Influence Of Growth Retardation Research Articles

Influence of prohexadione-calcium and paclobutrazol on growth, yield and mineral content of pear cv. Clapp’s favourite

Present investigation was carried out to study the influence of growth retardants viz., prohexadione-calcium and paclobutrazol on mineral content of pear cv. ‘Clapp’s Favourite’ during the year 2015-2016. The experiment was laid out with thirteen treatments, replicated thrice on 12 year-old-pear tree with uniform vigor and health under uniform cultural practices. The treatment comprised of single and double spray of growth retardants i.e., prohexadione-calcium (100 ppm, 200 ppm and 300 ppm) and paclobutrazol (100 ppm, 200 ppm and 300 ppm). The first spray of these growth retardants was given at complete petal fall stage and second at four weeks after first spray. The orchard soil was moderately deep with good fertility status. Results revealed that both the growth retardants had showed a significant influence on the studied characters. The plants sprayed twice with prohexadione-calcium @ 200 ppm (T9S2) recorded minimum annual shoot extension growth of 16.92 cm and leaf area (22.20 cm2) alongwith increase in fruit yield (51.24 kg). Highest value for calcium (Ca) in leaves and fruits of pear (574.00 mg & 71.24 mg, respectively) was recorded when plants were sprayed twice with prohexadione-calcium at 300 ppm. Results also revealed that application of prohexadione-calcium application at 200 ppm sprayed twice (T9S2) resulted in significant increased in potassium content of the pear leaves and fruits i.e. 98.40 mg and 22.78 mg, respectively. However minimum value for potassium content was recorded in control (T1S0). Double spray of prohexadione-calcium @ 200 ppm was effective in reducing the annual extension growth, leaf area and increasing the fruit yield and calcium and potassium content in leaves and fruit.

The influence of growth retardants and cytokinins on flowering of ornamental plants

Growth retardants are applied in order to obtain short and well compact plants. They usually inhibit stem elongation, but also can influence the flowering of plants. The aim of cytokinin application is to obtain well branched plants without removing the apical meristem. Cytokinins usually increase the number of axillary shoots but also can influence flowering. Growth retardants and cytokinins can affect flower size, pedicel length, number of flowers, flower longevity, abortion of flower buds and number of days from potting plants to the first open flower. Flowering of growth retardant and cytokinin treated plants might depend on the method of growth regulator used (foliar spray or soil drench), plant species or even a plant cultivar, but in the highest degree it depends on the growth regulator rate used. These growth regulators, when are applied at rates appropriate for height and habit control, very seldom influence flowering of ornamental plants, but applied at high rates can delay flowering, diminish flower diameter or flower pedicel length and also can decrease the number of flowers per plant. In cultivation of bulb plants, growth retardants, used at very high rates, also cause abortion of flower buds.

Influence of Growth Retardants on Serpentine Accumulation in Catharanthus roseus Cell Suspension Cultures

Influence of Growth Retardants on Serpentine Accumulation in Catharanthus roseus Cell Suspension Cultures

Bone disease in children and adolescents undergoing successful renal transplantation

Little is known about the extent and severity of bone disease in children undergoing successful renal transplantation. To address this issue, 47 patients with stable renal function 3.2 +/- 1.7 years after transplantation (Tx) underwent iliac crest bone biopsy. The mean age of patients was 12 +/- 2.0 years; 36 had received cadaveric renal grafts, whereas 11 had undergone living-related Tx. Immunosuppressive drugs included cyclosporine 0.17 +/- 0.4 mg/kg/day, prednisone 7.5 +/- 2.1 mg/kg/day, and either azathioprine 1.6 +/- 0.9 mg/kg/day or mycophenolate mofetil 30 +/- 3 mg/kg/day. In addition to quantitative bone histomorphometry, the bone mineral content (BMC) of the lumbar spine was measured by dual energy X-ray absorptiometry (DXA) in 24/47 patients. Thirty-one transplant recipients had normal bone formation (N-Bfr), 11 had mild hyperparathyroidism (HPT) and 5 had adynamic skeletal lesions (AD). The interval since Tx, duration of dialysis before Tx and cumulative prednisone dose did not differ among groups. Trabecular bone area was highest in subjects with HPT. Unexpectedly, eroded bone perimeter exceeded normal reference values both in patients with AD and in those with N-Bfr; the osteoid area and osteoid perimeter were also elevated in these two groups. Hyperparathyroidism improved or resolved after Tx in all 14 subjects with this skeletal lesion prior to Tx, but one patient developed AD after Tx. Bone histology did not change after Tx in those with N-Bfr during regular dialysis, but bone formation increased after Tx in two of three patients with AD during regular dialysis. Z-scores for height in pre-pubertal patients after Tx were below age-appropriate values in each histologic subgroup, but values did not differ among groups. Z-scores for bone mineral content at the lumbar spine were also less than age-predicted values, -0.67 +/- 1.2. After adjusting for the degree of growth retardation, height-adjusted z-scores for lumbar spine BMC after Tx were above normal in all three histologic groups (0.68 +/- 1.0). The results suggest that reductions in bone mass and post-transplant osteoporosis are not prominent findings in pediatric renal transplant recipients when the influence of growth retardation on bone mass measurements by DXA is carefully considered.

