• Plant Breeding and Biotechnology
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• 제6권4호
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• pp.381-390
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• 2018

Percentage of aerenchyma area has been closely linked with amounts of methane emitted by rice. A diversity panel of 39 global rice varieties were examined to determine genetic variation for root transverse section (RTS), aerenchyma area, and % aerenchyma. RTS and aerenchyma area showed a strong positive correlation while there existed no significant correlation between RTS area and % aerenchyma. Five varieties previously shown to differ in methane emissions under field conditions were found to encompass the variation found in the diversity panel for RTS and aerenchyma area. These five varieties were evaluated in a greenhouse study to determine the relationship of RTS, aerenchyma area, and % aerenchyma with methane emissions. Methane emissions at physiological maturity were the highest for 'Rondo', followed by 'Jupiter', while 'Sabine', 'Francis' and 'CLXL745' emitted the least. The same varietal rank, 'Rondo' being the largest and 'CLXL745' the smallest, was observed with RTS and aerenchyma areas. RTS and aerenchyma area were significantly correlated with methane emissions, r = 0.61 and r = 0.57, respectively (P < 0.001); however, there was no relationship with % aerenchyma. Our results demonstrated that varieties with a larger root area also developed a larger aerenchyma area, which serves as a gas conduit, and as a result, methane emissions were increased. This study suggests that root transverse section area could be used as a means of selecting germplasm with reduced $CH_4$ emissions.

• 한국작물학회지
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• 제43권2호
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• pp.77-82
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• 1998

Aerenchyma development in rice (Oryza sativa L.) roots is quite important for adaptation to waterlogged or reduced soil conditions. Anatomical observations were carried out to clarify the development of schizogenous and lysigenous aerenchyma in elongating crown roots of rice. The crown roots of 3rd and 4th phytomer were taken from rice plants of the 8th leaf stage grown by hydroponic culture. The schizogenous intercellular spaces in the cortex of crown root tip were observed using a light microscope with semi ultra-thin sections and the lysigenous aerenchyma in mature tissue of crown root were observed using a cryo scanning electron microscope (cryo-SEM) with freezing fracture method. The schizogenous intercellular spaces in the root tip exist obviously in the middle portion of cortical cell layers close to the root-root cap junction, but not in root cap, stele and outer cell layers of cortex. The air spaces were formed at the junction of four neighbouring cells of inner cortex in the transverse sections, and between longitudinal cell layer connected along the root axis. Although many of those spaces were filled with liquid, some spaces seem to exist as air spaces. The lysigenous aerenchyma in the cortex, which hardly filled with liquid, emerged at 3-4 cm segment from the root tip and increased toward the basal region of root axis. The developing process of lysigenous aerenchyma was primarily separation of a radial row of cells caused by the shrinking and collapsing of cortical cells and then formation of septa along the radial cell rows by the fusion of cell wall with each other. These results suggest that the schizogenous and lysigenous aerenchyma playa role as a passage for the movement of oxygen into the root tip region where oxygen is required for respiration.

• 생명과학회지
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• 제25권1호
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• pp.37-43
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• 2015

옥수수(Zea mays) 원뿌리에서 에틸렌 전구체인 1-aminocyclopropane-1-carboxylic acid (ACC), indole-3-acetic acid (IAA) 그리고 methyl jasmonate (MeJA)가 통기조직의 발달에 미치는 영향을 조사하였다. 식물호르몬 처리는 원뿌리의 종단 구성에 영향을 미치므로 control과 호르몬 처리된 뿌리의 비교 가능한 위치를 정할 필요가 있었다. 이를 위하여 원뿌리의 정단을 PR0, 기부를 PR100이라 정의하고 이 두 지점 사이를 길이에 비례하여 PR25, PR50, PR75로 구분하였다. 대조군 뿌리의 PR25와 PR50 부분에서는 통기조직이 관찰되지 않았으며 PR75 부분에서는 드물게 통기조직이 나타나기도 하였다. PR75 부위의 통기조직 면적은 ACC 또는 IAA가 존재할 때 증가하였다. 반면, MeJA는 옥수수 원뿌리가 침수되지 않았을 때와 침수되었을 때 서로 다른 차등 효과를 나타내었다. 뿌리가 침수되지 않았을 때 MeJA는 통기조직의 발달을 억제하였다. 반면, 뿌리를 침수 시키면 통기조직의 면적이 증가하는데 그 면적은 MeJA에 의하여 더욱 증가되었다. 한편, 곁뿌리 원기는 그 주변 피층세포의 통기조직 발달에 수반되는 세포사멸을 억제하는 것으로 알려져 있었다. 곁뿌리 원기에 의해 억제되는 통기조직의 발달은 위에 기술한 바와 같이 통기조직의 발달을 촉진하는 세 가지 호르몬들에 의해서도 회복되지 않았다. 이는 발달하는 곁뿌리 원기가 억제하는 통기조직 발달 조절의 세부 단계는 식물호르몬들이 작용한 이후 단계일 가능성을 보여주는 것이다.

