Fresh water, coupled with soil salinization in many areas has resulted in an increased need forscreening of salt tolerant turf grasses. Relative salinity tolerance of eightwarm season turfgrass species were examined in this study in sand culture. Grasses were grown in a glasshouse, irrigated with either distilled water or saline sea water adjusted to 24, 48 or 72 dSm-1. Salt tolerances of the grasses were assessed on the basis of their shoot and root growth, leaf firing and turf quality. Regression analysis indicated that Zoysiajaponica (Japanese lawn grass) (JG), Stenotaphrum secundatum (St. Augustine) (SA), Cynodon dactylon (satiri) (BS), Zoysia teneuifolia (Korean grass) (KG), Digitaria didactyla (Serangoon grass) (SG), Cynodon dactylon (Tifdwarf) (TD), Paspalum notatum (Bahia grass) (BG) and Axonopus compressus(Pearl blue) (PB) suffered a 50% shoot growth reduction at 36.0, 31.8, 30.9, 28.4, 26.4, 25.7, 20.0 and 18.6 dSm1 of salinity, respectively and a root growth reduction at44.9, 43.7, 33.4, 31.0, 29.5 27.5, 21.5 and 21.4 dSm- of salinity, respectively. Leaf firing and turf quality of the selected species, as a whole, were also found to be affected harmoniously with the change in root and shoot growth. On the basis of the experimental results the selected species were ranked for salinity tolerance as JG>SA>BS>KG>SG >TD>BG>PB.
Clinacanthus nutans Lindau is known as snake grass belonging to the Acanthaceae family. This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes, insects and snake bites, lesions caused by herpes simplex virus, diabetes, and gout in Malaysia, Indonesia, Thailand and China. Phytochemical investigations documented the varied contents of bioactive compounds from this plant namely flavonoids, glycosides, glycoglycerolipids, cerebrosides and monoacylmonogalatosylglycerol. The pharmacological experiment proved that various types of extracts and pure compounds from this species exhibited a broad range of biological properties such as anti-inflammatory, antiviral, antioxidant, and anti-diabetic activities. The findings of toxicity study showed that extracts from this plant did not show any toxicity thus it can be used as strong therapeutic agents for specific diseased conditions. However, further experiments on chemical components and their mode of action showing biological activities are required to elucidate the complete phytochemical profile and assess to confirm their suitability for future drugs. This review summarizes the medicinal uses, phytochemistry and pharmacology of this plant in order to explore its therapeutic potential and gaps necessitating for prospected research work.
Sweet potato (Ipomoea batatas L.) is one of the most important consumed crops in many parts of the world because of its economic importance and content of health-promoting phytochemicals.
Rice has been subjected to a great deal of stress during its brief existence, but it nevertheless ranked first among cereal crops in terms of demand and productivity. Weeds are characterized as one of the major biotic stresses by many researchers. This research aims to determine the most potential allelopathic rice variety among selected rice accessions. For obtaining preeminent varieties, seventeen rice genotypes were collected from Bangladesh and Malaysia. Two prevalent procedures, relay seeding and the sandwich technique were employed to screen the seventeen rice (donor) accessions against barnyard grass (tested plant). In both approaches, only the BR17 variety demonstrated substantial inhibition of germination percentage, root length, and dry matter of barnyard grass. The rice variety BR17 exclusively took the zenith position, and it inhibited the development of barnyard grass by more than 40-41% on an average. BR17 is originated from KN-1B-361-1-8-6-10 (Indonesia) and developed by the Bangladesh Rice Research Institute (BRRI), Gazipur, Bangladesh in 1985, having a high yielding capacity of more than 6 t/ha. Our study suggested that the usage of the allelopathy-weed inverse relationship to treat the weed problem can be a fantastic choice in the twenty-first century.
This study was undertaken to determine the effects of varied salinity regimes on the morphological traits (plant height, number of leaves, number of flowers, fresh and dry weight) and major mineral composition of 13 selected purslane accessions. Most of the morphological traits measured were reduced at varied salinity levels (0.0, 8, 16, 24 and 32 dS m(-1)), but plant height was found to increase in Ac1 at 16 dS m(-1) salinity, and Ac13 was the most affected accession. The highest reductions in the number of leaves and number of flowers were recorded in Ac13 at 32 dS m(-1) salinity compared to the control. The highest fresh and dry weight reductions were noted in Ac8 and Ac6, respectively, at 32 dS m(-1) salinity, whereas the highest increase in both fresh and dry weight was recorded in Ac9 at 24 dS m(-1) salinity compared to the control. In contrast, at lower salinity levels, all of the measured mineral levels were found to increase and later decrease with increasing salinity, but the performance of different accessions was different depending on the salinity level. A dendrogram was also constructed by UPGMA based on the morphological traits and mineral compositions, in which the 13 accessions were grouped into 5 clusters, indicating greater diversity among them. A three-dimensional principal component analysis also confirmed the output of grouping from cluster analysis.
