scholarly journals Morphological and physiological variation in Toona ciliata under water and salinity stress

2020 ◽  
Vol 50 (6) ◽  
Author(s):  
Ramon Silveira de Andrade ◽  
Marcio Carlos Navroski ◽  
Mariane de Oliveira Pereira ◽  
Alexandra Cristina Schatz Sá

ABSTRACT: The objective of this paper was to test the effects of water deficit, saturation and salinity in individuals of Toona ciliata. Seven treatments were tested: the control group, the complete suspension of irrigation, the permanent saturation of the pot soil and four doses of NaCl (50, 100, 200 and 400 µmol). The experimental design was completely randomized, with 8 repetitions in each treatment. Physiologic evaluations were carried out during the experiment, and morphologic evaluations at the end. The plants were responsive to the applied stresses comparatively to the control group. Reductions were observed in morphological and physiological variables in all treatments under stress. All individuals under stress recovered slightly in the end of the experiment, and began to sprout again, representing a probable adaptation to the conditions.

2021 ◽  
Vol 51 ◽  
Author(s):  
Maria Beatriz Bernardes Soares ◽  
Juliana Altafin Galli ◽  
Monica Helena Martins ◽  
Ana Carolina Oliveira ◽  
Silvano Bianco

ABSTRACT Weed interference in young citrus orchards causes significant damages, especially when competition occurs during the dry season, when environmental resources are even more scarce. This study aimed to test the effects of interference periods and weed management on the physiology, yield and quality of Persian lime fruits, during the dry season. The experimental design was randomized blocks, with five treatments [hoeing; glyphosate application; decrease of stored water (March to May); critical water deficit (June to August); and water deficit throughout the dry season (March to August)] and four replications. Weed interference during the decrease of stored water and critical water deficit periods affected significantly the physiological variables, yield and total solids contents of the fruits, but to a lesser extent than for the water deficit throughout the dry season. Weed control with glyphosate resulted in 1.56 and 2.53 times more fruits per tree than hoeing and water deficit throughout the dry season, respectively. The chemical management provided better physiological and productive responses than hoeing, due to the effect of weed mulch in the water deficit season.


Crisis ◽  
2016 ◽  
Vol 37 (6) ◽  
pp. 415-426 ◽  
Author(s):  
Yik-Wa Law ◽  
Paul S. F. Yip ◽  
Carmen C. S. Lai ◽  
Chi Leung Kwok ◽  
Paul W. C. Wong ◽  
...  

Abstract. Background: Studies have shown that postdischarge care for self-harm patients is effective in reducing repeated suicidal behaviors. Little is known about whether volunteer support can help reduce self-harm repetition and improve psychosocial well-being. Aim: This study investigated the efficacy of volunteer support in preventing repetition of self-harm. Method: This study used a quasi-experimental design by assigning self-harm patients admitted to the emergency departments to an intervention group with volunteer support and treatment as usual (TAU) for 9 months and to a control group of TAU. Outcome measures include repetition of self-harm, suicidal ideation, hopelessness, and level of depressive and anxiety symptoms. Results: A total of 74 cases were recruited (38 participants; 36 controls). There were no significant differences in age, gender, and clinical condition between the two groups at the baseline. The intervention group showed significant improvements in hopelessness and depressive symptoms. However, the number of cases of suicide ideation and of repetition of self-harm episodes was similar for both groups at the postintervention period. Conclusion: Postdischarge care provided by volunteers showed significant improvement in hopelessness and depression. Volunteers have been commonly involved in suicide prevention services. Further research using rigorous methods is recommended for improving service quality in the long term.


2017 ◽  
Vol 17 (1) ◽  
pp. 55
Author(s):  
Ismaniar Ismaniar Ismaniar

The present study is aimed at developing effective guidance program for increasing student’s learning motivation. The present study applies quantitative research approach with nonequivalent pre-posttest control group quasi-experimental design, and nonrandom-purposive sampling technique. The data were collected using inventory, interview, and documentary study. The study comes up with the main finding that the tested guidance program is proven to be effective for increasing learning motivation students of 11th grade at SMA Kartika XIX-2 Bandung.


Author(s):  
Eka Rejeki Maha ◽  
Berlin Sibarani

This study was aimed at finding out The Effect of Applying POSSE (Predict-Organize-Search-Summarize-Evaluate) Strategy on the Students’ Reading Comprehension. This study used the experimental design. The population of this study was the students of SMA Negeri 2 Medan. There were sixty students taken as the sample of the research. This study was conducted with two randomized groups namely experimental and control group. The experimental group was taught by applying POSSE strategy while control group was taught without applying POSSE strategy. The instrument of collecting the data was multiple choice test which consists of 40 items. To obtain the reliability of the test, the researcher used Kuder-Richardson (KR-21). The calculation shows the reliability was 0.81(high). The data were analyzed by using t-test. The calculation shows that t-observed (4.76) is higher than t-table (2.00) at the level of significance (α) 0.05 with the degree of freedom (df) 58. Therefore, the null hypothesis (Ho) is rejected and alternative hypothesis (Ha) is accepted. It means that there was a significant effect of applying POSSE strategy on the students’ reading comprehension. Keywords: POSSE Strategy, Reading Comprehension.


