Competition of sorghum cultivars and densities with Japanese millet (Echinochloa esculenta)

Wu, Hanwen,Walker, Steven R.,Osten, Vikki A.,Robinson, Geoff The Korean Society of Weed Science and The Turfgra 2010 Weed Biology and Management Vol.10 No.3

Field studies were conducted at two locations in southern Queensland, Australia during the 2003-2004 and 2004-2005 growing seasons to determine the differential competitiveness of sorghum (Sorghum bicolor L. Moench) cultivars and crop densities against weeds and the sorghum yield loss due to weeds. Weed competition was investigated by growing sorghum in the presence or absence of a model grass weed, Japanese millet (Echinochloa esculenta). The correlation analyses showed that the early growth traits (height, shoot biomass, and daily growth rate of the shoot biomass) of sorghum adversely affected the height, biomass, and seed production of millet, as measured at maturity. "MR Goldrush" and "Bonus MR" were the most competitive cultivars, resulting in reduced weed biomass, weed density, and weed seed production. The density of sorghum also had a significant effect on the crop's ability to compete with millet. When compared to the density of 4.5 plants per $m^2$, sorghum that was planted at 7.5 plants per $m^2$ suppressed the density, biomass, and seed production of millet by 22%, 27% and 38%, respectively. Millet caused a significant yield loss in comparison with the weed-free plots. The combined weed-suppressive effects of the competitive cultivars, such as MR Goldrush, and high crop densities minimized the yield losses from the weeds. These results indicate that sorghum competition against grass weeds can be improved by choosing competitive cultivars and by using a high crop density of >7.5 plants per $m^2$. These non-chemical options should be included in an integrated weed management program for better weed management, particularly where the control options are limited by the evolution of herbicide resistance.

부산 지하철 휴게 공간 리디자인에 대한 연구 - 대연역 생태 공간 개발 중심으로 -

장무 ( Zhang Wu ),김철수 ( Kim Chulsoo ),조수문 ( Zhao Shuwen ),양혜민 ( Yang Huimin ),장한문 ( Zhang Hanwen ) 한국공간디자인학회 2020 한국공간디자인학회논문집 Vol.15 No.8

(Background and Purpose) This study aimed to redesign the rest space of Busan Daeyeon subway station as the basic data for future design. It attempted to make this research applicable to other subway stations in Busan, guide Busan to build a more comfortable city, promote its development, and improve the convenience and quality of life of city dwellers. To improve the underground space requires putting forward reasonable suggestions for the development of space without damaging the ground environment. These renovations are beneficial to improve the use of underground by citizens and the value of urban underground space development. The purpose of this research is to maximize the preservation of space and facilities in public places. (Method) We emphasized the continuity and accessibility of the space for rest and focused on the elements of regional economy, lifestyle, and ecological technology in urban design. In this research, we hoped to redesign the underground rest area through technology integration, such as natural lighting system, vertical greening of walls, and negative ion ventilation system. The basic direction of underground space design was divided into (1) the healing function; (2) Green energy control function; and (3) practical function. To seek solutions to urban environmental problems and the shortage of urban public space. (Result) According to the configuration of urban space and the composition of facilities, the possibility of improvement and development of urban underground leisure space will be studied based on the survey data of the functional needs and improvement points of the respondents. At present, most of the people living near Daeyeon station are students, and the population density is relatively high. However, due to the convenient transportation, it has become the preferred residence for international students and Korean students of Pukyong National University, Kyungsung University, and Tongmyong University. However, compared to the population density, the rest space is insufficient. To solve these problems, this research used three-dimensional urban space planning. (Conclusion) Through the redesign (redevelopment) of the underground rest area of Daeyeon subway station, this research can be used as the basic data for future design, and it can be applied to other subway stations in Busan, which will enhance the urban construction of the whole Busan and promote its development. Furthermore, it improves the convenience of urban residents and improves the quality of life. Therefore, we should emphasize the continuity and accessibility of public space, and pay attention to the design elements of urban space, regional boundaries, lifestyle, ecological technology, and other urban design elements.

The miR-98-3p/JAG1/Notch1 axis mediates the multigenerational inheritance of osteopenia caused by maternal dexamethasone exposure in female rat offspring

Han Hui,Xiao Hao,Wu Zhixin,Liu Liang,Chen Ming,Gu Hanwen,Wang Hui,Chen Liaobin 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

