Weed Residues Research Articles

Population dynamics of Alternaria solani, Cercospora beticola, Ramularia beticola, and Stemphylium beticola in residues of host crops, non-host crops, and weeds in Dutch rotation systems

Population dynamics of Alternaria solani, Cercospora beticola, Ramularia beticola, and Stemphylium beticola in residues of host crops, non-host crops, and weeds in Dutch rotation systems

Plant and soil characteristics affected by the allelopathic pathways of Avena fatua and Lolium temulentum weeds

The potential of the most prevalent weeds should be characterized biologically and chemically in infected soil and crops for sustainable agriculture. Therefore, the allelopathic potential of Avena fatua L. and Lolium temulentum L. weeds were compared via leachates, root exudates, decayed residues in soil, and the decomposition in water pathways. Chemical measurements were taken on wheat (Triticum aestivum L.), and soil decomposed solution. Based on EC50, the allelopathic effect of leachates were higher in aboveground parts than in subterranean parts, influenced by plant parts and concentrations. The root exudates show EC50 by 655.9 μg. ml−1 for A. fatua and 625.66 μg. ml−1 for L. temulentumin the seedling biomass fresh weights of T. aestivum. The systematic inhibition by decayed residues was affected by plant types, concentration, and time and correlated with soil parameters and crop performance. The decomposition rate was higher under aerobic conditions than anaerobic conditions, with the inhibition pattern showing the reverse trend. These finding highlight the importance of environmental conditions in mediating allelopathic effects. The highest quantities of phenolic acids determined by LC-ES/MS in decomposed solutions were citric acid, with concentrations of 7.71 and 13.31 μg/ml in A. fatua under aerobic conditions, and coumaric acid, with concentrations of 9.21 and 16.99 μg/ml in L. temulentum under aerobic conditions. The allelopathic potentials of A. fatua and L. temulentum may play a crucial role in T. aestivum crop growth and soil parameters. In general weed residues can suppress crop growth and negatively affect soil parameters based on their quantity and type, therefore they should be managed carefully for sustainable crop production.

Pyrolyzed and unpyrolyzed residues enhance maize yield under varying rates of application and fertilization regimes.

Biochar is increasingly gaining popularity due to its extensive recommendation as a potential solution for addressing the concerns of food security and climate change in agroecosystems, with biochar application for increased carbon sequestration, enhanced soil fertility, improved soil health, and increased crop yield and quality. There have been multiple studies on crop yield utilizing various biochar types and application amounts; however, none have focused on the influence of diverse biochar types at various pyrolysis temperatures with different application amounts and the integration of fertilizer regimes in maize crops. Therefore, a two-year factorial field experiment was designed in a temperate Himalayan region of India (THRI) to evaluate the residual effect of different biochar on maize yield under different pyrolysis temperatures, various application rates and fertilizer regimes. The study included three factors viz., amendment type (factor 1), rate of application (factor 2) and fertilizer regime (factor 3). Amendment type included 7 treatments: No biochar- control (A1), apple biochar @ 400°C pyrolysis temperature (A2), apple biochar @ 600°C pyrolysis temperature (A3), apple residue biomass (A4), dal weed biochar @ 400°C pyrolysis temperature (A5), dal weed biochar @ 600°C pyrolysis temperatures (A6), and dal weed residue biomass (A7). The rate of application included 3 levels: Low (L- 1 t ha-1), medium (M- 2 t ha-1), and high (H- 3 t ha-1). At the same time, the fertilizer regimes included 2 treatments: No fertilizer (N) and recommended dose of fertilizer (F). The results revealed that among the various amendment type, rate of application and fertilizer regimes, the A3 amendment, H rate of application and F fertilizer regime gave the best maize growth and productivity outcome. Results revealed that among the different pyrolyzed residues used, the A3 amendment had the highest plant height (293.87 cm), most kernels cob-1 (535.75), highest soil plant analysis development (SPAD) value (58.10), greatest cob length (27.36 cm), maximum cob girth (18.18 cm), highest grain cob yield (1.40 Mg ha-1), highest grain yield (4.78 Mg ha-1), higher test weight (305.42 gm), and highest stover yield (2.50 Mg ha-1). The maximum dry weight in maize and the number of cobs plant-1 were recorded with amendments A4 (14.11 Mg ha-1) and A6 (1.77), respectively. The comparatively 2nd year of biochar application than the 1st year, the H level of the rate of application than the L rate and the application and integration of the recommended dose of fertilizer in maize results in significantly higher values of growth and productivity in maize. Overall, these findings suggest that the apple biochar @ 600°C pyrolysis temperature (A3) at a high application rate with the addition of the recommended dose of fertilizer is the optimal biochar for enhancing the growth and productivity of maize in the THRI.

