Academic literature on the topic 'Pak choi (Brassica chinensis L.)'

Ramnarain YI, Ori L, Ansari AA. 2017. Evaluation of the use of vermicompost on the crop production of two varieties of Pak choi (Brassica rapa var. chinensis) and on the soil structure in Suriname. Asian J Agric 1: 73-79. The present research was carried out from January to May 2016 at the Anton de Kom University of Suriname, Paramaribo. The investigation consisted of a field and laboratory study in order to evaluate the effect of vermicompost on crop production of 2 varieties Brassica rapa var. chinensis, white and green Pak choi, nutrient availability in the soil after the use of vermicompost and nutrient value of the crop.The experiment was carried out (completely randomized design) in a greenhouse for six weeks. The treatments were vermicompost (V), cow manure (S), chemical fertilizer (K) and control (C). Plant growth parameters were recorded during the experiment (plant height and number of leaves) and after harvest (root and shoot biomass, leaf area). Nutrient analysis (Ca and Fe) of Pak choi was also conducted followed by pre and post-experiment soil analysis (pH, EC, TOC, N, P, K and C/N ratio). The results were collected and analyzed using Sigma Plot 12.0 tools. In the white Pak choi the number of leaves, root length and weight of fresh plants showed no significant differences among the four treatments using Tukey’s test (P≤0.05). In the green Pak choi the number of leaves and root length showed no significant differences among the four treatments by Tukey’s test (P≤0.05). Furthermore, the soil parameters (pH, OC, N) did not indicate a significant increase or decrease of the elements in the soil. P did decrease significantly and K increase in the treatments in the soil was not relevant.The evaluation of the use of vermicompost on the crop production of 2 varieties of Pak choi (Brassica rapa var. chinensis) proved that the plants treated with vermicompost had similar results as those treated with cow manure and chemical fertilizer.

Using fish culture water and sludge may benefit vegetable production by reducing the need for high-quality irrigation water in areas where water is a limiting resource for agriculture. Fish water and sludge contains nutrients, thereby reducing the need for chemical fertilizers. A study was conducted to integrate fish (tilapia) culture with field production of Pak choi (Brassica rapa L. Chinensis). Water from tilapia culture tanks from which solids were removed (SR) and from tanks with no solid removal (NR) were applied to pak choi 2 to 3 times weekly through a drip system. These treatments were compared with sludge (FS) removed from culture tanks using three methods of irrigation. Conventional methods of fertigation (F) and band fertilizer (B) application were included as control treatments. The trial was conducted for 2 seasons. In the first season, pak choi applied with (FS) produced total yields ranging from 21 to 26 t·ha–l. Pak choi applied with fish water from tanks with (SR) and (NR) produced yields of 19 and 20 t·ha–l, respectively. Pak choi grown with (F) and (B) applications yielded 21 and 20 t·ha–l, respectively. There were no significant yield differences between the (FS) treated and (F) plots. Yield from (FS) treatment was significantly higher than all other treatments except (F). Similar results were obtained during the second season, but total yields from various treatments were 50% higher than the first season. Fish culture water and sludge are therefore good alternative sources of irrigation and fertilizer for pak choi.

ABSTRAKLimbah ampas tahu dapat menyebabkan pencemaran lingkungan. Selama ini limbah ampas tahu kurang dimanfaatkan secara maksimal. Padahal, limbah ampas tahu memiliki kandungan protein yang cukup tinggi serta senyawa-senyawa yang berpotensi untuk meningkatkan kesuburan tanah dan tanaman. Penelitian ini bertujuan untuk mengetahui pertumbuhan tanaman pak choi dengan menggunakan variasi komposisi limbah ampas tahu serta untuk mengetahui kandungan NPK yang terdapat dalam limbah ampas tahu. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) dengan komposisi limbah ampas tahu masing-masing 25%, 50%, 75% dan 100%. Kontrol positif pupuk kandang dan kontrol negatif tanah. Parameter yang diukur pada tanaman pak choi, yaitu jumlah daun dan berat basah tanaman. Analisis data diperoleh dengan menggunakan uji Analisis Varians dan dilanjut dengan uji Beda Nyata Terkecil (BNT) untuk parameter jumlah daun sedangkan uji Wilayah Berganda Duncan (DMRT) digunakan untuk parameter berat basah. Berdasarkan uji statistik yang telah dilakukan menggunakan uji BNT untuk jumlah daun dan uji DMRT untuk berat basah menunjukan bahwa ada perbedaan yang signifikan diantara variasi komposisi limbah ampas tahu, dalam hal ini komposisi limbah ampas tahu 100% yang paling efektif dalam mempengaruhi pertumbuhan tanaman pak choi. Hasil penelitian menunjukan kandungan unsur N,P,K limbah ampas tahu kering ditinjau dari kriteria unsur N tercatat rendah, yaitu 0,110% sedangkan unsur P dan unsur K tercatat sangat tinggi, yaitu 1,219% dan 0,361%.