Author(s):  
Veronika N. And Lince Sihombing

This study focused on finding out the effect of applying RAP (Read, Ask,Paraphrase) Strategy on students’ reading comprehension in reading analyticalexposition text. This study was conducted in experimental design. The populationof this research was the second year of students in SMA Swasta Katolik BudiMurni 2 Medan. There were seventy students of the second year senior highschool students as the sample of the research. This study was conducted with tworandomized groups namely Experimental Group and Control Group. Theexperimental group was taught by applying RAP Strategy, while the control groupwas taught by applying conventional strategy. The instrument of collecting thedata was multiple choice tests which consisted of 25 items. The data wereanalyzed by using t-test formula. The calculation shown that t-observed (5.36)was higher than t-table (1.994) at the level of significance (α) 0.05 with the degreeof freedom (df) 68. It means that there was a significant effect of applying RAPStrategy on students’ reading comprehension in reading analytical exposition text.


Author(s):  
Maruh Sianturi And Berlin Sibarani

This study was aimed at finding out the effect of using Noting, Interacting, Summarizing, and Prioritizing Strategy on Students’ Achievement in Reading Comprehension. This study was designed with the experimental design. The population of this study was the first year students at academic 2013/2012 of SMA swasta YP St. Paulus Martubung, Medan. There were fourty students taken as the sample of the research. The sample was divided into two groups: the first group (20 students) as the experimental group and the second group (20 students) as the control group. The experimental group was taught by Using Noting, Interacting, Summarizing, and Prioritizing Strategy, while the control group was taught by using conventional method. The instrument for collecting the data was multiple choices which consisted of 40 items. To obtain the reliability of the test, the researcher used Kuder -Richardson (KR-21) formula. The calculation showed that the reliability of the test was 0.75. The data were calculated by using t-test formula. The result of the analysis shows that t-observed (4.98) was higher than t-table (2.025) at the level of significance (α) 0.05 and the degree of freedom (df) 38. Therefore, the null hypothesis (H0) was rejected and alternative hypothesis (Ha) was accepted. It meant that teaching reading comprehension by using Noting, Interacting, Summarizing, and Prioritizing Strategy significantly affects reading comprehension.


1978 ◽  
Vol 15 (2) ◽  
pp. 214-219 ◽  
Author(s):  
Charles M. Futrell ◽  
Omer C. Jenkins

On the basis of a “before-after with control group” experimental design, empirical evidence is provided that shows the amount of information disclosed about pay had a major impact on salesmen's performance and job satisfaction.


Author(s):  
E. Pagán ◽  
J.M. Robles ◽  
A. Temnani ◽  
P. Berríos ◽  
P. Botía ◽  
...  

2018 ◽  
Vol 26 (0) ◽  
Author(s):  
Ana Cláudia Mesquita Garcia ◽  
Talita Prado Simão-Miranda ◽  
Ana Maria Pimenta Carvalho ◽  
Paula Condé Lamparelli Elias ◽  
Maria da Graça Pereira ◽  
...  

ABSTRACT Objective: To investigate the effect of therapeutic listening on state anxiety and surgical fears in preoperative colorectal cancer patients. Method: A randomized controlled trial with 50 patients randomly allocated in the intervention group (therapeutic listening) (n = 25) or in the control group (n = 25). The study evaluated the changes in the variables state anxiety, surgical fears and physiological variables (salivary alpha-amylase, salivary cortisol, heart rate, respiratory rate and blood pressure). Results: In the comparison of the variables in the control and intervention groups in pre- and post-intervention, differences between the two periods for the variables cortisol (p=0.043), heart rate (p=0.034) and surgical fears (p=0.030) were found in the control group, which presented reduction in the values of these variables. Conclusion: There was no reduction in the levels of the variables state anxiety and surgical fears resulting from the therapeutic listening intervention, either through the physiological or psychological indicators. However, the contact with the researcher during data collection, without stimulus to reflect on the situation, may have generated the results of the control group. Clinical Trial Registration: NCT02455128.


2012 ◽  
Vol 152 (1) ◽  
pp. 104-118 ◽  
Author(s):  
M. DE A. SILVA ◽  
J. L. JIFON ◽  
J. A. G. DA SILVA ◽  
C. M. DOS SANTOS ◽  
V. SHARMA

SUMMARYThe relationships between physiological variables and sugarcane productivity under water deficit conditions were investigated in field studies during 2005 and 2006 in Weslaco, Texas, USA. A total of 78 genotypes and two commercial varieties were studied, one of which was drought-tolerant (TCP93-4245) and the other drought-sensitive (TCP87-3388). All genotypes were subjected to two irrigation regimes: a control well-watered treatment (wet) and a moderate water-deficit stress (dry) treatment for a period of 90 days. Maximum quantum efficiency of photosystem II (Fv/Fm), estimated chlorophyll content (SPAD index), leaf temperature (LT), leaf relative water content (RWC) and productivity were measured. The productivity of all genotypes was, on average, affected negatively; however, certain genotypes did not suffer significant reduction. Under water deficit, the productivity of the genotypes was positively and significantly correlated with Fv/Fm, SPAD index and RWC, while LT had a negative correlation. These findings suggest that genotypes exhibiting traits of high RWC values, high chlorophyll contents and high photosynthetic radiation use efficiency under low moisture availability should be targeted for selection and variety development in programmes aimed at improving sugarcane for drought prone environments.


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