Flowering Of Ornamental Plants Research Articles

Influence of light intensity on growth and flowering ornamental plants in constructed wetlands

Light is an indispensable source for the photosynthesis of plants, but also for their growth and development. On the other hand, the production of ornamental plants requires multiple nutrients for their proper development, a source available in high concentrations in wastewater. Recent research on constructed wetlands (CWs) that use ornamental plants to treat wastewater and at the same time are used as a means of growth, is considered a sustainable alternative. This study evaluated the influence of light intensity on the growth and flowering of ornamental plants (Lavandula sp., Anthurium sp., Zantedeschia aethiopica and Spathiphyllum wallisii) in constructed wetlands, fed with domestic wastewater. 30 mesocosms of constructed wetlands were used as a culture medium for ornamental plants, the effect of light intensity on the development of the plants was measured, as well as the removal of Nitrogen (N-NO3), phosphate (P-PO4) and biochemical demand of oxygen (DBQ5). The plants were able to adapt and grew healthy in the three-support media with the exception of Lavandula sp., which did not survive in any of the systems, showing that in the months when the light intensity was higher, a higher growth rate was reached to 9.5 % on average. In terms of the removal of N-NO3 (45- 60%), P-PO4 (20-23%) and COD5 (60-85%), no significant differences were found between any of the substrates. The above allows us to affirm that CWs, are suitable means for cultivation of ornamental plants and the development of them is favored with intensities of light in ranges from 720 to 856 µmol · m −2 · s −1, On the other hand, the substrates used proved to be efficient to remove contaminants, but at the same time to facilitate the healthy development of the used ornamental vegetation, with the exception of the lavender sp. Research is required to evaluate the effects of light intensity on the production of ornamental plants in controlled environments.

Efficacy of different primers on growth and yield of tulip (Tulipa gesneriana L.)

Tulip (Tulipa gesneriana L.) is an important and highly valuable flower of the cut flower industry. The most critical step in its cultivation is to break dormancy in order to initiate the growth, especially in tropical and sub-tropical areas of the world. Therefore, the current research was conducted to break bulb dormancy and foster the growth of tulip in Potohar region with the help of different primers. The objective of this study was the selection of best primer at appropriate concentration level to enhance growth, yield and vase life of the flower. Tulip bulbs were treated with different primers: T0 (distilled water), T1 (chitosan @ 5 g/L), T2 (gibberellic acid @ 0.15 g/L), T3 (humic acid 160 g/L), T4 (imidacloprid 19 g/L) and T5 (salicylic acid 0.1 g/L) for 24 hours, respectively. The experiment was laid out using Complete Randomized Design (CRD) with three replications. Statistical results revealed that characteristics including early germination, plant height, number of leaves, stalk length, fresh and dry weight of flower, weight of bulbs, diameter of bulbs and number of daughter bulbs were significantly increased in T2. Whereas, leaf area, diameter of stem and flower was maximum in T0. Plants under T3 showed an increase in chlorophyll content of leaves. While floral characteristics like early formation and opening of flower bud, more number of flowers and vase life were improved in T1. Thus, statistical results showed that priming can effectively help to improve morpho-physiological attributes of tulip.

Adubação fosfatada no desenvolvimento de Hemerocallis fulva L.

In clayey Oxisol from the Brazilian Cerrado, where there is high P fixation, the phosphorus fertilization is necessary to increase the growth and flowering of ornamental plants. Thus, the objective of this study was to analyze the development of Hemerocallis as affected by phosphorus application in clayey Oxisol (Typic Haplustox). The experiment was conducted at the Gardening area of University Federal of Grande Dourados (UFGD) in Dourados-MS, Brazil. The experimental design was a randomized block with four replications. The treatments consisted of four P2O5 rates (0, 250, 500, 1000 kg ha-1) using simple superphosphate as source. The experimental unit was composed of one Hemerocallis fulva ‘Flore Pleno’ plant, grown in a plastic pot (5 liters). Phosphorus fertilization increased linearly the concentration of phosphorus in the soil; the plant had maximum absorption (5.26 g kg-1) with the calculated dose of 727 kg ha-1 P2O5. H. fulva has a root system that develops best under high availability of P, however, for aerial part, the maximum of shoots fresh mass (451.1 g) was obtained with 427 kg ha-1 of P2O5. Number of flower buds, flower diameter and height flower stalks were higher in the presence of phosphorus.

Molecular Cloning of Promoter of <i>AP3</i> Gene from <i>Arabidopsis thaliana</i> Ecotype (Col) and Construction of the Plant Expression Vector

Belonging to MADS-Box gene family, APETALA3 ( AP3 ) gene of Arabidopsis floral organ class B is expressed in petals and stamens specifically. AP3 gene which encodes a transcription factor controls the development of petals and stamens of dicotyledons by cooperation with class A and class C genes, respectively. The results showed that the promoter of AP3 was the flower-specific expression promoter. Therefore, the cloning and functional identification of AP3 gene promoter from Arabidopsis thaliana will play significant effects on the oriented improvement of the commercial traits related to the flowers of ornamental plants. Here, a pair of specific PCR primers was designed according to the promoter sequence of AP3 gene of Arabidopsis thaliana ecotype (Ler) reported in GenBank (U30729). A length of 1 767 bp of AP3 gene promoter was obtained from Arabidopsis thaliana ecotype (Col) by using PCR technique with high-fidelity DNA polymerase KOD-plus, named as pAtAP3 , the GenBank accession No. is FJ619533. Online Bl2seq analysis indicated that the sequence similarity between pAtAP3 and U30729 was 98%. It also showed that the sequence similarity between pAtAP3 and the BAC clone T12E18 (AL132971) of Arabidopsis thaliana ecotype (Col) from 9 264 to 11 030 was up to 100%, and its downstream sequence encoded AP3 protein (CAB81799), which approved that the sequence we cloned was the promoter of AP3 gene of Arabidopsis thaliana ecotype (Col). Online PLACE analysis displayed that pAtAP3 contained the basic cis -elements of promoter such as TATA-box and CAAT-box. It also comprised several cis -elements related to flower-specific expression, such as CArG1, CArG2, CArG3 and anther-box. Moreover, plant expression vector of pAtAP3 :: GUS was successfully constructed in this research, which would lay the foundation for functional identification of the AP3 promoter of Arabidopsis thaliana ecotype (Col).