scholarly journals Back to Basics: Does Seed Size Affect Germination and Plant Uniformity in Broccoli (Brassica Oleracea var Italica)?

Proceedings ◽  
2020 ◽  
Vol 36 (1) ◽  
pp. 181
Author(s):  
Celia van Sprang ◽  
Gayathri Rajagopal
Keyword(s):  
Brassica Oleracea ◽  
Seed Size ◽  
Abiotic Factors ◽  
Crop Growth ◽  
Significant Difference ◽  
Field Uniformity ◽  
Direct Seeded ◽  
Subsequent Crop ◽  
Size Variability ◽  
The Impact

Hand harvested crops, such as brassicas and lettuce, are prone to high levels of variability during growth and at harvest. This necessitates multiple harvest passes and substantially increased labour costs for the grower. Both biotic and abiotic factors contribute to this lack of field uniformity. The main objective was to evaluate the impact of broccoli (Brassica oleracea var. Italica) seed size variability on germination, subsequent crop growth and harvest uniformity. An initial experiment was conducted where germination counts across three seed-size categories including, 2.0mm (SS1), 2.3 mm (SS2) and 2.45 mm (SS3), were recorded at 3, 7, 10 and 14 days after sowing (DAS). At 14 DAS, germination was greater in the SS1 (95%) and SS2 (91%) than the SS3 (66%) (P < 0.005). A second experiment evaluated the same seed categories planted under direct seeded (DS) and transplanted (TR) conditions to identify differences in crop growth and development. At 49 DAS, DS plant counts per plot were lowest for the SS3 (54.5 plants plot−1) compared with the SS1 (70.5 plants plot−1) and SS2 (64 plants plot−1). This could be attributed to the reduced seed coat thickness evident in the SS3 (66.3 μm) which can potentially lead to increased damage and mortality of the seed, compared with the SS1 (79.3 μm) and SS2 (73.1 μm). The TR treatment gave greater uniformity with no significant difference (P < 0.05) in plant populations across seed size categories (SS1 = 95, SS2 = 90 and SS3 = 96 plants plot−1).

scholarly journals Sediment properties and CO<sub>2</sub> efflux from intact and cleared temperate mangrove forests

2015 ◽  
Vol 12 (20) ◽  
pp. 6169-6180 ◽  
Author(s):  
R. H. Bulmer ◽  
C. J. Lundquist ◽  
L. Schwendenmann
Keyword(s):  
New Zealand ◽  
Mangrove Forest ◽  
Abiotic Factors ◽  
Co2 Uptake ◽  
Co2 Efflux ◽  
Mangrove Forests ◽  
Sediment Grain Size ◽  
Significant Difference ◽  
Main Factors ◽  
The Impact

Abstract. Temperate mangrove forests in New Zealand have increased in area over recent decades. Expansion of temperate mangroves in New Zealand is associated with perceived loss of other estuarine habitats, and decreased recreational and amenity values, resulting in clearing of mangrove forests. In the tropics, changes in sediment characteristics and carbon efflux have been reported following mangrove clearance. This is the first study in temperate mangrove (Avicennia marina) forests investigating the impact of clearing on sediment CO2 efflux and associated biotic and abiotic factors. Sediment CO2 efflux rates from intact (168.5 ± 45.8 mmol m−2 d−1) and cleared (133.9 ± 37.2 mmol m−2 d−1) mangrove forests in New Zealand are comparable to rates measured in tropical mangrove forests. We did not find a significant difference in sediment CO2 efflux rates between intact and cleared temperate mangrove forests. Pre-shading the sediment for more than 30 min prior to dark chamber measurements was found to have no significant effect on sediment CO2 efflux. This suggests that the continuation of photosynthetic CO2 uptake by biofilm communities was not occurring after placement of dark chambers. Rather, above-ground mangrove biomass, sediment temperature and chlorophyll a concentration were the main factors explaining the variability in sediment CO2 efflux in intact mangrove forests. The main factors influencing sediment CO2 efflux in cleared mangrove forest sites were sediment organic carbon concentration, nitrogen concentration and sediment grain size. Our results show that greater consideration should be given regarding the rate of carbon released from mangrove forest following clearance and the relative contribution to global carbon emissions.

scholarly journals Evaluating The Impact of Roads On The Diversity Pattern And Density of Trees To Improve The Conservation of Species

