Factor Analysis of Differences in Biomass Accumulations between Male and Female Populus Cathayana Seedlings under Drought Stress

2012 ◽  
Vol 195-196 ◽  
pp. 1308-1313
Author(s):  
Yao Chen

The main influential factor of biomass accumulations between male and female Populus cathayana seedlings was investigated from the point of factor analysis under drought stress. The results shows that biomass accumulations of seedlings under drought stress are mainly associated with stem dry mass (SDM), root dry mass (RDM), height growth (HG), basal diameter (BD), total leaf number (TLN) and other morphologic changes, and have little relation with intrinsic water use efficiency (WUE). There is sex differences in the mode of biomass accumulation between male and female plants. Biomass accumulation in female plants depends on morphologic changes, followed by hormonal regulation, and finally physiological progress. However, biomass accumulation in male plants depends on morphologic changes, followed by physiological progress, and finally hormonal regulation. Moreover, biomass accumulation in female plants on the morphologic aspects mainly depends on SDM, while is not relevant to TLN. However, male plants mainly depend on SDM, and have relationship with TLN. In sum, our study demonstrates that biomass accumulations in male and female P. cathayana seedlings under drought stress have different strategies.

2010 ◽  
Vol 58 (7) ◽  
pp. 519 ◽  
Author(s):  
Xiao Xu ◽  
Guoquan Peng ◽  
Chengchun Wu ◽  
Qingmin Han

We investigated differences between the sexes of a dioecious species, Populus cathayana Rehd, in biomass accumulation, biomass allocation, and carbon (C) and nitrogen (N) concentrations under elevated temperature treatments. Cuttings were subjected to three temperature regimes (control, +2°C and +4°C, respectively) in closed-top chambers. Compared with the control treatment, warming significantly increased the net photosynthesis rate, height growth, leaf dry mass, stem dry mass (SM), root dry mass (RM) and total dry mass (TM), and resulted in a higher aboveground : belowground dry mass ratio (AB) in all individuals of both sexes, except in males under the +2°C warming treatment. Furthermore, warming decreased the concentration of C in the stems in both sexes, and increased the concentration of N in the leaves of females, and consequently, resulted in a lower C : N ratio in the leaves of female cuttings than in those of male cuttings. Also, further differences between males and females were detected. In the warming treatments, females exhibited significantly higher values of SM, RM, TM and AB, and lower RM : TM and RM : foliage area ratios than did the males. However, no significant differences in these traits between the two sexes were detected under ambient temperature. Our results indicated that allocation of biomass, and the concentrations of C and N in males and females are greatly affected by an elevated temperature, and that warming benefits females, which accumulate and allocate more biomass to aboveground organs than do the males.


Author(s):  
Donna E. Youngs ◽  
Miroslava A. Yaneva ◽  
David V. Canter

AbstractIn the spirit of the growing developments in positive psychology, there is an increasing interest in how kind people are to each other. Yet, this area lacks any strong psychometric instrument. An initial exploratory study demonstrated that a 40-item questionnaire, completed by 165 people, revealed distinct aspects of kindness when subjected to multivariate analysis. A subsequent study is reported, using the structure of the exploratory results to further clarify the conceptual framework (Study 1). The revised 45-item questionnaire was administered to 1039 individuals from the general British population. Smallest Space Analysis of the variables, supported by Factor analysis, confirmed the hypothesis of two facets to kindness, the psychological source of the action (from principles or empathy), and the form of expression (through psychological involvement or following social prescription. It also revealed an additional general, core kindness, labelled Anthropophilia. Reliable scales derived from the combinations of the two elements from each facet were identified: Affective-Socially Prescribed; Affective-Proactive; Principle-Socially Prescribed and Principle-Proactive. Intercorrelations between the scales revealed that they measure different modes of kindness. Comparisons between male and female respondents provided external validity for the questionnaire. Study 2 (N = 251) reported that the scales measure independent dimensions when correlated with similar and dissimilar concepts.


1994 ◽  
Vol 8 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Itzhak Montag ◽  
Joseph Levin

Two studies of the Revised NEO‐Personality Inventory (NEO‐PI‐R) conducted on two different applicant samples (one consisting of 539 female subjects and the other consisting of 396 male subjects) are reported. Factor analysis of the female sample yielded a five‐factor solution, highly congruent with the factors presented by Costa, McCrae and Dye (1991). Results of the male data were less clear‐cut, yielding four to five factors which were moderately congruent with the American data. The combined male and female sample showed again high congruence coefficients. Various minor deviations in the location of the facet variables are discussed.


