全國中小學科展

植物學

福木葉萃取液應用於生物除草劑之可行性評估 Evaluation of bioherbicidal potential of Garcinia subelliptica Merr. Leaves.

大花咸豐草(Bidens pilosa L.) 為主要的入侵植物之一,菲島福木(Garcinia subelliptica Merr.)能否作為生物除草劑,抑制大花咸豐草的危害。以最佳萌發條件培養三種作物與雜草-大花咸豐草種子,福木葉萃取液皆能抑制種子萌發,且對大花咸豐草的抑制效果最顯著。進行幼苗測試,福木葉萃取液可抑制萵苣主根長、小麥草植株與不定根生長,亦能抑制大花咸豐草植株與主根生長,並促進大花咸豐草過氧化氫酶的活性。本研究認為福木深具發展成生物除草劑的潛力,但考慮福木相剋作用與大花咸豐草和作物競爭有下列兩種情形:(1)萵苣:相剋<相剋+競爭競爭(2)小麥草:相剋+競爭<競爭<相剋,故建議在兩種萵苣播種前使用5%福木葉萃取液,抑制大花咸豐草種子萌發;小麥草需等大花咸豐草叢生後再使用10%福木葉萃取液,可促進小麥草的生長;單獨生長的大花咸豐草則使用10%福木葉萃取液能夠有效抑制其生長。

Let There Be (Optimal) Light

On average, the agricultural sector uses 70% of water withdrawals worldwide to produce crops1 and contributes to the eutrophication of lakes by using nutrients that are leached from the soils into lakes and reservoirs2. Vertical farming has great potential to remedy some of these issues. By growing plants vertically in controlled environments with artificial light and reusing the water, vertical farms use op to 99% less water3 and can produce up to 10 times the yield per square meter4 compared to traditional greenhouses. This improved efficiency comes at a cost; on average, vertical farms use more than 600% more energy per kilogramme of crop compared to traditional greenhouses5. 55% of this energy use is due to the use of artificial lighting6. Even though a lot of research is conducted on yield optimisation of crops in vertical farming, few research articles focus on the growth efficiency of crops to reduce the energy use in vertical farms. Only a few previous studies have tested photoperiods under 10 h·d-1. This study focuses on reducing the energy costs of light use in vertical farms by finding the photoperiod with highest energy use efficiency for the leafy vegetable arugula (eruca sativa). Energy use efficiency is defined as fresh mass per unit of electricity input (measured in kWh). In this study, arugula plants were exposed to LED growth light, with photoperiods ranging from 0 h·d-1 to 24 h·d-1 (0 h·d-1, 4 h·d-1, 7 h·d-1, 9 h·d-1, 12 h·d-1, 14 h·d-1, 16 h·d-1 and 24 h·d-1) and a PPFD of 800 μmol·m-2·s-1. The photoperiod 7 h·d-1 had the highest energy use efficiency of all photoperiods and, if used in vertical farms, this could account for approximately a 10 percent decrease in energy per kilogramme used in vertical farms (a 4 kWh decrease), with the planting density of 1400 plants per m2. This could amount to a yearly energy saving of 4,000,000 kWh per vertical farm (based on the yearly harvest of the vertical farm Nordic Harvest). This could help make vertical farming a more sustainable plant production for the future and in turn, help farming protect our water resources instead of consuming and polluting.

大「逆」不道—局部逆境下植物體內傳訊與物質分配機制

When a leaf of a plant encounters stress, how does the plant convey the stress signal to other tissues and manage nutrient distribution? This field of study has been largely unexplored. However, the unique interconnected frond structure of Lemna trisulca, along with the use of a divided Petri dish, is very suitable for handling localized stress and investigating the mechanisms of intracellular signaling and nutrient distribution. Research has shown that when the mother leaf experiences localized stress, it releases healthy daughter leaves to minimize collateral damage to the daughter leaves. Conversely, when the daughter leaves face localized stress, the mother leaf chooses to retain them and continues supplying them with nutrients to support their survival. In-depth studies revealed that stressed daughter leaves accumulate Reactive Oxygen Species (ROS), triggering nutrient distribution by sending a distress signal to the mother leaf. This prompts the mother leaf to use Ca2+ as a signaling molecule to deliver nutrients to the daughter leaves. Selective detachment is regulated and triggered by the interaction between Ca2+ and ROS within the mother leaf. When the mother leaf undergoes stress, Ca2+ acts upstream to induce ROS accumulation at the nodes, sending a unidirectional detachment signal to the daughter leaves. This causes ROS accumulation at the daughter leaf nodes, inducing detachment and thereby reducing the collateral damage the daughter leaf could experience due to the mother leaves.

