Water and air temperature impacts on rice (<Emphasis Type="Italic">Oryza sativa</Emphasis>) phenology

Air temperature (T_a) is commonly used for modeling rice phenology. However, since the growing point of rice is under water during the vegetative and the early part of the reproductive period, water temperature (T_w) is likely to have a greater influence on crop developmental rates than T_a during this period. To test this hypothesis, we monitored T_w, T_a, and crop phenology in three commercial irrigated rice fields in California, USA. Sampling locations were set up on along a transect from the water inlet into the field. (Water warms up as it moves into the field.) T_a averaged 22.7 °C across sampling locations within each field, but average seasonal T_w increased from 22 °C near the inlet to 23.4 °C furthest away from the inlet. Relative to T_w furthest from the inlet, low T_w near the inlet delayed time to panicle initiation (PI 5 days) and heading (HD 8 days) and the appearance of one yellow hull on the main stem panicle (R7 9 days). Using T_w instead of T_a when the active growing point is under water until booting (midway between PI and HD) in a thermal time model improved accuracy (root-mean-square error, RMSE) for predicting time to PI by 2.5 days and HD by 1.6 days and R7 by 1.8 days. This model was further validated under more typical field conditions (i.e., not close to cold water inlets) in six locations in California. Under these conditions, average T_w was 2.6 °C higher than T_a between planting and booting, primarily due to higher daily maximum T_w values. Using T_w in the model until booting improved RMSE by 1.2 days in predicting time to HD. Using T_w instead of T_a during this period could improve the accuracy of rice phenology models.     

Short-term daily forecasting of crop evapotranspiration of rice using public weather forecasts

Accurate forecasts of daily crop evapotranspiration (ET_c) are essential for real-time irrigation management and water resource allocation. This paper presents a method for the short-term forecasting of ET_c using a single-crop coefficient approach and public weather forecasts. Temperature forecasts with a 7-day lead time in 2013–2015 were retrieved and entered into a calibrated Hargreaves–Samani model to compute daily reference evapotranspiration (ET₀) forecasts, while crop coefficient (K_c) empirical values were estimated from both observed ET_c value and calculated ET₀ values using the Penman–Monteith equation for the period of 2010–2012. Daily ET_c forecasts of irrigated double-cropping rice were determined for three growing seasons during the period of 2013–2015 and were compared with ET_c values measured by the weighing lysimeters at the Jiangxi experimental irrigation station in southeastern China. During the early rice season, the average mean absolute error (MAE) and root-mean-square-error (RMSE) values of ET_c forecasts ranged from 0.95 to 1.06 mm day^?1 and from 1.18 to 1.31 mm day^?1, respectively, and the average correlation coefficient (R) ranged from 0.39 to 0.54; for late rice, the average MAE and RMSE values ranged from 1.01 to 1.09 mm day^?1 and from 1.32 to 1.40 mm day^?1, respectively, and the average R value ranged from 0.54 to 0.58. There could be three factors responsible for errors in ET_c forecasts, including temperature forecast errors, K_c value errors and neglected meteorological variables in the HS model, including wind speed and relative humidity. In addition, ET_c was more sensitive to changes in temperature than K_c. The overall results indicated that it is appropriate to forecast ET_c with the proposed model for real-time irrigation management and water resource allocation.     

Validation of dual-crop coefficient method for calculation of rice evapotranspiration under drying–wetting cycle condition

Based on data collected from rice fields under drying–wetting cycle condition, the procedure of dual-crop coefficient (K _cd) approaches was calibrated and validated to reveal its feasibility and improve its performance in rice evapotranspiration (ET _c) estimation. It was found that K _cd based on FAO-recommended basal crop coefficients (K _cb) underestimated dual-crop coefficients in monsoon climate region in East China. The recommended coefficient (K _cp) value of 1.2 was not high enough to reflect the pulse increase of rice ET _c after soil wetting. The K _cb values were calibrated as 1.52 and 0.63 in midseason and late season, and the K _cp value was adjusted as 1.29 after soil wetting in rice field under drying–wetting cycle condition. The dual-crop coefficient curves based on locally calibrated K _cbCal and K _cpCor matched well with the measured crop coefficients and performed well in calculating rice evapotranspiration from paddy fields under drying–wetting cycle condition. So it can be concluded that the procedure of dual-crop coefficient method is feasible in rice ET _c estimation, and locally calibrated K _cb and K _cp can improve its performance remarkably.     