Influence of Growth Retardants and Ethylene-Generating Compounds on Culture Response of Leaf Explants from Wheat ( Triticum aestivum L.)

Summary The influence of the growth retardants LAB 150978, tetcyclacis, and chlormequat chloride (CCC), as well as the ethylene-forming compounds 2-chloroethyl-phosphonic acid (ethephon) and 1-amino-cyclopropane-1-carboxylic acid (ACC, on leaf development and culture response of basal leaf explants has been studied after in vivo treatment of donor seedlings of wheat (Triticum aestivum L. cv. Kolibri). Both classes of compounds gradually reduced shoot growth at 10−6 to 10−4 mol × L−1. However, the growth retardants delayed leaf development, e.g. the tissue zone of callus initiation of the youngest, 3rd leaf was decreased while the low competence of the 2nd leaf base was concomitantly intensified. In contrast, the ethylene-generators promoted development of an additional leaf compared to untreated plants. Since the older leaf retained its culture response and the new leaf exhibited additional callus formation (with enhanced root outgrowth), the responding tissue area and overall callus production per plant were increased by about 50 %. In contrast to the growth retardants LAB 150978 and tetcyclacis, callus proliferation was also substantially stimulated by in vitro treatment of leaf explants with ethephon. Thus, the ethylene-enhanced responsiveness of wheat leaf tissue provided more genetically identical plant material capable of cell division for in vitro culture and genetic manipulation.

Influence of growth retardants on the internode and ethylene production of sunflower plants

The growth‐retarding activity of the norbornenodiazetine tetcyclacis and the di‐oxanylalkenyl triazole LAB 150 978 as well as the ethylene‐forming compounds 2‐chloroethyl‐phosphonic acid (ethephon) and 1‐amino‐cyclopropane‐l‐carboxylic acid (ACC) on stem histogenesis and ethylene production of sunflower plants (He‐lianthus annuus L. cv.Spanners Allzweck) has been studied. The shoot growth of plants hydroponically grown and treated was reduced by the compounds. The shortening in the length of the 1st internode caused by tetcyclacis and LAB 150 978 was mainly induced by inhibition of cell division (the internode possessed fewer cortical cells per cell file). In contrast, ethephon and ACC decreased internode elongation mainly by reducing the rate of cell enlargement.The ethylene production of sunflower seedlings cultivated on agar nutrient medium rose with increasing concentrations of ethephon and ACC, the shoot length of the plants being progressively reduced.Tetcyclacis and LAB 150 978 inhibited both the formation of ethylene and shoot growth. It is suggested that in contrast to ethephon and ACC, tetcyclacis and LAB 150 978 do not achieve their growth‐retarding effect by influencing the production of ethylene.

