scholarly journals Alfalfa (Medicago sativaL.) shoot saponins: identification and bio-activity by the assessment of aphid feeding

2010 ◽  
Vol 105 (1) ◽  
pp. 62-70 ◽  
Author(s):  
H. Mazahery-Laghab ◽  
B. Yazdi-Samadi ◽  
M. Bagheri ◽  
A. R. Bagheri
Keyword(s):  
Plant Development ◽  
Insect Pests ◽  
Biological Effects ◽  
Biological Role ◽  
Growth Stages ◽  
Oral Toxicity ◽  
Medicagenic Acid ◽  
Significant Difference ◽  
Different Growth Stages

Biochemical components in alfalfa (Medicago sativaL.), such as saponins, can act as protecting factors against bio-stresses. Saponins are also antifeedants and show oral toxicity towards higher and lower animals. Changes in saponins, such as variation in the carbon skeleton, or hydrolysis of saponin glycosides and other conjugates, may change their biological effects. The aims of this research were to study saponin variation in different growth stages of alfalfa and to investigate the biological role of saponins in the spotted alfalfa aphid,Therioaphis maculata. Saponins from alfalfa shoots in different growth stages were extracted, chemically purified and analysed by TLC. Specific saponins such as soyasaponin1 from root and shoot and two bisdesmosides of medicagenic acid, one from shoot and another from root tissues, were identified using reference compounds allowing changes in saponin composition during plant development in different shoot tissues of alfalfa to be assessed. The response of the alfalfa aphid to feeding on alfalfa in different growth stages was studied. No significant difference in the survival of aphids, from neonate to adult, was observed, but due to the antibiotic effects of saponins, two differences were found in the onset of nymph production and cumulative nymph production. The results show that the saponin composition in alfalfa changes with plant development and this, in turn, can often negatively affect the development of specific insect pests such as the spotted alfalfa aphid, suggesting a possible biological role of alfalfa saponins.

scholarly journals Physicochemical Mechanisms of Synergistic Biological Action of Combinations of Aromatic Heterocyclic Compounds

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Maxim P. Evstigneev
Keyword(s):  
Heterocyclic Compounds ◽  
Biological Effects ◽  
Biological Action ◽  
Biological Role ◽  
Aromatic Molecules ◽  
Simultaneous Use ◽  
Aromatic Heterocyclic

The mechanisms of synergistic biological effects observed in the simultaneous use of aromatic heterocyclic compounds in combination are reviewed, and the specific biological role of heteroassociation of aromatic molecules is discussed.

scholarly journals Insect pests of groundnut (Arachis hypogaea L.), nature of damage and succession with the crop stages

2014 ◽  
Vol 39 (2) ◽  
pp. 273-282 ◽  
Author(s):  
GC Biswas
Keyword(s):  
Insect Pests ◽  
Leaf Miner ◽  
Growth Stages ◽  
Minor Importance ◽  
Pest Species ◽  
Common Cutworm ◽  
Leaf Roller ◽  
Arachis Hypogaea L ◽  
Extent Of Damage ◽  
Different Growth Stages

Thirty six species of insect pests were found to infest the different growth stages of groundnut crop at Gazipur, Bangladesh during the rabi seasons of 2008-09 and 2009-010. Among the recorded pest species, the hairy caterpillar, Spilarctia obliqua ( Walker); common cutworm, Spodoptera litura F.; jassid, Empoasca terminalis Distant ; leaf miner, Stomopteryx nerteria M. and leaf roller, Anersia ephippias (Meyr.) were considered as the major pests, while the rests were of minor importance on the basis of their population densities/plant, nature and extent of damage and yield reductions. Most of the major and minor pests infested during the vegetative to pre-maturity stages (45-95 DAS) and the maximum infestation occurred during pod formation and pod filling stages (50- 80 DAS) of the crop in both the years. DOI: http://dx.doi.org/10.3329/bjar.v39i2.20429 Bangladesh J. Agril. Res. 39(2): 273-282, June 2014

scholarly journals Tumor Vascular Morphology Undergoes Dramatic Changes during Outgrowth of B16 Melanoma While Proangiogenic Gene Expression Remains Unchanged

