scholarly journals Studies on the Effects of Gaseous Ions on Plant Growth

1962 ◽  
Vol 45 (5) ◽  
pp. 879-895 ◽  
Author(s):  
Albert P. Krueger ◽  
Sadao Kotaka ◽  
Paul C. Andriese ◽  
Keyword(s):  
Plant Growth ◽  
Avena Sativa ◽  
Current Flow ◽  
Dry Weight ◽  
Stem Length ◽  
Ion Density ◽  
Measurable Difference ◽  
Significant Stimulation ◽  
Growth Increase ◽  
Stimulation Of

Exposure of Avena sativa seedlings to unipolar ionized atmospheres of either charge produced statistically significant stimulation of growth as measured by mean stem length, integral elongation, and dry weight. The extent of growth increase was related to the atmospheric ion density and this in turn determined the magnitude of current flow to ground. The minimal current measured in the ground circuit and capable of producing a measurable difference in growth was 4.3 to 4.6 x 10-13 amp/plant.

Effect of a plant growth regulator regime on internode length and weight of tillers in conventional and hybrid rye and the impact of nitrogen on crop performance

1997 ◽  
Vol 128 (2) ◽  
pp. 143-154 ◽  
Author(s):  
M. A. FROMENT ◽  
H. G. McDONALD
Keyword(s):  
Plant Growth ◽  
Growth Regulator ◽  
Plant Growth Regulator ◽  
Unit Length ◽  
Dry Weight ◽  
Internode Length ◽  
Stem Length ◽  
Winter Rye ◽  
Crop Performance ◽  
Growth Regulator Treatment

The effect of nitrogen and a plant growth regulator regime (chlormequat chloride followed by 2-chloroethylphosphonic acid) on the crop performance of a hybrid (cv. Luchs) and a conventionally bred winter rye (cv. Sentinel) were investigated in two field experiments each year between 1993 and 1995 at Winchester, UK. Internode length and dry weight/unit length of internodes was measured in order to assess the effect of the growth regulator regime on stem structure. Grain yields were 15% higher in the hybrid Luchs than in Sentinel. With high levels of applied nitrogen, both cultivars lodged in all seasons and this was most severe in 1994 when 88% of the crop lodged in Sentinel and 52% in Luchs. Plant growth regulator treatment consistently reduced lodging but did not eliminate it. Reductions in lodging were not always associated with an increase in grain yield. In the hybrid cultivar, the growth regulator treatment reduced yield in 1993 and 1995 when 2-chloroethyl-phosphonic acid was applied at GS49 and GS39 respectively, but increased yield in 1994 when applied at GS37. Growth regulator consistently reduced stem length, and the percentage reduction in length of the individual internodes within the stem was strongly influenced by the timing of the 2-chloroethylphosphonic acid component of the PGR treatment. Growth regulator reduced internode lengths by up to 25% in Sentinel and 35% in Luchs, and this was associated with reductions in the dry weight of internodes by up to 32% in Sentinel and 38% in Luchs. Consequently, dry weight/unit length of the stem was not increased by growth regulator treatment. Yield reductions in Luchs following growth regulator treatment may have been due to reduced stem reserves which have been associated with tolerance of stress in rye. Both cultivars were highly responsive to nitrogen. Economic optima varied from season to season, but they ranged over three years, from 175–273 kg/ha nitrogen, and were greater than the currently recommended application rates. Crop lodging increased with increasing nitrogen rate even when plant growth regulator was applied and yield penalties from lodging would have been high, if weather conditions during grain maturity had been unfavourable.

FACTORS GOVERNING THE STIMULATION OF EMBRYONIC CHICK CARTILAGE BY SOMATOMEDIN

1976 ◽  
Vol 83 (2) ◽  
pp. 259-268 ◽  
Author(s):  
A. C Herington ◽  
L. S. Phillips ◽  
W. H. Daughaday
Keyword(s):  
Human Serum ◽  
Incubation Time ◽  
Dry Weight ◽  
Good Precision ◽  
Embryonic Chick ◽  
Prolonged Incubation ◽  
Significant Stimulation ◽  
Normal Human ◽  
Assay Precision ◽  
Stimulation Of

