scholarly journals Coordination of leaf hydraulic, anatomical, and economical traits in tomato seedlings acclimation to long-term drought

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shuang Li ◽  
Abdoul Kader Mounkaila Hamani ◽  
Yingying Zhang ◽  
Yueping Liang ◽  
Yang Gao ◽  
...  
Keyword(s):  
Hydraulic Structure ◽  
Principal Component ◽  
Dry Mass ◽  
Spongy Mesophyll ◽  
Tomato Seedlings ◽  
Mesophyll Structure ◽  
Leaf Dry Mass ◽  
Major Vein ◽  
Leaf Density

Abstract Background Leaf hydraulic and economics traits are critical for balancing plant water and CO2 exchange, and their relationship has been widely studied. Leaf anatomical traits determine the efficiency of CO2 diffusion within mesophyll structure. However, it remains unclear whether leaf anatomical traits are associated with leaf hydraulic and economics traits acclimation to long-term drought. Results To address this knowledge gap, eight hydraulic traits, including stomatal and venation structures, four economics traits, including leaf dry mass per area (LMA) and the ratio between palisade and spongy mesophyll thickness (PT/ST), and four anatomical traits related to CO2 diffusion were measured in tomato seedlings under the long-term drought conditions. Redundancy analysis indicated that the long-term drought decreased stomatal conductance (gs) mainly due to a synchronized reduction in hydraulic structure such as leaf hydraulic conductance (Kleaf) and major vein width. Simultaneously, stomatal aperture on the adaxial surface and minor vein density (VDminor) also contributed a lot to this reduction. The decreases in mesophyll thickness (Tmes) and chlorophyll surface area exposed to leaf intercellular air spaces (Sc/S) were primarily responsible for the decline of mesophyll conductance (gm) thereby affecting photosynthesis. Drought increased leaf density (LD) thus limited CO2 diffusion. In addition, LMA may not be important in regulating gm in tomato under drought. Principal component analysis revealed that main anatomical traits such as Tmes and Sc/S were positively correlated to Kleaf, VDminor and leaf thickness (LT), while negatively associated with PT/ST. Conclusions These findings indicated that leaf anatomy plays an important role in maintaining the balance between water supply and CO2 diffusion responses to drought. There was a strong coordination between leaf hydraulic, anatomical, and economical traits in tomato seedlings acclimation to long-term drought.

scholarly journals Frequency and Timing of Leaf Removal Affect Growth and Podophyllotoxin Content of American Mayapple in Shade

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 582-585 ◽  
Author(s):  
Kent E. Cushman ◽  
Rita M. Moraes ◽  
Patrick D. Gerard ◽  
Ebru Bedir ◽  
Bladimiro Silva ◽  
...  
Keyword(s):  
Leaf Age ◽  
Dry Mass ◽  
Leaf Removal ◽  
Harvest Frequency ◽  
Total Leaf ◽  
Leaf Dry Mass ◽  
Long Term Performance ◽  
Term Performance ◽  
Early Harvest

Leaves of American mayapple (Podophyllum peltatum) are being investigated as an alternative and renewable source of podophyllotoxin, a pharmaceutical compound used in the manufacture of several drugs. This study examined long-term performance of mayapple populations subjected to different harvest strategies. A naturally occurring population in shade was subjected to leaf removal treatments of frequency (every year, every 2nd or 3rd year) or timing (early or late season). Plots were 1.0 m2, established during Spring 2001, and treatments were applied from 2001 to 2004. Control plots not previously harvested were also included each year. Plants did not tolerate the severest of leaf removal treatments: early harvest time in combination with annual harvest frequency. Early annual harvests reduced total leaf dry mass and total leaf area in a quadratic manner. Late harvest conducted annually, and early harvest conducted every other year, also reduced leaf dry mass and area but not as much as early annual harvest. Plants harvested every year, early, or early every year produced fewer sexual shoots than other treatment combinations. Contents of α-peltatin, β-peltatin, and total lignans were higher for leaves harvested early than those harvested late during each year of the study, demonstrating that lignan contents were affected by leaf age and not treatment. In conclusion, our results for plants grown in shade show that leaves can be removed late in the growing season every 2nd or 3rd year or early every 3rd year without reducing long-term performance of the population. This is more restrictive than that reported for populations in full sun where plants tolerated late harvests every year.