ISRN Oncology ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Elise Langenkamp ◽  
Franziska M. vom Hagen ◽  
Peter J. Zwiers ◽  
Henk E. Moorlag ◽  
Jan P. Schouten ◽  
...  
Keyword(s):  
Gene Expression ◽  
Major Change ◽  
Drug Regimen ◽  
Growth Stages ◽  
Separate Analysis ◽  
Small Vessels ◽  
Vascular Morphology ◽  
Vessel Morphology ◽  
Significant Difference ◽  
Different Growth Stages

In established tumors, angiogenic endothelial cells (ECs) coexist next to “quiescent” EC in matured vessels. We hypothesized that angio-gene expression of B16.F10 melanoma would differ depending on the growth stage. Unraveling the spatiotemporal nature thereof is essential for drug regimen design aimed to affect multiple neovascularization stages. We determined the angiogenic phenotype—represented by 52 angio-genes—and vascular morphology of small, intermediate, and large s.c. growing mouse B16.F10 tumors and demonstrated that expression of these genes did not differ between the different growth stages. Yet vascular morphology changed dramatically from small vessels without lumen in small to larger vessels with increased lumen size in intermediate/large tumors. Separate analysis of these vascular morphologies revealed a significant difference in αSMA expression in relation to vessel morphology, while no relation with VEGF, HIF-1α, nor Dll4 expression levels was observed. We conclude that the tumor vasculature remains actively engaged in angiogenesis during B16.F10 melanoma outgrowth and that the major change in tumor vascular morphology does not follow molecular concepts generated in other angiogenesis models.

scholarly journals Insect Pests Of Soybean (Glycine Max L.), Their Nature Of Damage And Succession With The Crop Stages

2013 ◽  
Vol 39 (1) ◽  
pp. 1-8 ◽  
Author(s):  
GC Biswas
Keyword(s):  
Insect Pests ◽  
Growth Stages ◽  
Minor Importance ◽  
Pest Species ◽  
Common Cutworm ◽  
Leaf Roller ◽  
Pod Borer ◽  
Glycine Max L ◽  
Ophiomyia Phaseoli ◽  
Different Growth Stages

Thirty nine species of insect pests were found to infest soybean crop at their different growth stages in Noakhali region of Bangladesh during January to May, 2010 and 2011. Among the recorded pest species, six species namely, hairy caterpillar, Spilarctia obliqua (Walker); leaf roller, Lamprosema indicata F; common cutworm, Spodoptera litura F; pod borer, Helicoverpa armigera (Hubner); stem fly, Ophiomyia phaseoli (Tryon) and white fly; Bemisia tabaci Genn. were considered as the major pests while the rests were of minor importance on the basis of population densities per plant, nature and extent of damages, and yield reductions. Most of the major and minor pests appeared in the crop during vegetative to flowering stages (30-50 Days after sowing) and the maximum insect population and their infestation occurred during flowering and pod formation stages of the crop throughout the study period. J. Asiat. Soc. Bangladesh, Sci. 39(1): 1-8, June 2013 DOI: http://dx.doi.org/10.3329/jasbs.v39i1.16027

Yield loss at the different growth stages in soybean due to insect pests in Ghana

2012 ◽  
Vol 45 (15) ◽  
pp. 1796-1809 ◽  
Author(s):  
Mumuni Abudulai ◽  
Abdulai B. Salifu ◽  
Danial Opare-Atakora ◽  
Mohammed Haruna ◽  
Nicholas N. Denwar ◽  
...  
Keyword(s):  
Yield Loss ◽  
Insect Pests ◽  
Growth Stages ◽  
Different Growth Stages

scholarly journals Evaluation of Antioxidant Capacity, Fat-Soluble Micronutrients and Glucosinolates at Different Growth Stages of a Commonly-Consumed Asian Brassica Vegetable

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 446-446
Author(s):  
Choon Nam Ong ◽  
Wee Kee Tan ◽  
Chiang Shiong Loh
Keyword(s):  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Plant Development ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Mature Stage ◽  
Growth Stages ◽  
Vitamin K1 ◽  
Leaf Stage ◽  
Total Antioxidant ◽  
Different Growth Stages