The processing of organic wastes and composts by worms results in castes and vermiliquer (i.e., vermicompost leachate). Both castes and vermiliquer contain plant available nutrients, the latter better suited to hydroponic operations, but the optimum pH for worm productivity and vermiliquer production makes the latter too alkaline for hydroponics. We show that under optimal hydroponic management practices, the growth and yield of pak choi (Brassica chinensis) based entirely on pH buffered vermiliquer collected after 8–10 weeks of vermicomposting was comparable with those treated with a conventional inorganic hydroponic fertiliser. Nitric acid proved to be a superior pH buffer compared with orthophosphoric acid. The total fresh weight in the nitric acid buffered vermiliquer treatments ranged from 70% to 98% of the total fresh weight of the control. However, the non-buffered hydroponic production of pak choi using off-line (batch) vermiliquer or direct linkage with vermifarms was not successful. There were no statistically significant differences between pak choi yields using vermiliquer from kitchen wastes or composted paunch materials. A 50% dilution of vermiliquer led to yield loss, but less proportionately than the dilution, and the use of pot hydroponics rather than nutrient film technique (NFT) hydroponics led to a better performance of pak choi under less favourable conditions. This is the first report of comparable yields between vermiliquer treatments and an inorganic nutrient source and highlights the feasibility and commercial potential of this hydroponic practice.

Abstract Development of interplanting systems for vegetables has been impeded due to concerns about yield reductions and use of systematic experimental designs that limit analysis of fundamental competitive processes. This study employed an addition series and growth analysis combined with management strategies aimed at minimizing competition between the crop and the interplant. Pak choi [Brassica rapa L. (Chinensis Group)] was interplanted with strips of ryegrass (Lolium perenne L.) that covered 67% of the soil. Pak Choi was a weak competitor compared to perennial ryegrass. Mulch suppression using a sublethal rate of fluazifop provided the most promising management strategy to reduce competition from the ryegrass interplant. Timing of suppression and reduction of mulch root growth were critical elements of successful management. Chemical names used: (±)-2-[4-[[5-(trifluoromethyl)-2-pyrindinyI]oxy]phenoxy]propanoic acid (fluazifop).

Global surface temperatures are predicted to increase by 1 to 4 °C by the year 2100. To unravel the risks from rising temperature to Taiwan’s summer leafy vegetable production, the phenotypical and physiological responses of two leafy crops, pak choi (Brassica chinensis L. cv. Quanzhou) and edible amaranth (Amaranthus tricolor L. cv. White leaf), were compared under an elevated temperature. A temperature increase from 28 to 32 °C resulted in lower leaf calcium, magnesium, and manganese concentrations (dry weight basis) in pak choi without significant changes in shoot dry weight, suggesting potential negative effects of the elevated temperature on pak choi leaf nutrient status. However, increased temperature promoted both root and leaf growth in edible amaranth, which may be beneficial to its yield, making edible amaranth a potential summer leafy vegetable crop for Taiwan. Furthermore, a temperature change from 28 to 32 °C resulted in a higher leaf nitrate concentration in edible amaranth, because of the lower nitrate reductase activity (NRA). Thus, suitable nitrogen fertilization rates and programs under elevated temperature conditions should be reconsidered in the future. To sum up, a future rise in summer temperatures may impose negative impacts on pak choi leaf nutrient status but positive impacts on edible amaranth production.

