Broad Leaf Research Articles

Degradation of isoproturon in vitro by a mix of bacterial strains isolated from arable soil.

Isoproturon (IPU) is widely used to control annual grasses and broad leaf weeds in cereal crops. In this study, four IPU-degrading bacterial strains, i.e., Sphingomonas sp. ISP1, Arthrobacter sp. ISP2, Acinetobacter baumannii 4IA, and Pseudomonas sp. ISP3, were isolated from agricultural soil. The mixed culture of four isolates completely degraded the herbicide at 100mg/L within 10 days. During IPU degradation, several transient accumulations of the metabolites, including 3-(4-isopropylphenyl)-1-methylurea, 3-(4-isopropylphenyl)-urea, 4-isopropylaniline, and 4-toluidine, were also identified. Moreover, the inoculation of the isolated mixed culture into the soil from a mountain with no previous herbicide application increased the degradation rate by 51% of the herbicide on average. Furthermore, bioaugmentation with isolated bacteria in the soil resulted in short-term variations in bacterial structure compared to the unaugmented soil. The findings of this study were instrumental in understanding the mechanisms of pesticide breakdown and bioremediation in liquid media and soil.

Modulation of atrazine-induced chromosomal aberrations and cyclin-dependent kinases by aqueous extract of Roylea cinerea (D.Don) Baillon leaves in Allium cepa

Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.

Effect of Plant Density and Propnit Herbicide on the Weeds and Grain Yield of Sorghum

A field experiment was carried out during the spring season of 2020 in the experimental field of the College of Agricultural Engineering Sciences - University of Baghdad - Abu Ghraib to know the effect of weed controlling broad and narrow leaf weeds and grain yield of sorghum (Inqath cultivar). Randomized complete block design (RCBD) was used according to split plots at three replications. The main plots included three weed control treatments (spraying of propnit herbicide at the recommended dose of 450-500 ml dunum-1 and half recommended dose of 225-250 ml donum-1) and weedy and free weedy treatments. In contrast, the subplots included three plant densities (1.0×105, 1.5×105, and 2.0×105, plants ha-1). The results of the statistical analysis indicate that the spraying of herbicides Proponit at the recommended concentration recorded the lowest average density of broad and narrow leaves (7.89 7 and 2.22 plants m-2) and the highest percentage of controlling broad and narrow leaves (72.17 88.03%) and the highest percentage of inhibiting the dry weight (75.33%). As for the effect of plant density, the results indicated that there was a significant effect of plant density in most of the studied traits, where the plant density recorded 200 thousand plants ha-1, the lowest numerical density for broad leaves and the percentage of their control (4.79 plants m-2 and 69.74%), and the plant density recorded 100 thousand The plant ha-1 had the highest inhibition rate of 63.53%. The plant density exceeded 150 thousand plants ha-1, and the highest grain yield was 6.03 tons ha-1. The different combinations between the two studied factors significantly affected most of the studied traits.

Efficient Herbicide Delivery through a Conjugate Gel Formulation for the Mortality of Broad Leaf Weeds.