Soybean Response to Weed Residues in the Soil

Soybean Response to Weed Residues in the Soil

Mitigating Soil Erosion through Biomass-Derived Biochar: Exploring the Influence of Feedstock Types and Pyrolysis Temperature

Soil erosion is one of the major emerging threats to the Himalayan ecosystem. There is a dearth of diverse, cost-effective erosion control measures in the region. In the Himalayan region, where agriculture plays a pivotal role in local livelihoods and environmental stability, the management of soil erosion is of paramount importance. Hence, this study investigates the impact of biochar application on soil erosion and its related indices in the temperate Himalayas of India. This study employs a combination of physicochemical analysis and field experiments to assess the influence of biochar on soil erodibility. The research objectives include an examination of the influence of different temperature pyrolyzed biomasses and varying application rates on soil erodibility indices, viz., dispersion ratio (DR), percolation ratio (PR), clay ratio (CR), erosion ratio (ER), and mean weight diameter (MWD), considering two distinct fertilizer regimes. This study yielded quantitative results that shed light on the impact of various soil amendments and application rates on soil erodibility in the temperate Himalayas. Results showed that the mean values of the DR exhibited by amendment levels NB, AB400, AB600, RAC, DW400, DW600, and RDW were 0.37, 0.35, 0.51, 0.44, 0.51, 0.47, and 0.91, respectively. The mean values of DR for different amendment levels varied, with RDW exhibiting the highest erodibility at 0.91, while DW400 and DW600 demonstrated less soil disturbance, making them promising choices for soil erosion mitigation. Notably, the application of pyrolyzed weed residue improved soil erodibility, whereas AB600 resulted in increased soil erosion due to aggregate disintegration, as indicated by the MWD. Aquatic weed residues and apple wood chips applied without pyrolysis increased the soil erodibility, while pyrolyzed residues improved soil erodibility. The DR was 0.41 at the high application rate, 0.48 at the medium rate, and 0.61 at the low application rate. Among application rates, low rates (1 t ha−1) had the highest DR, followed by medium rates (2 t ha−1) and high rates (3 t ha−1). The no-fertilizer level exhibited higher DR (0.49) compared to the fertilized level (0.38). Results inferred that the application of AB400 °C at 3 t ha−1 can be adopted to minimize soil erosion and maintain ecological security in the temperate Himalayas.

Phenotypic and genotypic investigation of three weeds residues allelopathic effect on the growth of three hybrid wheat cultivars

The present study was carried out to determine the allelopathic effect of extraction of three herbs (Silybum marianum L. and Malva parviflora L. and Loliuim rigidum L. ) on three wheat cultivars (Rashid, Abo Ghrib and IPA99) on germination, growth and ear formation by classical research methods (laboratory and greenhouse experiments and molecular detection of GA3-oxase2 (TaGA3ox2-1) gene expression and its crucial role in wheat growth and Ta14S gene expression as a gene responsible for ear development. The study analyzed the influence of weed residues on the germination and growth of three wheat cultivars. According to the mean effect of aqueous weed extract on the cultivars, the laboratory experiments revealed a significant difference in all the characteristics studied. Keywords. Weeds, hybrid wheat cultivars, allelopathy, RT-PCR.

Isolation and Identification of Phenolic Compounds from the Plant Residues of Hordeum sp. and Brassica sp.by Using High Performance Liquid Chromatography (HPLC)

The current study included qualitative diagnosis and quantitative estimation of some active compounds in two types of weeds, namely wild mustard Hordeum sp. and wild barley Brassica sp. The results showed that these plants contained several chemical compounds that were diagnosed as phenolic acids. Wild mustard contained three chemical compounds, namely: Galic acid, Resorsenol, Vanillin While wild barley contained four compounds, namely: Galic acid, Resorsenol, Vanillin benzoic acid. The results of quantitative estimation also showed variation in the concentration of these compounds in the extracts of these weed residues.