Substantial quantities of pesticides are routinely applied to enhance agricultural crop production. Pesticides used in this way continuously accumulate in the environment and in foods. Harvested crops contain pesticide residues at various concentrations, with potential harmful impacts on human health. Hence, it is of value to identify techniques for the effective decontamination of tainted foods. However, cleaning with water or household agents, e.g., acetic acid and sodium bicarbonate, are recognized treatments for the efficient degradation of pesticides from vegetables and fruits. There is an apparent void of information about the decontamination treatments for raw fishes using household agents that are affordable for all classes of consumers. Hence, the present study was performed to determine the most efficient household technique for reducing pesticide residue levels from precooked raw fish to ensure the utmost food safety. Fish muscles of four species of fishes, viz., Clarias gariepinus, Channa striatus, Anabas testudineus and Trichogaster trichopterus, were treated with six treatments: washing with running tap water (T1), dipping in normal water (T2), dipping in 2% salt solution (T3), dipping in 2% vinegar (T4), dipping in 0.1% sodium bicarbonate solution (T5) as well as dipping in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice (T6), as fish muscle is the major consumable portion of fish. The current study demonstrated that the removal percentage of lindane, heptachlor, aldrin, endosulfan, dieldrin, endrin, DDT, methoxychlor and cypermethrin residues against the treated household treatments, in downward order, were soaking in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice solution (T6) > soaking in 2% vinegar (T4) solution > soaking in 0.1% sodium bicarbonate (T5) solution > soaking in 2% salt (T3) solution > washing with running tap water (T1) > soaking in stable normal water (T2). The treatment of raw fish muscle samples by soaking them in 0.1% sodium bicarbonate solution + 2% vinegar + 2% salt solution + lemon juice was found to be the most efficient household treatment, performing significant reductions (%) in pesticide concentration: 72−80% (p < 0.05) in Channa striata, 71−79% (p < 0.05) in Clarias gariepinus, 74−80% (p < 0.05) in Anabas testudineus as well as 78−81% (p < 0.05) in Trichogaster trichopterus before cooking.
Till now, herbicide seems to be a cost effective tool from an agronomic view point to control weeds. But long term efficacy and sustainability issues are the driving forces behind the reconsideration of herbicide dependent weed management strategy in rice. This demands reappearance of physical and cultural management options combined with judicious herbicide application in a more comprehensive and integrated way. Keeping those in mind, some agronomic tools along with different manual weeding and herbicides combinations were evaluated for their weed control efficacy in rice under aerobic soil conditions. Combination of competitive variety, higher seeding rate, and seed priming resulted in more competitive cropping system in favor of rice, which was reflected in lower weed pressure, higher weed control efficiency, and better yield. Most of the herbicides exhibited excellent weed control efficiency. Treatments comprising only herbicides required less cost involvement but produced higher net benefit. On the contrary, treatments comprising both herbicide and manual weeding required high cost involvement and thus produced lower net benefit. Therefore, adoption of competitive rice variety, higher seed rate, and seed priming along with spraying different early-postemergence herbicides in rotation at 10 days after seeding (DAS) followed by a manual weeding at 30 DAS may be recommended from sustainability view point.
Submergence or flood is one of the major harmful abiotic stresses in the low-lying countries and crop losses due to waterlogging are considerably high. Plant breeding techniques, conventional or genetic engineering, might be an effective and economic way of developing crops to grow successfully in waterlogged condition. Marker assisted selection (MAS) is a new and more effective approach which can identify genomic regions of crops under stress, which could not be done previously. The discovery of comprehensive molecular linkage maps enables us to do the pyramiding of desirable traits to improve in submergence tolerance through MAS. However, because of genetic and environmental interaction, too many genes encoding a trait, and using undesirable populations the mapping of QTL was hampered to ensure proper growth and yield under waterlogged conditions Steady advances in the field of genomics and proteomics over the years will be helpful to increase the breeding programs which will help to accomplish a significant progress in the field crop variety development and also improvement in near future. Waterlogging response of soybean and major cereal crops, as rice, wheat, barley, and maize and discovery of QTL related with tolerance of waterlogging, development of resistant variety, and, in addition, future prospects have also been discussed.