Colorimetric Analysis of <Emphasis Type="Italic">Hibiscus</Emphasis> Beverages and their Potential Antioxidant Properties

In food industry, roselle beverages and their subproducts could be functional ingredients since they are an excellent source of bioactive compounds with improved performance due to their important anthocyanins content. The aim of this study was to analyze anthocyanin content and antioxidant properties of aqueous infusions elaborated with color contrasting Hibiscus materials and design a mathematical model in order to predict color-composition relationship. Color measurements of beverages from roselle (Negra, Sudan and Rosa) were made by transmission spectrophotometry, anthocyanins quantification was determined by HPLC, and antioxidant potential was evaluated by in vitro methods (ABTS and FRAP assays). Beverages prepared with particle size minor of 250 μm presented until 4- and 2- times more anthocyanins content and antioxidant capacity respectively, in comparison to beverages prepared with powders with particle size major of 750 μm. Positive correlations among pigments composition and color parameters were found (p?<?0.05), showing that anthocyanins content, antioxidant capacity, C*_ab and h_ab values increased in relation with the smallest particle size of flours. Also, mathematical models were stablished to predict anthocyanin content (r?≥?0.97) and antioxidant capacity (r?≥?0.89) from color data; we propose equations for quick estimation of the antioxidant capacity in the Hibiscus beverages with high anthocyanin content. The obtained models could be an important tool to be used in food industry for pigment characterization or functional compounds with potential health benefits.     

Thermo-Mechanical Characterization of a Thermoplastic Copolyetherester (TPC): Experimental Investigation

In this article, the thermo-mechanical characterization of poly(butylene terephthalate)/poly(tetramethylene oxide) (PBT/PTMO) is studied by thermal analysis, dynamic mechanical analysis, and uniaxial tensile tests. The results of poly(ether esters) show that the melting temperature is equal to T _m =193 °C, which is 31 °C, lower than that of the melting temperature of poly(butylene terephthalate) (PBT). Its glass transition temperature, T _g is equal to -61 °C, determined by DMA. The melting and cooling temperatures (T _m , T _c ) after aging at T₀+48 h and T₀+week are virtually unchanged. Moreover, the results of the tensile tests show that the effect of the low deformation rate reduces the friction resulting from the sliding mechanisms between the amorphous and crystalline parts.     

Influence of different nitrogen forms application on rice photosynthesis: fluorescence with water-saving irrigation in black soil region of Songnen Plain,Northeast China

In order to study the response of the rice photosynthetic-fluorescence characteristics to the application of different nitrogen forms with water-saving irrigation, by using LI-6400XT-type photosynthetic apparatus and other equipment, the fluorescence parameters, stomatal resistance and photosynthetic-CO₂ response curves of rice were measured at the critical stages under water-saving irrigation methods. Results showed that the change trend of ETR and photochemical fluorescence quenching coefficient (Q_p) with different nitrogen forms were declining–rising–declining. Compared with CK (control treatment), ETR and Q_p with NO₃^? treatment were better than the others, which indicated that this treatment was most advantageous to increasing ETR. The electron flow from PSII oxidation-lateral to PSII was enhanced. The potential quantum efficiency (F_v/F_m) was the lowest at tillering stage and the highest at heading stage. Compared with CK, at heading stage, F_v/F_m with NO₃^?, NH₄⁺ NO₃^? and NH₄⁺ treatments was increased by 1.68, 0.61 and 1.81%, respectively, while NO₃^? and NH₄⁺ played a more important role in promoting the ability to capture light. The change trend of non-photochemical fluorescence quenching coefficient with different treatments was not obvious. During the growth period, the stomatal resistance (R_s) was changed dynamically, reaching the second peak at the jointing stage and the highest peak at the milk-ripe stage, and both were higher than CK. The R_s of different nitrogen forms was as NH ₄ ^+? >?NH₄⁺NO ₃ ^?? >?NO₃^?, which showed that with different nitrogen forms, R_s of NO₃^? treatment was low, stomatal opening was correspondingly greater than the other nitrogen forms, and under the same moisture conditions, this treatment of stomatal opening was more beneficial for gas exchange and external CO₂ flowing into the leaf cells, which could increase photosynthetic physiological response. By fitting the parameters of photosynthetic-CO₂ response curve, it was concluded that the photorespiration rate (R_P) was greater than CK, but it was different for three nitrogen treatments during different periods. Rice light saturation point and apparent carboxylation efficiency (α) of NO₃^? treatment during three growth periods were more uniform, indicating that this treatment had a higher utilization rate for low concentration of CO₂. Maximum photosynthetic rate (P_max) with NO₃^? and NH₄⁺ treatments of the three growth periods was 29.396–31.208 and 28.969–31.371, respectively. The CO₂ compensation point and curve angle (θ) had no stable trend during the whole growth period. Therefore, the nitrogen forms could influence the photosynthetic characteristics of the rice leaves, and the result can provide theoretical guidance and scientific basis for increasing the efficiency of nitrogen utilization.     