Methanethiol (MT) is a volatile compound responsible for the unpleasant odor evolved when fresh broccoli (Brassica oleracea L., Italica group) is held under anaerobic conditions. Inductive atmospheres can develop in storage, transportation containers, or modified atmosphere packages, resulting in reduced quality. To determine if related vegetables are capable of producing MT, 12 different vegetables from the genus Brassica were cut into ready-to-eat forms. Fifty-gram samples were sealed in 500-mL glass jars and flushed with N2. After 24 h in the dark at 20 °C, headspace samples from the jars were analyzed for MT and other volatiles. Headspace concentration of MT was greatest in broccoli florets, followed by pak choi (Brassica rapa L., Chinensis group) leaf blades, savoy cabbage (Brassica oleracea L., Capitata group), broccoflower (Brassica oleracea L., Botrytis group), and green and red cabbage (Brassica oleracea L., Capitata group). Broccoli stems, kale (Brassica oleracea L., Acephala group), Brussels sprouts (Brassica oleracea L., Gemmifera group), pak choi petioles, rutabaga (Brassica napus L., Napobrassica group) root, cauliflower (Brassica oleracea L., Botrytis group) florets, Chinese cabbage (Brassica rapa L., Pekinensis group), and kohlrabi (Brassica oleracea L., Gongylodes group) tubers produced <3% of the MT produced by broccoli florets. Green tissues appeared to have a greater capacity to produce MT than nongreen tissues. Anaerobic production of CO2 and ethanol did not relate to the vegetable's ability to produce MT. The production of dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) were also induced by the anaerobic conditions. Green cabbage produced the greatest concentration of DMDS, followed by savoy cabbage and broccoli florets. Production of DMTS was similar to the pattern observed for MT, but DMDS production was not highly correlated with MT production.

Cold-tolerant, Ogura male-sterile, somatic hybrid rapeseed (Brassica napus L.) lines were used as maternal parents in two independent introgression experiments. In one experiment, an atrazine-sensitive B. napus (aacc) somatic hybrid was crossed directly with a male-fertile pak choi (B. campestris Chinensis Group, aa) accession. Allotriploid (sac) progeny were then backcrossed to the recurrent pak choi parent. Forty-five percent of the progeny from the first backcross were determined to be diploids (aa). In the other experiment, an atrazine-resistant B. napus somatic hybrid was crossed first to a bridge line. Three additional backcross generations to Chinese cabbage (B. campestris Pekinensis Group) resulted in Chinese cabbage resistant to black rot (Xanthomonas campestris pv. campestris). These materials may be useful for production of B. campestris hybrid vegetable seed.

MP significantly reduced Cd accumulation in the shoots of pak choi in comparison to the control, in consecutive growing seasons, and the minimum Cd contents were less than the maximum permitted level proposed by the Codex Alimentarius Commission.