1980 ◽  
Vol 209 (1175) ◽  
pp. 299-315 ◽  

Aspects of the course of infection, growth and reproductive activity of Moniliformis were studied in adult male and female rats fed on iso -energetic purified diets containing various sugars. When rats were infected and fed on experimental diets containing either 3% glucose or 3% galactose for 5 weeks, very little growth of the worms and no signs of reproduction were observed. In contrast, Moniliformis grew well and showed many signs of normal reproduction when the rats were fed on diets containing either 3% fructose or 3% mannose. The ability of the worms to grow and reproduce was not lost by maintaining them first for 5 weeks in rats fed on diets containing 3% glucose and 3% galactose. When the diets of such rats were changed to ones containing 3% starch and 3% fructose, respectively, for a further 5 weeks, the worms grew and normal reproduction occurred. Similar experiments were carried out in which groups of infected rats were fed for 5 weeks on diets containing gradually increasing amounts of glucose (6-36%). It was not until the rats were fed on diets containing 24% glucose that the mean dry mass of the worms approached that of worms from rats fed on the diet con­taining 3% fructose; no host diet was found to be as effective a supporter of worm growth as 3% mannose. Under no circumstances, not even when the host’s diet contained 36%, was galactose found to be a suitable sugar for supporting the growth and reproduction of Moniliformis . Results consistent with those recorded for worms from rats fed on the diets containing monosaccharides were obtained when infected rats were fed for 5 weeks on diets containing 3% of various disaccharides. Considerable growth and reproduction of Moniliformis occurred when sucrose was included in the host’s diet, but not when lactose, maltose or trehalose was present. Several of these observations may be related to the fact that different sugars are absorbed at different rates from the intestinal tract. It is suggested that all of a given sugar, when present in the diet at a low concentration, may be removed rapidly from the anterior part of the small intestine with the result that none will be available to the parasites. Significant amounts, however, of those sugars that are absorbed more slowly may reach the region of the intestine in which the parasite normally lives.


2021 ◽  
Vol 45 ◽  
Author(s):  
Elen Silma Oliveira Cruz Ximenes ◽  
Andréa Carvalho da Silva ◽  
Adilson Pacheco de Souza ◽  
Josiane Fernandes Keffer ◽  
Alison Martins dos Anjos ◽  
...  

ABSTRACT Flame retardants are efficient in fighting wildfire; however, their environmental implications, especially regarding the vegetation, need to be clarified. This work aimed at assessing the effects of flame retardant on the initial growth of Schizolobium amazonicum. Treatments consisted in applying different flame retardant concentrations via substrate and leaf: Phos-Chek WD-881® (0, 3.00, 6.00, 8.00 and 10.00 mL L-1), Hold Fire® (0, 7.00, 9.00, 12.00 and 15.00 mL L-1) and water-retaining polymer Nutrigel® used as alternative retardant (0, 0.25, 0.50, 0.75 and 1.00 g L-1). Growth analyses were carried out to assess the effects of these substances (10 repetitions per treatment). The aliquot of 10.00 mL L-1 of Phos-Chek WD881 applied on the leaves led to an increase of 70% in leaf area and 15% in seedling height. The same Phos-Chek concentration favored height increase (32%) and total dry mass accumulation (33%) throughout time. The concentration of 15 mL L-1 of Hold Fire® applied on leaves, compromised 45% the accumulation of dry biomass in the seedling. Initially, 1.00 g L-1 of Nutrigel® applied via substrate led to an increase of 70% in leaf area, 29% in plant height, and 89% in leaf dry mass. Therefore, Phos-Chek applied on leaves favored shoot growth in S. amazonicum. Hold Fire® applied on leaves impaired biomass accumulation in seedlings. Nutrigel® applied on substrate does not cause long-lasting damage to the initial growth of S. amazonicum. The aliquot of 0.50 g L-1 administered via polymer leave had positive effect on seedling shoot.


2013 ◽  
pp. 67-80
Author(s):  
Branislav Kovacevic ◽  
Dragana Miladinovic ◽  
Marina Katanic ◽  
Zoran Tomovic ◽  
Sasa Pekec

The effect of low initial medium pH on shoot and root development of five white poplar (Populus alba L.) genotypes was tested. The shoot height, fresh mass of shoots per jar, dry mass of shoots per jar, number of roots, as well as the length of the longest root were measured and final pH of the media determined, after 35 days of culture in vitro. Three initial pH values of the medium were tested: 3.0, 4.0 and 5.5 as control. Agar solidification at pH 3.0 was not achieved after sterilization in autoclave, but it was successful after sterilizing in a microwave oven. The obtained results indicate that the tested genotypes are able to significantly influence the changes of media pH during culture. The effect of differences among the examined media was significant for biomass accumulation and final media pH. Generally, significantly higher values of fresh and dry shoot mass, shoot height and the longest root length were recorded on a medium with initial pH 3.0 then on a standard medium with pH 5.5.The implications of the obtained results for the improvement of in vitro propagation of white poplars are discussed.