scholarly journals Leaf morphoanatomy of four red grapevine cultivars grown under the same terroir

2018 ◽  
Vol 50 ◽  
pp. 01038
Author(s):  
Ana Monteiro ◽  
Generosa Teixeira ◽  
Cristina Santos ◽  
Carlos M. Lopes
Keyword(s):  
Dry Weight ◽  
Leaf Traits ◽  
Lower Surface ◽  
Dry Mass ◽  
Lower Percentage ◽  
Cabernet Sauvignon ◽  
Large Variability ◽  
Single Leaf ◽  
Leaf Dry Mass ◽  
Leaf Density

This study compare leaf morphoanatomical characteristics of four red cultivars - ‘Touriga Nacional’, ‘Trindadeira’, ‘Cabernet Sauvignon’ and ‘Syrah’ -, grown side by side at the same terroir. The analyzed leaf traits, under light and scanning electron microscopy, showed large variability among genotypes. ‘Trincadeira’ has the biggest single leaf area and ‘Cabernet Sauvignon’ the smallest one. ‘Touriga Nacional’ showed the lowest leaf dry weight and ‘Trincadeira’ the highest one, nonetheless there was no significantly differences in leaf dry mass per area and in leaf density. Leaf dry mass per area was positively correlated with leaf density but showed no correlation with leaf thickness. The French genotypes presented higher thickness of the leaf anatomical traits than the two Portuguese ones. ‘Trincadeira’ showed significantly highest stomata density while the other cultivars showed no significant differences among them. The analyses of the three types of stomata revealed that ‘Trincadeira’ has the lower percentage of raised above and the highest percentage of sunken stomata while ‘Cabernet Sauvignon’ showed the opposite behaviour. The hairs on the lower surface presented a similar woolly aspect in all cultivars. The possible role of leaf morphoanatomical characteristics in determining the cultivars adaptation to abiotic stresses is suggested and discussed.

scholarly journals Substrate and quality mangosteen seedlings

2019 ◽  
Vol 41 (3) ◽  
Author(s):  
Gedeon Almeida Gomes Júnior ◽  
Rafaela Alves Pereira ◽  
Danillo José dos Santos ◽  
George Andrade Sodré ◽  
Eduardo Gross
Keyword(s):  
Growth Rate ◽  
Quality Index ◽  
Principal Component ◽  
Dry Mass ◽  
Seedling Production ◽  
Coconut Fiber ◽  
Garcinia Mangostana ◽  
Leaf Dry Mass ◽  
Response Groups ◽  
Dickson Quality Index

Abstract An obstacle to the production of mangosteen seedlings (Garcinia mangostana L.) is the long nursery time of approximately two years. Among other factors, the identification of a suitable substrate for seedling production from this species is a preponderant factor to reduce nursery time. This study aimed to evaluate the growth of seminal mangosteen seedlings grown in four different substrate compositions. Growth rate was determined using the following variables: stem diameter, plant height, stem dry mass, leaf dry mass, shoot dry mass, root dry mass, total dry mass and Dickson Quality Index (DQI). The substrate S1 (sphagnum turf and vermiculite) was superior to substrates S2 (pinus bark and vermiculite), S3 (pinus bark and coconut fiber) and S4 (soil) in all evaluated parameters. The principal component analysis separated the treatments into three response groups, in which S1 exerted the greatest influence on the growth variables, concluding that this one of the substrates tested was the most adequate for the formation of mangosteen seedlings.