The overall aim of the study was to assess the risk of gene flow from Brassica crops by insectmediated pollen transport. I measured the viability of pollen in Brassica flowers throughout crop development and compared this with the viability of pollen transported by insects inside and outside one early- and one late-season crop. In order to evaluate the relative importance of different species in pollen transport, I measured abundance of flower visitors during crop development, and measured the foraging behaviour of five key pollinator species throughout the growing season, in relation to variation in microclimate, crop phenology and the relative abundance of other pollinator species competing for flower resources. Flower visiting insects of Brassica rapa crops were highly diverse, and their abundance and diversity changed with crop phenology. I found similar abundances at the family level for both crops studied, although capture rates were greater in the early- than in the late-season crop. Across flowering development, the greatest numbers of insects were captured at the peak of flowering for both crops. During the flowering period, Diptera was the most abundant order collected, followed by Hymenoptera. The most abundant family in Hymenoptera was Apidae which tracked crop development in both fields, with greater numbers of insects captured inside than outside the field. Standardized-count pollen loads were smaller in Diptera than in Hymenoptera. Of the five key pollinator species sampled, Lasioglossum sordidum (Hymenoptera: Halictidae), Apis mellifera (Hymenoptera: Apidae) and Bombus terrestris (Hymenoptera: Apidae) transported similar pollen loads, which were much greater than those carried by Eristalis tenax (Diptera: Syrphidae) and Melangyna novae-zealandiae (Diptera: Syrphidae). The numbers of insects captured outside of the crop were 10% and 33% of the totals captured inside for the early- and the late-season crop, respectively. The proportion of insects entering versus leaving the crop varied considerably across species, crops and trap location (i.e., whether traps were inside or 50 m outside the border of the crop). However, it is worth noting that not uncommonly more insects were attracted into the crop early in the season, staying there rather than leaving, and then when flowers started to disappear there was a massive escape of insects leaving. This research provides evidence for the influence of crop age on the foraging behaviour of key pollinators and for species-specific variation in the foraging behaviour of Brassica visitors with crop development. Temporal variation in the rate and variability of movement between flowers, and the duration and variability in time spent on each flower, throughout the growing season differed markedly between pollinator species. Flower density, plant density, and the abundance of other insects contributed to the observed variation in pollinator behavioural activity for A. mellifera, E. tenax, M. novae-zelandiae and L. sordidum. Bombus terrestris had the greatest rates and variability of movement, and the greatest rates of flower visitation among all key pollinators studied. Therefore B. terrestris might contribute to gene flow to a greater extent than other key pollinators. Additionally B. terrestris had the greatest variability in the rate of movement, increasing the risk of pollen movement over long distances. In summary, I found that (i) insect abundance and diversity changed with crop phenology and Diptera was the most abundant order collected, (ii) flower density, plant density, and the abundance of other insect pollinators were important factors explaining pollinator behaviour for all key pollinators, except B. terrestris, (iii) B. terrestris might contribute to gene flow to a greater extent than other key pollinators, because it has a greater rate of flower visitation and a greater flight distance between flowers than other pollinators, and (iv) pollen viability tended to decrease with crop development and declined sharply even just 50 m outside the edge of the crop.

碩士
國立中興大學
園藝學系所
101
Pak-Choi is one of the most important leafy vegetables in Taiwan. Pak choi is easy and fast to grow which makes it an ideal vegetable for summer season. It can be grown all year round in Taiwan. Utilization of Pak-choi as bioreactors not only can produce high economic product and increase the additional values, but also can take advantage of its cultural characteristic to produce large amount of target protein for industry, food, forage, and medical application. Transglutaminase (TGase) can catalyze the formation of ε-(γ-glutamyl) lysine covalent bond within molecules and between molecules and form 3D structure by cross link between proteins. On the basis of the gelatinize ability of protein concentrate, TGase has great application potential in food industry. Expression of target genes via chloroplast genomes not only enhances the level of expression without epigenetic effects, but also prevents out crossing of the introduced target genes via pollen grain. In this study, chloroplast transformation vectors harboring the selective marker gene (AlaR, daao, and aadA) and target genes (tga, gus, and egfp) constructed outside and of homologus recombination sequences, respectively, were transferred into the chloroplast of Pak-Choi via biolistic bombardment. After occurring twice of DNA recombination with chloroplast genome, only target gene will remain in the chloroplast genome and the selective gene and vector residues will be eliminated. The purpose of this study is to develop selective maker gene-free technique of Pak-choi chloroplast transformation for the production of TGase. In this study, 4 vectors pMT91EP-sRA, pMT91EP-sDA, pMT92GP-sDA, and pMT92GP-sRA, harboring the tga gene were transferred into the chloroplast of Pak-Choi ''Tainung No.3'' via biolistic bombardment. The regenerated plantlets were primary selected by 100~200 ppm D-alanine or 25~50 ppm spectinomycin. T0, T1, and T2 trasplastomic Pak-Choi plants were obtained from pMT91EP-sRA and pMT92GP-sRA constructs. The results of PCR, RT-PCR and western blots analyses indicated that the tga gene was integrated in the chloroplast genome of transplastomic Pak-Choi and expressed tga mRNA as well as TGase protein, while selective marker genes, AlaR, and aadA, were not detectable in the transplastomic Pak-Choi. Our results showed that the possibility of production of tga gene transplastomic Pak-Choi with maker gene-free technique.