Carfentrazone-ethyl is embedded in guar gum to prepare a polymer–herbicide conjugate gel formulation for a sustained release of the active ingredient (a.i.). The sprayable gel formulation was optimized at 0.5% (w/v) concentration. Strong interactions of the prepared composition of the polymer–herbicide conjugate system are shown through spectroscopic techniques, depicting the peak broadening of hydrophilic −OH bonds in the herbicide at 1743 cm–1, shifting to 1730 cm–1 in the polymer–herbicide sample. There is a broadening and shifting of the peak at 329 nm for the n → π* transition at 335 nm in the polymer–herbicide conjugate system in UV spectra. Differential scanning calorimetric measurements show a lowering of endothermic melting peaks to 242 and 303 °C in the polymer–herbicide conjugate. X-ray diffraction studies showed a sharp diffraction peak of the pure polymer at a 2θ of ∼20.3°, while broadening and shifting of the peak position to a 2θ of ∼20.8° were observed after adding the herbicide. Diffusion of the active ingredient in the polymer–herbicide conjugate resulted in much greater coverage (most of the weed leaf stomata (>95%)) than conventional spraying. The efficacy of both the polymer–herbicide formulation and herbicide at different doses in weed nurseries showed significantly higher weed mortality in Anagallis arvensis (95.4%), Chenopodium album (∼97%), and Ageratum conyzoides (93.16%) treated with the polymer–herbicide formulation @ 20 g a.i. ha–1. Narrow SPAD readings range of A. arvensis (0.1–30.6) and that of C. album (0–5) were observed in the polymer–herbicide formulation @ 20 g a.i. ha–1 was at par with the conventional formulation @ 30 g a.i. ha–1. Less regeneration in a weed nursery of A. arvensis (27%), C. album (77%), and A. conyzoides (49%) treated with gel formulations @ 20 g a.i. ha–1 was observed, which was significantly lower than those in conventional herbicides.

Carbon Regulating Services of A 30-year-old Reclaimed Limestone Mine Area in Foothills of Himalaya

The study aims to assess various carbon regulating services of a limestone mine site, reclaimed 30 years back, compared to its adjoining natural forest. The natural forest is dominated by broad leaf species ( Quercus leucotricophora ) whereas, the reclaimed sites have Cupressus torulosa as the dominant species. Though there was no significant difference in the number of species of various life forms (trees, shrubs, herbs and grasses), total basal cover (TBC) estimated for the natural forest (2513.36cm 2 /100m 2 ) was much higher compared to the reclaimed site (584.30 to 997.07 cm 2 /100m 2 ). The difference is much higher in TBC of trees compared to shrubs. Annual litter production was also higher in the natural forest. Microbial activity in the top soil layer was found to have increased substantially in the reclaimed mine site. Soil respiration rate and soil microbial biomass in the reclaimed mine site was on a par with that of natural forest. It indicates a significant level of organic matter and detritus availability in the reclaimed sites' top soils since the soil's degradable organic carbon is the main fuel responsible for the CO emission during soil 2 respiration. Though the carbon assimilation rate recorded in the vegetation of the reclaimed area is on a par with that of vegetation of natural forest at the species level, at the community level, the reclaimed site may have lower assimilation owing to lower TBC. Therefore, the difference in vegetation structure and composition in the reclaimed site compared to the natural forest might significantly impact the overall carbon regulating services in the study area.

Determination of Efficacy of Broad Leaf Herbicides on Various Weed Floras in Wheat Field under Rain Fed Production System

Determination of Efficacy of Broad Leaf Herbicides on Various Weed Floras in Wheat Field under Rain Fed Production System

Shallow surface elevation changes in two tropical seagrass meadows

The ability of seagrass meadows to reduce surface erosion and maintain or increase surface elevation is recognised as an important ecological function, which is expected to help protect coastlines. However, much of the evidence supporting this expectation is limited to large, broad leaf, subtidal populations of seagrass from temperate regions. In this study, we examined the capacity of shorter-stature, intertidal seagrasses to influence sediment deposition and shallow surface elevation change compared to unvegetated surfaces at two locations in Singapore. At each location, sediment supply, sediment deposition and surface elevation change were measured over 270 days, a temporal period covering two monsoonal seasons. The levels of these factors were compared among locations and seasons. Overall, surface elevation in vegetated areas increased by 0.40 ± 0.26 cm, while surface elevation in unvegetated areas declined by 0.34 ± 0.31 cm. We also explored the influence of key meadow characteristics on sediment deposition and surface elevation change, and found that surface elevation increased with aboveground biomass, while sediment deposition increased with areal production, leaf turnover rate and belowground biomass. These results suggest that short-term sediment deposition and broader net surface elevation increases moderately in the presence of seagrass compared to unvegetated areas, and highlight the potential of intertidal, short-stature seagrasses such as Cymodocea rotundata to increase surface elevation.