• Journal of Plant Biology
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• 제26권1호
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• pp.41-51
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• 1983

This study was carried out to investigate ontogeny of stomata and aerenchyma tissue in Trapa natans L. var. bispinosa Makino, an aquatic plant. Ontogeny of stomata in this plant was an aperigenous type surrounding with 5 to 8 epidermal cells without subsidiary cells. Stomata were distributed abundantly on the upper surface of leaf, however, no stoma was found on the lower surface of leaf, and on the epidermis of reproductive organ, petiole and stem. Ontogency of aerenchyma tissue was progressed with five steps; 1) formation of angular cells by division of cortex cells, 2) development of small and large globular cells in accompany with schizogenous intercellular space, 3) enlargement of globular cells and more expansion of intercellular space, 4) cell induction of long elliptic and triarmed shape, 5) completion of the largest intercellular space from endodermis toepidermis. During the growth period two types of leaf were appeared at each node of stems; one type was a submerged and early-fallen leaf, the other was a floating leaf on water surface.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.328-328
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• 2017

Drought is a major limiting factor that reduces rice production and occurs often especially under recent climate change. Plants have the ability to alter their developmental morphology in response to changing environment, which is known as phenotypic plasticity. In our previous studies, we found that one chromosome segment substitution line (CSSL50 derived from Nipponbare and Kasalath crosses) showed no differences in shoot and root growth as compared with the recurrent genotype, Nipponbare under non-stress condition but showed greater growth responses compared with Nipponbare under mild drought stress condition. We hypothesized that reducing root respiration as metabolic cost, which may be largely a consequence of aerenchyma formation would be one of the key mechanisms for root plasticity expression. This study aimed to evaluate the root respiration and aerenchyma formation under various soil moisture conditions among genotypes with different root plasticity. CSSL50 together with Nipponbare and Kasalath were grown under waterlogged conditions (Control) and mild drought stress conditions (20% of soil moisture content) in a plastic pot ($11cm{\times}14cm$, ${\varphi}{\times}H$) and PVC tube ($3cm{\times}30cm$, ${\varphi}{\times}H$). Root respiration rate was measured with infrared gas analyzer (IRGA, GMP343, Vaisala, Finland) with a closed static chamber system. There was no significant difference between genotypes in control for shoot and root growth as well as root respiration rate. In contrast, all the genotypes increased their root respiration rates in response to mild drought stress. However, CSSL50 showed lower root respiration rate than Nipponbare, which was associated by higher root aerenchyma formation that was estimated based on internal gas space (porosity) under mild drought stress conditions. Furthermore, there were significant negative correlations between root length and root respiration rate. These results imply that reducing the metabolic cost (= root respiration rate) is a key mechanism for root plasticity expression, which CSSL50 showed under mild drought.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 추계학술대회
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• pp.113-113
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• 2017

• 한국작물학회지
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• 제42권6호
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• pp.778-782
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• 1997

율무 뿌리의 수분 적성 및 생육 단계별 한발피해 정도를 구명하기 위해 실시한 시험결과를 요약하면 다음과 같다. 1. 율무 종자의 발아는 산소가 부족한 혐기조건하에서는 극히 부량하였으나 발아이후에는 해를 받지 않는 작물이었다. 2. 율무 뿌리의 횡단면 세포배열은 세포간극이 큰 직열구조로 되어 있었고 담수하에 놓이면 피층(통기구조) 면적이 점차 확대됨을 알 수 있었다. 3. 담수상태하의 율무는 지주근 및 기근이 상위절에서 많이 발생되었을 뿐만 아니라 엽고병 발병이 억제되었고 등숙이 양호하였다. 4. 율무의 생육 단계별 한발피해는 출수기 한발처리에서 가장 피해가 컸다.