Seasonal deviation effects foliar endophyte assemblage and diversity in <Emphasis Type="Italic">Asparagus racemosus</Emphasis> and <Emphasis Type="Italic">Hemidesmus indicus</Emphasis>

Background

Fungal endophytes are the living symbionts which cause no apparent damage to the host tissue. The distribution pattern of these endophytes within a host plant is mediated by environmental factors. This study was carried out to explore the fungal endophyte community and their distribution pattern in Asparagus racemosus and Hemidesmus indicus growing in the study area.

Results

Foliar endophytes were isolated for 2 years from A. racemosus and H. indicus at four different seasons (June–August, September–November, December–February, March–May). A total of 5400 (675/season/year) leaf segments harbored 38 fungal species belonging to 17 genera, 12 miscellaneous mycelia sterile from 968 isolates and 13 had yeast like growth. In A. racemosus, Acremonium strictum and Phomopsis sp.1, were dominant with overall relative colonization densities (RCD) of 7.11% and 5.44% respectively, followed by Colletotrichum sp.3 and Colletotrichum sp.1 of 4.89% and 4.83% respectively. In H. indicus the dominant species was A. strictum having higher overall RCD of 5.06%, followed by Fusarium moniliforme and Colletotrichum sp.2 with RCD of 3.83% and 3%, respectively. Further the overall colonization and isolation rates were higher during the wet periods (September–November) in both A. racemosus (92.22% and 95.11%) and H. indicus (82% and 77.11%).

Conclusion

Study samples treated with 0.2% HgCl₂ and 75% EtOH for 30 s and 1 min, respectively, confirmed most favorable method of isolation of the endophytes. Owing to high mean isolation and colonization rates, September–November season proved to be the optimal season for endophyte isolation in both the study plants. Assessing the bioactive potential of these endophytes, may lead to the isolation of novel natural products and metabolites.

     

Effects of various organic amendments on organic carbon pools and water stable aggregates under a scented rice–potato–onion cropping system

Pools of organic carbon are quantified from the soil samples under scented rice crop from different soil layers (0–10, 10–20, and 20–30 cm) under 9 years’ long-term trials with five treatments in scented rice–potato–onion cropping system. These treatments were 100 % NPK (NPK), 50 % recommended NPK through mineral fertilizers + 50 % N as FYM (NPK + FYM), FYM + vermicompost (VC) + neem cake (NC) each equivalent to one-third of recommended N (FYM + VC + NC), 50 % N as FYM + biofertilizer for N + bone meal to substitute phosphorus requirement of crops + phosphate solubilizing bacteria (FYM + BFN + BM + PSB), FYM + vermicompost + neem cake each equivalent to 1/3rd of recommended N + PSB (FYM + VC + NC + PSB). SMBC (479 mg kg^?1), HWEOC (373 mg kg^?1), CWSCHO (235 mg kg^?1), HWSCHO (839 mg kg^?1), and ASCHO (180 mg kg^?1) were found to be the highest in the soil treated with FYM + VC + NC + PSB and the lowest with NPK. The quantity of hot water-extractable carbohydrate content is highest amongst cold water, dilute acid and hot water extractable carbohydrate that decreases with the soil depth irrespective of treatments, except CWEOC. Soil microbial biomass carbon (SMBC) shows significant correlation with CWEOC (r = 0.60**), HWEOC (r = 0.94**), CWSCHO (r = 0.75**), HWSCHO (r = 0.83**), and ASCHO (r = 0.83**) that primed for better aggregate stability irrespective of soil layers up to 30 cm depth. This indicates that labile carbon pools, most specifically water-soluble carbon, carbohydrate, microbial biomass, could be a suitable indicator for evaluation of soil quality, particularly in relation to soil aggregation.     