Studies on Pest Complex of Broad Leaf Mustard, Brassica juncea var. rugosa Roxb. Tsen and Lee in the Valley of Manipur

A experiment was conducted at Entomological Research Farm, Department of Entomology, College of Agriculture, Central Agricultural University, Imphal. Total eleven insect pest species were found to infest the crop viz. Large cabbage white butterfly, Pieris brassicae; Asian cabbage white butterfly, Pieris canidia; mustard aphid, Lipaphis erysymi and striped flea beetle, Phyllotreta striolata were observed frequently while, Cabbage aphid, Brevicoryne brassicae; green peach aphid, Myzus persicae; crucifer flea beetle, Phyllotreta cruciferae; mustard sawfly, Athalia lugens proxima; cabbage semilooper, Trichoplusia ni; fungus beetle, Monolepta signata and tobacco grasshopper, Atractomorpha crenulata were observed rarely.

Smilax weniae, a New Species of Smilacaceae from Limestone Areas Bordering Guizhou and Guangxi, China.

A new species, Smilax weniae (Smilacaceae), from Southwest China, is described and illustrated. The new species bears peltate leaves, which was previously a unique feature of S. luei. However, it differs from the latter by having a broad ovate leaf blade, longer peduncle, and sexual dimorphic flowers. Further phylogenetic analyses revealed that the new species were placed in a unique position in a subclade of Old World Smilax based on ptDNA and nrITS sequences. Combining detailed morphological comparisons and molecular evidence, we validated that S. weniae is an undescribed new species. Moreover, the plastome characteristics of S. weniae are reported.

Struktur Makroskopis dan Mikroskopis Fosil Kayu Asal Desa Bangun Rejo, Kabupaten Kutai Kartanegara

Observation of the macroscopic structure included color, hardness and density, while microscopic observations were carried out through three sections, namely the Transverse, Tangential, and Radial sections, using Stereo Microscope NIKON SMZ 645 and Research Microscope Eclipse E400 (equipped with a Nikon camera). The counted cells were: Pores (diameter, height, number), Rays (height, width, number), and the percentage of cells. The hardness value was calculated by using a rock hardness tester, namely 'Diamond Selector II'. Meanwhile, specific gravity was calculated by using general calculation standard for specific gravity, namely the ratio of mass to volume. The results showed that microscopically the two samples of wood fossils found were hardwood fossils (broad leaf wood) whose species was not yet known, with the characteristics of mostly solitary pores, uniseriate rays with heterogeneous arrangement. Meanwhile, the macroscopic observations of wood fossils FKM1 showed dark brown, light brown and a mixture of red. The second FKM2 showed light brown, yellow and dark brown colors. The hardness both was 4 on the Mohs scale, while the density were 3.25 and 3.04, respectively.

REMOVAL OF HEAVY METALS AND AGROCHEMICALS RESIDUES THROUGH PLANTS

The present paper presents about removal of heavy metals, agrochemicals residues through natural plants. The removal of heavy metals residues and agrochemical residues with the interception of natural plants is called phytoremediation. The advancement of applied research produced various phytoremediation plants like weed plant, aquatic plant, tree and crops. The natural plant eradicates heavy metals and agrochemicals residues through phytostabilization, rhizodegradation, rhizofilteration, phytodegradation and phytovoltalization process. The terrestrial and aquatic plant eradicates heavy metals and agrochemicals residues from soil and water. Indian mustard removes 3 fold Cd, Pb, Se and Cs radioactive metals and diesel fuel spillage. Oryza sativa L. is cereal crop, removes Cu, Cd, from contaminated soil. Spinacia oleracea (Spinach) is vegetable crop, removes Cd, Cu, Fe, Ni, Pb, Zn and Cr from contaminated soil. Cicer arientinum is pulse crop, eradicates Pb and Cr from the contaminated soil. Pea is vegetable crop plant, removes Cd from the contaminated soil. Brassica napus L. oilseed crop, removes Cd, Cu, Zn, Pb from the contaminated soil. Cajanus cajan L. is pulse crop, removes As, Cd from the contaminated soil. Cucumis sativus L. is vegetable crop, removes Pb from the contaminated water. Annual grass and broad leaf weed removes atrazine, simazine, propazine, prometryn from the soil. Chenopodium album L., Hordeum juhatum L., Panicum capillare L., Nepeta cataria L., Caedus nutans L., Poa annua an Fostuca sp. removes atrazine, phosphorus, nitrate, ammonium. The phytoremediation plant recovers natural resources and restricts outbreak of diseases in the nature. Further, the scientific studies and research may build products of phytoremediation controlled plants for removing heavy metal and agrochemicals residue from the soil.

