植物學

Previously, I studied the acute effects of a common broadleaf herbicide, Killex (by Montsano) and a pesticide, Spidercide (by Wilson), on cytoplasmic streaming in detached leaves from the pond weed, Elodea canadensis. I found that Killex, active ingredient 2-4D, an auxin analog, applied at the recommended dose decreased the rate of cytoplasmic streaming by 64% over a 20 minute observational period. The Spidercide, active ingredient d-trans allethrin, a Na+ channel activator, stopped cytoplasmic streaming after a 5 minute exposure and no recovery was observed during the 20 minute observational period.

Few plants can grow in the place where Wedelia trilobata grows. In the following experiment, the leaves ans stalks(of the plants from Wedelia trilobata) are extracted for experimental purpose .The data and records of the experiment have shown that Wedelia trilo ata indeed refain the growth of plants such as mung bean, teeding seed, yeast’s respiration and the photosynthesis. We use the function of dieing the polyphenols to know that the Wedelia trilobata can produce Allelochemicals called as the polyphemols The mesophycell produce the polyphemols from chloroplast of cortex,the polyphemols transport to root and release from root exudation. The plant will absorb polyphemols of the soil, and will affect the growth of the plant. If we can separate and purify the Allelochemicals, we can make it as natural herbicideb. 南美蟛蜞菊所在之處，少有其他植物，本實驗採南美蟛蜞菊植栽區之土壤與南美蟛蜞菊莖或葉之萃取液進行相剋作用之研究，結果顯示南美蟛蜞菊確實會抑制小麥與綠豆種子萌發及幼苗生長，並抑制酵母菌的呼吸作用及植物光合作用中之光反應。 利用多酚類染色方法得知南美蟛蜞菊產生的相剋化合物為多酚類，且該多酚類由葉肉細胞與莖內皮層中具葉綠體之細胞產生，經韌皮部輸送至根，再由根經泌濾作用釋出。土壤中的多酚類會被植物吸收，進而影響植物的生長與發育。 若能將該相剋化合物---多酚類分離與純化，或可作為具選擇性之天然除草劑。

我一直在想，為什麼植物的美麗不能永恆呢？美麗的花朵，伴隨答淡雅的香氣，往往能美化環境，更能淨化人心，自小生長在鄉間的我，更能感受到這份來自花草的神奇力量，因此深深愛上這花草世界．但為何花朵的美麗總是短暫，為了想讓植物開花的時間長久，於是，我著手進行在自然科技雜誌及網路上搜尋相關的資料及訊息，但是找到的大多都是使生長速率變快的報告，卻找不到使生長速率變慢的報告。終於，曾經有人運用圓周運動的原理，而成功的使動物的生長速率變慢，於是，我針對直線運動及圓周運動分別依速度快及速度慢來分成四組，以及一組靜止狀態的綠豆，將五組實驗後的數據相互作比較，結果發現，除了陽光、水、空氣、土壤、養分及本身具有的胚胎外，在不同的運動狀態下也會影響到植物的生長速率 ·I was thinking about the reason why the beauty of plants couldn’t last forever. The beauty of flowers that accompanied with sweet-smelling could beautify the landscapes and purify our heart. I felt strongly about the magic power of the plant because I lived in the country in my childhood. Therefore, I loved plants deeply. Why was the beauty of flowers transient? As a result. I started to search for the related data and information on science and technology magazines and Internet. Most of the reports increase the growth rate of plants, but I cou1dn find the reports about slowing down the growth rate.At last, someone had successfully used the principle of circumference movement to slow down the growth rate of animals. Therefore, I focused on linear and circumference movement and divided them into four groups and one group of green beans with still state. I compared the data of five groups, and found that different movement affected the growth rate of plants m addition to sun, water, air, soil, and embryo.

阿拉伯芥中，生物時鐘 (circadian clock) 會產生 24 小時之概日韻律 (circadian rhythm) 使植物適應環境中的溫度與光線變化。在阿拉伯芥中目前已經發現 LIGHT-REGULATED WD1 (LWD1) 和 LWD2 基因和調控生物時鐘有關，使其維持正常的一天 24 小時週期。當 LWD1 與LWD2 基因產生突變時，植物的生物時鐘週期會由一天24小時變為一天只有18小時。之前研究結果顯示 LWD1/2 會在維管束大量表現，由於目前對於維管束生物時鐘之運轉機制所知甚少，因此我們希望能進一步研究 LWD1/2 與維管束生物時鐘間的關係。 為了解 LWD1/2 在維管束中表現是否與其功能相關，我們將此兩種基因接上只會在維管束或葉肉細胞中表現的啟動子，轉殖入 lwd1 lwd2 雙突變株中進行互補試驗 (complementation test)；藉由觀察生物時鐘週期是否從 18 小時恢復為 24 小時，以了解這兩個基因的作用位置及功能。由實驗結果來看，我們發現不論是單獨在維管束或是葉肉細胞中表現 LWD1 或 LWD2 基因，皆會影響到阿拉伯芥的生物時鐘，整棵植株表現出的綜合週期，介於野生型 24 小時與 lwd1 lwd2 雙突變株 18 小時之間。這個結果顯示，不同組織之間的生物時鐘可能不會互相影響；而 LWD1/2 雖於維管束中有較高的表現量，但仍需要在葉肉細胞表現才能具備完整功能。