2021 ◽  
Author(s):  
Bettina Rottweiler ◽  
Paul Gill

Across three studies based on a nationally representative survey (n = 1500), we developed and validated the misogyny scale. Initial items were generated from an extensive literature search and subsequently derived from validated scales assessing internalised misogyny, hostile sexism, and hostility towards women. Construct and measurement validity were established across several studies. An exploratory factor analysis (Study 1, n = 750) established the factor structure of the 10-item misogyny scale. In study 2 (n = 750), the 10-item structure was replicated via confirmatory factor analysis. The misogyny scale displayed good convergent (i.e., significant and strong relationship with male sexual entitlement, masculinity related violent beliefs and willingness to use violence) and discriminant validity (i.e., no relationship with analytical thinking). In study 3 (n = 750), we established measurement invariance across gender and age groups. This allows researchers to deploy the scale among male and female individuals, across different age groups as well as to assess latent mean differences. Significant latent mean differences for all three latent factors emerged between male and female participants, demonstrating that men had significantly stronger misogynistic attitudes than women (MDiff1 = -.482***; MDiff2 = -.324***; MDiff3 = -.197***). The latent mean differences ranged from small (Cohen’s d2 = .27; Cohen’s d3 = .19) to medium effect sizes (Cohen’s d1 = .38). The strongest latent mean differences between age groups were found for the factor ‘manipulative and exploitative nature of women’. Older age groups reported significantly stronger attitudes relating to this factor than younger participants. The misogyny scale will allow researchers to explore the psychological antecedents and consequences of misogyny among population samples and the subsequent findings may have important practical implications for prevention and intervention programs on violent (extremist) propensity development.


2019 ◽  
Vol 11 (11) ◽  
pp. 245
Author(s):  
Adriana Silva Santos ◽  
Juliana Formiga Almeida ◽  
Marcio Santos da Silva ◽  
Jackson Silva Nóbrega ◽  
Thais Batista de Queiroga ◽  
...  

The salinity in irrigation water is one of the most important causes to decline cultivated plants yield. The H2O2 application has shown efficiency as a stimulator and activator for antioxidative defense system in plants submitted to biotic and abiotic stresses. The objective of this study was to evaluate methods for hydrogen peroxide application as a strategy to minimize the effects of saline stress on melon plants. The experiment was designed in complete randomized blocks and set in 2 × 4 factorial scheme, consisting two levels for irrigation water salinity (S1 = 0.3 and S2 = 2.0 dS m-1) and four methods for hydrogen peroxide application (15 mM), (T1 = no peroxide application, T2= imbibition of seeds, T3 = at sowing, T4 = Foliar spraying), with five repetitions. It was evaluated the following variables at 58 days after transplanting: plant height, stem diameter, number of leaves, number of flowers, shoot dry mass, root dry mass and total dry mass. The results showed that salinity affected the growth, biomass accumulation and plant quality severely, with the highest losses promoted by the electrical conductivity of 2.0 dS m-1.


Author(s):  
Anie Thomas ◽  
R. Beena

Drought stress reduces photosynthetic rate and leading to depletion of the energy source and lowers the yield. Under drought stress, reduced turgor pressure cause inhibition of cell elongation and impaired mitosis leads to reduction in growth rate. Role of sucrose metabolism under drought adaptation and response of plants to stress in different tissues and at different developmental stages. Cytoplasmic sucrose synthesis is more under drought condition and there is differential expression in tolerant and susceptible cultivars. Under drought condition, plant start consuming its own sink for its survival thus reducing sucrose concentration. But reduction in sucrose concentration is less in drought tolerant plants. Drought stress induced an increase of the root/shoot ratio, which was due to the increased inhibition of biomass accumulation of shoots compared to roots. Drought stress enhanced the activities of sucrose metabolic enzymes and up-regulated the expression of genes such as SPS, SuSy and INV. In addition, drought stress up-regulated the expression levels of SWEET and SUC and promoted the transport of sucrose from source to sink.


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