Physiological and agronomic responses to the application of post-emergence herbicides on sweet potato cultivar selected for its potential as biofuel feedstock

Sweet potato exhibits a prostrate growth habit, which makes weed management to be manually performed or conducted through the application of selective herbicides. Considering the absence of registered herbicides for the selective control of broad leaf weeds on the sweet potato crop, we investigated the physiological and agronomic responses of the sweet potato cultivar Duda, selected for its great potential in biofuel production, to different post-emergence herbicides. Two experiments, one conducted under field conditions and the other under controlled (potted plants) conditions, were performed under a randomized complete block design, with four replicates each. Four different herbicides, atrazine and S-metolachlor (3,5 L.ha-1), carfentrazone-ethyl (0,75 L.ha-1), fomesafen and fluazifop-P-butyl (1,8 L.ha-1) and nicosulfuron (1,25 L.ha-1), were used and the experiments were composed by five treatments with the control (no herbicide application) treatment,. Physiological indicators, including carbon assimilation, stomatal conductance, leaf transpiration rate, internal CO2 concentration, and water-use efficiency were monitored at 24 h, 48 h and 15 d after herbicides application, while agronomic evaluations were performed at 30 and 152 days from herbicide application. Application of atrazine (inhibitor of photosystem II) together with S-metolachlor (inhibitor of cell division/elongation) led to reductions on the physiological indices soon after treatment imposition but it had no effect on dry matter accumulation in the shoot, nor on the roots, not affecting the starch content, storage root productivity, and estimated ethanol production as well. In contrast, application of carfentrazone-ethyl, a protoporphyrinogen oxidase inhibitor, exerted significant negative physiological and agronomic effects, decreasing root productivity and estimated ethanol yield. We conclude that the use of atrazine in a mixture with S-metolachlor represents a suitable selective approach for the control of broad leaf weeds in sweet potato crops.

Determination of Carbon, Nitrogen and Phosphorus Stocks and Stoichiometry in Broadleaf Mixed Forest Soil and Litterfall: A case study in Oltu district, Erzurum

It is necessary to provide plant nutrients in soil at optimal levels for the sustainability of forest ecosystems. The soil stoichiometry of total carbon (C), total nitrogen (N) and total phosphorus (P) allow monitoring and assessment of ecosystem structures and variations in nutrient cycle. Studies on determination of C-N-P stoichiometry in forest ecosystems, however, are somewhat inadequate. This study aims to determine change of C-N-P stoichiometry depending on litterfall condition and soil depth in broadleaf mixed forest (Europen Hophornbeam - Syspirensis Oak) soil and the C-N-P stocks in soil. In this context, we were determined both C-N-P stoichiometry and C-N-P stock in soil and litterfall by conducting field studied at 10 different points in the Broad Leaf Mixed Forest of Erzurum-Oltu district. The results indicated that as the depth of the soil increased, the C-N ratio decreased, whereas the N-P and the C-P ratios increased. Positive correlations were observed between C-N in all soil depths, but negative correlations between C-P and N-P. The correlation coefficients between C and N (r0-10= 0.58, r10-20= 0.52 and r20-30= 0.44) and between C and P (r0-10= 0.64, r10-20= 0.54 and r20-30= 0.42) and between N and P (r0-10= 0.52, r10-20= 0.35 and r20-30= 0.36) decreased as soil depth increased. The mean scores of the C-N-P stocks were determined as 5.9, 1.3, and 0.2 ton ha-1 in litterfall and 157.68, 24.60, and 2.68 tons ha-1 in soil, respectively. It is important to rehabilitate degraded forests and minimize the negative effects of erosion in order to increase the amount of carbon captured in forest soils. In addition, the variable C: N: P stoichiometry in forest ecosystems; It can be considered as a leading indicator of soil degradation and drought and climate changes.