As a synthetic glucocorticoid, dexamethasone is widely used to treat potential premature delivery and related diseases. Our previous studies have shown that prenatal dexamethasone exposure (PDE) can cause bone dysplasia and susceptibility to osteoporosis in female rat offspring. However, whether the effect of PDE on bone development can be extended to the third generation (F3 generation) and its multigenerational mechanism of inheritance have not been reported. In this study, we found that PDE delayed fetal bone development and reduced adult bone mass in female rat offspring of the F1 generation, and this effect of low bone mass caused by PDE even continued to the F2 and F3 generations. Furthermore, we found that PDE increases the expression of miR-98-3p but decreases JAG1/Notch1 signaling in the bone tissue of female fetal rats. Moreover, the expression changes of miR-98-3p/JAG1/Notch1 caused by PDE continued from the F1 to F3 adult offspring. Furthermore, the expression levels of miR-98-3p in oocytes of the F1 and F2 generations were increased. We also confirmed that dexamethasone upregulates the expression of miR-98-3p in vitro and shows targeted inhibition of JAG1/Notch1 signaling, leading to poor osteogenic differentiation of bone marrow mesenchymal stem cells. In conclusion, maternal dexamethasone exposure caused low bone mass in female rat offspring with a multigenerational inheritance effect, the mechanism of which is related to the inhibition of JAG1/Notch1 signaling caused by the continuous upregulation of miR-98-3p expression in bone tissues transmitted by F2 and F3 oocytes.

Changes in Cell Ca<SUP>2+</SUP> Distribution in Loquat Leaves and Its Effects on Cold Tolerance

Guohua Zheng,Dongming Pan,Xianqian Niu,Hanwen Wu,Jinbiao Zhang 한국원예학회 2014 원예과학기술지 Vol.32 No.5

Calcium has been associated with improved cold tolerance in many crops. The aim of this study was to investigate the changes in leaf cell Ca<SUP>2+</SUP> distribution and cell organelle ultrastructure of loquat (Eriobotrya japonica Lindl.) plants in response to cold stress at -3℃, using transmission electron microscopy (TEM). Two loquat accessions, Zaozhong 6 (a commercial cultivar) and oakleaf loquat (a wild relative) were used. Cold tolerance, as measured by leaf browning rate, was higher in oakleaf plants, and calcium treatment improved cold tolerance in both species. Cold stress first induced inward transport of Ca<SUP>2+</SUP> from the intracellular space. Then, the imported Ca<SUP>2+</SUP> was aggregated around the chloroplast membrane, finally entering the chloroplast. This pattern of Ca<SUP>2+</SUP> distribution in leaf cells occurred earlier in Zaozhong 6 than in the wild loquat. With increasing time of cold exposure, the chloroplast membranes of Zaozhong 6 leaves were damaged, blurred and even disappeared, while those of wild oakleaf loquat leaves maintained their structure longer. In Zaozhong 6, cold stress induced a clear cavity between poorly structured granal thylakoids and vesicles appearing inside the chloroplast, while in oakleaf leaves cold stress had little effect on the ultrastructure of chloroplasts (although chloroplast membranes looked blurred). Loquat leaves accumulated free calcium ions around chloroplasts in response to cold stress, with earlier calcium accumulation occurring in the cold-sensitive cultivar Zaozhong 6 than in wild oakleaf loquat. These results demonstrate that these two loquat species have differences in both cold tolerance and calcium accumulation dynamics.

Differential Frost Tolerance and Enzymatic Activities in the Leaves and Immature Fruits of Loquat (Eriobotrya japonica Lindl.)

Zheng, Guohua,Niu, Xianqian,Zhang, Jinbiao,Wu, Hanwen,Lin, Xiuxiang,Pan, Dongming Korean Society of Horticultural Science 2015 원예과학기술지 Vol.33 No.3

In this experiment, five commercial cultivars and one wild species of loquat were used to investigate frost tolerance and enzymatic activities in leaves and young fruits under cold stress at $-3^{\circ}C$. The frost injury, malondialdehyde (MDA) content, and oxygen-scavenging enzyme activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were studied. This results showed that the wild species 'Wild Oak-leaf' loquat was the most frost tolerant among accessions tested, followed by the cultivar 'Golden Block'. Other cultivars, 'Wu Gong Bai', 'Taicheng 4', 'Xiangzhong 11' and 'Zaozhong 6', were relatively weak in frost tolerance. The enzymatic activities of SOD, POD and CAT increased initially and then decreased as the exposure time increased. However, the enzymatic peak occurred later in the frost-tolerant accession than in the frost-sensitive accession. The correlation coefficients of MDA contents between leaves and immature fruits were from 0.93 to 0.99 in the five commercial loquat cultivars. For the 'Wild Oak-leaf' loquat, the correlation coefficients of MDA and POD were 0.98 and 0.95, respectively, but the coefficients for SOD, CAT and APX were relatively low. In general, there were good correlations between loquat leaves and immature fruits in MDA content and enzyme activities. These results indicate that analysis of these physiological and biochemical activities in loquat leaves could potentially be used to predict the cold tolerance in loquat at immature fruit stage and to accelerate breeding programs for cold tolerance in loquat.