Identification and fine mapping of <Emphasis Type="Italic">Bph33</Emphasis>, a new brown planthopper resistance gene in rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Background

Host-plant resistance is the most desirable and economic way to overcome BPH damage to rice. As single-gene resistance is easily lost due to the evolution of new BPH biotypes, it is urgent to explore and identify new BPH resistance genes.

Results

In this study, using F_2:3 populations and near-isogenic lines (NILs) derived from crosses between two BPH-resistant Sri Lankan rice cultivars (KOLAYAL and POLIYAL) and a BPH-susceptible cultivar 9311, a new resistance gene Bph33 was fine mapped to a 60-kb region ranging 0.91–0.97 Mb on the short arm of chromosome 4 (4S), which was at least 4 Mb distant from those genes/QTLs (Bph12, Bph15, Bph3, Bph20, QBph4 and QBph4.2) reported before. Seven genes were predicted in this region. Based on sequence and expression analyses, a Leucine Rich Repeat (LRR) family gene (LOC_Os04g02520) was identified as the most possible candidate of Bph33. The gene exhibited continuous and stable resistance from seedling stage to tillering stage, showing both antixenosis and antibiosis effects on BPH.

Conclusion

The results of this study will facilitate map-based cloning and marker-assisted selection of the gene.

     

Implications of the Red Beet Ripening on the Colour and Betalain Composition Relationships

The evolution during ripening of Beta vulgaris (var. Pablo) on colour and betalain composition, not previously conducted in conjunction in red beets, has been examined. According to the results, it could be asserted that the ripening stage significantly (p?<?0.05) influenced on all the studied parameters. On the basis of the betalain content, the optimum ripening stage corresponded to a medium weigh-to-calibre ratio, in the light of the significantly (p?<?0.05) higher content of betalains, especially betanin and vulgaxanthin I. Moreover, colour attributes also differed during ripening, having the medium-ripened beetroots a significantly (p?<?0.05) more reddish hue (h_ab) and lower lightness (L*), probably due to the higher content of betaxanthins in this stage. The colour differences among red beets in the stage II and the rest of stages were visually appreciable (ΔE*_ab?>?3) and mainly qualitative. A new range of opportunities for diversification of colorant market, from a nutritional and colorimetric point of view, could be possible by employing red beets with different stages of ripening.     

Selection of Yield-Associated Morphological and Biochemical Traits Using Correlation and Path Coefficient Analysis in Potato (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.) in the Foothills of North-Western Himalayas

The objective of the study was to assess the direct and indirect effects of 13 important morphological and biochemical traits on yield enhancement in 28 advanced breeding lines of potato (Solanum tuberosum L.) in the foothills of north-western Himalayas. Tuber yield was positively correlated with number of tubers per plant (r?=?0.76), number of stems per plant (r?=?0.53), number of leaves per plant (r?=?0.43) and tuber weight (r?=?0.37). Furthermore, tuber yield exhibited a significant negative correlation with days to maturity (r?=???0.39). Days to 50% emergence had a significant negative correlation with protein content (r?=???0.42). Path analysis revealed that the components of yield, number of tubers per plant and tuber weight, had high positive direct effects (0.876 and 0.618, respectively) on tuber yield, whereas the effects of other traits were low (≤?0.128). Furthermore, tuber weight had an indirect negative effect on tuber yield through the number of tubers. Tuber size had a low correlation (0.19) with tuber yield because a positive indirect effect (0.451) through tuber weight was balanced by a negative indirect effect (??0.254) through tuber number. The number of stems and number of leaves had positive indirect effects (0.377 and 0.377, respectively) on tuber yield through tuber numbers, whereas days to maturity had a negative indirect effect (??0.298) through tuber numbers. There were virtually no indirect effects through the biochemical traits. The implications for potato breeding are discussed.     

Genome-wide association study and candidate gene analysis of rice cadmium accumulation in grain in a diverse rice collection

Background

Cadmium (Cd) accumulation in rice followed by transfer to the food chain causes severe health problems in humans. Breeding of low Cd accumulation varieties is one of the most economical ways to solve the problem. However, information on the identity of rice germplasm with low Cd accumulation is limited, particularly in indica, and the genetic basis of Cd accumulation in rice is not well understood.

