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Abstract Screen printing of cotton fabric using newly synthesized azo reactive dyes was carried out in the present study. Functional group chemistry and its effect on the printing properties of cotton fabric by varying the nature, number and position of reactive groups of synthesized azo reactive dyes (D1–D6) was studied. Different printing parameters (Temperature, alkali and urea) and their effect was explored on the physicochemical printing properties e.g., fixation, color yield, and penetration of the dyed cotton fabric. Data revealed that dyes with more reactive groups and having linear and planar structures (D-6) showed enhanced printing properties. Spectraflash spectrophotometer was used to evaluate the colorimetric properties of screen-printed cotton fabric and results showed superb color buildup. Printed cotton samples displayed excellent to very good ultraviolet protection factor (UPF). Presence of sulphonate groups and excellent fastness properties may entitle these reactive dyes as commercially viable for urea free printing of cotton fabric.

IntroductionIt is well known that different ecotypes adopt different mechanisms to survive under environmental stress conditions. In this regard, each ecotype showed different type of modifications for their existence in a specific habitat that reflects to their ecological success.MethodsHere, differently adapted ecotypes of Bermuda grass [Cynodon dactylon (L.) Pers.] were collected to evaluate their differential structural and functional modifications that are specific to cope with environmental stress conditions. The soil that adheres ecotypes roots were highly saline in case of DF-SD (Derawar Fort-Saline Desert), UL-HS (Ucchali Lake-Hyper Saline) and G-SSA (Gatwala-Saline Semiarid) ecotypes. Soils of S- HS (Sahianwala-Hyper Saline), S-SW (Sahianwala-Saline Wetland) and PA-RF (Pakka Anna-Reclaimed Field) were basic (pH 9 to 10). Soils of UL-HS and PA- HS (Pakka Anna-Hyper Saline), KKL-S (Kalar Kahar Lake-Saline), BG-NS (Botanic Garden-Non Saline) and G-SSA were rich in organic matter, and soil of BG-NS and DF-SD were rich in minerals. Anatomical modifications were performed by using the free hand sectioning technique and light microscopy.Results and DiscussionDF-SD is one of the best ecotypes which showed anatomical modifications to cope with environmental changes. These modifications included stem cross-sectional area and leaf sheath thickness that contribute towards water storage, vascular tissues for proficient translocation of solutes and trichomes that provide resistance to water loss. On the other hand, sclerification in root is the only notable modification in the Gatwala Saline Semiarid (G-SSA) ecotype from saline arid habitat where rainfall is not as low as in the Cholistan Desert. Two ecotypes from hyper-saline wetlands, UL-HS and KL-HS showed increased number and size of vascular tissue, central cavity and sclerification in stem which are important for solutes conduction, water loss and salts bulk movement, respectively. The ecotype from reclaimed site was not much different from its counterpart from hyper-saline dryland. Overall, anatomical modifications to maintain water conservation are key mechanisms that have been identified as mediating stress tolerance in C. dactylon ecotypes.

Climate change and the consequent alteration in agricultural circumstances enhance the susceptibility of fresh water use particularly in water-scarce regions. Marginal quality water reuse is a common alternative practice but possible perils of metal accretion in plant parts are mostly ignored. The present research aimed to probe the impact of treated wastewater (TWW) and untreated wastewater (UTWW) on metal accumulation in flower petals and their influence on essential oil contents of fragrant Rosa species (R. Gruss-an-teplitz, R. bourboniana, R. centifolia, R. damascena) in a peri-urban area of Faisalabad, Pakistan during January, 2017 to December, 2018. The mineral and chemical contents in canal water (CW) and TWW were less than recommended levels of national environmental quality standards (NEQS) for wastewater of Pakistan. The experimentally UTWW possessed higher electrical conductivity (EC), biological and chemical oxygen demand (BOD and COD), and some metals (Pb, Co, Cr) that were above the permissible levels. The experimental data revealed that except Cr other metals contents in the flower petals were less than the WHO recommended limits (for medicinal plants) under experimental irrigation regimes. Rosa centifolia and R. damascena possessed higher metal i.e. Zn, Cu, Pb, Cr, Co contents while Fe and Ni contents were higher in R. Gruss-an-Teplitz and R. bourboniana respectively. There were twelve constituents which were detected in essential oil by gas chromatography. Major constituents were phenyl ethyl alcohol, citronellol, geranyl acetate, γ- undelactone, methyl eugenol, and limonene whose share was 48.17%, 41.11%, 8.46%, 4.82%, 4.44%, and 4.15% respectively whereas concentrations of other 06 constituents were less than 3.7%. Phenyl ethyl alcohol, lion shared constituent of essential oil was found highest (48.17%) in R. Gruss-an-Teplitz whereas minimum level was recorded in R. damascena (28.84%) under CW. In contrast, citronellol (chief component of fragrance) was highest in R. damascena (41.11%) in UTWW while the lowest level was found in R. Gruss-an-Teplitz (17.41%) in CW. This study confirmed the variations in metal concentrations of Rosa species due to different absorbability of each metal in flower petals. It also indicates that wastewater did not affect the composition but there were quantitative differences in aroma constituents and chemical composition of essential oil.

