The effects of ethephon on the constitutive aerenchyma formation in roots were studied with a rice variety Yangdao 6 as material. The number of air spaces formed by disintegrated cells in mediopellis increased signifi...The effects of ethephon on the constitutive aerenchyma formation in roots were studied with a rice variety Yangdao 6 as material. The number of air spaces formed by disintegrated cells in mediopellis increased significantly with the rising ethephon concentrations, whereas superoxide dismutase (SOD) activity showed downward trends. Compared with the control, the expression levels of xyloglucan endotransglycosylase (XET) gene were markedly higher both at the apical 10 mm and distal parts of roots in 100 mg/L ethephon treated plants. The accumulation of XET was supposed to be associated with the aerenchyma development. Furthermore, earlier cortical cell death was observed under the ethephon treatments, and most of nuclei of cells at 4 mm from the root apex disintegrated with many Golgi apparatus, mitochondria and membrane-bound vesicles around the cell wall.展开更多
Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global warming.Flooded soils play a significant role in methaneproduction,where the anaerobic cond...Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global warming.Flooded soils play a significant role in methaneproduction,where the anaerobic conditions promote the production of methane by methanogenicmicroorganisms.Rice fields contribute a considerable portion of agricultural methane emissions,as riceplants provide both factors that enhance and limit methane production.Rice plants harbor both methaneproducingand methane-oxidizing microorganisms.Exudates from rice roots provide source for methaneproduction,while oxygen delivered from the root aerenchyma enhances methane oxidation.Studies haveshown that the diversity of these microorganisms depends on rice cultivars with some genes characterizedas harboring specific groups of microorganisms related to methane emissions.However,there is still aneed for research to determine the balance between methane production and oxidation,as rice plantspossess the ability to regulate net methane production.Various agronomical practices,such as fertilizerand water management,have been employed to mitigate methane emissions.Nevertheless,studiescorrelating agronomic and chemical management of methane with productivity are limited.Moreover,evidences for breeding low-methane-emitting rice varieties are scattered largely due to the absence ofcoordinated breeding programs.Research has indicated that phenotypic characteristics,such as rootbiomass,shoot architecture,and aerenchyma,are highly correlated with methane emissions.This reviewdiscusses available studies that involve the correlation between plant characteristics and methaneemissions.It emphasizes the necessity and importance of breeding low-methane-emitting rice varieties inaddition to existing agronomic,biological,and chemical practices.The review also delves into the idealphenotypic and physiological characteristics of low-methane-emitting rice and potential breeding techniques,drawing from studies conducted with diverse varieties,mutants,and transgenic plants.展开更多
根水力的电导率被显示了在磷(P) 缺乏下面减少。这研究调查通气组织的形成与这个变化有关的独桅三角帆船。Rootanatomy，以及根水力的电导率在玉米(Zea mays L.) 被学习在不同的磷营养条件下面的根。在应力显示出的 P 下面的植物根提高...根水力的电导率被显示了在磷(P) 缺乏下面减少。这研究调查通气组织的形成与这个变化有关的独桅三角帆船。Rootanatomy，以及根水力的电导率在玉米(Zea mays L.) 被学习在不同的磷营养条件下面的根。在应力显示出的 P 下面的植物根提高了外皮的房间的降级，通气组织形成与他们的减少的根被联系水力的电导率，支持我们让在根柱体在强调 ofphosphorus 的根阻碍的外皮形成水的光线的运输的空格通风的假设。进一步的证据由于 genotyplc 差别来自变化 inaerenchyma 形成。有在他们的根外皮的不同的孔的五个玉米近交系与他们的根显示出一道重要负相关水力的电导率。当如此的处理足够被延长时，相对含水量也被发现的射击在 P 足够的比那在 P 缺乏的玉米植物降低，建议由于 P-deficlent 的水力的电导率种的降低的根的水运输的限制。展开更多
Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of s...Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of six locations spanning from 400 to 1,400 m.The population colonizing the highest elevation modifications in different plant organs.Roots showed increased metaxylem number and area.In the stem,especially outside of the vascular tissue,there was intensive sclerification indicative of increased xeromorphy as a survival strategy.At the highest elevation,leaves were wider;aerenchyma formation and increased sclerification were noted in the leaf sheath;and a greater proportion of storage parenchyma was observed in the leaf blade,all indicators of succulence.In contrast,leaves at lower elevations had xeric morphological features such as increased epidermal thickness,sclerification and more developed metaxylem area.In conclusion,shifting of morphological features in below-and above-ground plant parts of C.serrulatus were linked to shifts in environmental factors along this elevation gradient,thus enabling the successful distribution of this species along this elevation gradient.展开更多