Study of diversity in thermo-tolerant advanced lines of Wheat (Triticum aestivum L.) for Morpho-physiological, Yield and its Contributing Traits

The present study was carried out to examine the genetic diversity among 151 thermo-tolerant advanced breeding lines of wheat for two experimental years during Rabi 2017-18 and Rabi 2018-19 in randomized block design in an area of 312 m2 at Field Experimentation Center, Department of Genetics and Plant Breeding, SHUATS, Allahabad. The data were recorded in both the seasons for total 23 traits i.e. 18 quantitative characters to study variability, heritability, genetic advance and genetic divergence and 5 morphological characters. ANOVA showed significant differences for all the characters except flag leaf width, in both experimental seasons and for gluten content in season Rabi 2018-19 indicating the presence of a substantial amount of genetic variability which thus revealed different genetic backgrounds of genotypes. High estimates of both GCV and PCV were observed for biological yield in both experimental years. High heritability with high genetic advance was recorded for all quantitative characters except flag leaf width and gluten content indicating the predominance of additive gene effects and hence the possibilities of effective selection for the improvement of these traits. D2 analysis grouped these lines into 10 clusters in which cluster VII was biggest cluster with 26 lines. Further diversity analysis revealed that cluster IV and VII followed by Cluster VI and Cluster VII were most divergent from each other, and the genotypes present in them may be used as parents for further hybridization program to develop desirable heat type in wheat. Analysis of 5 Morphological characters i.e. leaf type, rachis colour, leaf shape, waxiness and stay green habit, depicted that HUW-213 x NW-1076 followed by HALNA x RAJ-4037 were found above average yielders and terminal heat tolerant primarily due to their semi-erect leaf type, green rachis color, broad leaf shape, stay green habit and less days to maturity as compared to checks.

Assessments and Identification of Major Weed of Hot Pepper (<i>Capsicum annuum</i> L.) in West Shoa and East Wollega Zones, Ethiopia

Hot pepper is the most important vegetable crop belonging to the family Solanaceae and grown as a spice crop in different parts of the world. Hot pepper is one of the important cash crops to Ethiopian smallholder farmers and an important agricultural commodity which contributes to export earnings. Peppers cultivation in the field are subject to biotic and abiotic factors effects that influence the yield. Weeds emerge fast and grow rapidly competing with the crop for growth resources viz., nutrients, moisture, sunlight and space during entire vegetative and early reproductive stages of hot pepper. there is a dire need of identification major hot pepper weed in the study area for develop management option and this activity was initiated to assess and identify distribution and status of major hot pepper weeds in the study area. The weed survey was conducted in West Shoa and East Wollega Zones of Oromia Reginal state during 2020 main cropping season. The weed Survey was conducted to assess Abundance, Dominance and Frequency of major Hot pepper weeds. Kebeles were randomly selected from each District and based on the representativeness of hot pepper production of the area. Weed survey was performed along two diagonals (“X” pattern) of a five points field of 1m x 1m (1 m²) quadrates. A total of 46 weed fields were surveyed from Hot Pepper farms of Ilu Galan, Bako Tibe, Sibu Sire and Boneya Boshe Districts. From study fields 15 weed family and 39 weed species were recorded and identified. The assessments result also showed that, Broad leaf weeds dominate over grass and sedge weed species. 76.92% broad leaf, 17.95% grass types, and 5.13% sedge types from a total of 39 weed species of hot pepper farm fields. The occurrence of each weed species ranged from 2.78 up to 97.22% while the dominance value ranged from 0.3% up to 28%. The most common and prevailing weed was Ageratum conyzoides L. and Guizotia scarab in hot pepper field. Hence when developing a weed management approach in the future, different weed controlling options must be planed next coming years, toward those major Weed families and species; especially broad leaf weed.