Results

Screening of 312 diverse rice accessions revealed that the grain Cd concentrations of these rice accessions ranged from 0.12 to 1.23?mg/kg, with 24 accessions less than 0.20?mg/kg. Three of the 24 accessions belong to indica. Japonica accumulated significantly less Cd than indica (p < 0.001), while tropical japonica accumulated significantly less Cd than temperate japonica (p < 0.01). GWAS in all accessions identified 14 QTLs for Cd accumulation, with 7 identified in indica and 7 identified in japonica subpopulations. No common QTL was identified between indica and japonica. The previously identified genes (OsHMA3, OsNRAMP1, and OsNRAMP5) from japonica were colocalized with QTLs identified in japonica instead of indica. Expression analysis of OsNRAMP2, the candidate gene of the novel QTL (qCd3–2) identified in the present study, demonstrated that OsNRAMP2 was mainly induced in the shoots of high Cd accumulation accessions after Cd treatment. Four amino acid differences were found in the open reading frame of OsNRAMP2 between high and low Cd accumulation accessions. The allele from low Cd accumulation accessions significantly increased the Cd sensitivity and accumulation in yeast. Subcellular localization analysis demonstrated OsNRAMP2 expressed in the tonoplast of rice protoplast.

Conclusion

The results suggest that grain Cd concentrations are significantly different among subgroups, with Cd concentrations decreasing from indica to temperate japonica to tropical japonica. However, considerable variations exist within subgroups. The fact that no common QTL was identified between indica and japonica implies that there is a different genetic basis for determining Cd accumulation between indica and japonica, or that some QTLs for Cd accumulation in rice are subspecies-specific. Through further integrated analysis, it is speculated that OsNRAMP2 could be a novel functional gene associated with Cd accumulation in rice.

     

Synthesis and spectral characterization of novel azomethine disperse dyes derived from pyrazolone moiety and their dyeing performance on polyester fabrics

A series of new azomethine dyes based on pyrazolone system have been synthesized via different routes. The solvatochromism for the dyes was evaluated with respect to spectroscopic properties in various solvents. The dyes were applied as disperse dyes on polyester fabrics and gave shade poor to excellent light fastness, washing, perspiration, sublimation, and rubbing fastness properties. Also the position of color in CIELAB coordinates (L*, a*, b*) and K/S value were investigated.     

Phenotypic and Genomic Modifications Associated with <Emphasis Type="Italic">Globodera pallida</Emphasis> Adaptation to Potato Resistances

Studying phenotypic and genomic modifications associated with pathogen adaptation to resistance is a crucial step to better understand and anticipate resistance breakdown. This short review summarizes recent results obtained using experimentally evolved populations of the potato cyst nematode Globodera pallida. In a first step, the variability of resistance durability was explored in four different potato genotypes carrying the resistance quantitative trait loci (QTL) GpaV_vrn originating from Solanum vernei but differing by their genetic background. The consequences of the adaptation to resistance in terms of local adaptation, cross-virulence and virulence cost were then investigated. Finally, a genome scan approach was performed in order to identify the genomic regions involved in this adaptation. Results showed that nematode populations were able to adapt to the QTL GpaV_vrn, and that the plant genetic background has a strong impact on resistance durability. A trade-off between the adaptations to different resistant potato genotypes was detected, and we also showed that adaptation to the resistance QTL GpaV_vrn from S. vernei did not allow adaptation to the colinear locus from S. sparsipilum (GpaV_spl). Unexpectedly, the adaptation to resistance led to an increase of virulent individual’s fitness on a susceptible host. Moreover, the genome scan approach allowed the highlighting of candidate genomic regions involved in adaptation to host plant resistance. This review shows that experimental evolution is an interesting tool to anticipate the adaptation of pathogen populations and could be very useful for identifying durable strategies for resistance deployment.     