Weed hosts and winter survival of Stemphylium vesicarium on onion in Ontario, Canada

Stemphylium leaf blight (SLB), caused by the fungal pathogen Stemphylium vesicarium, is an important disease of onion (Allium cepa). This pathogen also causes disease on a wide range of other plant species. SLB on onion is managed primarily through fungicide application. The source of primary inoculum and whether S. vesicarium can overwinter in the region were not known. Inoculation and subsequent re-isolation of the pathogen from common weed species present near onion fields demonstrated that many of these weedy species are hosts of S. vesicarium. Redroot pigweed (Amaranthus retroflexus), yellow nutsedge (Cyperus esculentus), yellow marshcress (Rorippa palustris), perennial sow thistle (Sonchus arvensis) and purslane (Portulaca oleracea) were identified as new hosts of S. vesicarium and bull thistle (Cirsium vulgare) was confirmed as a host. Sporulation on dead weed residue in spring may be a source of primary inoculum for infection of adjacent onion fields. Also, a study of pathogen survival in infected leaf pieces of onion buried in soil or left at the soil surface demonstrated that S. vesicarium can overwinter in infected onion leaf residue and produce pseudothecia and ascospores in early spring. These conclusions support existing management recommendations for the burial or removal of onion debris and managing weeds in and around onion fields.

Herbicidal Effects of Chenopodium murale and Coronopus didymus Sm. Residues Against Germination and Early Growth of Hordeum vulgare

This study reports the common problems of weed species that adversely affect the crop productivity of the agriculture crops at a large scale. The purpose of this study is to investigate the impact of dried application of Chenopodium murale and Coronopus didymus on seed germination and early growth of Hordeum vulgare. The experiment was performed in a randomised block design with three replications under the greenhouse condition in pot culture. Shoots and roots materials were separately dried in shade for 15–20 days, dry powdered shoot and root residues of C. murale and C. didymus were applied at 5 and 10g kg-1 doses to barley seeds in 6” pots with control for three weeks. C. didymus (10g) shoot residues were most inhibitive against germination (31.16%), GVI (0.85), SVI (4.90) and leaf area (3.94 cm2) of barley while 5 g root residues of the weed had least pronounced effect. Root length, shoot length, and dry biomass were most inhibited by C. murale 10 g in both shoot and root residue treatments. Shoot residues were more inhibitive of germination and growth than root residues of both weeds. Chlorophyll accumulation patterns showed mixed results with some treatments even stimulating their concentrations. Root treatments were in general more inhibitive than shoot treatments. All treated seedlings exhibited higher levels of proline accumulation compared to control. At lower dose, C. murale treatments were more inhibitive than C. didymus treatments. There is a great scope of research on these species to isolate and identify the active factors and also to understand their implication in the biocontrol of weeds apart from their potential negative effects on agricultural crops, especially cereal crops, which can be useful to increasing crop production in northern India, namely in Uttar Pradesh

Potential suppressive effects of Mexican poppy weed residues on germination and early growth of maize and pearl millet crops

Argemone ochroleuca allelochemical properties have been reported but not empirically tested on economically important staple cereal crops. Therefore, the objective of this study was to determine the potential Allelopathic effects of the alien weed’s residues on germination and early-growth of maize (Zea mays L.) and Pearl millet (Pennisertum glaucum). Allelopathic effects of A. ochroleuca on maize and millet seed germination were tested in a 2 (shoot and root) x 11 (0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100g/L water) factorial treatment arrangement in CRD in an incubator placed in a laboratory. Whereas effects of the weed extracts on the same crops’ early-growth were tested in a 2 (shoot and roots) x 8 (0, 2, 4, 6, 8, 10, 12 and 14g ground-powdered extracts) factorial arrangement in RCBD under laboratory conditions. Maize and millet germination percentage, germination speed, mean germination time, mean daily germination, plumule and radicle length were measured for germination test, whereas, plant height, stem diameter, root and shoot mass were used as indicators of A. ochroleuca suppression of early plant growth. Relative to untreated control, concentration equal to and greater than 10g/L aqueous extracts of A. ochroleuca reduced millet and maize seed germination variables by 10–100% and 28–56%, respectively, while early-growth variables were reduced by 66–100% and 4–37%, respectively. Argemone ochroleuca shoot extracts were more suppressive than root extracts on germination and early growth of the two crops. In conclusion, A. ochroleuca Allelopathic effects were concentration and plant-part dependent, inhibitory effects increased with concentrations, with extracts from shoots being more Allelopathic on measured variables when compared to root extracts. As A. ochroleuca continues to spread yearly without any control strategies in place, a threat exist on maize and Pearl millet production especially in communal farming areas where improved management strategies are non- existent. Key words: Allelopathic, Argemone ochroleuca, germination, growth, millet, maize, plumule, radicle