博士
國立中興大學
園藝學系所
94
The objectives of this study were to: 1. develop an in vitro tissue regeneration system for Pak-choi (Brassica campestris L. ssp. chinensis L. Makino), 2. explore the possibility for improving the in vitro tissue regeneration derived from mature or aging explants of Pak-choi, 3. establish the Agrobacterium transformation system of Pak-choi, 4. establish the gene-gun transformation system of Pak-choi, and 5. explore the possibility for improvement of Pak-choi with stresses resistance via Agrobacterium-mediated and gene-gun transformation. The sources of explants of Pak-choi and the components of culture medium were studied to develop a tissue culture system for Pak-choi. The results indicated that the MS basal medium (Murashige and Skoog, 1962) supplemented with 2% sucrose, 1 mg/L BA, 0.5 mg/L NAA, 0.25mg/L GA3, 3mg/L AgNO3 and 5mg/L putrescine was the best components of culture medium for the explants regeneration of ''Tainung No. 1'' and ''Tainung No. 2'' Pak-choi, and 66.7% to 70% of regeneration rate could be achieved. Higher regeneration rates were obtained from the explants derived from the cotyledons than those of from hypocotyls. In general, calli were first regenerated from the explants of Pak-choi, and then adventitious shoots and roots were regenerated on the regeneration medium subsequently, ie. via “organogenesis pathway”. However, embryoids rather than calli were regenerated on the regeneration medium supplemented with polyamines (e.g. putrescine or spermidine), ie. via “somatic embryogenesis pathway”. The effects of types, ages, and positions of explants of ''Tainung No. 1'' and ''Tainung No. 2'' Pak-choi on in vitro tissue regeneration were performed. Effects of plant growth regulators, amino acids, polyamines, casein hydrolysate, and silver nitrate on shoot regeneration and root formation derived from the 15-days-old and 21-days-old explants of Pak-choi was also conducted. The highest rates of shoot regeneration and root formation were found in the 3-days-old explants. As the ages increased, the rates of shoot regeneration and root formation decreased. However, the high differentiation capacity was also found in the 27-days-old explants. Significantly increased the rates of shoot regeneration and root formation was found in the 15-days-old explants cultivated in the regeneration medium of Pak-choi (MS basal medium containing 2% sucrose, 1 mg/L BA, 0.5 mg/L NAA, 0.25mg/L GA3, and 3mg/L AgNO3) supplemented with 50 ml/l coconut juice. Improving the in vitro tissue regeneration of 21-days-old explants could be achieved by addition of 0.1 mg/L ABA into the regeneration medium of Pak-choi. Nevertheless, the efficient regeneration medium for 27-days-old explants was the same culture medium as the 3-days-old and 9-days-old explants.Attempts had been made to co-transfer the superoxide dismutase (sod62), and catalase (cat78) genes of Chinese cabbage into the ''Tainung No.1'' and ''Tainung No.2'' Pak-choi. Cotyledon and hypocotyl explants of Pak-choi were co-infected with two Agrobacterium carrying a distinct disarmed T-DNA containing rbcS-sod62 (pKrScn) and rbcS-cat78 (pKrCcn) genes, respectively. Results indicate that regenerated rates of Pak-choi were 16%. After 20 mg/L of kanamycin selection, the survival rate was 1.6%, and co-transformation rate of two genes was 0.075%. The results of PCR and Southern bolt hybridization indicated that the rbcS-sod62 and rbcS-cat78 genes had been transferred into Pak-choi, and inserted into their genomes. Two co-transformed plants of ''Tainung No.2'' Pak-choi were obtained. Increases in the transformation efficiency were obtained in the co-culture medium supplemented with the emery or 200µM acetosyringone (AS). Cotyledon and hypocotyl explants of Pak-choi were co-infected with two Agrobacterium carrying a distinct disarmed T-DNA containing rbcS-TP-sod62 (pKrTScn) and rbcS-TP-cat78 (pKrTCcn) genes, respectively. Results indicate that regenerated rates of Pak-choi were 18%. After20 mg/L of kanamycin selection, the survival rate was 2.2%, and co-transformation rate of two genes was 0.202%. The results of PCR and Southern bolt hybridization indicated that the rbcS-TPsod62 and rbcS-TPcat78 genes had been transferred into Pak-choi, and inserted into their genomes. Two and four co-transformed plants of ''Tainung No.1'' and ''Tainung No.2'' Pak-choi were obtained, respectively. T0 plants of rbcS-TP-sod62 and rbcS-TP-cat78 genes transformed Pak-choi were allowed to self-pollinated, and seeds were collected at maturity. T0 seeds were germinated on MS medium containing 20 mg/L of kanamycin for two weeks. Survival T1 seedlings were subjected to PCR and Southern bolt hybridization analysis. The results of genetic analysis indicated that the transformed rbcS-TP-sod62 and rbcS-TP-cat78 genes had been stably inherited in T1 progeny plants. Significant higher SOD and CAT activities were detected in the T1 transgenic progeny of Pak-choi than those of control plants. Following settings were suggested when Pak-choi explants was bombarded with Biolistic PDS-1000/He (Bio-Rad) particle gun apparatus: gold particle size less than 1.0 μm in diameter, 4mm spacer ring in thickness, 4mm spacer bar in diameter, 4.5cm for distance of bombardment, 3cm for distance from microcarrier launch assembly to the recipient explants. High transformation efficiency was achieved from the 6-days old Pak-choi explants bombarded with 650psi~900psi rupture disks. Cotyledon and hypocotyl explants of Pak-choi were bombarded with two plasmids containing sod62 (pASCCSOD) and cat78 (pASCCCAT) genes, respectively. After 10 mg/L of spectinomycin selection, the survival rate was 3.86%, and co-transformation rate of two genes was 0.43%. The results of PCR and Southern bolt hybridization indicated that the sod62 and cat78 genes had been transferred into Pak-choi, and inserted into their genomes. Two and twenty-nine co-transformed plants of ''Tainung No.1'' and ''Tainung No.2''Pak-choi were obtained, respectively. T0 plants of sod62 and cat78 genes transformed Pak-choi were allowed to self-pollinated, and seeds were collected at maturity. T0 seeds were germinated on MS medium containing 10 mg/L of spectinomycin for two weeks. Survival T1 seedlings were subjected to PCR and Southern bolt hybridization analysis. The results of genetic analysis indicated that the transformed sod62 and cat78 genes had been stably inherited in T1 progeny plants. Significant higher SOD and CAT activities were detected in the T1 transgenic progeny of Pak-choi than those of control plants.

