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Effects of gibberellin mutations on in vitro shoot bud regeneration of Arabidopsis
X Zhang, Z Wu, C Huang
African Journal of Biotechnology , 2008,
Abstract: Tissue culture provides a useful system to investigate how plant hormones are involved in this process. Auxin and cytokinin are widely used in plant regeneration. Gibberellin is also an important plant hormone in regulating plant growth and development. It is interesting to know the effects of gibberellin and its signalling pathway on plant regeneration. In this report Arabidopsis thaliana landsberg (wild type), ga1-3 (gibberellin biosynthesis deficiency mutant), gai (gibberellin insensitive mutant), penta mutant (lacking GA1, GAI, RGA, RGL1, RGL2) and tetra mutant (lacking GAI, RGA, RGL1, RGL2) were used as materials to investigate how plant regeneration progress was affected in these mutants under different conditions. The results showed that more shoot buds were regenerated in ga1-3 and gai than in wild type, penta and tetra mutant in the normal shoot induction medium. The frequency of shoot bud regeneration in different mutants also varied remarkably when auxin : cytokinin ratio in the medium changed. Only penta mutant had shoot bud regeneration without auxin in the medium. When the ratio increased wild type, ga1-3 and gai had higher performance in shoot bud regeneration than penta mutant. When cytokinin level increased from 0.1 to 0.5 mg l-1, shoot bud regeneration frequency of ga1-3, wild type and tetra increased remarkably except for that of penta and gai. Only the shoot bud regeneration frequency of gai did not change significantly when cytokinin level increased from 0.5 to 5 mg l-1. These gibberellin-related mutants also responded differently to NPA (an auxin polar transport inhibitor) in plant regeneration. Our results indicate gibberellin and its related pathway are also involved in plant organogenesis: gibberellin inhibitor and auxin polar transport inhibitor can promote plant organogenesis. This might provide a new way for the regeneration of recalcitrant species.
Novel Cytokinin Derivatives Do Not Show Negative Effects on Root Growth and Proliferation in Submicromolar Range  [PDF]
Kate?ina Podle?áková, David Zalabák, Mária ?udejková, Ond?ej Plíhal, Lucie Szü?ová, Karel Dole?al, Luká? Spíchal, Miroslav Strnad, Petr Galuszka
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0039293
Abstract: Background When applied to a nutrition solution or agar media, the non-substituted aromatic cytokinins caused thickening and shortening of the primary root, had an inhibitory effect on lateral root branching, and even showed some negative effects on development of the aerial part at as low as a 10 nanomolar concentration. Novel analogues of aromatic cytokinins ranking among topolins substituted on N9-atom of adenine by tetrahydropyranyl or 4-chlorobutyl group have been prepared and tested in standardized cytokinin bioassays [1]. Those showing comparable activities with N6-benzylaminopurine were further tested in planta. Methodology/Principal Findings The main aim of the study was to explain molecular mechanism of function of novel cytokinin derivatives on plant development. Precise quantification of cytokinin content and profiling of genes involved in cytokinin metabolism and perception in treated plants revealed several aspects of different action of m-methoxytopolin base and its substituted derivative on plant development. In contrast to standard cytokinins, N9- tetrahydropyranyl derivative of m-topolin and its methoxy-counterpart showed the negative effects on root development only at three orders of magnitude higher concentrations. Moreover, the methoxy-derivative demonstrates a positive effect on lateral root branching and leaf emerging in a nanomolar range of concentrations, in comparison with untreated plants. Conclusions/Significance Tetrahydropyranyl substitution at N9-position of cytokinin purine ring significantly enhances acropetal transport of a given cytokinins. Together with the methoxy-substitution, impedes accumulation of non-active cytokinin glucoside forms in roots, allows gradual release of the active base, and has a significant effect on the distribution and amount of endogenous isoprenoid cytokinins in different plant tissues. The utilization of novel aromatic cytokinin derivatives can distinctively improve expected hormonal effects in plant propagation techniques in the future.
Effects of Plant Growth Regulator on Endogenous Hormone Levels during the Period of the Red Globe Growth  [cached]
Juan He,Songlin Yu,Chao Ma
Journal of Agricultural Science , 2009, DOI: 10.5539/jas.v1n1p92
Abstract: Objective. The present study was aimed to elucidate the dynamic changes of endogenous hormone levels during the fruit growth and the changing regulation of endogenous hormone levels between normal and abnormal fruits. Methods. After using exogenous GA3 and GA3+6-BA, endogenous hormone levels such as indoleacetic acid(IAA), cytokinin(ZR), abscisic acid(ABA) and gibberellin(GA3) in normal fruits and rigid abnormal ones were determined by enzyme-linked immunosorbent assays(ELISA), respectively. Results. The results indicated that the treatments of 20mg/kg GA3 and the combination of 20mg/kg GA3+10 mg/kg 6-BA had no remarkable effects on increasing average weight of berries where the vertical diameter of grape fruits was longer than the transverse diameter. Exogenous hormone GA3 and GA3+6-BA mixture also affected the endogenous hormone levels. The content of IAA, ABA and ZR was lower in the rigid abnormal fruits than that in the normal ones, respectively, and those levels during the rapid growth period were nearly in accordance with those during the slow growth period. Conclusion. The fruit growth was closely related to the endogenous hormone levels.