在模式植物──阿拉伯芥（Arabidopsis thaliana）中，AtYAK1（Arabidopsis thaliana Yak1-related protein kinase）是目前發現唯一屬於DYRK（Dual specificity Yak1-Related protein Kinase）的蛋白激?。雖然之前研究已證明，不同物種之DYRKs 和細胞的生長與發育過程有關。然而，其在植物中的生理功能卻尚未被明確地研究報導過。在先前的研究中，為瞭解AtYAK1 在阿拉伯芥內作用之位置，前人選取AtYAK1 基因ATG 上游約2.5 kb 的序列（Upstream Element, 2.5KUSE）建構至一含有GUS（β-glucuronidase）報告基因的質體中，並轉形至阿拉伯芥，進行GUS 組織染色分析。但在初步結果中，並沒有在轉殖株觀察到明顯的GUS 表現。進一步分析，我們發現在2.5KUSE 序列末端約0.5 kb 的5’非轉譯區（5’untranslated region, 5’UTR）中，有四組開放讀序框（Upstream Open Reading Frame, uORF）。有趣的是，許多研究也顯示，uORFs 會影響轉譯過程中的再起始（re-initiation）作用而調控該基因的表現。另一方面，前人亦透過構築好的2KUSE 轉殖株（即不含有5’UTR）進行上述GUS 實驗。結果發現，此2KUSE 轉殖株的GUS 表現非常顯著。本實驗即要瞭解AtYAK1 的uORFs 是否也會影響其蛋白質的合成。首先，我們以點突變的方式將四組uORFs 中之ATG 換成TTG，目的為構築不含有uORFs 之5’UTR（mutated uORFs, ΔuORFs）。在進行原生質體短暫表現分析法（protoplast transient assay）及GUS 組織染色分析後，將結果與含有uORFs 的結果作比較：當缺乏uORFs 後，其3’端報告基因的表現量確實比原來顯著。綜合以上，我們認為此uORFs 對於AtYAK1 蛋白質之表現佔有相當重要的影響地位。最後，我們對5’非轉譯區是否存在開放讀序框進行阿拉伯芥全基因組分析，相關結果亦於本研究報告中分析討論。AtYAK1（Arabidopsis thaliana Yak1-related protein kinase）is the first DYRK（Dual specificity Yak1-Related protein Kinase ） family member identified in the model plant ─ Arabidopsis thaliana and exists as one copy gene in Arabidopsis. Previous studies showed that many eukaryotic DYRKs are involved in regulating the growth and development of cells. However, the study of AtYAK1 in Arabidopsis is lacking to date. In order to understand where AtYAK1 expresses and functions in plants, a 2.5 kb fragment which is located upstream from the major ATG of AtYAK1（termed Upstream Element, 2.5KUSE）was previously constructed to drive the expression of a reporter gene, GUS（β-glucuronidase）, in transgenic Arabidopsis. Much to our surprise, no GUS expression signal could be detected in such transgenic plants. When further analyses were performed, we found that there are four upstream open reading frames （uORFs） in the 5’untranslated region ( 5’UTR ) within the 2.5KUSE. Many studies indicating that the uORFs can regulate the translation of downstream ORF encoding the major gene product through the procedure of translation re-initiation. This action represents a mode of translational regulation for gene expression. Indeed, GUS activity could be readily detected in transgenic plants expression 2KUSE::GUS, a construct lacking the 5’UTR of AtYAK1. In this study, I have tried to elucidate whether the uORFs of AtYAK1 can regulate the translation of the downstream major ORF. First, in order to construct a 5’UTR fragment of which uORFs have been mutated（ΔuORFs）, we apply site-directed mutagenesis to substitute ATG with TTG for the four uORFs and examine the expression of GUS driven by this mutated 2.5KUSE. After analyzing the results in both Arabidopsis protoplast transient assay and transgenic Arabidopsis, stronger expression of reporter genes in both systems were observed when the four uORFs were mutated. We have also confirmed that, in transient expression system, the increase of reporter gene activity was not due to the excess accumulation of the corresponding mRNAs. Rather, it is the four uORFs which play an important role in negatively regulating the translation of AtYAK1, possibly via inhibiting the translation re-initiation of major ORF. A genome-wide examination of uORFs in all Arabidopsis genes was also performed to assess the possible contribution of uORF in regulating gene expression.