碩士
國立中興大學
土壤環境科學系所
99
Phosphite (HPO3-2, Phi) is a reduced form of phosphorus, having a similar structure to phosphate (PO4-3, Pi). The former is a diprotic acid, but phosphate is a triprotic acid. Phosphite salts have been used as a fungicide for some diseases control. Some plants can used it as phosphorus fertilizer, but no phosphorus fertilizer effect for other plants, after the long-term use it even caused ecological problem. This study using hydroponic system to investigate the effect of phosphite/phosphate ratio in the nutrient solution on the growth, nitrate reductase, phosphatase, nutrient uptake of Pak-choi (Brassica chinensis L.,Cultiva). Screening Phi using bacteria from soil and inoculated into nutrient solution to evaluate their effect on the growth of Pak-choi. Results showed that increased the phosphite/phosphate ratio in nutrient solution decreased weights of shoot and root in fresh and dry, concentrations of extractable phosphate, total phosphorus, and magnesium, activities of leaf nitrate reductase and phosphatase, and the chlorophyll index. Evidence showed phosphate contributes a partial function as phosphorus fertilizer. Although the fresh weight and dry weight of Pak-choi root of 100％ phosphate treatment was 56 %, and 67 % decreased, respectively, compared to no phosphorus treatment. The fresh weight and dry weight of Pak-choi shoot was 69 % and 9 % increased, respectively, compared to the no phosphorus treatment. The inoculation of the top three most effective phosphate using bacteria, increased the Pak-choi shoot and root fresh weights by 37-93 % and 27-62 %, respectively, compared to no inoculation treatment