Effects of leaf residues from Ageratina adenophora on germination, growth and productivity of two rabi crops

Ageratina adenophora is among the most appalling invasive alien weeds spreading over the majority of habitats in tropical and sub-tropical countries. Agricultural lands are one of the major invaded areas by this weed and its luxuriant growth has been reported along the croplands. To lessen the harmful impacts posed by this weed, farmers and land managers usually slash the aerial parts of this weed. But the piled residues are not treated and are left which could have the impacts on the crops growing in its vicinity. In this study, impacts of fresh, dry and composted leaf tissues of A. adenophora in pot experiment against two food crops viz. Triticum aestivum (wheat, commonly known as gehu) and Lens culinaris (lentil, commonly known as masoor) were investigated. Five concentration treatments i.e. C0 (control-0 g leaves/kg soil)), C1 (10g leaves/kg soil), C2 (20g leaves/kg soil), C3 (40g leaves/kg soil) and C4 (80g leaves/kg soil) were prepared and the effects on germination, growth (shoot and root), dry matter accumulation and yield of test plant species were recorded. Fresh and dry leaf treatments inhibited the performance of lentil as well as wheat while the composted leaves promoted seed germination, plant height, biomass and crop yield in concentration dependent manner. As compared to fresh and composted leaves, test crops were severely affected by dry leaf treatments and failed to produce pods and seeds towards higher concentrations. The results revealed that fresh and dry leaves of A. adenophora have inhibitory effect on germination and growth of test plants while composting of A. adenophora leaves reduced the inhibitory effect of weed residues incorporated into the soil.

Aggregate distribution and substrate-induced respiration under different tillage and mulching management systems in organic farming

ABSTRACT In organic farming, intensive tillage for weed eliminating may cause physical and biological soil degradation. Weed residue mulch can be used to stabilize the organic carbon in the soil by improving soil aggregation and increasing microbial activity. However, the effectiveness of weed mulch in no-tillage (NT) and conventional tillage (CT) systems remains unclear. Therefore, we studied the influence of clipped weed mulch (CM) and no mulch (NM), in combination with NT and CT on the water-stable aggregates, and carbon stabilization in different-sized soil aggregates as well as on substrate-induced respiration (SIR) and the fungal-to-bacterial activity ratio at a soil depth of 0–5 cm. Macroaggregates (>4 mm water- stable aggregates) were 46.8% higher in NT than in CT in June and October 2014 and 52.4% higher with NT in 2015. Microaggregates (0.5- and 0.25-mm aggregates) were higher in CT than NT in both years. The use of CM also increased water-stable aggregates in both years. In 2014, >4-mm aggregate fraction was 6.5% higher with CM than with NM. In 2015, the same parameters were even more effective, with >4-mm and 2-mm aggregate fractions were 23.9% and 34.9% higher with CM respectively. MWD was higher in NT than in CT in both years and CM had slightly increased (but not significantly) this in October. In both years, soil organic carbon (SOC) and nitrogen were significantly higher in NT than in CT, and in October CM further increased these in both tillage systems. In both tillage systems, the highest amounts of SOC was measured in >4-mm aggregate fraction than microaggregates. In both years, microbial SIR was higher in NT than in CT. Further, research is needed to find out long term effect of weed residue mulch in these changes in both tillage systems.

Phytotoxicity of above - ground weed residue against some crops and weeds

Phytotoxicity of above - ground weed residue against some crops and weeds

Investigation into the overwintering and winter-management of the common pistachio psyllid, Agonoscena pistaciae (Hemiptera: aphalaridae), a major pest in pistachio plantations

ABSTRACTOverwintering sites and winter-management of the common pistachio psyllid, Agonoscena pistaciae Burckhardt & Lauterer, a serious pest of the cultivated pistachio Pistacia vera Linnaeus, were surveyed in pistachio orchards in Rafsanjan, south Iran, through 2010 and 2012. Agonoscena pistaciae overwinters within orchards, preferentially concealed under organic material on the ground. Plant litter, including old pistachio leaves and weed residue such as dead grass, supported the greatest numbers of adult psyllids during the late autumn through early spring. Emergence began in late February and lasted for about 50 days. The number of psyllids that emerged from fallen dead leaves mixed with weed residue was about 15 times greater than the number of psyllids that emerged from bare ground. This result verified the suggestion that A. pistaciae might be controlled whilst overwintering. Winter ploughing of the orchard floor caused a significant reduction in the density of the psyllid population. Orchard sani...