Pesticides such as endosulfan, heptachlor and dieldrin persist in aquatic environments as a result of their resistance to biodegradation. However, there is no adequate information about the toxicity of endosulfan, heptachlor and dieldrin to the aquatic organism, African catfish (Clarias gariepinus)-a high valued widely distributed commercially interesting species. The current experiment was performed with the aim to determine the median lethal concentration (LC50) of endosulfan, heptachlor and dieldrin to African catfish (Clarias gariepinus); their behavioral abnormalities and histopathological alterations in several vital organs. A total of 324 juvenile fish were exposed for 96 h to six concentrations of endosulfan and dieldrin at 0, 0.001, 0.002, 0.004, 0.008 and 0.016 ppm, and to heptachlor at concentrations of 0, 0.02, 0.04, 0.08, 0.16 and 0.32 ppm for dose-response tests. The study demonstrated that the species is highly susceptible to those contaminants showing a number of behavioral abnormalities and histopathological changes in gill, liver and muscle. The 96-h LC50 value of endosulfan, dieldrin and heptachlor for the African catfish was found as 0.004 (0.001-0.01) mg/L, 0.006 mg/L and 0.056 (0.006-0.144) mg/L, respectively. Abnormal behaviors such as erratic jerky swimming, frequent surfacing movement with gulping of air, secretion of mucus on the body and gills were observed in response to the increasing exposure concentrations. Histopathological alterations of liver, gill and muscle tissues were demonstrated as vacuolization in hepatocytes, congestion of red blood cells (RBCs) in hepatic portal vein; deformed secondary lamellae and disintegrated myotomes with disintegrated epidermis, respectively. These findings are important to monitor and responsibly manage pesticide use in and around C. gariepinus aquacultural areas.
The allelopathic effect of various concentrations (0, 6.25, 12.5, 50 and 100 g L-1) of Parthenium hysterophorus methanol extract on Cyperus iria was investigated under laboratory and glasshouse conditions. No seed germination was recorded in the laboratory when P. hysterophorus extract was applied at 50 g L-1. In the glasshouse, C. iria was mostly injured by P. hysterophorus extract at 100 g L-1. The phytochemical constituents of the methanol extract of P. hysterophorus were analyzed by LC-ESI-QTOF-MS=MS. The results indicated the presence of phenolic compounds, terpenoids, alkaloids, amino acids, fatty acids, piperazines, benzofuran, indole, amines, azoles, sulfonic acid and other unknown compounds in P. hysterophorus methanol extract. A comparative study was also conducted between P. hysterophorus extract (20, 40 and 80 g L-1) with a synthetic herbicide (glyphosate and glufosinate ammonium at 2 L ha-1) as a positive control and no treatment (negative control) on Ageratumconyzoides, Oryzasativa and C. iria. The growth and biomass of test weeds were remarkably inhibited by P. hysterophorus extract. Nevertheless, no significant difference was obtained when P. hysterophorus extract (80 g L-1) and synthetic herbicides (glyphosate and glufosinate ammonium) were applied on A.conyzoides.
The current study was designed to investigate the effect of Parthenium hysterophorus L. methanol extract on Ageratum conyzoides L., Oryza sativa f. spontanea (weedy rice) and Cyperus iria L. in glasshouse condition. Here, Parthenium hysterophorus methanol extract at 20, 40, and 60 g L-1 concentrations was applied on the test species to examine their physiological and biochemical responses at 6, 24, 48 and 72 h after spraying (HAS). The phytotoxicity of P. hysterophorus was strong on A. conyzoides compared to weedy rice and Cyperus iria at different concentrations and exposure times. There was a reduction in photosynthesis rate, stomatal conductance, transpiration, chlorophyll content and carotenoid content when plants were treated with P. hysterophorus extract concentrations. Exposure to P. hysterophorus (60 g L-1) at 24 HAS increased malondialdehyde (MDA) and proline content by 152% and 130%, respectively, in A. conyzoides compared with control. The activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD)) were also increased in the presence of P. hysterophorus extract. Present findings confirm that the methanol extract of P. hysterophorus can disrupt the physiological and biochemical mechanism of target weeds and could be used as an alternative to chemical herbicides.