碩士
國立中興大學
園藝學系
92
Abstract The objectives of this study were to evaluate the feasibility of using medium film culture techniques in automatic conveyer system for short season vegetable production. ‘San-Feng’ pak-choi (Brassica campestris L. Chinensis Group) was used as plant materials and peat moss (PM), golden mushroom compost (GMC), rice hull (RH), and perlite (PR) as soilless mediums. Media either from commercial or from self-designed formulas were tested in different thickness for pak-choi growth. Results indicated that as the material Florafleur-001H medium thickness decreased from 3 cm to 1 cm, medium temperature, electrical conductivity (EC) increased, and leaf turgor decreased also during the early growth stage. Plant heights, stem diameters, leaf numbers, leaf sizes, and dry weights were decreased significantly also as medium thickness decreased. The best yields of 3.70 kg/m2 was obtained on the medium thickness at 3 cm. Since the air filled porosity (AFP) of mediums decreased from 10% to 14.9% at 1 cm thick. This caused great inconvenience in cultivation management. Commercial medium amendment by adding 10~30% of RH or 20~40% of PR could increase AFP by 1.5% to 2.5%. Among the physical characteristics analysis of GMC, PM, RH, PR, and soil, the container capacity (CC) of GM and PM were 58-67% and 67-77%, respectively, and were significantly higher than all other materials. As the height of container increased, CC decreased, AFP increased. Although the easily available water (EAW) content was not significant different among tested medium materials, the EAW of all materials in taller containers were found higher than those in shorter one. In the contrary, the water buffer capacity (WBC) in shorter containers was significantly less than that of taller containers. RH and PR had the highest portion of particle size above 2 mm thus had the highest AFP at 80-86% and 44-51%, respectively. Three different medium formulas were designed according to the physical and chemical characteristics of tested medium materials. The best plant growth and highest final yield was obtained from the formula of PM: GMC: RH = 3:2:1 (v/v) which had TP, AFP, CC, EAW, WBC, and BD for 94.7%, 39.6%, 55%, 23.5%, 7.7%, and 0.12g/cm3, respectively.

碩士
國立中興大學
園藝學系
81
Two cultivars of Pak Choi(Brassica campestris L. var. chinensis) ere used to study the physiology and growth of the vegetable cultured in solution with supraoptimal temperatures.

Vermicompost leachate (vermiliquer) is the liquid obtained from frequent washing of worms, organic inputs and casts. It is rich in nutrients for plants. The aim of this study was to evaluate the potential of vermiliquer as an alternative to inorganic nutrient sources in hydorponics.

碩士
國立屏東科技大學
熱帶農業暨國際合作研究所
93
Bamboo vinegar was produced by three to five years old moso bamboo (Phyllostachys pubescens) from Jwu-Shan, the carbonization temperatures each were 400(deg)C, 600(deg)C, and 800(deg)C and the collection temperatures were from 150(deg)C which at least over six months stable sinking and distillation methods and the commercial product D, were prepared to analyze its valid components including the pH value, electric conductivity, and the element contents of phosphorus, potassium, calcium, and magnesium etc. in this experiment. The original vinegar which diluted with distilled water in the concentration of 100, 300 , and 500 times were each foliar spray and direct irrigation treated in field and the commercial culture medium to investigate the effect of moso bamboo vinegar on pak-choi plant (Brassica rapa L. Chinensis Group cv. Feng-Shan Pak-choi). In the foliar spray test of different concentration solution of bamboo vinegar A on pak-choi showed an promotional effect that were 1.4 times in plant weight and 1.1 times in plant height increasing. Foliar spray test by bamboo vinegar solution diluted with distilled water 100 times in four seasons showed that vinegar A and B promoted plant weight of pak-choi each to 2.6 and 4 times increasing in summer period, each 1.68 and 1.61 times increasing in autumn and each 1.48 and 1.40 times increasing in winter, and then each 1.49 and 1.45 times increasing in spring period separately. The direct bamboo vinegar irrigation on commercial medium culture of pak-choi plant showed that vinegar diluted with distilled water under 100 and 300 times concentration solution promoted plant weight each to 1.43 and 1.40 times increasing separately. Direct bamboo vinegar irrigation treatment in field showed that diluted vinegar A and B solution each in the concentration of 500 times could promote to 1.75 and 1.65 times increasing of plant weight in pak-choi separately, while there were 1.5 and 1.55 times increasing of plant weight in the diluted 300 times concentration solution of vinegar A and B each. Moso bamboo vinegar A and B also had the plant weight promoted effect of pak-choi plant in 2.5 times increasing when tested at 100 times diluted solution each.