminated soil

Mercury (Hg) is a toxic trace element that can cause serious environmental problems. The main source of Hg contamination to soil across Indonesia is artisanal and small-scale gold mining (ASGM) and strategies to manage or remove Hg from soil are needed. This study isolated Hg-resistant endophytic bacteria from indigenous local grasses (Cynodon dactylon and Eleusine indica) growing in Hg-contaminated soils to identify potential inoculants that could increase plant growth and mercury uptake for phytoremediation. Grass samples were collected from an ASGM location on Lombok Island. The grass samples (both, root and shoot) were surface sterilized, aseptically mashed, and serially diluted with 0.9% sodium chloride (v/v) and an aliquot of the extracted bacteria was cultured on Nutrient Agar across a range of HgCl2 concentration from 0 to 1000 mg/L. Thirteen bacterial isolates were tested for their ability to detoxify Hg, Hg bioaccumulation, indole acetic acid (IAA) production, ammonium production, and siderophore production. Five of thirteen isolates were Hg-resistant and survived on a medium containing 250 mg/L HgCl2. One isolate from each of E. indica and C. dactylon showed complete Hg detoxification. The greatest Hg bioaccumulation was 85.04%. The highest expressed IAA and ammonium concentration was 13.17 mg/L and 2.58 mg/L respectively. Based on 16S rDNA sequence similarity, the two isolates with the greatest potential as inoculants (CD6 and EI6) were identified as Jeotgalicoccus huakuii (isolated from C. dactylon) and Bacillus amyloliquefaciens (isolated from E. indica) and could be used as inoculum for phytoremediation of Hg-contaminated soil in future studies.

Fitness of Paraquat Resistant and Susceptible Biotypes Population of Goosegrass (Eleusine indica (L.) Gaetrn.)

A biotype of Paraquat resistant goosegrass (Eleusine indica (L.) Gaertn.) has envolved in an oil palm plantation in North Sumatera after been treated with Paraquat herbicide in a long period of time. This study aims to investigate the fitness of Paraquat resistant biotype when growing with susceptible biotype in the absence of herbicide. Seeds of Paraquat resistant biotype of Eleusine indica were collected from an oil palm plantation in Deli Serdang and had been proven to have resistant of Paraquat herbicide whereas the susceptible population from a field near campus of Universitas Sumatera Utara which never been exposed to Paraquat herbicide. Both biotypes were planted with proportions of 100 R: 0 S, 75 R: 25 S, 50 R: 50 S, 25 R: 75 S, and 0 R: 100 S with four replications. The result showed that Paraquat resistant biotypes had stronger fitness that the susceptible biotypes.

The Effectiveness of Weed as Beetle Bank Against Abundance of Soil Arthropods on Corn (Zea mays. L)

Conservation of natural enemies on maize can be done by utilizing grass weeds as Beetle banks. Natural enemies of shelter and get food from the weed grasses that are in the land irrigated corn. Natural enemies observed in this research were the predator of ground arthropods in the form of ground beetles, tomcat, and predators arthropods in other lands. The trap used is the Pitfall trap. The percentage of arthropod predators was 69%, and arthropods herbivore was 31%. The abundance of soil arthropods in the treatment of weeds grass is higher than the control treatment It is because of the treatment of weed grass soil arthropods get habitat for a place to stay. Weed grasses provide food sources for the arthropods and get protection from an environment that is less supportive. The use of weed grasses in addition to Beetle banks also serves as a place to breed. The highest abundance of arthropods was situated on the treatment Eleusine indica that has a lush lawn and has a characteristic odor favored by arthropods. Arthropods that acts as a predator in the land are the family of Formicidae, Philodromidae, Carabidae, Staphylinidae, Pentatomidae. Some Arthropods from the Pentomidae family have a role as a pest and others as natural predators or predators. Arthropods found in the research was an arthropod that had a role as natural enemies or predator. The Pentomidae family that has a position as a predator is Picromerus Bidens. Ground beetles were found in the C. fossor and Pheropsophus sp. Ground beetles are dominant picking weeds Setaria sp. and Eleusine indica as habitat and place in search of food and life’s survival. Keywords: Beetle bank, soil arthropods, weeds.