Influence of phosfon D and cycocel on growth and essential oil content of sage and peppermint

Foliar application of Phosfon D at 50–100 ppm stimulates the growth of Salvia officinalis (sage) and moderately retards the growth of Mentha piperita (peppermint), while increasing the essential oil yield of both species by 50–70 % Phosfon D increases the proportions of (−)-3-isothujone and (+)-3-thujone in sage oil and decreases the level of (−)-β-pinene and (+)-camphor, whereas this growth retardant increases the proportions of (+)-isomenthone and (+)-neoisomenthol in peppermint oil and decreases the level of(−)-menthone and (−)-menthoL Foliar application of Cycocel at 250–500 ppm slightly stimulates growth and essential oil formation in peppermint, and retards growth of sage with little effect on oil yield. The influence of Cycocel on sage oil composition was the opposite of that of Phosfon, with a tendency to increase the level of (−)-β-pinene and decrease the level of (−)-3-isothujone under severe stunting. The effect of Cycocel on the composition of peppermint varied with concentration. The influence of growth retardants on essential oil composition and yield are most readily explained by alterations in the levels or activities of the relevant enzymes.

Fetal mediators of the relationships between increased pregnancy and labour blood pressure and newborn irritability.

A prospective study of primiparous English women and their newborns failed to replicate previous findings that greater irritability was related to higher maternal blood pressure during pregnancy and labour. This apparent lack of replication prompted a search for fetal variables capable of mediating the blood pressure--irritability relationships. Relative fetal growth retardation was found in newborns of women whose peak antenatal blood pressure occurred from 20 to 32 wk gestation. Prenatal growth retardation and exposure to either oxytocin-stimulated labour or higher maternal blood pressure during spontaneous labour were associated with lower intrapartum fetal heart rate. Lower heart rate, in turn, was associated with greater crying and more frequent changes of state during behavioural assessments on the first and fifth days. It is suggested that intrapartum hypoxia is an immediate antecedent of newborn irritability. The blood pressure--irritability relationships may therefore reflect the influence of growth retardation, attributable to increased pregnancy blood pressure, and higher labour blood pressure, respectively, on the ability of the fetus to withstand hypoxia and the degree of hypoxia encountered during labour.

Zusammenhang zwischen Intensität der Synthese von Zellwandpolysacchariden und dem Streckungswachstum von Weizenkoleoptilen unter dem Einfluß von Wachstums-regulatoren des CCC-Typs

It was investigated the influence of CCC (2-chloroethyl-trimethylammonium-chloride), hexamethonium, decamethonium and AMO-1618 on cell wall polysaccharide synthesis of wheat coleoptile segments. Under the influence of growth retardants there is no variation in the relation between 14 C-incorporation rates of the different cell wall fractions (during a 5 hours incubation period). In every case the cell elongation is more inhibited by the growth retardants than the synthesis of cell wall polysaccharides. It is supposed that treated coleoptiles contain more cell wall material per cell wall surface unit than the control.

Effect of ischemia on metabolism of the brain of the newborn mouse.

Effect of ischemia on metabolism of the brain of the newborn mouse.

Influence of Growth Retardants on Growth, Nutrient Content, and Yield of Tomato Plants Grown at Various Fertility Levels1

Abstract Tomato transplants were grown at different fertility levels in mixtures of peat moss-turface and peat moss-perlite. Growth retardants, Cycocel and Alar, were applied to young plants when they attained the 3 true leaf stage. Cycocel was more effective in reducing growth than was Alar, regardless of the fertility level. Alar was effective in reducing growth of plants in both growing media. Cycocel treated plants were more drought resistant than were the Alar-treated plants. Plants treated with either Cycocel or Alar were more drought resistant and darker green in color than control plants. Chlorophyll content was measured on Alar-treated and control plants. Alar-treated plants contained more chlorophyll, and their leaves had more palisade cells than plants of the control. Cycocel-treated plants contained more N, P, Ca, and Mg, but less K than the control plants. Alar-treated plants contained more N and P than did the control plants and more K than control plants when grown in peat moss-perlite. In only 1 of 3 experiments did Alar-treated plants contain less Ca than control plants, but the chemical had no effect on the Mg content of the plants’ stems and leaves. A single spray of Alar at 2500 ppm increased yields of early fruits in 1 of 3 experiments. In this experiment, both early fruit number and weight were increased, but the fruits were smaller than those from Cycocel treated and control plants. Growth retardants and fertility rates used in these studies had no effect on total yields, although interactions existed between growth retardants and nutrient rates in their effect on nutrient uptake.