• Journal of Plant Biology
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• 제9권1_2호
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• pp.17-21
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• 1966

The mutual relationships of boron, Ca and sucrose were studied in relation to in vitro pollen growth and pollen bursting, by using conventient pollen from Crinum asiaticum for experiment. Crinum pollen are paticularly sensitive to Ca. Addition of very small amount of boron to cultural media was apparently synergistic to the action of sucrose and Ca in pollen germination and tube elongation. This action was extended to a higher level of boron concentraton. Combined application of boron, Ca and sucrose always gave the better results in pollen growth and protection against pollen bursting much more than when used singly. This indicated that there is a direct relationship between better growth of pollen and increased rigidity of pollen cell wall. A higher level of Ca concentration tended to increase bursting rate of pollen grains and decrease that of pollen tubes, while boron always depressed the rate of bursting. This was considered due to increased failure in pollen germination at high level of Ca that favors pollen tube elongation. The fact that Ca show an antagonistic effect on the suppressive action of high level of boron in pollen growth and shows different effect in response to pollen bursting from boron, suggested mode of Ca and boron action in the presence of sucrose is quiate different, although to increase in rigidity of pollen cell wall by them is in common nature. It was postulated therefore that Ca acts on pectins of pollen cell wall largely as "non-metabolic" and boron as "metabolic" promoter is pollen growth and protecting pollen bursting, since boron and Ca have common nature in strengthening the pollen cell wall but act differently.but act differently.

• Applied Microscopy
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• 제35권4호
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• pp.74-83
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• 2005

인삼의 소포자 발달에 따라 화분벽의 형성과정을 밝히고자 소포자 4분자 시기부터 화분이 성숙되기까지의 전 과정을 투과 및 주사 전자현미경으로 관찰하였다. 화분벽의 발달은 감수분열이 끝나고 소포자 4분자가 callose에 둘러싸여 있을 때 시작된다. 화분벽 발달 초기에는 원형질막이 두터워지고 구불구불해지며 원형질막 바깥쪽에 섬유성 구조물이 나타나기 시작하고 이 섬유성 구조물은 점점 뚜렷하게 나타나고 premexine으로 발달한다. 원형질막의 함입으로 형성된 돌출부와 premexine이 연결되어 단간이 발달하고 성숙화분에서는 endexine에 일시적으로 흰색의 선이 관찰되었다. 표벽발달이 완료되면 hypertrophic Golgi에서 형성되는골지소낭에 의하여 내벽이 발달하고 발아구 부위에서는 내벽이 비후되어 나타났다. 성숙한 인삼화분은 3구형 화분으로서 약 $20{\mu}m$ 크기이며 표벽무늬는 세망상형을 나타내었다.

• 식물조직배양학회지
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• 제21권5호
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• pp.253-275
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• 1994

Many flowering plants possess genetically controlled self -incompatibility (SI) system that prevents inbreeding and promotes outcrosses. SI is usually controlled by a single, multiallelic S-locus. In gametophytically controlled system, SI results when the S-allele of the pollen is matched by one of the two S-alleles in the style, while in the sporophytic system self-incompatible reaction occurs by the interaction between the pistil genotype and genotype of, not the pollen, but the pollen parent In the former system the self-incompatible phenotype of pollen is determined by the haploid genome of the pollen itself but in the latter the pollen phenotype is governed by the genotype of the pollen parent along with the occurrence of either to-dominant or dominant/recessive allelic interactions. In the sporophytic type the inhibition reaction occurs within minutes following pollen-stigma contact, the incompatible pollen grains usually failing to germinate, whereas in gametophytic system pollen tube inhibition takes place during growth in the transmitting tissue of the style. Recognition and rejection of self pollen are the result of interaction between the S-locus protein in the pistil and the pollen protein. In the gametophytic SI the S-associated glycoprotein which is similar to the fungal ribonuclease in structure and function are localized at the intercellular matrix in the transmitting tissue of the style, with the highest concentration in the collar of the stigma, while in the sporophytic SI deposit of abundant S-locus specific glycoprotein (SLSG).is detected in the cell wall of stigmatic papillae of the open flowers. In the gametophytic system S-gene is expressed mostly at the stigmatic collar the upper third of the style length and in the pollen after meiosis. On the other hand, in the sporophytic SI S-glycoprotein gene is expressed in the papillar cells of the stigma as well as in e sporophytic tape is cells of anther wall. Recognition and rejection of self pollen in the gametophytic type is the reaction between the ribonuclease in the transmitting tissue of the style and the protein in the cytoplasm of pollen tube, whereas in the sporophytic system the inhibition of selfed pollen is caused by the interaction between the Sycoprotein in the wall of stigmatic papillar cell and the tapetum-origin protein deposited on the outer wall of the pollen grain. The claim that the S-allele-associated proteins are involved in recognition and rejection of self pollen has been made merely based on indirect evidence. Recently it has been verified that inhibition of synthesis of S$_3$ protein in Petunia inflata plants of S$_2$S$_3$ genotype by the antisense S$_3$ gene resulted in failure of the transgenic plant to reject S$_3$ pollen and that expression of the transgenic encoding S$_3$ protein in the S$_1$S$_2$ genotype confers on the transgenic plant the ability to reject S$_3$ pollen. These finding Provide direct evidence that S-proteins control the s elf-incompatibility behavior of the pistil.