野古草(Arundinella anomala var. depauperata Keng)在三峡库区长江及其支流江(河)岸有广泛分布,对水淹有很好的耐受能力。有研究表明许多植物在水淹时通气组织发生增强,通气组织的产生改善了植株通气状况,提高了植物对水淹的抵御能力...野古草(Arundinella anomala var. depauperata Keng)在三峡库区长江及其支流江(河)岸有广泛分布,对水淹有很好的耐受能力。有研究表明许多植物在水淹时通气组织发生增强,通气组织的产生改善了植株通气状况,提高了植物对水淹的抵御能力。为了研究水淹是否会影响野古草的通气组织发生以及野古草通气组织发生对水淹的反应,考察了不同水淹深度、不同水淹时间和不同水淹方式处理时野古草茎中通气组织的发生情况。实验中共设置3个水淹深度:不进行水淹(对照)、植株地下部分淹没、植株完全淹没于水下2m深处;5个淹没时间:植株被淹没的时间长度分别为5、10、20、30d和60d;2种水淹方式:连续水淹和间歇水淹。实验结果表明:(1)在无水淹情况下野古草茎中可以产生通气组织,通气组织产生随植株的生长而增强;水淹加快了野古草通气组织发生的进程,促进了野古草通气组织的提前发生。(2)野古草茎中通气组织并不会因为水淹的时间越长而产生越多,植株通气组织的大小达到一定程度后不再因水淹时间的增长而继续增大。(3)淹没深度对通气组织发生有一定影响,总的看来,地下部分淹没野古草植株的通气组织发生要强于完全淹没植株。(4)不同水淹方式对野古草通气组织发生的影响因水淹深度不同而有差异。在完全淹没情况下,连续水淹植株的通气组织比间歇水淹植株的通气组织发达;在地下部分淹没情况下,除水淹初期外,随水淹时间的延长,连续水淹植株通气组织发生与间歇水淹植株没有差异。展开更多
基金supported by the National Natural Science Foundation of China (Grant No.30871467)
文摘The effects of ethephon on the constitutive aerenchyma formation in roots were studied with a rice variety Yangdao 6 as material. The number of air spaces formed by disintegrated cells in mediopellis increased significantly with the rising ethephon concentrations, whereas superoxide dismutase (SOD) activity showed downward trends. Compared with the control, the expression levels of xyloglucan endotransglycosylase (XET) gene were markedly higher both at the apical 10 mm and distal parts of roots in 100 mg/L ethephon treated plants. The accumulation of XET was supposed to be associated with the aerenchyma development. Furthermore, earlier cortical cell death was observed under the ethephon treatments, and most of nuclei of cells at 4 mm from the root apex disintegrated with many Golgi apparatus, mitochondria and membrane-bound vesicles around the cell wall.
基金supported by the Improvement of Green Rice Plant Type Using Genetic Information Program, Rural Development Administration, Korea (Grant No. PJ01699202)
文摘Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global warming.Flooded soils play a significant role in methaneproduction,where the anaerobic conditions promote the production of methane by methanogenicmicroorganisms.Rice fields contribute a considerable portion of agricultural methane emissions,as riceplants provide both factors that enhance and limit methane production.Rice plants harbor both methaneproducingand methane-oxidizing microorganisms.Exudates from rice roots provide source for methaneproduction,while oxygen delivered from the root aerenchyma enhances methane oxidation.Studies haveshown that the diversity of these microorganisms depends on rice cultivars with some genes characterizedas harboring specific groups of microorganisms related to methane emissions.However,there is still aneed for research to determine the balance between methane production and oxidation,as rice plantspossess the ability to regulate net methane production.Various agronomical practices,such as fertilizerand water management,have been employed to mitigate methane emissions.Nevertheless,studiescorrelating agronomic and chemical management of methane with productivity are limited.Moreover,evidences for breeding low-methane-emitting rice varieties are scattered largely due to the absence ofcoordinated breeding programs.Research has indicated that phenotypic characteristics,such as rootbiomass,shoot architecture,and aerenchyma,are highly correlated with methane emissions.This reviewdiscusses available studies that involve the correlation between plant characteristics and methaneemissions.It emphasizes the necessity and importance of breeding low-methane-emitting rice varieties inaddition to existing agronomic,biological,and chemical practices.The review also delves into the idealphenotypic and physiological characteristics of low-methane-emitting rice and potential breeding techniques,drawing from studies conducted with diverse varieties,mutants,and transgenic plants.