Differences in selectivity between bermudagrass and goosegrass (Eleusine indica) to low-rate topramezone and metribuzin combinations

AbstractGoosegrass [Eleusine indica (L.) Gaertn.] remains problematic for bermudagrass [Cynodon dactylon (L.) Pers.] turf managers due to the ineffective, selective control of mature plants with available postemergence herbicides and lack of sufficient residual activity from those herbicides to control seedling plants. Topramezone controls mature E. indica, but past efforts to suppress potential injury to bermudagrass turf have been inconsistent. We hypothesized that metribuzin at 210 g ai ha−1 in admixture with topramezone would improve bermudagrass tolerance while conserving mature E. indica control. In preliminary field studies, metribuzin mixed with topramezone at 1.2 or 2.5 g ae ha−1 applied twice at a 3-wk interval reduced bermudagrass injury and white discoloration compared with topramezone applied alone, but metribuzin did not safen bermudagrass to mesotrione. Topramezone at 3.7 g ha−1 plus 210 g ha−1 metribuzin applied twice at a 3-wk interval offered improved bermudagrass tolerance while it still controlled mature E. indica during 15 field and 2 greenhouse studies in Virginia. This program offered a 10-fold decrease in suprathreshold duration of white discoloration compared with topramezone alone at 6.1 g ha−1. Bermudagrass absorbed three times less radioactivity than E. indica at timings up to 48 h after treatment with [14C]topramezone. Bermudagrass also metabolized twice as much topramezone compared with E. indica at 48 h after treatment. Metribuzin reduced 14C absorption by approximately 25% in both species. These studies confirm the performance of a novel, low-dose topramezone plus metribuzin program for mature E. indica control in bermudagrass turf and suggest that selectivity between bermudagrass and E. indica to topramezone is due to differential absorption and metabolism. The fact that metribuzin reduces topramezone absorption in both species suggests that it may help reduce bermudagrass phytotoxic response to topramezone, but its role in altering selectivity between bermudagrass and E. indica may be due to other factors.

Selection of transgenic citrus plants based on glyphosate tolerance conferred by a citrus 5-enolpyruvylshikimate-3-phosphate synthase variant.

We have defined the conditions for citrus transformations using glyphosate as selection agent. This protocol results in high transformation rate and low incidence of chimeric shoots. Glyphosate, the most widely used herbicide in the world, specifically inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an essential enzyme of the shikimate pathway. Various laboratory-generated or naturally evolved glyphosate-resistant EPSPS variants have been used to produce glyphosate-tolerant transgenic crops, enabling highly effective weed control in agriculture. In this study, we explored the potential of using a citrus EPSPS variant that mimics the previously reported Eleusine indica glyphosate-resistant TIPS (T102I + P106S) mutant for selection of transgenic citrus plants in the presence of glyphosate. We found that glyphosate did not suppress bud formation on 'Duncan' grapefruit seedling explants, but inhibited non-transgenic bud outgrowth to produce shoots in a concentration-dependent manner. At certain concentrations, glyphosate had dramatic effect on the transformation rate and the percentage of non-chimeric transgenic shoots in this newly developed selection system. Specifically, at 0, 10, 20, and 50 μM of glyphosate, the citrus TIPS EPSPS-based selection resulted in transformation rates of 4.02, 5.04, 14.46, and 40.78%, respectively, and 6.41, 23.96, 42.94, and 40.17% of non-chimeric transgenic shoots, respectively. These results indicate that the citrus TIPS EPSPS-glyphosate selection system is highly efficient and can be used as an alternative to antibiotic-based selection methods in citrus genetic transformation. Furthermore, the selection conditions defined in this study are expected to greatly facilitate the production of genetically modified, market-friendly citrus plants, such as cisgenic and intragenic plants.

Endophytic bacteria isolated from a weed plant as a potential biocontrol agent against stem end rot pathogen of pitaya in Vietnam

BackgroundStem end rot (SER) disease caused by Alternaria alternata is one of the main fungal diseases in pitaya and other crops in Nam Dinh, Vietnam, that leads to extensive yield and economic losses. Biocontrol of SER, using endophytic bacteria, is environmentally friendly and compatible with other control measures. Hence, it is emerging as an alternative disease management strategy in sustainable agriculture. This study aimed to screen antagonistic bacteria isolated from the weed, Eleusine indica, with the potential to manage SER.ResultsA total of 16 endophytes were isolated from the stems, leaves, and roots of the weed, E. indica. Of those, 6 strains presented antagonistic effects against A. alternata growth, and one isolate, EI-15, showed a significant inhibitory effect on SER. In addition, analyzing the 16S rDNA sequence indicated that EI-15 was a strain of Bacillus amyloliquefaciens. Moreover, the results of the antagonistic spectrum assay showed that EI-15 significantly inhibited some plant and fruit tree pathogens, especially the suppression of A. alternata. Notably, the culture filtrate of strain EI-15 exhibited in vitro apparent activity against A. alternata. Furthermore, an in vivo antagonistic experiment of EI-15 on pitaya twig showed a significant reduction of lesion on twigs than the control.ConclusionsOverall, this study suggested the potential application of the EI-15 strain as a biological agent and needs to be further studied in the field to control SER.

Cover Crop Residue Effects on Soil and Corn Performance in Ex-Nickel Mining Soils.