此項研究是用溶氧計連續偵測培養液中之溶氧量，藉以分析固氮\r 單胞藻RF-1 的光合韻律。實驗的結果清楚地看出RF-1 之光合韻律，\r 而且能夠清晰地觀察到其中光合作用、呼吸作用和固氮作用之間的相\r 互關係。研究中還發現：在不進行光合作用時，RF-1 的固氮作用也\r 會停止；另一方面，在有進行光合作用、但是停止固氮作用的狀況下，\r RF-1 光合作用之韻律現象會喪失。這些實驗結果值得未來更深入地\r 探討。報告中也包括了單胞藻PCC6803 的光合韻律實驗，藉以做為\r 有固氮能力與沒有固氮能力藍綠藻之間的對照。The variation of dissolved oxygen (DO) in the culture of the\r unicellular nitrogen-fixing cyanobacterium Synechococcus RF-1\r under diurnal light/dark condition was detected automatically by DO\r meter. The results indicated that the algae exhibited circadian\r photosynthetic rhythm. The results also revealed that a respiration\r rhythm occurred at dark phase when the culture was grown in\r nitrogen-free medium. There was correlation between the rhythm of\r photosynthesis and nitrogen fixation. The nitrogen-fixing activity\r could not be detected if the photosynthesis was stop by cultivated\r under continuous darkness. On the other hand, the rhythm of\r photosynthesis could not persist when the nitrogen-fixing activity\r was inhibited by NaNO3. In order to compare the difference\r between Synechococcus RF-1 and the cyanobacterium, which\r cannot fix nitrogen, the DO pattern of Synechocystis PCC6803 was\r also investigated.

本研究針對台灣產水生植物，蓴菜之構造與生長環境、蓴菜對腸胃道常見致病細菌之抑菌效果以及主要成分暨化合物分析。由本研究結果得知，崙埤湖內之稀有浮葉型水生植物蓴菜，其生長環境為無汙染之乾淨偏酸性水源，最適合生長之生深為50-160 ㎝；水溫則為22-25℃；而蓴菜之地下根莖對表皮金黃葡萄球菌（Staphylococcus aureus）具有輕度之抑菌效果，經由分離純化得知為BS-1：沒食子酸（Gallic acid）；另外，由蓴菜之葉片分離出十種成分分別為BS-2 （Kaempferol-7-O-Glucosids）、BS-3 （Quercetin-7-O-glucosids）、BS-4（5,8,4’-Trihydroxyflavone-7-O-glucosids）、BS-5 （3,5,8,3’4’-Pentahydroxy flavone）、BS-6（Vitamin E: d-Tocopherol）、BS-7 （Glyceride）、BS-8 （Phenolic A）、BS-9（Quercetin）、BS-10（Kaempferol）、BS-11（Phenolic B）。其中發現BS-8 對神經膠腫瘤細胞株有18.42%之抑癌效果，另外，BS-2、BS-3、BS-5、BS-10、BS-11 等成分，呈現良好之美白作用。This investigation is to analyze Brasenia schreberi Gmel., a native rare floating water plant in Taiwan, focusing on the plant’ s structure, its growth environment and, most importantly, the effect of chemical compounds it produces on restraining the common pathogenic bacteria in human stomach. The result indicates that the most suitable growth environment for Brasenia schreberi Gmel. is in slightly acid, pollution-free water such as that in the lake Lung Pi in northern Taiwan. The ideal water depth for its growth is 50-160 cm, and the water temperature is 22-25°C. The impractical BS-1 (Gallic acid) extracted from the izome of Brasenia schreberi Gmel. by separation and purification has a light effect on restraining Staphylococcus aureus, a bacteria in the stomach. From the epidermis of the blade of Brasenia schreberi Gmel., ten other ingredients are also isolated, including BS-2 (Kaempferol-7-O-glucosids), BS-3 (Quercetin-7-O-glucosids), BS-4 (5,8,4’-Trihydroxyflavone-7-O-glucosids), BS-5 (3,5,8,3’,4’-Pentahydroxyflavone), BS-6 (Vitamin E: d-Tocopherol ), BS-7 ( Glyceride ), BS-8 (Phenolic A ), BS-9 (Quercetin), BS-10 (Kaempferol),and BS-11 (Phenolic B). BS-8 is found to resist cancer C6 ( Glioma ) by 18.42%, while BS-2,BS-3, BS-5, BS-10, and BS-11 show an outstanding effect on skin-whitening.