Pb fractionation and redistribution as affected by applied inorganic amendments under different soil moisture regimes and incubation time in saline–sodic Pb-polluted paddy soil

Bioavailability and mobility of lead (Pb) in soils depend upon their partitioning between solution-solid phases and their further fractionation and redistribution among different solid-phase components. However, the dynamics of Pb in salt-affected (saline–sodic) Pb-contaminated (polluted) paddy soil need more exploration particularly under the influence of application of amendments at varying hydrological regimes and residence time. In this context, an incubation study was conducted to investigate the effect of application of three inorganic amendments (gypsum, rock phosphate and diammonium phosphate) on Pb fractions at two soil moisture regimes (flooding regime and 75% field capacity) and two incubation times (after 2 and 30 days) successively in non-saline/sodic and saline–sodic Pb-polluted paddy soils. After applied treatments, the concentration of Pb in five, i.e., exchangeable (F1), carbonate (F2), Fe–Mn oxide (F3), organic matter and sulfide bound (F4) and residual (F5) fractions, was assessed by sequential extraction. The results showed that the Pb spiked in the soils was significantly (P?≤?0.05) transformed from easily extractable (exchangeable and carbonate) fractions into less labile (Fe–Mn oxide, OM–S bound and residual) fractions. Among tested amendments, gypsum performed better in reducing the lability of Pb followed by DAP.     

Enhanced <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> f. sp. <Emphasis Type="Italic">tuberosi</Emphasis> Resistance in Transgenic Potato Expressing a Rice GLP Superoxide Dismutase Gene

Germin like proteins (GLPs) are a large group of related and ubiquitous plant proteins which are considered to be involved in different processes important for plant development and defense. Multiple functional copies of this gene family have been reported in a number of species (wheat, barley, rice, soybean mosses and liverwort), and their role is being evaluated by gene regulation studies and transgenic approaches. To analyze the role of a rice (Oryza sativa) root expressed germin like protein1 OsRGLP1, for its antifungal activity, transgenic potato plants were developed. These transgenic potato plants were molecularly characterized and biologically assessed after inoculation with Fusarium oxysporum f. sp. tuberosi. Functional analysis showed high accumulation of H₂O₂, increased Superoxide Dismutase (SOD) activity and no oxalate oxidase activity (OxO) in transgenics in comparison to nontransformed control. This increased SOD activity, resistance to heat and sensitivity to H₂O₂ suggest it is a Fe-like SOD. OsRGLP1 expression in potato plants exhibited enhanced resistance in comparison to nontransformed wild type plants suggesting its role in providing protection against Fusarium oxysporum f. sp. tuberosi through elevated SOD level. Overall, results suggest that OsRGLP1 is a candidate for the engineering of potato plants with increased fungal tolerance however, the greater height and tuber number was observed. This phenotype associated with the resistance needs to be evaluated to determine if this is a positive or negative feature.     

Effect of <Emphasis Type="Italic">Pistia stratiotes</Emphasis>, cattle manure and wood vinegar (pyroligneous acid) application on growth and yield of organic rainfed rice

The effect of soil incorporation of water lettuce (Pistia stratiotes) and cattle manure and of wood vinegar (pyroligneous acid) foliar application on growth and yield of rainfed rice was studied with a four replications split plot in a farmer’s field in Thailand. P. stratiotes incorporation significantly increased the grain yield over nonincorporation with P. stratiotes. Cattle manure incorporation alone or combined with wood vinegar application significantly increased grain yield over wood vinegar and no-fertilizer application. Incorporation of P. stratiotes combined with cattle manure and wood vinegar application could not provide sufficient N to the rice crop, but it adequate for P and K. Plots with cattle manure incorporation combined with wood vinegar application exhibited the maximum K, P and N content in soil after harvest.     

Natural Dyeing of Wool by Madder (<Emphasis Type="Italic">Rubia tinctorum L</Emphasis>.) Root Extract Using Tannin-based Biomordants: Colorimetric,Fastness and Tensile Assay

In this work, the natural dyeing behavior of woollen yarn with madder (Rubia tinctorum L.) root extract was studied. The effects of different tannin-rich plants (Rhus coriaria, Eucalyptus, Terminalia chebula, Quercus castaneifolia, Pomegranate) extract as biomordants and alum (as a chemical mordant) with two mordanting procedures (pre- and metamordanting) on color characteristics of the dyed samples were also investigated. The CIEDE2000 values, color strength (K/S), washing fastness and tensile property of the mordanted and dyed samples were assessed. Visually, a range of hues from orange to brownish-red were obtained. In general, pre-biomordanted samples with Rhus coriaria (10 %owf), Eucalyptus (10 %owf), Terminalia chebula (5 %owf), Quercus castaneifolia (5 %owf) and Pomegranate (5 %owf) showed almost the same color difference (ΔE₀₀) and wash fastness values compared to those treated with 3 %owf alum. Finally, it was concluded from the comparative studies that the biomordants have good potential to be considered as alternatives to the common chemical mordants.