ABSTRACT In these studies of the stimulation of embryonic chick pelvic rudiments by somatomedin (Sm) in serum, we have found that cartilage weight and duration of cartilage exposure to serum determine the stimulation of cartilage by serum and the relative stimulation by Sm and by other non-Sm serum components, respectively. These factors are critical for the use of this system to measure Sm in serum. Initial experiments revealed that incorporation of sulfate (SO4) by cartilage incubated in buffer fell rapidly after 9 h and reached very low levels by 30 h. Incubation in 40 % normal human serum (NHS) produced significant stimulation of incorporation of SO4 after 4 h, and maintained at least initial levels of incorporation for 24 h. The greatest % stimulation by NHS over buffer was seen with prolonged incubation (44 h). However, specificity for Sm (discrimination between NHS and hypophysectomized human serum (HHS)) was greater with shorter incubation times. The potency of HHS was 11, 42 and 92 % of the potency of NHS following early, intermediate and late measurement of incorporation of SO4 by cartilage, respectively. The best overall results were obtained with intermediate incubation time and measurement of SO4 incorporation ((35S)-SO4 present for the final 5 h of a 25 h incubation), which allowed good precision (λ = 0.17) while maintaining satisfactory specificity for Sm. Since prolonged incubation with late measurement of SO4 incorporation allowed the greatest % stimulation by serum with little differentiation between NHS and HHS, stimulation of incorporation of SO4 under these conditions is apparently due to non-Sm factors present in both NHS and HHS. In addition to incubation time, cartilage stimulation by serum was also determined by cartilage weight. Lighter cartilage (from younger embryos) was associated with higher unstimulated incorporation of SO4 (P < 0.01), lower stimulation by added serum (P < 0.01), and inadequate assay precision (P < 0.05): satisfactory assays were generally obtained with cartilage rudiments weighing more than 0.7 mg (dry weight).

scholarly journals Persistent Effects of Plant Growth Regulators on Landscape Performance of Seed Geraniums

1994 ◽  
Vol 12 (3) ◽  
pp. 150-154
Author(s):  
Joyce G. Latimer ◽  
Sherrod A. Baden
Keyword(s):  
Plant Growth ◽  
Plant Height ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Dry Weight ◽  
Stem Length ◽  
Shoot Dry Weight ◽  
Landscape Performance ◽  
Reduced Height ◽  
Time Required

Abstract In 1988, spray applications of 3.5 or 7 ppm paclobutrazol, 1500 ppm chlormequat, or 200 ppm ancymidol were applied to seed geraniums (Pelargonium x hortorum L. H. Bailey ‘Ringo White’ and ‘Ringo Rose’) to determine effects on growth in the greenhouse and the subsequent growth and performance of treated plants in the landscape. All growth retardants reduced stem length and shoot dry weight as well as time required for flowering, while branching was increased relative to the untreated plants. Flowering in the landscape was increased by all growth regulator treatments at 4 weeks after planting but was generally not different from the untreated plants at 6 weeks after planting. Plant height and width were reduced by all treatments for both cultivars, relative to untreated plants, at 4 weeks after planting. However, only 7 ppm paclobutrazol reduced height and width of ‘Ringo White’ plants at 6 weeks after planting. Plant height, but not width, was reduced by all treatments for ‘Ringo Rose’ at 6 weeks after planting. In 1989, seedlings of ‘Ringo Rose’ were treated with 3.5, 7, 16, 40, or 80 ppm paclobutrazol or 1500 ppm chlormequat or 200 ppm ancymidol. Seedling growth was excessively reduced by 40 or 80 ppm paclobutrazol. Time required for flowering was not reduced by growth regulators in 1989. Landscape performance under conditions of excess rain was not improved by plant growth regulators and the height of plants treated with 16, 40 or 80 ppm paclobutrazol was still less than that of the untreated plants at 12 weeks after planting. Only chlormequat controlled plant growth in the greenhouse without delaying the resumption of growth in the landscape.

Growth stimulation of clusterbean (Cyamopsis tetragonoloba) by coinoculation with rhizosphere bacteria and Rhizobium

2016 ◽  
Author(s):  
Sita Ram Chaudhary ◽  
Satyavir Singh Sindhu
Keyword(s):  
Plant Growth ◽  
Aminolevulinic Acid ◽  
Arid Zone ◽  
Dry Weight ◽  
Growth Stimulation ◽  
Cyamopsis Tetragonoloba ◽  
Rhizobium Strain ◽  
Shoot Dry Weight ◽  
Bradyrhizobium Strain ◽  
Stimulation Of