scholarly journals Myopic Savings Behaviour of Future Polish Pensioners

Risks ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 36
Author(s):  
Sonia Buchholtz ◽  
Jan Gąska ◽  
Marek Góra
Keyword(s):  
Logistic Models ◽  
Principal Component ◽  
Social Institutions ◽  
Health Seeking ◽  
Future Health ◽  
Policy Makers ◽  
Second Best ◽  
External Assistance ◽  
Old Age Poverty

Low saving rates combined with low effective retirement age herald old-age poverty. This paper examines the preferred strategies of future Polish pensioners in order to sustain the standard of living in the future. A two-step approach is used: as a first-best strategy, we explore determinants of supplementary saving with binary logistic models; as a second-best strategy, we examine alternative options with principal component analysis. Future retirees rarely accumulate long-term savings, do not use dedicated instruments, and they start to save additionally far too late. Savings are concentrated in wealthier and better educated groups. Such myopia is governed by their political stance and not by awareness of dire prospects. Second-best strategies are based on optimistic assumptions about future health (seeking for additional jobs), on the assumed generosity of acquaintances or social institutions (relying on external assistance), or on rebelling. Given the increasing political power of elder generations, balancing the interests of workers and retirees will be an increasingly difficult task for policy makers.

Reliability Parameters Forecasting for Transmission Lines Based on Principal Component Regression

2013 ◽  
Vol 291-294 ◽  
pp. 2381-2386 ◽  
Author(s):  
Wen Xia Liu ◽  
Ji Kai Xu ◽  
Hong Yuan Jiang ◽  
Yong Tao Shen
Keyword(s):  
Principal Component Analysis ◽  
Transmission Lines ◽  
Principal Component Regression ◽  
Principal Component ◽  
Forecasting Accuracy ◽  
Factors Affecting ◽  
Reliability Parameters ◽  
Impacting Factors ◽  
Simulation Results

It is the foundation for evaluating the reliability of transmission lines to obtain and analyze the original reliability parameters. However, these parameters depend on long- term statistic and calculation. In the case of lacking such parameters in a new project , this paper proposes a method of Principal Component Analysis to obtain the principal component of the impacting factors ,in which various factors affecting reliability parameters are taken into account. Through this method, we can use PCR to obtain the failure rate of the unknown transmission lines on the base of the known credible lines’ rates. The simulation results show that the proposed approach possesses higher forecasting accuracy and provides references for the power system dispatching departments and transmission lines maintenance departments.

Financial Inclusion and CO2 Emissions in Asia: Implications for Environmental Sustainability

2021 ◽  
Author(s):  
Shahzad Hussain ◽  
Tanveer Ahmad ◽  
Syed Jawad Hussain Shahzad
Keyword(s):  
Carbon Emissions ◽  
Environmental Sustainability ◽  
Principal Component ◽  
Financial Inclusion ◽  
Causality Test ◽  
Policy Makers ◽  
Long Term Impact ◽  
Sustainable Economic Growth ◽  
The Relationship

Abstract We examine the relationship between financial inclusion and carbon emissions. For this purpose, we develop a composite indicator of financial inclusion based on a broad set of attributes through principal component analysis (PCA) for 26 countries in the Asia region. Our robust panel regression analysis reveals a significant positive long-term impact of financial inclusion on carbon emissions. The pairwise causality test reveals unidirectional long-term causality running from financial inclusion to carbon emissions. The study suggests that policy makers may design policies that integrate accessible financial systems into climate change adaptation strategies in order to neutralize the side effect of financial inclusion deteriorating environmental quality and inclusive sustainable economic growth. JEL ClassificationO16; O44, Q54

scholarly journals Long-Term River Water Quality Trends and Pollution Source Apportionment in Taiwan

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1394 ◽  
Author(s):  
Marsha Putri ◽  
Chao-Hsun Lou ◽  
Mat Syai’in ◽  
Shang-Hsin Ou ◽  
Yu-Chun Wang
Keyword(s):  
Water Pollution ◽  
Water Quality ◽  
Heavy Metal ◽  
Cluster Analysis ◽  
River Water ◽  
Principal Component ◽  
Pollution Level ◽  
Metal Levels ◽  
Metal Monitoring