• Journal of Plant Biology
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• 제5권2호
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• pp.1-5
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• 1962

Attempts were made in order to make clear the meiotic irregularities, male gametophyte formation and spermatogenesis for the purpose of applying these embryological facts to taxonomic works. Followings are the results obtained : 1. Meiosis is extremely irregular, giving rise to giant, micro, and empty, pollens. Meiotic division in each PMC is observed synchronizing. 2. In the microspore immediately before the vegetative-generative nuclear division, the nucleus locates appressed to the inner wall, most of the other part of the cell being occupied by large vacuoles. 3. Spindle symmetry in the microspore nuclear division is of intermediate type. 4. Nuclear divisions in each micropore are not synchronized as in meiosis. 5. Generative nucleus is located in close contact with the inner wall, while the vegetative nucleus occupies the central part of pollen grain. The pollen in this stage looks somewhat like broad bean. Afterward the generative nucleus loses contact with the wall, the nuclear shape changing from lenticular to roundsh. 6. The generative nucleus in fully matured pollen grain usually takes the shape of crescence, those in abortive pollen, lenticular or ellipsoidal, etc.

• Journal of Plant Biology
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• 제38권1호
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• pp.25-32
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• 1995

The distribution of RNA in the anther wall of Brassica napus during male gametogenesis was followed by 3H-uridine autoradiography. Silver grain(SG) density was not above background in the anther wall just after microspore was released from tetrad callose wall. Significant accumulation of SGs occurred in tapetum, endothecium, and epidermis before microspore vacuolation. Accumulation of RNA in the tapetal cells was peak before the vaculation occurred in the microspore. With the onset of tapetal senescence at the partially vacuolated microspore stage, SGs decreased and they completely disappeared in the tapetum at the bicelled pollen stage. Accumulation of RNA in the endothecial cells was peak after the microspore mitosis and continued just after the generative cell mitosis. Appreciable SGs also occurred in cells of epidermis from nonvacuolate microspore stage to bicelled pollen stage. During this period, SG density was almost same and was not high as compared with tapetum or endothecium. At tricelled mature pollen stage, no incorporation occurred in anther wall. SGs were found mostly over the nucleouls and chromation of the cell nuclei.

• Journal of Plant Biology
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• 제37권2호
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• pp.203-221
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• 1994

한국산 나자식물 5과 12속 19분류군을 대상으로 광학현미경, 주사전자현미경 및 투과전자현미경을 이용하여 화분의 형태를 비교 관찰하고 기재하였으며, 각 과별 검색표를 작성하였다. 분류학적으로 볼 때 취급된 나자식물의 화분립은 모양, 크기, 표면상태, 표면무늬, 기낭의 유무 및 돌기의 유무에 의해 뚜렷이 구분되어 속간 및 속 이하의 분류군에는 유용하였으나, Pinus속내의 종들은 본 연구에서 관찰된 화분립의 크기나 표면무늬에 의해서는 화분형질의 중복으로 인해 종분류는 유용하지 않은 것으로 밝혀졌다. 소나무과내의 Picea속에 속하는 P. koraiensis의 화분립은 기낭의 형태가 불규칙하고, 몸체에 비해 기낭의 크기가 크며, 표벽이 얇기 때문에 기낭을 갖는 Pinus속과 Abies속의 분류군과는 차이점이 뚜렷하다. 또한 Abies속의 특징으로 기재된 모부의 중앙부위에서 기낭쪽으로 갈수록 표벽이 얇아진다는 점, 화분림 몸체의 표면이 비교적 굴곡이 심하지 않다는 점과 화분립의 크기가 크다는 점으로 볼 때 P. koraiensis는 기낭을 갖는 Pinus속과 Abies속 중 Abies속과 화분학적으로 유연관계가 가까운 것으로 추정된다. 투과전자현미경관찰을 통해 기낭을 갖는 화분립을 조사한 결과 근극에는 내표벽과 외표벽이 모두 존재하나, 서로 분리되어 외표벽은 기낭과 연결되고 내표벽은 원극을 이룬다. 또한 구과목의 분류군들에 있어 소나무과를 제외한 주목과, 난우송과 및 측백나무와 일부 분류군의 내표벽이 여러 층으로 구성된 관상구조로 나타났다. 주사전자현미경으로 기낭을 관찰한 결과 표면무늬는 유공상이고 미세한 pit가 존재하는 것으로 관찰되었다. 기낭의 표면무늬는 광학현미경상에서 망상으로 보이나 투과전자현미경으로 관찰해 본 결과 이는 기낭내부의 망상구조가 광학현미경하에서 투시된 것으로 밝혀졌다.

