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The objectives of this study were to clarify and evaluate the water quality of a number of rivers in East Kalimantan province of Indonesia. For this purpose, our study successfully utilized the benthic macroinvertebrates diversity as well as physicalchemical parameters of river's water. For instance, based on the values of Average Score per Taxon (ASPT) and the National Sanitation Foundation-Water Quality Index (NSF-WQI), Karang Mumus River was categorized as polluted with Chironomus sp. and Melanoides tuberculata as codominant taxa. In addition, Jembayan River exhibited doubtful or moderate quality containing M. tuberculata and A. parvula as codominant taxa. However, Pampang River was found to be the cleanest river with Odonata and Baetidae families as codominant taxa.

Phalaenopsis amboinensis, an epiphytic orchid, has a great potential for commercial exploitation in the cut-flower industry. It is difficult to propagate vegetatively as it naturally grows slowly. Therefore, there is a need to improve the propagation methods to avoid endangering its natural populations. The objective of this study was to identify the best medium and organic supplements for seed germination and plantlets development of P. amboinensis. Seeds from 4-month-old hand-pollinated orchids were sown on different strengths of MS and VW culture media: Murashige and Skoog (MS), 1/2 MS, Vacin and Went (VW), and 1/2 VW. Optimum seed germination, i.e., 90.7%, was achieved on VW medium. VW medium was suitable for seedling formation and allowed 51.4% of seedling development from protocorm within 10 weeks of culture. When 15% (v/v) coconut water was added together with banana homogenate (10 g·L−1) to the VW medium, the plantlets grew to the highest length and had the highest dry weight (62.1 mm and 15.5 g, respectively). The roots and leaves of the plantlets grew vigorously in this medium. Plants regenerated via in vitro seed germination processes were successfully acclimatized in greenhouse conditions, and the survival rate was more than 85%.

In nature, orchid seed germination is obligatory following infection by mycorrhizal fungi, which supplies the developing embryo with water, carbohydrates, vitamins, and minerals, causing the seeds to germinate relatively slowly and at a low germination rate. The nonsymbiotic germination of orchid seeds found in 1922 is applicable to in vitro propagation. The success of seed germination in vitro is influenced by supplementation with organic compounds. Here, we review the scientific literature in terms of the contents and role of organic supplements in promoting seed germination, protocorm development, and seedling growth in orchids. We systematically collected information from scientific literature databases including Scopus, Google Scholar, and ProQuest, as well as published books and conference proceedings. Various organic compounds, i.e., coconut water (CW), peptone (P), banana homogenate (BH), potato homogenate (PH), chitosan (CHT), tomato juice (TJ), and yeast extract (YE), can promote seed germination and growth and development of various orchids. They also stimulate seedling development, formation of protocorm-like bodies (PLBs), plantlet growth, and multiple shoot formation. The addition of organic compounds to culture media, individually or in combination, accelerates seed germination and seedling development. Different types and concentrations of organic nutrients are needed for the success of in vitro cultures, depending on the species and genotype.

In this study, seeds of 10 species of epiphytic orchids were examined using light and scanning electron microscope. Quantitative and qualitative characters were analyzed. All the presently investigated seeds showed are transparent with visible embryo and remarkable embryo color variations (such as pale yellow, light yellow, shiny yellow to yellow, orange, and white). The species showed two groups in seed shape (fusiform and filiform), prolate and oval-shaped embryo, positioned at the center of the long axis and near apical pole. Embryo in prolate shaped and near apical pole position was only in D. antennatum. Based on our investigation, there are variations in seed and embryo volume as well as percentage air space in different taxa of orchids. The highest air space percentages were found in D. leporinum. According to the ornamentation of testa cells, 3 types of seeds were discovered in this genus. Additionally, the clear variation in the testa ornamentation pattern includes the species of D. leporinum, where the testa cells were in the medial regular rectangles, but in the apical and basal pole they are polygonal and irregularly oriented; the testa cells of D. antennatum are polygonal and irregularly oriented and those of D. purpureum are longitudinally oriented with regular rectangles.

The objective of this study was to determine the capacity, process, and kinetics of phosphorus (PO 4-P) nutrients pollutant removal in constructed wetlands with Equisetum hymale plants. This research was conducted by using a batch system constructed wetlands with detention time variation of 1-5 days and using gravel, sand, and soil as the media. The laundry wastewater used for this research was collected from commercial activity in Surabaya city. The results of this research showed that the removal efficiency of PO 4-P using the constructed wetlands with Equisetum hymale was between the range of 95.49-99.43%. The removal process was done by screening-adsorption, and the sedimentation mechanisms from the media, and the biosorpsion by the plants was shown by the increasing content of PO 4-P in soil and plants, which amounted to 14.80% and 9.23% respectively. The removal kinetics of PO 4-P was according to the second-order model with value of R 2 = 0.99.

<p><em>Dendrobium antennatum</em> has high economic value as cut flowers and flowerpots. Like orchid seeds in general, <em>D. antennatum</em> is difficult to germinate under natural conditions. This study aimed to determine the effect of coconut water on seed germination and embryo development, as well as the effect of NAA on shoots development of <em>D. antennatum</em>. This study consisted of two stages. In the first stage, the 12 weeks-old seeds after pollination were sown on MS medium containing 2 g/L peptone + 0%; 5%; 10%; and 20% coconut water. After 8 weeks of culture, the seeds germinated and the shoot formed were recorded. The highest in seed germination (92.2%) and the formation of shoots (51.4%) were obtained when seeds were cultured on MS medium containing 2 g/L peptone + 20% coconut water. In the second stage, the shoots were sub-cultured on MS medium containing 1 mg/L thidiazuron + 0 mg/L; 1 mg/L; 2 mg/L; and 3 mg/L NAA. After 16 weeks of sub-culture, the height of <em>plantlets</em>, the length of the roots and leaves, number of leaves and roots formed were recorded. MS medium containing 1 mg/L thidiazuron + 1 mg/L NAA was the most suitable for the shoots development of <em>D.antennatum</em>. The embryo development of<em> D.antennatum in vitro</em> begins with the enlargement of embryo, with further it emerges from the seed coat (germinated) followed by the formation of the apical meristems to form the shoots and the roots.</p><p> </p>

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