31,021 research outputs found
Trends of Phalaenopsis orchid breeding research
No full textPhalaenopsis is one of the most popular and improtant orchids produecd at commercial scale. New cultivars are produced by selection of seeding plants during their flowering stage. After selection of orchid plants with desirable traits, tissue culture and mass production of young plantlets were achieved through flower stalk node culture in vitro. Cross hybridization by artificial pollination among different parental hybrids usually can lead to capsule set and seed formation. Howerver, breeding barriers are present in Plalaenopsis and its alliance genera with the mechanisms largely remained unknown. Meiotic chromosome behavior of the pollen mother cells (PMC) was investigated to examine whether it is correlated with seed set in different breeding parents of both Doritaenopsis and Phalenopsis orchids. The results showed that high perecntage of normal tetrad, in addition ot regular bivalent chromosome paring, generally suggests high fertility. Unreduced gametes such as dyads were observed during the PMC meiotic process and the number of the dyads could be increased by treating young flower buds with mitotic inhibitors such as colchicines and trifluralin. Through cross Pollination of chemically conditioned pollinia, chance of obtaining polyploidy seedlings is expected to be increased. Through these meiotic analysis and chemical treatment, breeding efficiency of phalanopsis orchids will be increased
FIGURE 16 in Redefinition of the genus Luciaphorus Mahunka, 1981 (Acari: Pygmephoridae) with redescription of L. perNiciosus Rack, 1983 and L. auriculariae Gao, Zou and Jiang, 1990
No full textFIGURE 16. Luciaphorus auriculariae Gao, Zou and Jiang, 1990, male: A—left leg III in dorsal view, B—left leg IV in dorsal view.Published as part of Khaustov, Alexander A., Shentu, Hsuan & Ho, Chyi-Chen, 2018, Redefinition of the genus Luciaphorus Mahunka, 1981 (Acari: Pygmephoridae) with redescription of L. perNiciosus Rack, 1983 and L. auriculariae Gao, Zou and Jiang, 1990, pp. 536-556 in Zootaxa 4369 (4) on page 552, DOI: 10.11646/zootaxa.4369.4.5, http://zenodo.org/record/113643
(37(1):24-31)A Simple Apparatus for Starch Gel Electrophoresis and its Application in Isozyme Study
No full text本試驗所設計一套簡易澱粉膠體電泳的設備，經試用於同功異構酶的分析，顯示效果良好，經濟可行。文中詳述電泳槽、膠體鑄模及膠體切割的零件及其組合，並討論澱粉膠之製作及電泳條件、染色方法。一些同功異構酶的偵測及其應用亦在本文提出。
A simple starch gel electrophoretic apparatus has been designed for isozyme analysis. After testing some isozymes, it showed good resolution and economic applicability. Methods of assembling electrophoretic tank, gel model and gel slicer were presented in detail. Starch gel making, electrophoretic condition as well as activity staining were also described. The results of detecting some isozyme systems and aspects of their application were mentioned
Cloning of Phytoene Desaturase Gene in Oncidium Gower Ramsey-Orchidaceae and Its Expression Analysis at Different Flower Stages
No full textOncidium Gower Ramsey is an important ornamental orchid in Taiwan. The bright
yellow floral color is due to carotenoid accumulation in the flower tissues. In order to
understand the expression of phytoene desaturase (PDS), a key enzyme for the
biosynthesis of β-carotene, the cDNA encoding PDS was cloned and characterized
during flower development. The full length OgrPDS cDNA contains 2,273 bp, including
1,593 bp open reading frame encoding for a polypeptide of 531 amino acid residues. The
5’ and 3’ untranslated regions (UTR) were 293 and 387 bp, respectively. The deduced
amino acid sequence of this PDS has 72-75 % similarity to PDS from other plant species.
The relative expression level of the OgrPDS in roots and leaves was investigated. The
result showed that the expression level of OgrPDS at different flower developmental
stages increased gradually until stage 5 which two- and three- fold higher than leaves
and roots, respectively
Leaf, stem and crown galls on perennial asters caused by Agrobacterium tumefaciens in Taiwan
No full textLeaf, stem, and crown galls induced by Agrobacterium tumefaciens were observed on field grown perennial asters (Aster spp.). Plants of purple flowers were more susceptible to infection than white flowers. The occurrence ranged from 25% in white flowered and 90% in purple flowered plants. Galls also occurred on leaves wounded by insect bites or mechanical shearing. Agrobacterium tumefaciens was isolated from crown and leaf galls with a selective medium NASA. The bacterial isolate was identified as A. tumefaciens using the Biolog GN system. Inoculation of selected A. tumefaciens strains on Kalanchoe pinnata leaves resulted in gall formation 8~10 days afterward. Several other A. tumefaciens strains from different gall samples also caused gall formation 6~8 days after inoculating on the stems of tobacco, and tomato seedlings. Re-inoculating virulent strains by scissors onto healthy aster leaves also induced galls 10 to 12 days after cut-inoculation. Biochemical tests of most Agrobacterium strains from aster galls showed that they belong to biovar 1
Two new species of Digamasellidae from Taiwan (Acari: Mesostigmata)
No full textMa, Li-Ming, Ho, Chyi-Chen, Wang, Shun-Cheng (2014): Two new species of Digamasellidae from Taiwan (Acari: Mesostigmata). Zootaxa 3768 (1): 43-58, DOI: 10.11646/zootaxa.3768.1.