• Journal of Plant Biology
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• 제10권3_4호
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• pp.1-3
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• 1967

Observations were made on Crinum and Catharanthus pollen growth in artificial media by an ultraviolet transmission fluorescence microscope showing synergistic effect on pollen growth with calcium (Ca) and aureomycin. Bright yellow fluorescence of aureomycin enabling to trace out at tissue or cellular level did reveal that the greater accumulation of fluorescence occurred in the pollen tube wall if Ca was supplemented to the media than when aureomycin alone was present. The promotive pollen growth the media of Ca alone was further enhanced by the addtion of aureomycin. It was assumed that the promoted pollen growth with aureomycin in the Ca media was probably brought about by a supporting role of aureomycin in the Ca action.

• Journal of Plant Biology
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• 제8권1_2호
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• pp.19-23
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• 1965

Interaction occuring among the different Ca concentrations, pH and temperatures in the promotive effect of Ca in pollen growth was studied by using pollen from Crinum asiaticum and Cryptostegia grandiflora. Data for pollen tube elongation were found to be more indicative of representing the promotive action of Ca ion in pollen growth than those for pollen germination, and were served to evaluate the experimental results. The pollen growth increased as the concentration of Ca increase. The optimal pH range for pollen growth shifted from the lower pH to the higher as the concentration of Ca increase. The characteristic Ca effect was disappeared, and no pH effect at various ranges was observed when pollen grains were grown at the low temperature(8$^{\circ}C$). The Ca effect became quite pronounced if temperature were raised. The Ca effect became even mroe striking if the condition was in higher pH ranges (weak alkaline). Higher pH ranges were found to be more favorable for the Ca action, whereas higher temperature was required to bring about more pronounced Ca effect. Thus, the longest pollen tube was obtained with the highest pH, temperature adopted for the medium supplemented with Ca in the present experiment, and the shortest tube with the lowest temperature applied at the highest pH. Pectin synthesis in pollen tube was considered as a metabolic process, whereas Ca binding in pectin of the pollen tube wall as non-metabolic in nature. Disappearance of Ca effect at the low temperature was probably brought about by blocking the metabolic synthesis of pectin, and nonmetabolic Ca binding seems to take place more extensively with higher concentrations of Ca and at higher pH levels than the lower.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1996년도 제10회 식물생명공학심포지움 고등식물 발생생물학의 최근 진보
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• pp.48-60
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• 1996

We previously identified and characterized a predominantly pollen-expressed gene of Petunia inflata that encodes a receptor-like kinase named PRK1. The extracellular domain of PRK1 contains leucine-rich repeats which have been implicated in protein-protein interactions, and the cytoplasmic domain was found to autophosphorylate on serine and tyrosine. To investigate the function PRK1 in pollen development, we transformed P. inflata plants with a construct containing the promoter of a predominantly pollen-expressed gene of tomato, LAT52, fused to an antisense PRK1 cDNA corresponding to part of the extracellular domain of PRK1, There transgenic plants were found to each produce approximately equal amounts of normal and aborted pollen. Analysis of the inheritance of the transgene inserts in two of the transgenic plants, ASRK-13 and ASRK-20, to their progeny revealed that certain transgene inserts cosegregated with the pollen abortion phenotype. Microscopic examination of the aborted pollen grains showed that their outer wall, the exine, was essentially normal, but that their cytoplasm contained only starch-like granules. Staining of the nuclei of the microspores at different stages of uninucleate stage. However, at subsequent stages half of the microspores completed mitosis and developed into normal binucleate pollen, but the other half initially remained uninucleate, then lost their nucleio. Analysis of the amounts of PRK1 mRNA and the antisense PRK1 transcript suggested that the pollen abortion phenotype most likely resulted from down-regulation of the PRK1 gene by the antisense PRK1 transgene. These results suggest that PRK1 plays an essential role in a signal transduction pathway that mediates post-meiotic development of microspores.

• 한국자원식물학회지
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• 제28권2호
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• pp.235-242
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• 2015

국내 도입된 하이부쉬 블루베리의 품종 선발의 기초 자료로 활용하기 위하여 블루베리의 형태적 및 품종별 화기 특성에 관해 연구하였다. 블루베리의 수술의 형태를 보면 화사는 판형이었고 모용이 잘 발달되어 있으며, 개약 시 약벽이 열개되지 않고 돌출된 두 개의 관으로 꽃가루가 배출되어 독특하였다. 화분은 3월 하순경에 감수 분열된 후에 분리되지 않은 채로 성숙한 사분자 화분(tetrad pollen)이었다. 약당 사분자 화분립 수는 400~1,300개였으며, 화분립 수가 많은 품종이 발아율도 높은 편이었다. 블루베리의 암술은 5개의 심피로 구성되어 있으며, 화주는 갈라진 부분이 없이 하나였다. 자방당 배주 수는 39~67개 정도였으며, 각 품종별로 변이 계수가 11.6~31.0%로 큰 편이었다. ‘Bluejay’와 ‘Sharpblue’간의 자가 및 타가교배 결과 자가교배보다 타가교배에서 종자 형성률이 높았다.