Changes in Cell Ca 2+ Distribution in Loquat Leaves and Its Effects on Cold Tolerance

Guohua Zheng,Dongming Pan,Xianqian Niu,Hanwen Wu,Jinbiao Zhang 한국원예학회 2014 원예과학기술지 Vol.32 No.5

Calcium has been associated with improved cold tolerance in many crops. The aim of this study was to investigatethe changes in leaf cell Ca2+distribution and cell organelle ultrastructure of loquat (Eriobotrya japonica Lindl.) plants in responseto cold stress at -3°C, using transmission electron microscopy (TEM). Two loquat accessions, Zaozhong 6 (a commercial cultivar)and oakleaf loquat (a wild relative) were used. Cold tolerance, as measured by leaf browning rate, was higher in oakleaf plants,and calcium treatment improved cold tolerance in both species. Cold stress first induced inward transport of Ca2+from theintracellular space. Then, the imported Ca2+was aggregated around the chloroplast membrane, finally entering the chloroplast. This pattern of Ca2+distribution in leaf cells occurred earlier in Zaozhong 6 than in the wild loquat. With increasing time ofcold exposure, the chloroplast membranes of Zaozhong 6 leaves were damaged, blurred and even disappeared, while those ofwild oakleaf loquat leaves maintained their structure longer. In Zaozhong 6, cold stress induced a clear cavity between poorlystructured granal thylakoids and vesicles appearing inside the chloroplast, while in oakleaf leaves cold stress had little effecton the ultrastructure of chloroplasts (although chloroplast membranes looked blurred). Loquat leaves accumulated free calciumions around chloroplasts in response to cold stress, with earlier calcium accumulation occurring in the cold-sensitive cultivarZaozhong 6 than in wild oakleaf loquat. These results demonstrate that these two loquat species have differences in both coldtolerance and calcium accumulation dynamics.

Differential Frost Tolerance and Enzymatic Activities in the Leaves and Immature Fruits of Loquat (Eriobotrya japonica Lindl.)

Guohua Zheng,Xianqian Niu,Jinbiao Zhang,Hanwen Wu,Xiuxiang Lin,Dongming Pan 한국원예학회 2015 원예과학기술지 Vol.33 No.3

In this experiment, five commercial cultivars and one wild species of loquat were used to investigate frost tolerance and enzymatic activities in leaves and young fruits under cold stress at -3℃. The frost injury, malondialdehyde (MDA) content, and oxygen-scavenging enzyme activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were studied. This results showed that the wild species ‘Wild Oak-leaf’ loquat was the most frost tolerant among accessions tested, followed by the cultivar ‘Golden Block’. Other cultivars, ‘Wu Gong Bai’, ‘Taicheng 4’, ‘Xiangzhong 11’ and ‘Zaozhong 6’, were relatively weak in frost tolerance. The enzymatic activities of SOD, POD and CAT increased initially and then decreased as the exposure time increased. However, the enzymatic peak occurred later in the frost-tolerant accession than in the frost-sensitive accession. The correlation coefficients of MDA contents between leaves and immature fruits were from 0.93 to 0.99 in the five commercial loquat cultivars. For the ‘Wild Oak-leaf’ loquat, the correlation coefficients of MDA and POD were 0.98 and 0.95, respectively, but the coefficients for SOD, CAT and APX were relatively low. In general, there were good correlations between loquat leaves and immature fruits in MDA content and enzyme activities. These results indicate that analysis of these physiological and biochemical activities in loquat leaves could potentially be used to predict the cold tolerance in loquat at immature fruit stage and to accelerate breeding programs for cold tolerance in loquat.

Changes in Cell Ca²⁺ Distribution in Loquat Leaves and Its Effects on Cold Tolerance

Zheng, Guohua,Pan, Dongming,Niu, Xianqian,Wu, Hanwen,Zhang, Jinbiao Korean Society of Horticultural Science 2014 원예과학기술지 Vol.32 No.5

Calcium has been associated with improved cold tolerance in many crops. The aim of this study was to investigate the changes in leaf cell $Ca^{2+}$ distribution and cell organelle ultrastructure of loquat (Eriobotrya japonica Lindl.) plants in response to cold stress at $-3^{\circ}C$, using transmission electron microscopy (TEM). Two loquat accessions, Zaozhong 6 (a commercial cultivar) and oakleaf loquat (a wild relative) were used. Cold tolerance, as measured by leaf browning rate, was higher in oakleaf plants, and calcium treatment improved cold tolerance in both species. Cold stress first induced inward transport of $Ca^{2+}$ from the intracellular space. Then, the imported $Ca^{2+}$ was aggregated around the chloroplast membrane, finally entering the chloroplast. This pattern of $Ca^{2+}$ distribution in leaf cells occurred earlier in Zaozhong 6 than in the wild loquat. With increasing time of cold exposure, the chloroplast membranes of Zaozhong 6 leaves were damaged, blurred and even disappeared, while those of wild oakleaf loquat leaves maintained their structure longer. In Zaozhong 6, cold stress induced a clear cavity between poorly structured granal thylakoids and vesicles appearing inside the chloroplast, while in oakleaf leaves cold stress had little effect on the ultrastructure of chloroplasts (although chloroplast membranes looked blurred). Loquat leaves accumulated free calcium ions around chloroplasts in response to cold stress, with earlier calcium accumulation occurring in the cold-sensitive cultivar Zaozhong 6 than in wild oakleaf loquat. These results demonstrate that these two loquat species have differences in both cold tolerance and calcium accumulation dynamics.