Clusterbean [Cyamopsis tetragonoloba (L.) Taub.] is an important commercially utilizable crop grown in arid zone of India. Microorganisms present in the rhizosphere of this crop produce various plant growth-promoting substances and enhance the availability of nutrients to the plants. Therefore, fifty five bacterial isolates obtained from the rhizosphere of clusterbean were explored for beneficial characteristics. Twenty rhizobacterial isolates produced indole acetic acid ranging from 3.9 to 24.7 μg/mL. Only six isolates HCS7, HCS19, HFS7, HFS9, HFS10 and HFS12 showed d-aminolevulinic acid production varying from 1.3 to 7.0 μg/mL. Fourteen isolates showed solubilization of potassium on mica containing Aleksandrov medium plates. Stimulation of root and shoot growth of clusterbean seedlings on water agar plates was observed by inoculation of eleven rhizobacterial isolates at 5 and 10 days of growth whereas some isolates showed stunting effect on the growth of shoot and root as compared to uninoculated seedlings. At 60 days of plant growth, inoculation of Bradyrhizobium strain GSA11 and Rhizobium strain GSA110 showed significant nodulation and their inoculation resulted in 141.94 and 151.43% gains in shoot dry weight, respectively under chillum jar conditions. Coinoculation of Bacillus isolate HCS43 with Rhizobium strain GSA110 formed 48 nodules/plant and plant dry weight was enhanced by 190.09% in comparison to uninoculated control plants.

Using Plant Growth-promoting Fungi (PGPF), as a Biofertilizer and Biocontrol Agents against Tetranychus cucurbitacearum on Nubian Watermelon (Citrullus lanatus L.)

2019 ◽  
pp. 1-15
Author(s):  
Rabab Hammad ◽  
Mohssen Elbagory
Keyword(s):  
Plant Growth ◽  
Field Experiment ◽  
Spider Mite ◽  
Trichoderma Viride ◽  
Dry Weight ◽  
Fruit Yield ◽  
Stem Length ◽  
Growth Stages ◽  
Plant Growth Promoting ◽  
Growth Promoting

Plant growth-promoting fungi (PGPF) have attracted considerable interest as biofertilizers and biocontrol due to their multiple beneficial effects on plant quantity and quality as well as their positive relationship with the ecological environment. The objective of this study was to determine the efficacy of different concentrations 25, 50, 75 and 100% from cultural filtrate of Trichoderma viride and T. harzianum to induce the two-spotted spider mite, Tetranychus cucurbitacearum (In vitro), and their ability to improve the growth dynamics of Nubian watermelon plants in field experiment during two growing summer seasons of 2017 and 2018. In general the effect of tested concentrations of T. viride were non effective on egg deposition by adult females after five days from treatment, while in T. harzianum, the concentration 75% was the most effect than the other concentrations. Also, egg hatchability % decreased with increased of two egg age (1 – 2 day old) at treatment by concentrations 25 and 50% of both fungal. In field experiment, the test compound (vertimec) was the more effective against egg stage of spider mite T. cucurbitacearum than motile stages of both T. viride and T. harzianum treatments. Also, plants inoculated with T. harzianum showed increases in vegetative growth parameters included numbers of leaves, Leaf dry weight, stem length and numbers of branches and biochemical analysis of leaves included chlorophyll content and percentages of NPK at 30 and 60 days from sowing during both seasons compared to uninoculated control plants. Also, enzymes activities, treatment T2 (inoculated with T. viride) recorded the highest values at all growth stages, which recorded 155.77, 257.29 and 114.62 mg TPF g-1 soil day-1 for dehydrogenase and 113.79, 201.03 and 115.24 mg NH4+- N g-1 soil d-1 for urease at 30, 60 and harvest during 2017 growing season, respectively. The same trend was observed in total count of fungi during both seasons. For fruit yield, T. viride (T2) had significantly the highest number of fruits per plant, number of seeds per fruit, fruit weight (g) and dry weight of 100 seeds (g) which recorded 1.92, 273.07, 1126 g and 16.29 g as compared to untreated control treatment, which attained 1.21, 185.08, 526.66 g and 14.41 g at 2017 season, respectively. Therefore, these results reflected to increase fruit yield (Kg/m2), seed yield (g/m2) and weight of yield (ton fed.-1) during both seasons.