The application of multivariate statistical techniques including cluster analysis and principal component analysis-multiple linear regression (PCA-MLR) was successfully used to classify the river pollution level in Taiwan and identify possible pollution sources. Water quality and heavy metal monitoring data from the Taiwan Environmental Protection Administration (EPA) was evaluated for 14 major rivers in four regions of Taiwan with the Erren River classified as the most polluted river in the country. Biochemical oxygen demand (6.1 ± 2.38), ammonia (3.48 ± 3.23), and total phosphate (0.65 ± 0.38) mg/L concentration in this river was the highest of the 14 rivers evaluated. In addition, heavy metal levels in the following rivers exceeded the Taiwan EPA standard limit (lead: 0.01, copper: 0.03, and manganese: 0.03) mg/L concentration: lead-in the Dongshan (0.02 ± 0.09), Jhuoshuei (0.03 ± 0.03), and Xinhuwei Rivers (0.02 ± 0.02) mg/L; copper: in the Dahan (0.036 ± 0.097), Laojie (0.06 ± 1.77), and Erren Rivers are (0.05 ± 0.158) mg/L; manganese: in all rivers. A total 72% of the water pollution in the Erren River was estimated to originate from industrial sources, 16% from domestic black water, and 12% from natural sources and runoff from other tributaries. Our research demonstrated that applying PCA-MLR and cluster analysis on long-term monitoring water quality would provide integrated information for river water pollution management and future policy making.

Static and dynamic postural control in long-term microgravity: evidence of a dual adaptation

2001 ◽  
Vol 90 (1) ◽  
pp. 205-215 ◽  
Author(s):  
Guido Baroni ◽  
Alessandra Pedrocchi ◽  
Giancarlo Ferrigno ◽  
Jean Massion ◽  
Antonio Pedotti
Keyword(s):  
Postural Control ◽  
Time Course ◽  
Center Of Mass ◽  
Three Dimensional ◽  
Principal Component ◽  
Movement Analysis ◽  
Trunk Flexion ◽  
Dynamic Movement ◽  
Static Body

The adaptation of dynamic movement-posture coordination during forward trunk bending was investigated in long-term weightlessness. Three-dimensional movement analysis was carried out in two astronauts during a 4-mo microgravity exposure. The principal component analysis was applied to joint-angle kinematics for the assessment of angular synergies. The anteroposterior center of mass (CM) displacement accompanying trunk flexion was also quantified. The results reveal that subjects kept typically terrestrial strategies of movement-posture coordination. The temporary disruption of joint-angular synergies observed at subjects' first in-flight session was promptly recovered when repetitive sessions in flight were analyzed. The CM anteroposterior shift was consistently <3–4 cm, suggesting that subjects could dynamically control the CM position throughout the whole flight. This is in contrast to the observed profound microgravity-induced disruption of the quasi-static body orientation and initial CM positioning. Although this study was based on only two subjects, evidence is provided that static and dynamic postural control might be under two separate mechanisms, adapting with their specific time course to the constraints of microgravity.

scholarly journals Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation

1999 ◽  
Vol 34 (6) ◽  
pp. 944-952 ◽  
Author(s):  
Moacyr Bernardino Dias-Filho
Keyword(s):  
Leaf Area ◽  
Weed Management ◽  
Dry Mass ◽  
High Light ◽  
Low Light ◽  
Light Regimes ◽  
Leaf Dry Mass ◽  
Lower Ability ◽  
Total Plant ◽  
Plant Dry Mass

Ipomoea asarifolia (Desr.) Roem. & Schultz (Convolvulaceae) and Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), two weeds found in pastures and crop areas in Brazilian Amazonia, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹) and low (200-350 µmol m-² s-¹) light regimes during a 40-day period. For both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. High-light S. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. Relative growth rate (RGR) in I. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days). In S. cayennensis, RGR was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days). These results are discussed in relation to their ecological and weed management implications.

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