Strigolactones, a new group of phytohormones, are reported to improve plant tolerance to multiple abiotic stresses. A pot experiment was conducted to investigate the impact of synthetic strigolactone (GR24 at 0.001, 0.01 and 0.1 mg L−1) application on ornamental sunflowers (Helianthus annuus cv. Vincent’s Choice) grown under salt stress (150 mM NaCl). Salt stress was applied after 14 days, and SL was applied 25 days seed sowing. The results showed that amongst various GR24 concentrations, 0.01 mg L−1 proved to be superior, as it enhanced the photosynthetic rate (9.29%), transpiration rate (0.76%), stomatal conductance (77.5%), total soluble protein (0.55%) and K+ (14.63% in roots; 14.87% in shoots) and Ca2+ (12.63% in roots; 11.48% in shoots) contents under control conditions. Similarly, the leaf turgor potential (Ψp), osmotic potential (Ψs) and free proline, glycinebetaine (GB), superoxide dismutase (SOD), catalase (CAT) and peroxide (POD) contents increased by 58.17, 89.95, 159.04, 101.54, 74.42, 175.68 and 53.62%, respectively, under salt stress conditions. The leaf water potential (Ψw) decreased (−0.14%) and the malondialdehyde (MDA) content increased (16.65%) when treated with the 0.001 mg L−1 GR24 level. Meanwhile, hydrogen peroxide (H2O2) and Na+ concentrations in roots and shoots increased by 62.53%, 74.66% and 38.55% under saline conditions with a GR24 level of 0 mg L−1. Regarding the plant biomass, a GR24 level of 0.01 mg L−1 with salt stress greatly decreased the root (−47.27% and −50.45%) and shoot (−44.79% and −59.42%) fresh and dry weights, respectively, compared to control conditions. These results reveal that exogenously applied GR24 might be an effective way to mitigate the perilous impacts of salt stress in ornamental sunflower production. It is suggested that the use of molecular techniques to study different processes in which GR24 could play a vital part in various commercial floricultural crops is extremely imperative and can open novel horizons for future investigations in this exhilarating field of plant hormones.

Water scarcity has critically augmented the need for the exploration of alternative irrigation sources mainly in water-scarce regions. This water scarcity has put tremendous pressure on the agri-based economy of countries such as Pakistan. The reuse of sewage wastewater has been appearing as the only alternative water source, which can lessen our dependence upon freshwater (FW). The current study aimed to scrutinize the influence of treated wastewater (TWW) and untreated wastewater (UTWW) irrigation on the nutrient (N, P, K, Ca, and Na) concentration in different plant parts, i.e., roots, stems, leaves, and flowers, of four scented Rosa species (R. bourboniana, R. centifolia, R. Gruss-an-telpitz, and R. damascena) during the first week of 2018 to the last week of 2019. The experiment was arranged according to the two-factor factorial arrangement i.e., factor I was the irrigation source, while factor II was the Rosa species. The experimental water analysis showed that mineral and chemical concentrations in FW and TWW were within permissible limits of national environmental quality standards (NEQSs) for wastewater. The UTWW of this study possessed a higher electrical conductivity (EC), chemical oxygen demand (COD), biological oxygen demand (BOD), total nitrogen (TN), and metals (Cd, Co, and Pb) than recommended levels. The results revealed that P, K, Ca, and Na contents significantly increased in all studied plant parts of Rosa species as the duration of irrigation with TWW and UTWW increased and vice versa in the case of N contents, while the ratio of N content elevation by applying TWW and UTWW were also not increased compared to other studied nutrients. The nutrients (except Ca) were found as maximum in all plant parts with UTWW compared to FW and TWW irrigation in roses. These stimulations were accredited to the presence of higher essential nutrients and some metals in UTWW. This experiment confirmed the disparities in nutrient contents of scented Rosa species due to the different absorbability of each element in every plant part. Regarding the nutrient accumulation in rose plant tissues, the results of the present study confirm that untreated wastewater must be treated to some extent to grow scented roses where water is scarce.

Plants respond to cold stress by modulating biochemical pathways and array of molecular events. Plant morphology is also affected by the onset of cold conditions culminating at repression in growth as well as yield reduction. As a preventive measure, cascades of complex signal transduction pathways are employed that permit plants to endure freezing or chilling periods. The signaling pathways and related events are regulated by the plant hormonal activity. Recent investigations have provided a prospective understanding about plant response to cold stress by means of developmental pathways e.g., moderate growth involved in cold tolerance. Cold acclimation assays and bioinformatics analyses have revealed the role of potential transcription factors and expression of genes like CBF, COR in response to low temperature stress. Capsella bursa-pastoris is a considerable model plant system for evolutionary and developmental studies. On different occasions it has been proved that C. bursa-pastoris is more capable of tolerating cold than A. thaliana. But, the mechanism for enhanced low or freezing temperature tolerance is still not clear and demands intensive research. Additionally, identification and validation of cold responsive genes in this candidate plant species is imperative for plant stress physiology and molecular breeding studies to improve cold tolerance in crops. We have analyzed the role of different genes and hormones in regulating plant cold resistance with special reference to C. bursa-pastoris. Review of collected data displays potential ability of Capsella as model plant for improvement in cold stress regulation. Information is summarized on cold stress signaling by hormonal control which highlights the substantial achievements and designate gaps that still happen in our understanding.