Application of Electrophoresis in Citrus Breeding
No full text本研究以本省栽培最重要的柑橘--碰柑、桶柑、柳橙、檸檬、葡萄柚和袖子等的幼嫩葉片或成熟葉片為材料，利用電泳分離技術，探討peroxidase (PRX)、esterase (EST)、superoxide dis-mutase (SOD)、glutamate oxaloacetate transaminase (GOT) shikimic dehydrogenase (ShDH)、malate dehydrogenase (MDH)、及phosphoglucose isomerase (PGI)等七種酵素之同功異構酶基因型之差異，做為將來育種上珠心胚苗與有性胚苗鑑定之依據，以提高育種效率。
試驗結果顯示，GOT、PRX及PGI三種酵素的同功異構酶在不同柑橘之間具有差異性，即這些酵素均為多型性，其餘酵素在不同柑橘之間則差異不大或沒有差異。再以柳橙和柚子雜交後代來進行試驗，顯示GOT及PRX可做為分辨珠心胚或有性胚苗的依據。珠心胚苗的GOT及PRX同功異構酶和母本柳橙的一樣，而有性胚苗的PRX很明顯的表示出兩親本的混合型。
控制同功異構酶表現的基因型及其在育種上的應用，將在本文加以討論。
Young leaves from plaits of six important citrus species in Taiwan Ponkan (Citrus reticulata), Tankan (C. tankan), Liucheng (C. sinensis), Lemon (C. limon, Hort. var. Eureka), grapefruit (C. paradisi, Hort. var. Ruby) and Pummelo (C. grandis, Hotr. var. Wentan) were used for analyzing isozyme variation by electrophoresis.
Seven enzymes were studied in the experiment, including peroxidase (PRX) esterase (EST), superoxide dismutase (SOD), glutamate oxaloacetate transaminase (GOT), shikimic dehydrogenase (ShDH), malate dehydrogenase (MDH) and phospho glucose isomerase (PGI).
The purpose of this study was to see if any isoenzyme marker can be used to distinguish zygotic from nucellar seedlings in order to increase breeding efficiency.
The results showed that GOT, PRX and PGI are polymorphic among different citrus species. All other four enzymes were monomorphic.
GOT and PRX had been adopted to distinguish zygotic seedlings in a cross between Liucheng and Wentan pummelo.
Isozyme banding of nucellar seedlings had the same patterns with pistil parent (Liucheng).
Hybrid band of PRX isozymes confirmed a true hybrid in certain tested plantlets.
Genetics of isozymes and their application for citrus breeding program was discussed briefly in the report
Study on Laminar Hydathodes of Ficus formosana (Moraceae) Ⅰ. Morphology and Ultrastructure
No full textAponychus 壹新種及 A . corpuzae 的重新描述
No full textAponychus mallotus n. sp. was collected from Mallotus paniculatus (Lam.) Muell. Arg. in central Taiwan. Aponychus corpuzae Rimando collected from bamboo is redescribed with measurements on dorsal setal length and leg chaetotaxy observed by this author.
臺灣中部在白匏仔（Mallotus paniculatus (Lam.) Muell. Arg.）上採得一新種葉蟎Aponychus mallotus n. sp.。另重新描述作者在竹葉上採得之A. corpuzae Rimando，寫出作者所觀察到的足毛相，並測量背面剛毛長度
Dispersion Statistics and Sample Size Estimates for Tetranychus kanzawai (Acari: Tetranychidae) on Mulberry
No full textDispersion indices were calculated for Tetranychus kanzawai Kishida in groves of mulberry, Morns alba (L.), in Taiwan. These indices indicated a clumped distribution for the surveyed population range of T. kanzawai: 0.53–96.5 mites per leaf. However, the X2 goodness-of-fit test generally rejected the negative binomial model among trees, but accepted it within trees. The level of aggregation varied with the population density of T. kanzawai and among mulberry groves. The dispersal of spider mites is discussed as a factor affecting this parameter. Optimal sample size is estimated for various densities of T. kanzawai and error margins on the assumption of Taylor's power law and mean crowding-mean regression
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