Stimulation of plant growth and aphid populations by a formulation ingredient of ‘Cymbush’ (cypermethrin)

1994 ◽  
Vol 84 (4) ◽  
pp. 509-513 ◽  
Author(s):  
Helen J. Hutt ◽  
H.F. van Emden ◽  
T. Baker
Keyword(s):  
Plant Growth ◽  
Intrinsic Rate ◽  
Dry Weight ◽  
Growth Stimulation ◽  
Natural Increase ◽  
Aphis Fabae ◽  
Residual Effects ◽  
Fresh Weight ◽  
Bean Plants ◽  
Stimulation Of

AbstractSimilar increases in the height and aerial fresh weight of cowpeas compared with control plants were obtained when plants were sprayed with either 50 ppm a.i. (active ingredient) of the pyrethroid insecticide ‘Cymbush’® containing cypermethrin, or, the equivalent dilution of a blank formulation without the a.i. With broad beans, similar growth stimulation was obtained with the blank at the same or half dose, but not at a quarter dose. Testing the four formulation components separately showed that only the non-ionic emulsifier caused stimulation. A comparison of the stimulation of plant growth by the blank and the non-ionic emulsifier showed that plant height, shoot fresh weight, leaf fresh weight, leaf dry weight and leaf area were each equally increased by both treatments. The non-ionic emulsifier thus accounted for the entire stimulation caused by blank solution. Populations of Aphis fabae Scopoli (Homoptera: Aphididae) were twice as high on broad bean plants sprayed with the non-ionic emulsifier as on the controls. ‘Cymbush’ (the complete formulation) sprayed at 25 ppm a.i. was shown to increase the intrinsic rate of natural increase of the aphid through a 22% increase in fecundity; aphid development time was not affected. The results do, however, suggest that residual effects of cypermethrin may have partly counteracted the stimulatory effects of the non-ionic emulsifier. Nevertheless, it is possible that outbreaks of aphids and mites following pyrethroid application, and often assumed without evidence to have been due to natural enemy mortality, may at least in part reflect the plant stimulation caused by the non-ionic emulsifier in the formulation.

scholarly journals Growth and Flowering of Salvia nemorosa ‘Ostfrieland' in Response to Reduced Irrigation1

2020 ◽  
Vol 38 (2) ◽  
pp. 63-67
Author(s):  
Amanda Bayer
Keyword(s):  
Soil Moisture ◽  
Plant Growth ◽  
Irrigation System ◽  
Control Plant ◽  
Dry Weight ◽  
Plant Production ◽  
Stem Length ◽  
Moisture Sensor ◽  
Soil Moisture Sensor ◽  
Shoot Dry Weight

Abstract Reduced irrigation (RI) can conserve water and control plant growth; however, the timing of RI applications can impact plant growth and flowering. The goal of this research was to quantify growth of Salvia nemorosa L. ‘Ostfrieland' (East Friesland) in response to RI. A soil-moisture sensor automated irrigation system was used to apply four irrigation treatments: RI and well-watered (WW) controls (20% and 38% substrate water content) and two combination treatments to apply RI for either the first two weeks (20% followed by 38%, RIWW ) or final four weeks (38% followed by 20%, WWRI ) of the six-week study. Flower number, height, compactness, and relative chlorophyll content (SPAD) were not different across treatments. Average flower stem length was greater for the WW and RIWW treatments than for the RI treatment. Shoot dry weight was less for the RI treatment compared to the WW and RIWW treatments, respectively]. Cumulative irrigation volume was lowest for the RI treatment and highest for the RIWW treatment. Visually, plants in the RIWW treatment had an open, floppy habit that would likely negatively impact sales in a retail setting. Plants in the RI treatment were smaller, but visually appealing. Index words: soil moisture sensor, plant production, herbaceous perennial, container plants. Species used in this study: ‘Ostfrieland' salvia (Salvia nemorosa L.).

scholarly journals Persistence of the biocide activity of atrazine in soils of the southeast of Buenos Aires Province

1996 ◽  
Vol 14 (2) ◽  
pp. 110-117 ◽  
Author(s):  
A.A. Delmonte ◽  
F. Bedmar ◽  
J.D. Mantecón ◽  
H. Echeverría ◽  
C.A. Barassi
Keyword(s):  
Plant Growth ◽  
Avena Sativa ◽  
Cation Exchange Capacity ◽  
Buenos Aires ◽  
Dry Weight ◽  
Exchange Capacity ◽  
Buenos Aires Province ◽  
Growth Reduction ◽  
Dry Soil ◽  
Soil Weight