2021 ◽  
Author(s):  
Uzair Aslam Bhatti ◽  
Zhaoyuan Yu ◽  
Linwang Yuan ◽  
Luo Wen ◽  
Saqib Ali Nawaz ◽  
...  
Keyword(s):  
Native Species ◽  
Management Practices ◽  
Urban Forest ◽  
Abiotic Factors ◽  
Pairwise Distance ◽  
Ecological Environment ◽  
Plant Management ◽  
Diversity Pattern ◽  
Significant Difference ◽  
The Impact

Abstract Roads have a great impact on the structure and functioning of the diversity pattern in an ecological environment and play the role of altering biotic and abiotic factors. Clusters of plants grow along the roadside due to the interplay between the arrival of propagule and seedling establishment, which depends on the road’s specifications, land pattern, and road administration and protection practices. It is very important to study the diversity pattern in a metropolitan city to improve the ecological environment. Karachi is one of the world’s largest and fastest-growing metropolitan cities; however, little is known about the urban forest of the area. In Karachi, which is in the province of Sindh, Pakistan, roadside trees along various road types (e.g., wide, medium and narrow roads) have been studied. Based on a field study, various measures of diversity were utilized to investigate the diversity of tree species on different types of paths. A total of 180 plots, divided into three primary road groups, were surveyed. The highest quantity of tree biomass per unit area was found on wide roads, followed by medium roads. On narrow roads, the least biomass was detected. A single species or a limited number of species dominated the diversity of species. Conocarpus erectus was the most dominant non-native species along all types of roads, followed by the species Guaiacum officinale. A total of 76 species (32 non-native and 44 native) that were selectively spread along the roadsides of the city were studied. There was a significant difference in phylogenetic diversity (PD), phylogenetic mean pairwise distance (MPD) and phylogenetic mean nearest taxon distance (MNTD) between wide, medium, and narrow roads. Management practices have a significant positive correlation with diversity indices. Our study identified patterns of diversity in roadside trees in Karachi. It provided the basis for future plant conservation planning, such as the conservation of plant species, the maintenance of plant habitats, and the coordination of plant management in Karachi.

scholarly journals Phenotypic (Fruit and Seed Characters) Selection of Dacryodes edulis (Don. G. Lam H. J.) Tree for Vegetative Propagation

2021 ◽  
Vol 5 (2) ◽  
pp. 347-353
Author(s):  
H.O. Okonkwo ◽  
R.E. Ubaekwe ◽  
A.N. Okeke ◽  
L.C. Malizu
Keyword(s):  
Seed Size ◽  
Vegetative Propagation ◽  
Fruit Size ◽  
Pairwise Comparison ◽  
Phenotypic Characters ◽  
Normality Test ◽  
Randomized Design ◽  
Significant Difference ◽  
Size Variability ◽  
Rivers State

The study was conducted to identify superior D. edulis trees using phenotypic characters (fruit and seed size) as the criteria to select candidate trees for subsequent multiplication through vegetative propagation. Five D. edulis compound trees were randomly selected within Onne community in Eleme LGA Rivers state in a preliminary effort to assist households in the selection and multiplication of desirable tree phenotypes. Seeds were extracted by softening fruit with warm water at 57oC. Fruit and seed length (mm), breadth (mm), and thickness (mm) were taken using veneer caliper. Size of fruit and seed was calculated as: length × breadth × thickness. The experiment was a completely randomized design in its layout and data analysis was carried out using analysis of variance and regression after a normality test was conducted using Shapiro-Wilk. The results showed that highest mean fruit size (79.38 ± 3.99 mm) was recorded in tree 3 and the lowest was tree 5 (29.60 ± 1.48 mm): while, highest seed size (34.78 ± 2.47 mm) was recorded in tree 3 and the lowest in tree 4 (15.58 ± 0.99 mm). Highest within tree fruit size variability was recorded in tree 1 (24%) and the lowest in tree 4 (12%): while the highest within tree seed size variability was recorded in tree 2 (28%) and the lowest in tree 5 (15%). There was however a significant difference in fruit and seed size between the trees. Pairwise comparison showed that tree 1 was not significantly different from tree 2 in fruit and seed size. There was a significant positive correlation between fruit and seed size among the trees. This implies that selection for large fruit size automatically selects for large seeds size. Large fruited trees can therefore be multiplied from these trees using vegetative propagation.

scholarly journals CORN GLUTEN MEAL: ALTERNATIVE WEED CONTROL FOR SQUASH

HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 884e-884
Author(s):  
Charles L. Webber ◽  
James W. Shrefler
Keyword(s):  
Soil Surface ◽  
Application Rate ◽  
Vegetable Crops ◽  
Corn Gluten Meal ◽  
Plant Survival ◽  
Application Rates ◽  
Significant Difference ◽  
Corn Gluten ◽  
Direct Seeded ◽  
The Impact