Herbicides made from natural molecules are cost-effective and environmentally friendly alternatives to synthetic chemical herbicides for controlling weeds in the crop field. In this context, an investigation was carried out to ascertain the allelopathic potential of Parthenium hysterophorus L. as well as to identify its phenolic components which are responsible for the allelopathic effect. During the observation, the rate of germination and seedlings' growth of Vigna subterranea (L.) Verdc, Raphanus sativus (L.) Domin, Cucurbita maxima Duchesne., Cucumis sativus L., Solanum lycopersicum L., Capsicum frutescens L., Zea mays L., Abelmoschus esculentus (L.) Moench, Daucus carota L., Digitaria sanguinalis (L.) Scop and Eleusine indica (L.) Gaertn were investigated by using methanol extracts, isolated from leaf, stem and flower of P. hysterophorus. Six concentrations (i.e., 25, 50, 75, 100, and 150 g L-1) of methanol extracts were isolated from P. hysterophorus leaf, stem and flower were compared to the control (distilled water). It was also observed that the concentration of methanol extracts (isolated from P. hysterophorus leaf, stem, and flower) while increased, the rate of seed germination and seedling growth of both selected crops and weeds decreased drastically, indicating that these methanol extracts have allelopathic potential. The allelopathic potential of P. hysterophorus leaf extraction (811) was found higher than the extraction of the stem (1554) and flower (1109), which is confirmed by EC50 values. The principal component analysis (PCA) was also used to re-validate the allelopathic potentiality of these methanol extracts and confirmed that Raphanus sativus, Solanum lycopersicum, Capsicum frutescens, Abelmoschus esculentus, Daucus carota, Digitaria sanguinalis, and Eleusine indica were highly susceptible to allelochemicals of P. hysterophorus. Besides these, the LC-MS analysis also revealed that the P. hysterophorus leaf extract contained 7 phenolic compounds which were responsible for the inhibition of tested crops and weeds through allelopathic effect. The results of the current study revealed that the leaf of P. hysterophorus is a major source of allelopathic potential on crops and weeds and which could be used as a valuable natural herbicide in the future for the sustainability of crop production through controlling weeds.
The methanolic extracts of 13 accessions of purslane were analyzed for their total phenol content (TPC), total flavonoid contents (TFC), and total carotenoid contents (TCC) and antioxidant activity of extracts was screened using FRAP assay and DPPH radical scavenging methods. The TPC, TFC, and TCC ranged from 0.96 ± 0.04 to 9.12 ± 0.29 mg GAE/g DW, 0.13 ± 0.04 to 1.44 ± 0.08 mg RE/g DW, and 0.52 ± 0.06 to 5.64 ± 0.09 mg (β-carotene equivalent) BCE/g DW, respectively. The DPPH scavenging (IC50) activity varied between 2.52 ± 0.03 mg/mL and 3.29 ± 0.01 mg/mL and FRAP ranged from 7.39 ± 0.08 to 104.2 ± 6.34 μmol TE/g DW. Among all the measured micro- and macrominerals K content was the highest followed by N, Na, Ca, Mg, P, Fe, Zn, and Mn. The overall findings proved that ornamental purslane was richer in antioxidant properties, whereas common purslane possesses more mineral contents than ornamental ones.
This current investigation was undertaken both in laboratory and glasshouse for documentation and quantification of phytochemicals from different parts of the parthenium (Parthenium hysterophorus L.) plant through LC-MS and HPLC to study their effect on two crops namely, Bambara groundnut (Vigna subterranean L.) and maize (Zea mays L.), and six different types of weed e.g., Digitaria sanguinalis, Eleusine indica, Ageratum conyzoides, Cyperus iria, Euphorbia hirta, and Cyperus difformis. The parthenium methanolic leaf extracts at 25, 50, 75, and 100 g L-1 were sprayed in the test crops and weeds to assess their physiological and biochemical reactions after 6, 24, 48, and 72 h of spraying these compounds (HAS). The LC-MS analysis confirmed seven types of phytochemicals (caffeic acid, ferulic acid, vanillic acid, parthenin, chlorogenic acid, quinic acid, and p-anisic acid) in the parthenium leaf extract that were responsible for the inhibition of tested crops and weeds. From the HPLC analysis, higher amounts in leaf methanol extracts (40,752.52 ppm) than those of the stem (2664.09 ppm) and flower extracts (30,454.33 ppm) were recorded. Parthenium leaf extract at 100 g L-1 had observed higher phytotoxicity on all weed species except C. difformis. However, all crops were found safe under this dose of extraction. Although both crops were also affected to some extent, they could recover from the stress after a few days. The photosynthetic rate, transpiration rate, stomatal conductance, carotenoid and chlorophyll content were decreased due to the application of parthenium leaf extract. However, when parthenium leaf extract was applied at 100 g L-1 for 72 h, the malondialdehyde (MDA) and proline content were increased in all weeds. Enzymatic antioxidant activity (e.g., superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) contents) were also elevated as a result of the sprayed parthenium leaf extract. The negative impact of physiological and biochemical responses as a consequence of the parthenium leaf extract led the weed species to be stressed and finally killed. The current findings show the feasibility of developing bioherbicide from the methanolic extract of parthenium leaf for controlling weeds, which will be cost-effective, sustainable, and environment friendly for crop production during the future changing climate.