Atrazine persistence in soils of the southeast of Buenos Aires Province, was studied by an oat bioassay. Atrazine doses of 0.58, 1.16, and 2.32 mg.g-1 dry soil weight (DSW) were applied to pots containing soils from Balcaree, A. Gonzáles Chaves and San Cayetano sites, whose organic matter (OM) content of soils were 5.70, 5.15, and 3,84%, respectively. Avena sativa cv. Millauquén plants were grownth in the pots under greenhouse conditions at different times after atrazine application. Shoots were evenly cut above the soil and dry weight determined as a measure of plant growth. Plants grown in non-sprayed soil were used as controls. Relative dry weight (RDW) of shoots was calculated as percentage of control. Atrazine phytotoxicity was expressed in terms of 50 % plant growth reduction (GR50) in the soils under study. Herbicide persistence was expressed in terms of days after treatment (DAT) needed for the plant to achieve 80% of RDW. Atrazine GR50 values of 0.30, 0.64, and 0.90 mg.g-1 DSW in soils from San Cayetano, Balcare and A.G. Chaves, were respectively obtained at 42 DAT. Herbicide persistences at the recommended dose (1.16 mg.g-1) were 100, 143, and 221 DAT for A.G. Chaves, Balcarce and San Cayetano soils, respectively. San Cayetano soil had both the lowest OM content and cation exchange capacity (CEC), as well as the highest pH, of all the soil studied here. These results were consistent with both the lowest GR50 and the highest persistence abtained for atrazine in this soil.

scholarly journals MECHANICAL CONDITIONING OF GREENHOUSE-GROWN TRANSPLANTS

HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 616a-616
Author(s):  
Joyce G. Latimer
Keyword(s):  
Weight Gain ◽  
Plant Growth ◽  
Large Scale ◽  
Stem Elongation ◽  
Dry Weight ◽  
Growth Retardants ◽  
Mechanical Conditioning ◽  
Shoot Dry Weight ◽  
Growth Increase ◽  
Postharvest Handling

Since chemical growth retardants are no longer labelled for use on vegetable transplants, mechanical conditioning provides an alternative method of controlling excessive stem elongation under greenhouse conditions. Mechanical conditioning includes brushing or shaking treatments that physically impact or displace the plant and generally reduce plant growth, increase stem and petiole strength, and improve overall plant quality. The resulting transplants have less breakage during postharvest handling, may be more stress tolerant, and are faster to establish in the field. However, only minor effects on crop yield have been identified. Brushing reduced broccoli transplant size, but improved shoot dry weight gain during field establishment but had no effect on head yield. Brushing is a labor intensive practice for large-scale operations. Current attempts to mechanize brushing require that the plants are uniform in height and treatment tolerant. Additional research in non-contact treatments like shaking or vibration of benches is necessary. The effects of the treatments on stress tolerance and predisposition to disease need to be clarified.

Effect of rhizobacteria strains on the induction of resistance in barley genotypes against Cochliobolus sativus

2020 ◽  
Vol 13 (2) ◽  
pp. 83-92 ◽  
Author(s):  
A. Adam
Keyword(s):  
Plant Growth ◽  
Pseudomonas Putida ◽  
Growth Parameters ◽  
Disease Incidence ◽  
Dry Weight ◽  
Cochliobolus Sativus ◽  
Resistance Level ◽  
Wet Weight ◽  
Number Of Leaves ◽  
Barley Genotypes

SummaryEnhancement of the resistance level in plants by rhizobacteria has been proven in several pathosystems. This study investigated the ability of four rhizobacteria strains (Pseudomonas putida BTP1 and Bacillus subtilis Bs2500, Bs2504 and Bs2508) to promote the growth in three barley genotypes and protect them against Cochliobolus sativus. Our results demonstrated that all tested rhizobacteria strains had a protective effect on barley genotypes Arabi Abiad, Banteng and WI2291. However, P. putida BTP1 and B. subtilis Bs2508 strains were the most effective as they reduced disease incidence by 53 and 38% (mean effect), respectively. On the other hand, there were significant differences among the rhizobacteria-treated genotypes on plant growth parameters, such as wet weight, dry weight, plant height and number of leaves. Pseudomonas putida BTP1 strain was the most effective as it significantly increased plant growth by 15-32%. In addition, the susceptible genotypes Arabi Abiad and WI2291 were the most responsive to rhizobacteria. This means that these genotypes have a high potential for increase of their resistance against the pathogen and enhancement of plant growth after the application of rhizobacteria. Consequently, barley seed treatment with the tested rhizobacteria could be considered as an effective biocontrol method against C. sativus.

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