Corn gluten meal (CGM) has been identified as a potential organic preemergence and preplant-incorporated herbicide. It is an environmentally friendly material that has demonstrated ability to decrease seedling development and plant survival by inhibiting root and shoot development. Unfortunately, CGM can also decrease the development and plant survival of direct-seeded vegetable crops. As a result, the use of CGM is not recommended in conjunction with direct-seeded vegetables. The development of equipment to apply CGM in banded configurations has created an opportunity to investigate whether banded CGM applications will provide significant crop safety for direct-seeded vegetables. The objective of this research was to determine the impact of banded CGM applications on squash plant survival and yields. A factorial field study was conducted during the summer of 2004 on 81-cm-wide raised beds at Lane, Okla., with two application configurations (banded and solid), two CGM formulations (powdered and granulated), two incorporation treatments (incorporated and non-incorporated), and three application rates (250, 500, and 750 g·m–2). The two CGM formulations at three application rates were uniformly applied in both banded and solid patterns on 18 Aug. The banded application created a 7.6-cm-wide CGM-free planting zone in the middle of the raised bed. The CGM applications were then either incorporated into the top 2.5 to 5.0 cm of the soil surface with a rolling cultivator or left undisturbed on the soil surface. `Lemondrop' summer squash (Cucurbita pepo L.) was then direct-seeded into the center of the raised beds. When averaged across the other factors, there was not a significant difference between powdered and granulated CGM formulations or incorporating and non-incorporating the CGM for either squash plant survival or yields. CGM application rates made a significant difference for both squash survival and yields, when averaged across all other factors. As the CGM application rate increased, the plant survival and yields decreased. When averaged across all other factors, the banded application resulted in significantly greater crop safety (59% plant survival) and yields (228 cartons/ha) than the solid applications (25% plant survival and 118 cartons/ha). The research demonstrated the potential usefulness of CGM in direct-seeded squash production, if used in a banded application configuration. Additional research should further investigate the interaction of CGM application rates and the width of the CGM-free zone on crop safety for various vegetables.

scholarly journals SQUASH PRODUCTION AND ORGANIC WEED CONTROL

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 515A-515
Author(s):  
Charles L. Webber ◽  
James W. Shrefler
Keyword(s):  
Weed Control ◽  
Soil Surface ◽  
Plant Survival ◽  
Application Rates ◽  
Summer Squash ◽  
Significant Difference ◽  
Corn Gluten ◽  
Direct Seeded ◽  
Raised Bed ◽  
The Impact

Although CGM has been identified as an organic herbicide for weed control in turf and established vegetable plants, direct contact with vegetable seeds can decrease crop seedling development and plant survival by inhibiting root and shoot development. The objective of this research was to determine the impact of banded corn gluten meal applications on squash plant survival and yields. This factorial field study was conducted during Summer 2005 on 81-cm-wide raised beds at Lane, Okla., with two application configurations (banded and solid), two CGM formulations (powdered and granulated), two incorporation treatments (incorporated and nonincorporated), and three application rates (250, 500, and 750 g·m–2). The two CGM formulations at three application rates were uniformly applied in both banded and solid patterns on 19 Aug. The banded application created a 7.6-cm wide CGM-free planting zone in the middle of the raised bed. The CGM applications were then either incorporated into the top 2.5 to 5.0 cm of the soil surface with a rolling cultivator or left undisturbed on the soil surface. `Lemondrop' summer squash (Cucurbita pepo L.) was then direct-seeded into the center of the raised beds. When averaged across the other factors, there was no significant difference between powdered and granulated CGM formulations or incorporating and nonincorporating the CGM for either squash plant survival or yields. As the CGM application rates increased the plant survival and yields decreased. Banded application resulted in significantly greater crop safety (90% plant survival) and yields (445 cartons/ha) than the broadcast (solid) applications (45% plant survival and 314 cartons/ha). The research demonstrated the potential usefulness of CGM in direct-seeded squash production, if used in banded application configuration.

scholarly journals Biodiversity of mangrove aquatic fauna in Purworejo, Central Java, Indonesia

2017 ◽  
Vol 18 (4) ◽  
pp. 1344-1352
Author(s):  
WIRYANTO WIRYANTO ◽  
SUNARTO SUNARTO ◽  
SLAMET MARDIYANTO RAHAYU
Keyword(s):  
Abiotic Factors ◽  
Pearson Correlation ◽  
T Test ◽  
Line Transect ◽  
Correlation Test ◽  
Aquatic Fauna ◽  
Central Java ◽  
Significant Difference ◽  
Pearson Correlation Test ◽  
The Impact

