Exogenous applications of gibberellic acid modulate the growth, flowering and longevity of calla lily

Calla lily (Zantedeschia aethiopica (L.) Spreng.) is an important ornamental crop used in garden landscapes, floral arrangements, and medicinal applications. Gibberellic acid (GA3) is actively involved in cell elongation, growth, physiology, and flowering. In addition, it is an environmentally-friendly compound which can be applied to plants to increase the ornamental production. Therefore, the present study was designed with three GA3 spray times viz., single, double and triple spray and five exogenous applications of gibberellic acid concentrations viz., 0, 25, 50, 100, and 200 mg L−1 with factorial randomized block design. Results revealed that the interaction effect of combinations of two time applications of GA3 at 100 mg L−1 induced higher growth parameters over control. Significantly higher physiological parameters viz., photosynthetic rate (14.3 μmol m−2s−1), number of stomata (26.5 mm−2), stomatal conductance (0.28 mmol m−2s−1), and transpiration rate (3.6 mmol m−2s−1) were reported when plants were treated twice with 100 mg L−1 GA3. Similarly, among flowering traits, days to flower were significantly low in plants treated two-time spray at GA3 100 mg L−1 (169.8 days). The number of flowers in the double spray at GA3 100 mg L−1 treatment increased by 11.3 and 23.7% over triple spray and control, respectively. Vase life was also significantly higher in plants treated with double spray at GA3 100 mg L−1 (6.3 days). The regression equation and correlation matrix indicated a strong relationship between growth, flowering and GA3 concentrations up to 100 mg L−1. The PCA analysis revealed that the calla lily crop is positively affected by spray timing and GA3 treatments. In the context of vegetative, reproductive, and longevity parameters of the crop, a dual spray of 100 mg L−1 GA3 can be recommended to small scale farmers and commercial growers as an alternative technique for promoting growth, yield and improving the ornamental value for commercial level production

Propagation of <i>Jasminum parkeri</i>: A Critically Endangered Wild Ornamental Woody Shrub from Western Himalaya

Jasminum parkeri Dunn is a narrowly endemic, critically endangered woody ornamental shrub confined to sub-temperate zone of Western Himalayas, and rediscovered from its type locality after a lapse of about 100 years. In the present study, a propagation technique of J. parkeri, using stem cuttings, was established for the first time through application of auxins, namely, indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA), and indole-3-butyric acid (IBA), at varying concentrations ranging from 1000 to 4000 ppm. The highest rooting percentage (98.33% (85.68% ± 4.32)), number of primary roots (36), root length (29.68 cm) and survival percentage (96.67% (83.85% ± 6.16)) were recorded for cuttings treated with 3000 ppm NAA. The phenological comparison between pot plants propagated through seeds and stem cuttings in a naturally ventilated polyhouse revealed a reduction in vegetative and flowering phases in cutting raised plants. Additionally, a noteworthy adaptive behavior of two weeks of early flowering and four weeks of extended flowering (February to October) was observed in plants raised under polyhouse conditions. This method will help in protecting the species from population decline, thereby significantly increasing its potential to be harnessed as an ornamental plant in India. Furthermore, plants grown ex situ will be reintroduced in natural populations

Phytoremediation toward Air Pollutants: Latest Status and Current Developments

In recent years, air pollution has become one of the major environmental concerns that threaten health of the living organisms and its surroundings. Increasing urbanization, industrialization, and other anthropogenic activities impaired the air quality of indoor and outdoor environment. However, global organizations are focusing on ecological and biological means of solutions to reduce or eliminate dangerous contaminants from ecosystems in a sustainable manner. In this fact, plants are capable of improving or cleansing air quality and reduce the concentration of harmful pollutants from the environment through various remediation processes. Plants interact with air pollutants and fix them through various biological mechanisms in both associated and non-associated forms of microbes. In association forms, the mutualistic interaction of plant and microbes leads to higher growth efficiency of plants and results in enhanced pollutant degradation in rhizosphere as well as phyllosphere. In this background, the book chapter provides a comprehensive discussion of the existing literature and recent advances in phytoremediation process for the mitigation of harmful air pollutants. The role of indoor plants and aids for the enhancement of phytoremediation process towards air pollutants are also discussed

19% Efficient P3CT-Na Based MAPbI3 Solar Cells with a Simple Double-Filtering Process

A high-efficiency inverted-type CH3NH3PbI3 (MAPbI3) solar cell was fabricated by using a ultrathin poly[3-(4-carboxybutyl)thiophene-2,5-diyl]-Na (P3CT-Na) film as the hole transport layer. The averaged power conversion efficiency (PCE) can be largely increased from 11.72 to 18.92% with a double-filtering process of the P3CT-Na solution mainly due to the increase in short-circuit current density (JSC) from 19.43 to 23.88 mA/cm2, which means that the molecular packing structure of P3CT-Na thin film can influence the formation of the MAPbI3 thin film and the contact quality at the MAPbI3/P3CT-Na interface. Zeta potentials, atomic-force microscopic images, absorbance spectra, photoluminescence spectra, X-ray diffraction patterns, and Raman scattering spectra are used to understand the improvement in the JSC. Besides, the light intensity-dependent and wavelength-dependent photovoltaic performance of the MAPbI3 solar cells shows that the P3CT-Na thin film is not only used as the hole transport layer but also plays an important role during the formation of a high-quality MAPbI3 thin film. It is noted that the PCE values of the best P3CT-Na based MAPbI3 solar cell are higher than 30% in the yellow-to-near infrared wavelength range under low light intensities. On the other hand, it is predicted that the double-filtering method can be readily used to increase the PCE of polymer based solar cells

Conformal Loading Effects of P3CT-Na Polymers on the Performance of Inverted Perovskite Solar Cells

The conformal loading effects of P3CT-Na polymers on ITO/glass samples were investigated using different concentrations of P3TC-Na/water solution, which significantly influenced the device efficiency of the resultant inverted perovskite solar cells. The obtained water-droplet contact angle images, surface morphological images, photoluminescence spectra and X-ray diffraction patterns show that the hydrophilic moiety of the P3CT-Na polymers plays an important role in the conformal loading effects, thereby resulting in a smoother perovskite crystalline film due to the formation of merged grains. It is noted that the average power conversion efficiency increases from 14.83% to 17.27% with a decrease in the concentration of the P3CT-Na/water solution from 60 wt% to 48 wt%