Bending test and batting by players for the strength analysis of baseball bats made of Dakekanba tree in Hokkaido

Dakekanba is a broad leaf tree popular in Hokkaido. We cut a few trees out of the Teshio research Forest of Hokkaido University. Commercial grade baseball bats were manufactured from the timber. The quality of the bat was examined by laboratory test and also by hitting balls in play fields. The laboratory tests were done by three-point bending to measure the bending load to have the bat broken. The strength in average was much higher than the manufacturer standard for wooden bats. It was found that the breakage occurred in different way showing different paths of cleavage fracture. Some bats showed typical mode of multiple pieces failure (MPF), which should be avoided because of possible accident in play field. The MPF was also found in the bats broken by player. The origin of MPF was examined.

A REVIEW ON EFFECT OF WEEDS IN WHEAT (TRITICUM AESTIVUM L.) AND THEIR MANAGEMENT PRACTICES

Wheat is the second most important cereal crop in the world. It has a vital role in the human diet globally, contributing to the daily calorie and protein intake than any other cereal crops. The productivity of wheat is low because of different biotic and abiotic factors. Weeds are one of the most important competitors of wheat crop. Understanding the nature of weeds is important to develop techniques to reduce their effects on the crops. Weeds, through competition with other crops, almost always have a deleterious effect on them and may be economically and environmentally detrimental. For world food sustainability controlling the weed-induced yield losses in the wheat is of prime importance because the weeds compete with the crop and also possess deleterious effects. There are various weed species that occur in the wheat crop field and they possess effects on the growth phases of wheat. Allelopathic effects of weeds on the germination, growth and yields on the crops are recorded. The variation in the vegetative traits such as the number of fertile tillers, spike length, grains/spike due to weeds is reflected ultimately in grain yield and quality. Both broad leaf weeds and narrow leaf weeds infest the wheat crop causing a 13.1% reduction in total grain yield globally. Although tillage operations and herbicides use have played an important role in weed control, but their indiscriminate use has resulted in unacceptable consequences on humans as well as vital ecosystems along with the evolution of herbicides resistance genotypes. Through a combination of integrated weed management approaches the crop competitiveness against the weed can be increased which results in the reduction of the weed-induced yield losses in wheat. The main purpose of this study is to review the competition of weeds in wheat crops as well as its effects on wheat growth and yield components. It also highlights the management strategies which could minimize the inhibitory effect of weeds on wheat crops.

In Vitro Anti-Inflammatory Potential of Anaphyllum wightii Schott: An Endemic Plant of Southern Western Ghats

Inflammation is a protective mechanism offered by the body’s immune system after an injury, microbial infection, or any other physical or chemical damage. The role of cyclooxygenase and lipoxygenase enzymes in the inflammation process has been well established, and research works are focused on developing plant-based cyclooxygenase and lipoxygenase inhibitors that can provide potential anti-inflammatory drugs with no side effects. Even though there are previous reports suggesting the anti-inflammatory potential of the rhizome of the plant, no reports are available regarding the anti-inflammatory property of the leaves of Anaphyllum wightii. Hence the present study was intended to assess the anti-inflammatory activity of the leaves of Anaphyllum wightii and also to confirm the activity of rhizome in vitro. The anti-inflammatory action of the rhizome and the two morphological variants of leaves (broad and narrow leaves) of Anaphyllum wightii were determined by their inhibitory effects on cyclooxygenase and lipoxygenase enzymes. In the case of the cyclooxygenase inhibition assay, the narrow leaf extract showed the least IC50 value (43.182 µg/ml), whereas the broad leaf extract showed the least IC50 (38.174 µg/ml) for the lipoxygenase enzyme. Thus the present study revealed that the leaf extracts of Anaphyllum wightii exhibit significant anti-inflammatory potential compared to that of the rhizome extract. Hence the leaves may contain promising anti-inflammatory agents that may provide potential drugs for treating chronic inflammatory diseases. Also, this study could detect the presence of Ursolic acid, a potential anti-inflammatory agent, in Anaphyllum wightii through high resolution liquid chromatograph mass spectrometeric and high performance thin layer chromatographic analyses.