Wiryanto, Sunarto, Rahayu SM. 2017. Biodiversity of mangrove aquatic fauna in Purworejo, Central Java, Indonesia. Biodiversitas 18: 1344-1352. Mangrove areas have important roles of ecologic, socio-economic, and socio-culture in ecosystem. Mangrove areas in Purworejo go into degradation as an impact of illegal logging, fishpond area expansion, settlements expansion and extension of agriculture area. All of the activities will influence the communities’ structure of mangroves vegetation and aquatic fauna. The purposes of research are to observe (i) biodiversity of mangroves aquatic fauna; (ii) correlation between mangrove vegetation and aquatic fauna; and (iii) the influence of abiotic factors towards biotic condition in research sites. This research was conducted in June-September 2016 at 3 stations and was determined with purposive sampling method. The research stations are Gedangan (Station 1), Jatikontal (Station 2) and Ngentak (Station 3). Vegetation of mangrove and aquatic fauna were observed with method of line transect and sampling removal. Association between variables (vegetation and aquatic fauna) is analyzed with Pearson Correlation Test. Influence of abiotic factors (physics and chemicals) on biotic (vegetation and aquatic fauna) is analyzed with t-test and regression test. According to the research, 34 species of aquatic fauna are from mangroves area of Purworejo. Highest value of aquatic fauna is found in Station 3 (ID 2.50). Pearson correlation test between vegetation and aquatic fauna obtains r value of 0,104. The t-test results a significant difference (sig 0.000) between abiotic factors and biotic condition and shows the impact of changes on both. Further test with regression method also indicates a weak impact on changes on abiotic factors towards biotic condition (r2 0.032).

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

Characterizing the impact of recovering sea otters on commercially important crabs in California estuaries

2020 ◽  
Vol 655 ◽  
pp. 123-137
Author(s):  
TM Grimes ◽  
MT Tinker ◽  
BB Hughes ◽  
KE Boyer ◽  
L Needles ◽  
...  
Keyword(s):  
Abiotic Factors ◽  
Sea Otter ◽  
Dungeness Crab ◽  
Sea Otters ◽  
Elkhorn Slough ◽  
Enhydra Lutris Nereis ◽  
Crab Abundance ◽  
Population Sizes ◽  
Commercially Important ◽  
The Impact

Protective legislation and management have led to an increase in California’s sea otter Enhydra lutris nereis population. While sea otter recovery has been linked to ecosystem benefits, sea otter predation may negatively affect commercially valuable species. Understanding the potential influence of sea otters is of particular importance as their range expands into estuaries that function as nurseries for commercially valuable species like Dungeness crab Metacarcinus magister. We consider how sea otter predation has affected the abundance and size of juvenile Dungeness crab in Elkhorn Slough, California, USA, and analyzed cancrid crab abundance and size across 4 California estuaries with and without sea otters to understand how biotic and abiotic factors contribute to observed variation in crab size and abundance. We compared trends in southern sea otters relative to Dungeness crab landings in California to assess whether increasing sea otter abundance have negatively impacted landings. In Elkhorn Slough, juvenile Dungeness crab abundance and size have declined since 2012, coinciding with sea otter population growth. However, the impact of sea otters on juvenile Dungeness crab size was habitat-specific and only significant in unvegetated habitat. Across estuaries, we found that cancrid crab abundance and size were negatively associated with sea otter presence. While abiotic factors varied among estuaries, these factors explained little of the observed variation in crab abundance or size. Although we found evidence that sea otters can have localized effects on cancrid crab populations within estuaries, we found no evidence that southern sea otters, at recent population sizes, have negatively impacted Dungeness crab landings in California from 2000-2014.

Implicit and explicit corrective feedback and feedback exposure conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 3-48
Author(s):  
Takehiro Iizuka ◽  
Kimi Nakatsukasa
Keyword(s):  
Explicit Knowledge ◽  
Corrective Feedback ◽  
Significant Difference ◽  
Oral Corrective Feedback ◽  
Post Test ◽  
Picture Description ◽  
Potential Factors ◽  
Implicit And Explicit ◽  
Instructional Settings ◽  
The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

2020 ◽  
Vol 20 (2) ◽  
pp. 101-120
Author(s):  
Ayça Aktaç Gürbüz ◽  
Orçun YORULMAZ ◽  
Gülşah DURNA
Keyword(s):  
Obsessive Compulsive Disorder ◽  
Intervention Program ◽  
Controlled Trial ◽  
Community Sample ◽  
Case Vignette ◽  
Control Group ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Significant Difference ◽  
The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

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