基金Supported by the National Natural Science Foundation of China （30660086）.
文摘根水力的电导率被显示了在磷(P) 缺乏下面减少。这研究调查通气组织的形成与这个变化有关的独桅三角帆船。Rootanatomy，以及根水力的电导率在玉米(Zea mays L.) 被学习在不同的磷营养条件下面的根。在应力显示出的 P 下面的植物根提高了外皮的房间的降级，通气组织形成与他们的减少的根被联系水力的电导率，支持我们让在根柱体在强调 ofphosphorus 的根阻碍的外皮形成水的光线的运输的空格通风的假设。进一步的证据由于 genotyplc 差别来自变化 inaerenchyma 形成。有在他们的根外皮的不同的孔的五个玉米近交系与他们的根显示出一道重要负相关水力的电导率。当如此的处理足够被延长时，相对含水量也被发现的射击在 P 足够的比那在 P 缺乏的玉米植物降低，建议由于 P-deficlent 的水力的电导率种的降低的根的水运输的限制。
文摘Chrysopogon serrulatus(false beard-grass)is a dominant component of vegetation in the foothills of the Himalayas.To study whole plant morphology,individuals of C.serrulatus were collected from three plots at each of six locations spanning from 400 to 1,400 m.The population colonizing the highest elevation modifications in different plant organs.Roots showed increased metaxylem number and area.In the stem,especially outside of the vascular tissue,there was intensive sclerification indicative of increased xeromorphy as a survival strategy.At the highest elevation,leaves were wider;aerenchyma formation and increased sclerification were noted in the leaf sheath;and a greater proportion of storage parenchyma was observed in the leaf blade,all indicators of succulence.In contrast,leaves at lower elevations had xeric morphological features such as increased epidermal thickness,sclerification and more developed metaxylem area.In conclusion,shifting of morphological features in below-and above-ground plant parts of C.serrulatus were linked to shifts in environmental factors along this elevation gradient,thus enabling the successful distribution of this species along this elevation gradient.
文摘野古草(Arundinella anomala var. depauperata Keng)在三峡库区长江及其支流江(河)岸有广泛分布,对水淹有很好的耐受能力。有研究表明许多植物在水淹时通气组织发生增强,通气组织的产生改善了植株通气状况,提高了植物对水淹的抵御能力。为了研究水淹是否会影响野古草的通气组织发生以及野古草通气组织发生对水淹的反应,考察了不同水淹深度、不同水淹时间和不同水淹方式处理时野古草茎中通气组织的发生情况。实验中共设置3个水淹深度:不进行水淹(对照)、植株地下部分淹没、植株完全淹没于水下2m深处;5个淹没时间:植株被淹没的时间长度分别为5、10、20、30d和60d;2种水淹方式:连续水淹和间歇水淹。实验结果表明:(1)在无水淹情况下野古草茎中可以产生通气组织,通气组织产生随植株的生长而增强;水淹加快了野古草通气组织发生的进程,促进了野古草通气组织的提前发生。(2)野古草茎中通气组织并不会因为水淹的时间越长而产生越多,植株通气组织的大小达到一定程度后不再因水淹时间的增长而继续增大。(3)淹没深度对通气组织发生有一定影响,总的看来,地下部分淹没野古草植株的通气组织发生要强于完全淹没植株。(4)不同水淹方式对野古草通气组织发生的影响因水淹深度不同而有差异。在完全淹没情况下,连续水淹植株的通气组织比间歇水淹植株的通气组织发达;在地下部分淹没情况下,除水淹初期外,随水淹时间的延长,连续水淹植株通气组织发生与间歇水淹植株没有差异。