Effect Of Weed Management Practices On Weed Dynamics, Yield And Economics Of Spring Maize At Dhading Besi, Nepal

Weeds have been a major constraint in maize cultivation resulting in huge economic loss to farmers. A field experiment was conducted at Dhading Besi, Nepal to evaluate the effect of different weed management practices on weed dynamics, yield and economics of spring maize in 2020. The experiment was laid out in Randomized Complete Block Design (RCBD) comprising of eight treatments with three replications. Rajkumar hybrid maize variety was used in the experiment. The treatments consisted of weedy check, weed free, atrazine as PE @1.0 kg a.i./ha, pendimethalin as PE @1.0 kg a.i./ha, atrazine @ 1.0 kg a.i./ha as PE followed by (fb) 2,4-D EE @0.5 kg a.i./ha as PoE, pendimethalin @ 1.0 kg a.i./ha as PE fb 2,4-D EE @ 0.5 kg a.i./ha as PoE, 2 hand weeding @ 20 and 40 DAS and Farmer’s practice. The experiment result revealed that sequential application of atrazine fb 2,4-D EE treatment resulted in highest grain yield (11.37 t/ha) which was statistically similar with weed free (11.24 t/ha) and followed by the treatment atrazine (10.36 t/ha). 16 weed species belonging to 6 different families were identified. The broad leaf weeds and grassy weeds were more prominent than sedges. The total density and dry weight of weeds were found significantly lower in sequential application of atrazine fb 2,4-D EE than other treatments. Similarly, application of atrazine fb 2,4-D EE resulted in maximum weed control efficiency of 87.59 %, 95.91 % and 92.17% at 30, 45 and 60 DAS respectively. The lowest weed index (-1.27%) was also obtained in the application of atrazine fb 2,4-D EE. Yield loss due to weed in the weedy check treatment was found to be 50.99% followed by farmer’s practice (43.17%). The benefit cost ratio and increment in benefit over weedy check were highest in atrazine fb 2,4-D EE followed by atrazine and significantly better than other weed management treatments. The sequential application of atrazine fb 2,4- D EE was found to be the most effective in controlling weeds, high yielding and economical among the different weed control treatments. The application of atrazine one time as PE was found to be next better option for weed control in spring maize.

A study on plant preferences of red panda (Ailurus fulgens) in the wild habitat: foundation for the conservation of the species

The red panda is a lesser carnivore that has adapted to the herbivore diet and is distributed in the Himalayan and Hengduan mountain ranges. The study conducted on red panda in Singalila National Park recorded the highest encounter of the species within the altitude of 2800 to 3200 meters in the broad leaf deciduous and broad leaf coniferous forest. 22.22% of direct sightings of red pandas occurred on plant species belonging to the family Fagaceae and were followed by the family Ericaceae (18.52%). The plant species mostly preferred by the red panda in Singalila National Park were Lithocarpus pachyphyllus, Rhododendron arboreum, Abies densa, and Betulia utilis. During all seasons, the dominant plants found in the red panda pellets were Arundinaria maling and Arundinaria aristata.  The distribution of the red panda is influenced by the presence of the preferred plant species, therefore, through this studies effort has been made to document the plant species used by the red panda in the wild habitat.