ACCUMULATION POTENTIAL AND NUTRIENT CYCLING OF APPLE OF PERU (Nicandra physalodes)

ABSTRACT Weed residues can influence nutrient cycling in agroecosystems. Quantifying this potential nutrient source may influence weed control and fertilisation practices. Nicandra physalodes (L.) Gaertn. is a weed with a short life cycle and a great ability to accumulate dry matter. Field observations suggest that N. physaloides residues are easily decomposed in soil. The objective of this study was to evaluate the effect of increasing of N, P and K doses on the growth of N. physalodes, as well as the nutrient content, chemical characteristics and C/N ratio of the weed. A randomised block design, arranged in split-plot with three replications, was utilised. The main plots were given four doses of NPK (Dose 1 - 0, 0.3 and 17.2 mg dm-3; Dose 2 - 30, 450.3 and 75.4 mg dm-3; Dose 3 - 60, 900.3 and 133.4 mg dm-3; and Dose 4 - 120, 1800.3 and 249.68 mg dm-3), and the subplots were harvested at ten time points after emergence (26, 33, 40, 47, 54, 61, 76, 91, 106 and 121 days). Higher dry matter production and N, P and K content were observed in plants grown on higher levels of fertiliser. The increase of N, P and K levels in the soil resulted in greater total accumulation of these macronutrients. The highest macronutrient contents were K and N. The treatments did not affect neutral detergent fibre (NDF), acid detergent fibre (ADF) and C/N ratio of plant. N. physalodes had low C/N ratio, low NDF and ADF levels, and great nutrient accumulation, suggesting that this plant is quickly decomposed, providing a rapid cycling of nutrients.

Suppression of Maize (Zea mays) Seedling Growth by Invasive Alligatorweed (Alternanthera philoxeroides) Residues

ABSTRACT: To investigate the allelopathic influence of soil incorporated plant residues of alligatorweed on emergence and seedling growth of maize (Zea mays), an experiment was conducted under laboratory conditions in the 2014-15 period. The effect of soil amended with whole plant residues of alligatorweed at different concentrations (1, 2, 3, 4 and 5% on w/w basis) was compared with residue free soil (control). Emergence traits, such as emergence percentage, time to 50% emergence, mean emergence time and emergence index were negatively influenced by weed residue incorporation as compared with weed residue free soil. Alligatorweed residues also exerted a pronounced negative influence on root and shoot lengths, root and shoot dry weights and seedling vigor index of the maize crop. The results revealed that the inhibitory effect was directly proportional to the increasing concentrations (1, 2, 3, 4 and 5%) of the weed residues as compared to control treatment. It was observed that soil infested with 4% and 5% residues of alligatorweed caused a maximum reduction in emergence (76-87%), root and shoot lengths (58-73% and 42-61%), root and shoot dry weights (49-58% and 40-48%) and seedling vigor index (87-95%) of the maize crop. Chlorogenic acid, ferulic acid, 4-hydroxy-3-methoxybenzoic acid, trans-4-hydroxy 3-methoxy cinnamic acid, gallic acid, p-coumaric acid, querceitin and syringic acid were identified as water soluble phenolics in alligatorweed residue soil saturated solution. This study indicates that the allelopathic potential of alligatorweed may play an important role in suppressing maize seedling growth.

Allelopathic Effect of Some Associated Weeds of Wheat on Germinability and Biomass Production of Wheat Seedlings