Exploiting the beneficial role of Biochar and Titanium (Ti) as a Sustainable and Green Strategy for Improving Agricultural Output in Saudi Arabia: Wheat as an Using Wheat as a Model

The present research work aimed to assess the impact of biochar (BC) amendment (5%) and foliar supplementation of titanium (Ti) at a concentration of 50 mg L-1 TiO2 on the growth, chlorophyll content, and biochemical parameters of wheat (Triticum aestivum L). The results demonstrated significant improvements in several aspects of wheat physiology due to these treatments, both individually and in combination. Plant height, as well as fresh and dry weight of wheat, exhibited substantial increases when subjected to Ti and BC treatments, with the highest enhancements observed in plants treated with both Ti and BC. Furthermore, chlorophyll content, including chlorophyll a, chlorophyll b, total chlorophylls, and carotenoids, showed marked increases in response to individual Ti and BC treatments, with even greater improvements when both treatments were combined. In terms of biochemical parameters, the content of proline, sugars, and free amino acids significantly increased in plants grown in soils amended with BC. Additionally, foliar Ti treatment led to elevated levels of these biochemical constituents. The combined treatment of Ti and BC resulted in the most pronounced effects. Moreover, oxidative damage parameters, such as hydrogen peroxide, lipid peroxide, and electrolyte leakage, were notably reduced in plants subjected to Ti and BC treatments, either individually or together. The activity of antioxidant enzymes, including superoxide dismutase, catalase, and ascorbate peroxidase, exhibited significant increases in response to Ti and BC treatments, further emphasizing their beneficial effects on wheat plants. Overall, this investigation shows that biochar amendment and titanium foliar supplementation both have beneficial effects on wheat development and biochemical parameters; these findings may be relevant to efforts to increase crop productivity and stress tolerance.

Evaluation of the Effect of Different Nutrients' Concentration and Composition on Hydroponically Grown Plant

As the world population grows, the demand of food products grows as well and there will be an expected food crisis in the coming years. To prevent those crises, alternative food farming methods must be used. This paper studied two farming systems in different conditions, to compare and find the best, natural and cost-effective system that will cover the current and future demand. The system which can also be used in those areas where soil is less cultivated with insufficient aeration. The first system is the soil-based system (traditional), and the other is hydroponic system. Hydroponic is a technique of growing plants in nutrient solutions with or without the use of an inert medium. Two types of seeds; peas and spinach were observed in both systems over a period of 25 days. In hydroponic plants coco peat was used in place of soil along with the Aegis nutrient. 8 plants were seeded for both types of plants in different systems, conditions, concentrations and pH to conclude the best condition. Growth parameters of all plants including root, shoot and leaf length were observed and recorded daily. On the uprooting, their weight (g), no. of root hairs and used nutrient’s volume(ml) were also recorded. Fungus and insects were seen in the soil plants. The results executed that the growth was maximum in spinach having normal manufacturer nutrient’s spray concentration(1.25ml/625ml) with pH 6 and in peas having normal supplier concentration (5ml/625ml) with pH 4. So, it can be concluded that hydroponic spinach, which is a green leafy plant, can ideally grow at the pH of 6 and peas in slightly acidic condition. Hydroponic planting system has a better growth effect than traditional soil system and this system don’t need any fertilizer, insecticide, pesticide, fungicide and herbicide. While soil plants’ growth was adversely affected by fungus and insects in the absence of these chemicals which can contaminate our food and make it less hygienic for our health. This result achieves the aim of this paper which is finding a planting system and its conditions that can increase the productivity to cover the food demand.

熱不倒的番茄—耐熱細菌對番茄根莖之研究

本次實驗以地熱溫泉區的土壤中所篩選出的8隻耐熱菌種,並加以純化、液態培養,將8種菌液稀釋成度三種不同濃度(100X、200X、500X),以恆溫培養箱控制環境溫度(25℃、30℃、35℃)模擬環境變因,並測試和定量菌株的溶磷、固氮能力,亦測試載鐵、抗番茄萎凋菌能力及對於聖女番茄及桃紅番茄所帶來的影響。本研究發現 LC26 及 LC28 可於熱逆境下顯著促進聖女番茄生長,此外LC03亦能於熱逆境下明顯促進桃紅番茄生長。本研究也發現LC03、LC26及LC28對玉米及胡蘿蔔有最好的促進生長效果,而對青江菜有最明顯的抑制生長效果,可作為輪耕作物之參考。最後本研究發現這三隻菌種皆對大花咸豐草之生長有抑制情形,其中以LC26(500X)抑制效果最佳。

Decoding Climate Resilience: Functional Profiling of Protein Phosphatase 2C Family Genes for Abiotic Stress Tolerance in Rice

Problem • Rice is the primary cereal crop consumed by nearly half the population worldwide • By 2050, there will be a 50% increase in demand for rice • The world’s poor populations depend more on rice, both for income and consumption, than any other food. Rice is the single-largest source of employment and income for rural people • Worldwide, 51–82% of agricultural crop yield is lost annually due to abiotic stress due to climate change • Climate change causes extreme temperatures, erratic rainfall, dangerous droughts, and increased salinity from rising sea levels Solution • To adapt to abiotic stress, rice has intricate signaling pathways, particularly those mediated by the phytohormone abscisic acid (ABA), that cause an increase in stress tolerance • Clade A genes of the Protein Phosphatase 2C (PP2C) gene family are known to be negative regulators of the ABA signaling pathway. • “Deleting” these genes activates the ABA pathway and increases stress tolerance in rice without inducing stress CRISPR gene editing technology is the ideal solution Research Goal • While the role of PP2C genes in stress response is recognized, there is a gap in understanding the specific genes within this family that contribute significantly to stress signaling. Furthermore, there is a need for a detailed investigation into the effects of targeted CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) genome editing on rice stress response pathways.