• Applied Microscopy
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• 제38권4호
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• pp.307-314
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• 2008

일부 수생식물은 휴면구조로 엽상체가 변형된 잠아를 형성하여 적응 생존한다. 부유부엽성 식물인 개구리밥은 가을에 형성된 잠아로 동절기 물속에 가라앉아 휴면상태로 겨울을 난다. 이들 잠아는 엽상체의 특정 부위에서 기원하나 모엽상체와 달리 통기조직의 발달이 미흡하고 조직의 밀도가 높아 수중 침강에 유리한 구조로 분화된다. 잠아조직 내에는 일반적으로 기온상승 시 생장재개에 바로 이용할 수 있는 영양분이 저장되어 있다. 이러한 특성을 지닌 개구리밥 잠아의 형성 및 발아에 대해서는 생리적, 생화학적으로 다양한 연구가 진행되고 있으나 잠아조직 세포의 미세구조 연구는 미흡한 상태이다. 이 연구에서는 엽상체와 잠아 엽육조직의 분화, 통기조직의 발달, 녹말의 분포, 세포수준에서의 미세구조 발달양상을 비교 연구하였다. 엽육조직이 비교적 분화되어 있는 모엽상체는 통기조직이 잘 발달되어 엽상체 용적의 약 $37{\sim}45%$를 차지하였다. 반면, 잠아는 엽육조직의 분화 없이 조직 내 통기조직의 발달이 미흡하여 전체 용적의 약 $9{\sim}15%$를 차지하였다. 모엽상체 엽육세포와 달리 잠아 세포내 세포질은 매우 치밀하며 엽록체 기질에는 녹말이 다량 축적되어 있다. 엽록체, 세포벽, 액포, 세포막은 모엽상체 세포내 특성과 다른 양상으로 분화하였다. 이와 같이 잠아는 통기조직의 미흡한 발달, 세포질의 높은 밀도, 녹말의 다량 축적 등으로 조직의 밀도를 높게 하여 겨울철 휴면상태에 잘 적응된 구조로 발달시켜 축소된 개구리밥 식물체 생활사에 중요한 역할을 수행하는 독특한 구조로 분화하였다. 매우 빠른 생장으로 수면에 넓게 분포하는 개구리밥은 수생환경에 필요한 양분 및 빛을 차단하여 수생의 생태에 나쁜 영향을 미치기도 한다. 그러나 잠아형성 촉진 조건을 가해 주면 식물체는 쉽게 물속에 가라앉아 휴면상태를 유지할 수 있는 것으로 알려져 있다. 다른 식물 종들은 생장 및 형성 조건을 조절하기 어렵지만 개구리밥 식물체의 잠아는 이러한 구조적 특징으로 형성이 쉽게 조절될 수 있어 수생환경 개선에 유망한 후보가 되고 있다. 향후 본 연구의 모엽상체와 잠아의 생장 및 구조 특성을 이용하여 유사 수생식물 잠아의 생장특성에 적용하면 수생환경정화 등의 영역에서 유용하게 활용될 수 있는 휴면구조가 될 것이다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.142-142
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• 2020

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.281-281
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• 2017

Recently, global warming by greenhouse gas effect is getting danger and danger for human life and agriculture at present. In Indonesia, according to heavy rain in the agriculture land is often covered by excess water in result crop growth would be affected negative. This water stress triggers roots failure in anaerobic condition for upland crop because of limiting roots respiration. Chili pepper grows in upland sometimes in touch with waterlogging due to rainfall and /or over flow water from river in Indonesia. In this case, roots growing is inhibited by effect of shortage of oxygen at root cap. Therefore, the objective of this study is to observe the plant behavior in waterlogging using mahor local genotypes (Ferosa, Laris, Romario) in Sumatra. The experiment was kept by at 1cm depth water above the soil surface as a waterlogged treatment for ---days. As a result, waterlogging affected plant growth of chili negatively, especially for roots growth. Almost roots were getting bad and changed color for brown during waterlogging. A significant negative effect for nutrient absorption by roots was found in dry weight of all varieties during waterlogging. Dry weight of roots was decreased by 81.4% and 67.6%, and those of aerial part decreased by 74% and 67.2% compared with control in Ferosa and Romario at 1week after treatment. On the other hand, dry weight of roots was decreased only 35% in Laris. Therefore, Laris has a tolerance for waterlogging compared to with other varieties. Also, Laris in SPAD value was kept initial level during waterlogging however those of Ferosa and Romario decreased. Finally, due to impact of waterlogging, it may be the roots become failure because of less aerenchyma formation under anaerobic condition. We need confirm aerenchyma formation morphologically in the future.