ABSTRACT: Weeds associated with crops may impose their phytotoxic effects on crop plants through the release of their allelochemicals and hence seriously reduce crop productivity. The present study was conducted to investigate the allelopathic effect of water soluble phenolics of weeds associated with wheat crop (Vicia sativa, Trigonella polycerata, Lathyrus aphaca, Medicago polymorpha, Melilotus indica) on germinability and biomass production of wheat seedlings by using their water extracts at 2.5% (w/v) and 5% (w/v) concentrations and residues of the same weeds with 0, 15 and 30 d decomposition periods at 2% (w/w) concentration. The results showed that the water extracts of M. indica and V. sativa at 5% concentration imposed the most inhibitory effect on energy of germination (81%) and prolonged time to 50% germination (226%), respectively; by contrast, T. polycerata and M. indica extracts at the same concentration inhibited shoot (8%) and root fresh biomass (64%). However, shoot dry biomass was exalted by the weed extracts at both concentrations with maximum increase (29%) caused by the M.indica extract at 2.5% concentration; however, root dry biomass (46%) and root/shoot ratio (51%) were decreased by M. polymorpha and M. indica extracts at 5% concentration, respectively. Residues of L. aphaca and M. polymorpha with a 30 d decomposition period proved the most toxic regarding energy of emergence (85%) and time to 50% emergence (138%), respectively; while, shoot fresh (41%) and dry biomass (26%) production were hindered mostly by M. indica and M. polymorpha residues with a 30 d decomposition period. There was the highest decrease in root fresh (64%) and dry biomass (64%), and root/shoot ratio (64%) when treatment was performed with V. sativa residues without decomposition. The results show that leachates and residues of weeds inhibit wheat germinability and biomass production through release of allelochemicals, and they are a threat to profitable crop production.

Relative phytotoxicity of parthenium weed (Parthenium hysterophorus L.) residues on the seedling growth of a range of Australian native and introduced species

The invasive herbaceous species Parthenium hysterophorus L. (Asteraceae), commonly known as parthenium weed has rapidly become a significant weed in more than 30 countries. Parthenium weed litter taken from the introduced biotypes was relatively more phytotoxic than that taken from biotypes coming from the native range when tested on lettuce and this may indicate one reason for invasion success. However, no significant difference was observed in phytotoxicity to lettuce seedling growth when two Australian biotypes of parthenium weed were compared, one invasive and one non-invasive, indicating that invasiveness was not associated with litter phytotoxicity in all cases. Residue from the invasive parthenium weed biotype had a greater phytotoxic effect upon Australian native pasture grass species relative to the introduced pasture grass species with buffel grass (Cenchrus ciliaris L.) and bull Mitchell grass (Astreble sequarrosa C.E.Hubb) showing the greatest tolerance to parthenium weed phytochemicals. When compared with residue taken from plants that has a range of phytotoxic capacity, parthenium weed residue was considered to be only moderately phytotoxic suggesting that the phytotoxicity of its residue may not be the main reason for the plants invasive trait.

ALLELOPATHIC INFLUENCE OF SOME WEED RESIDUES ON GROWTH AND DEVELOPMENTAL CHANGES OF GREEN GRAM (VIGNA RADIATA (L.) WILCZEK)

The term allelopathy refers to the detrimental effects of higher plants of one species (the donor) on the germination, growth, or development of another species (the recipient). In the present studyallelopathic influence of weed species, Echinochloa colona (L.) Link, (Poaceae), Cleome viscosa L. (Capparidaceae) and Ammania baccifera L. (Lythraceae) on green gram (Vigna radiata (L.) Wilczek were investigated. The individual and combined residues of three weeds wereincorporated to the soil at the quantities of 0,1,2,3 and 4% (w/w) in the plots and the germination, seedling growth dry weight of green gram were assessed. The results showed that all the concentrations of combined weed residues exhibited higher degree of inhibitory effects than the individual weed residues in all the parameters employed in the study except at 1% of C. dactylon, where insignificant growth promotion observed. The percentage of inhibitory effects of weedresidues increases with increasing the magnitude of the residues. The degree of reduction percentage of all the growth parameters was concentration dependent.Among the three weeds, A. baccifera had more retarding effects on the growth of green gram and the order of inhibitory effect of three weed was A.baccifera, C. viscosa and E. colona.

ALLELOPATHIC INFLUENCE OF TRIANTHIMA PORTULACASTRUM L. ON GROWTH AND DEVELOPMENTAL RESPONSES OF SESAME (SESAMUM INDICUM L.)

An experiment was conducted in order to determine the allelopathic effects of the aqueous extract of Trianthima portulacastrum L.on the seed germination, seedling growth and chlorophyll content ofsesame (Sesamum indicum L.). Greenhouse experiment was carried out as RCBD (Randomized complete block design)with four replications. Treatments included 0, 1, 2, 3 and 4% (W/W) residues of whole plant of T.portulacastrum with normal field soil. Results showed that the low concentrations of T.portulacastrum had no significant effect on the germination percentage, seedling length, dry weight, total chlorophyll contents at lower concentration(1%) of weed residues. However, treatments with higher concentrations had negative effects on germination, growth and seedling dry weight of sesame.