Plantastic Pods: The Grow Stick Rooting Revolution for Seeds & Cuttings

Cultivating plants from seeds or cuttings is a fundamental aspect of gardening and agriculture. While traditional methods have been practiced for centuries, there is a persistent need for innovative and efficient approaches to enhance plant growth and development. This section explores the challenges associated with traditional propagation methods and examines potential solutions offered by emerging technologies and materials. Plant propagation is necessary to allow efficient multiplication and distribution of desirable plant varieties (Sorensen & Garland, 2024). Plant propagation is the process of creating new plants. There are two primary methods of propagation: sexual and asexual. .Sexual propagation involves the union of pollen and egg, drawing genetic material from two parent plants to create a new, genetically diverse offspring. This process utilizes the floral parts of a plant. .Asexual propagation, on the other hand, involves taking a part of a single parent plant and inducing it to regenerate into a new plant. The resulting offspring is genetically identical to its parent. This method utilises the vegetative parts of a plant, such as stems, roots, or leaves. One emerging technology that has garnered attention in this field is the use of cocopeat, a sustainable growing medium derived from coconut husks (Pane et al. 2021). Cocopeat has been extensively studied as a potential alternative to peat moss in plant propagation (Gericke, 1940). It offers a favourable balance between air porosity and water holding capacity, promoting root development and nutrient uptake (Kalaivani and Jawaharlal, 2019). Furthermore, cocopeat is a renewable and environmentally-friendly resource, making it an attractive option for sustainable seedling cultivation. Research has shown that the use of cocopeat as a growing medium can enhance the growth of both vegetables and various ornamental plants, such as Impatiens. The biostimulant effect of the Trichoderma atroviride fungus, which can readily colonize coir, has been observed to increase aboveground biomass, flower production, pigments, and nutrient concentration in these plants (Traversari et al., 2024).

高山生態群聚植物集中開花與昆蟲交互作用網絡之研究

本研究首度以植物學、花粉學、昆蟲學及生態統計學探討臺灣高山傳粉生態網絡。花季中期以蜂類為主,後期為蠅類。昆蟲及植物交互網絡緊密連結無子群體,仰賴優勢物種支撐。蜂期為高山薔薇、玉山櫻草、貓兒菊、信義雄蜂;蠅期為一枝黃花、貓兒菊、家蠅。此兩期昆蟲與植物的穩健性不足,蠅期更易崩解。蜂類訪花具多樣性,蠅類訪花較專一。因蜂類、蠅類習性與身體特徵不相同,蠅類對花展幅 (Visit Unit)大、花冠筒淺、花冠筒筒徑小、還原糖含量高、花粉及花蜜之間的距離大、柱頭面積小的植物較能專一攜帶其花粉。共用傳粉者帶來異種花粉,以GLMM分析同異種花粉數量變化關係,發現一起開花略助於授粉。貓兒菊已入侵成為優勢物種,花粉汙染90%的物種,必須移除。

大「逆」不道—局部逆境下植物體內傳訊與物質分配機制

When a leaf of a plant encounters stress, how does the plant convey the stress signal to other tissues and manage nutrient distribution? This field of study has been largely unexplored. However, the unique interconnected frond structure of Lemna trisulca, along with the use of a divided Petri dish, is very suitable for handling localized stress and investigating the mechanisms of intracellular signaling and nutrient distribution. Research has shown that when the mother leaf experiences localized stress, it releases healthy daughter leaves to minimize collateral damage to the daughter leaves. Conversely, when the daughter leaves face localized stress, the mother leaf chooses to retain them and continues supplying them with nutrients to support their survival. In-depth studies revealed that stressed daughter leaves accumulate Reactive Oxygen Species (ROS), triggering nutrient distribution by sending a distress signal to the mother leaf. This prompts the mother leaf to use Ca2+ as a signaling molecule to deliver nutrients to the daughter leaves. Selective detachment is regulated and triggered by the interaction between Ca2+ and ROS within the mother leaf. When the mother leaf undergoes stress, Ca2+ acts upstream to induce ROS accumulation at the nodes, sending a unidirectional detachment signal to the daughter leaves. This causes ROS accumulation at the daughter leaf nodes, inducing detachment and thereby reducing the collateral damage the daughter leaf could experience due to the mother leaves.