蓮花效應是指蓮葉表面具有奈米纖毛結構，因此只要葉面稍微傾斜，水珠就會滾離葉面，在我們生活週遭，許多植物具有蓮花效應。本實驗選擇彩葉山漆莖作為研究材料，因為我們發現在同一植株上，嫩葉的蓮花效應最佳，而老葉幾乎無蓮花效應。當彩葉山漆莖的新葉轉為老葉，蓮花效應會減弱，甚至消失。我們以不同水量、土壤酸鹼值及光照作為變因，來探討蓮花效應改變的原因，結果發現水量並非主要影響蓮花效應改變的變因；土壤過酸或過鹼，會減弱新葉及嫩葉的蓮花效應；置於暗室則使整株彩葉山漆莖所有葉面皆無蓮花效應。許多植物的性狀，在老化或面臨環境改變時，會將控制性狀的基因開啟或關閉。因此，我們推論，當環境因子改變時，植物的蓮花效應可能是經由基因層次的調控，藉以增強或減弱此性狀的表現。如果不是基因的開啟或關閉，則有可能僅是葉表面的結構發生些微的改變，真正詳細的機制仍有待進一步的確認。;We choose Breynia nivosa (Bull ex W. G. Smith) Small as a model plant to study the lotus effect on the leaves for the reason that on the same chosen plant the new-born leaves have the best lotus effect while the elder ones have little lotus effect. When the new leaves turns into elder ones, the lotus effect also turns weaker or even vanishes. To explore the exact mechanisms, we take water quantity、soil pH、and light density as the experimental factors. The results show that water quantity cannot affect the lotus effect on all leaves, change in soil pH can decrease the lotus effect on the new and new-born leaves, and dark treatments can eliminate the lotus effect on all leaves. When the environments change, the phenotypes of plants could also be changed to adapt to the new conditions by turning on or off genes. Therefore, we suggest that the lotus effect on the leaves is also controlled by genes to increase or decrease its phentype so as to adapt to the changing environments. If not, it may simply be a little change of the surface structure of the leaves. The detailed mechanism remains to be confirmed further.

The objectives of this study were to investigate (1) the floral biology of Jatropha curcas Linn. as well as its possible pollinators, (2) the correlation between the number of pollen on stigma and the frequency of floral visitors, (3) the attractiveness of essential oil extracts from three species of Lamiaceae, i.e. Hyptis suaveolens, Plectranthus ambonicus and Orthosiphon aristatus, to Apis florae, (4) the repellent effect of crude extracts from three species of Graminae, i.e. Imperata cylindrica, Eleusine indica and Dactyloctenium aegyptium, on Polyphagotarsonemus latus, and (5) the effect of appropriate combination between lamiacean essential oil and graminaceous crude extract on the percentage of fruit setting and insect pest protection. \r Jatropha curcas is monoecious plants with tiny male and female flowers borne on the same paniculate cyme. One plant produces 15-30 inflorescence. Each inflorescence composes of 70-120 florets, and only 4-8 florets are successfully setting fruits. Each flower takes approximately 17 days in developing from floral bud till floral opening. The appropriate time for pollination is from 09.00 am to 10.00 am. While bees, wasps, hornets, flies and dragonflies are its potential pollinators, mites, aphids and worms are its harmful insect pests. \r Three volumetric, 1, 3, 6 and 9 ml, of each essential oil extracts were separately sprayed on each observed inflorescence. According to the experiment, 6 and 9 ml of each of the essential oil extracts give similar effective outcome, However, The H. suaveolens extract at 6 ml is the most effective attractant for A. florae. because it uses less of the oil extracts.\r Four concentrations, 0.1 %, 0.5 %, 1.0 %, 1.5 % and 2.0 % of each of the crude extracts from three graminaceous plants were sprayed on each tested plants separately. Concentations above 1.0% consistently provided an effective biocidal activity against Imperata cylindrica , however 1.0% is accecptable. because it uses a reduced level of the crude extracts\r The combination of H. suaveolens’s essential oil and I. cylindrica crude extract both significantly enhanced fruit setting of J. curcas and protected the plant from Polyphagotarsonemus latus without adverse effect on its pollinators.