Abstract Objectives This study aimed to systematically investigate a comprehensive list of bioactive components in a commonly consumed Asian leafy vegetable, Brassica rapa. They included polyphenols, fat soluble micronutrients such as carotenoids, tocopherols and phylloquinone, and various glucosinolates (GLs), in addition to the total antioxidant capacity, at three different growth stages. Methods Phenolic compounds were measured using C-18 HPLC/MS. Carotenoids, vitamin E and phylloquinone (vitamin K1) were detected using RP-30-HPLC/MS. Glucosinolates were determined using HILIC-HPLC/MS. Different AOX capacities were assessed either using UV-Visible or Fluorescent Spectrophotometer. Results Phenolic compounds, such as total flavonoid and hydroxycinnamic acids, were highest at 3-leaf stage and significantly lower in mature plant. The main carotenoids, lutein and β-carotene, remained the same throughout the different growth stages. However, violaxanthin, neoxanthin and β-cryptoxanthin were higher also at 3-leaf stage, and decrease gradually with growth. In contrast, tocopherol concentration continued to increase and was highest at mature stage. There was little change for phylloquinone (vitamin K1) throughout the three studied stages. For the unique components in Brassicaeae, both dominating aliphatic and indolic-GLs concentrations were significantly higher at 1-leaf stage than at mature stage ( > 30x), whereas the aromatic GLs, although of much lower concentrations, continued to increase throughout the growth, and with highest amount at mature stage, suggesting that there is metabolic pathway shift of these secondary metabolites during plant development. In general, antioxidant capacity measured using Scavenging of DPPH radicals, Trolox Equivalent Antioxidant Capacity and Oxygen Radical Absorbance Capacity suggested that there was an insignificant increase of total antioxidant content from seedling to mature vegetable. Conclusions The overall findings suggest that most of the nutritional active bio-components were higher at younger stages, either at 1-leaf or 3-leaf stage, except α-tocopherol, with continual accumulation during plant development. These comprehensive profiles of various nutrients should be valuable to the nutritional community. Funding Sources National Research Foundation, Prime Minister's Office, Singapore.

scholarly journals Response of Cotton Varieties to the Stage of Topping under Rainfed Condition of Bardiya, Nepal

2006 ◽  
Vol 27 ◽  
pp. 165-168 ◽  
Author(s):  
KB Basnet
Keyword(s):  
Block Design ◽  
Growth Stages ◽  
Cotton Yield ◽  
Seed Cotton ◽  
Rainfed Condition ◽  
Seed Cotton Yield ◽  
Significant Difference ◽  
The Difference ◽  
The Impact ◽  
Different Growth Stages

A field experiment was conducted to study the impact of topping at different growth stages (3-4, 6-7, 9-10 and 12-13 sympodial branches) on productivity of two (Tamcot SP-37 and H-777) cotton varieties under rainfed condition at the Kumbher Farm (Bardiya district) of Cotton Development Board in 1995. The experiment was laid out in a Randomized Complete Block Design with four replications. The interaction effect between variety and stages of topping showed that significantly higher yield (1.23 t/ha) was produced by topping plants at the stage of 12-13 sympodial banches of the variety Tamcot SP-37 as compared to all other treatments. At all stages of topping the yield produced by Tamcot SP-37 was significantly higher than H-777. The average seed cotton yield (1.03 t/ha) of Tamcot SP-37 was significantly higher than that of H- 777 (0.71 t/ha) and the difference in yield was 45.0%. The seed-cotton yield increased from 0.75 to 1.00 t/ ha with the postponed of topping from 3-4 to 12-13 sympodial branches, but significant difference was recorded between late (12-13 sympodial branches) and early (3-4 and 6-7 sympodial branches) stages of topping. Thus, for rainfed condition of Bardiya Tamcot SP-37 was a suitable variety with 12-13 sympodial branches as an appropriate stage of topping for sustainable production of cotton. Key words: Variety, topping, sympodial branches. J. Inst. Agric. Anim. Sci. 27:165-168 (2006)

Sign in / Sign up

Export Citation Format

Share Document