<b>Background and Objective:</b> The use of cover crop residue for improving soil quality has been widely applied. Nevertheless, the effectiveness for improving ex-mining soil quality and crop performance at ex-mining soils is rarely documented. This study investigated the effect of cover crop residue on soil quality enhancement and corn production established in ex-nickel mining soils. <b>Materials and Methods:</b> An experiment comprising three treatment of cover crops residue, including <i>Eleusine indica, Centrosema pubescens</i> and <i>Calopogonium mucunoides</i>, arranged in a completely randomized design with three replications. The soil improvement process was evaluated by several parameters, such as soil acidity, soil organic carbon, total nitrogen, exchangeable potassium, exchangeable magnesium and heavy metals. On the other side, corn's growth performance was assessed using some attributes, i.e. height, diameter, total leaves, leaf area and biomass accumulation. <b>Results:</b> The results demonstrated that the cover crops residue had the potential to improve ex-nickel mining soil quality. The highest soil improvement was recorded in total nitrogen (700-800%). The treatments also showed a positive advantage to reduce heavy metals content, particularly for Fe, Mn and Zn by approximately 51.58-85.74%. No significant difference in corn growth performance was found in this study (p>0.05). However, the utilization of crop residue from <i>Calopogonium mucunoides </i>exhibited relatively higher total biomass than other treatments by around 3.08±1.99 g plant<sup>1</sup>. <b>Conclusion:</b> Despite the treatments had no significant effect on corn performance. This study realized that cover crop residue could improve soil conditions for providing better environmental conditions for agriculture development.

Herbicidal properties of antihypertensive drugs: calcium channel blockers

Herbicide resistance is a worldwide problem in weed control. This prompts researchers to look for new modes of action to slow down the evolution of herbicide-resistant weeds. This research aims to determine the herbicidal action of thiazolo[3,2-a]pyrimidines derivatives, which are well known as antihypertensive drugs. The phytotoxic effects of ten compounds were investigated using leaf disc discoloration test and seed germination bioassay. At concentrations of 125 to 250 mg/L, the 5-(3-Fluoro-phenyl)-7-methyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester (c) was highly active against Oldenlandia verticillata and Eleusine indica. At application rates of 1.25 to 2.5 kg ai/ha, formulated c demonstrated selective post-emergence and pre-emergence herbicidal activity against O. verticillata, E. indica and Cyperus iria. In the crop tolerance test, formulated c outperformed the commercial herbicide diuron, with aerobic Oryza sativa being the most tolerant, followed by Zea mays, and Brassica rapa. The addition of calcium chloride partially nullified compound c's inhibitory effects on weed shoot growth, indicating that it has potential as a calcium channel blocker. Compound c acted by triggering electrolyte leakage without affecting photosystem II. These findings imply that c could be explored further as a template for developing new herbicides with novel modes of action.

Evolution of multiple target-site resistance mechanisms in individual plants of glyphosate-resistant Eleusine indica from China.

Glyphosate has been used for weed control in South China in various situations for four decades, and most Eleusine indica populations are suspected to have evolved resistance to glyphosate. This research investigated underling target-site glyphosate resistance mechanisms in six field-collected, putative glyphosate-resistant (R) E. indica populations. The six R E. indica populations were confirmed to be low (1.8 to 2.6-fold) to moderately (5.6- to 8.4-fold) resistant to glyphosate relative to the susceptible (S) population. Sixty-seven glyphosate-surviving plants from the six R populations were used to examine target-site resistance mechanisms. Target-site 5-enolpyruvylshikimate3-phosphate synthase (EPSPS) overexpression (OE) (plus further induction by glyphosate treatment) and gene copy number variation (CNV) occurred in 94% R plants, and among them, 16% had the P106A mutation and 49% had the heterozygous double TIPS (T102I + P106S) mutation (plus P381L). In addition, a low number of R plants (6%) only had the homologous TIPS (plus P381L) mutation. The (CT)6 insertion mutation in the EPSPS 5†-UTR always associates with EPSPS OE and CNV. Progeny plants possessing EPSPS OE/CNV (and P106A) displayed low level (up to 4.5-fold) glyphosate resistance. In contrast, plants homozygous for the TIPS mutation displayed higher (25-fold) resistance to glyphosate and followed by plants heterozygous for this mutation plus EPSPS OE/CNV (12-fold). Target-site glyphosate resistance in E. indica populations from South China is common with prevalence of EPSPS OE/induction/CNV conferring low level resistance. Individual plants acquiring both the TIPS mutation and EPSPS OE/CNV are favored due to evolutionary advantages. The role of (CT)6 insertion mutation in EPSPS CNV is worth further investigation. © 2021 Society of Chemical Industry.