Effect of plant growth regulators on indices of growth analysis for sweet passion fruit seedlings (Passiflora alata Curtis)
Tainara Bortolucci Ferrari,Gisela Ferreira,Valdir Zucareli,Carmen Sílvia Fernandes Boaro
Biotemas , 2008,
Abstract: The objective of this work was to investigate the effects of GA3 + IBA + cinetina on the growth of Passiflora alata Curtis plants through growth analysis. The experiment was carried out by completely randomized block design, with six treatments and four replications. The plant growth regulators, gibberellin (GA3), auxin (IBA) and cytokinin (kinetin), were applied to leaves at concentrations of 0 (control), 25, 50, 75, 100, 125mL.L-1. The applications were performed at 48, 55, 52, 69, and 76 days after the emergence of the plants and the growths were evaluated five times at 7-day intervals. The first evaluations were accomplished 55 days after plant emergence. The leaf area ratio (RAF), specific leaf area (AFE), liquid assimilation rate (TCA), and relative growth rate (TCR) were analyzed. The following data were also analyzed for P. alata Curtis plants: leaf area, leaf lamina dry mass and total leaves dry mass. The growth analysis, which employed the ANACRES computer program, indicated that the growth regulators increased plant productivity.
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2007,
Abstract: Pot and field trials were carried out on the roof top garden of the Department of Crop Protection and Environmental Biology, University of Ibadan, respectively the University Teaching and Research Farm, in order to study the effects of nutrient foliar spray on soybean growth and yield. TGX 1740-2F soybean variety was used in the experiment; nutrients were foliarly applied as exclusively N, NPK and NPKMg at the early flowering and early pod-filling growth stages. Plants were sprayed at the rate of 100 mg/L of water corresponding to each nutrient, while unsprayed plants served as control. The experimental design was a split plot with four replications. Results from the experiments showed that nutrient foliar spray, either singly or in combination, significantly (P= 0.05) enhanced the growth and yield of the TGX 1740-2F soybean variety, at the two growth stages. However, spraying nutrients during an early pod filling stage was significantly (P= 0.05) better than spraying at the early flowering growth stage. The highest yield of soybean was obtained by spraying NPK and NPKMg, but the optimum yield of soybean was obtained by spraying NPK at the pod filling stage of growth.
Effects of Some Plant Growth Regulators and Nutrient Complexes on Pod Shattering and Yield Losses of Soybean under Hot and Dry Conditions  [PDF]
Leyla Gulluoglu,Halis Arioglu,Mehmet Arslan
Asian Journal of Plant Sciences , 2006,
Abstract: This study was carried out to determine the effects of four Plant Growth Regulators (PGRs) (Atonik, GA3, Cytozyme Crop Extra and Megahix), two nutrient complexes (Biomaster and Kinetic) and a see weed extract (Maxicrop) on pod-shattering rate and yield loss of both main and double-cropped soybean grown in a prolonged hot and dry condition in 2002 and 2003. The soybean cultivar was A 3935. The experimental design was randomized complete block with four replications. Application of PGRs remarkably lowered the shattering rates and seed yield losses only for main-cropped soybean. The lowest shattering rates and yield losses were obtained from Atonik and Cytozyme applications until 10 days after R8 growth stage for main-cropped soybean. The positive effects of PGRs on shattering rate and yield losses were decreased with the increasing delay of harvest. The results of the current study showed that seed yield losses of main-cropped soybean could be alleviated by the application of Atonik, Megahix and Cytozyme. However application of PGRs was not suggested for double-cropped soybean if the scope was to reduce yield losses caused by pod shattering.
The Effects of Dietary of Soybean Lecithin on the Growth Performance Feed Conversion and Body Composition of Tilapia (Oreochromis niloticus L.) Fry
Hasan H. Ata,Suleyman Bekcan,Murtaza Olmez
Journal of Animal and Veterinary Advances , 2012,
Abstract: Tilapias are one of the most important domesticated fish today. Production widely distributed around the world. Lecithin also known as Phosphatidyicholine (PC), is a special type of lipid (a phospholipid) found naturally in the body. Research has shown that crustaceans and fish cannot adequately synthesise the phospholipids they require for maximum performance. Therefore, phospholipids must be added to their diet. Therefore, the experiment was designed to evaluate the effects of soybean lecithin on the growth and performance of feed conversion in Tilapia fry. The experimental period was planned as a 3 months period. Twenty one aquariums (7 groups-3 replicates) were used and 25 fish were stocked at the rate of 200 fish m-3 in each aquarium, by a completely randomized design. The effects of supplementary feeding of the tilapia (Oreochromis niloticus) fry with feeds enriched with soybean lecithin were evaluated by adding soybean lecithin to the basal diet at the rate of 1-5%. The fish were fed for 90 days to check the growth, protein efficiency ratio, feed conversion ratio, body composition and survival ratio. At the end of experiment, the best live weight increase was found to be 3% protein efficiency ratio and the feed conversion ratio was found to be 1.90 and 1.75, respectively in the 2% lecithin-treated group, supplementing soybean lecithin at the rate of 4 and 5%, which enhanced the fat content of treated fish (p<0.05).
Effects of Crop Residues of Sunflower (Helianthus annuus), Maize (Zea mays L.) and Soybean (Glycine max) on Growth and Seed Yields of Sunflower
K. Srisa-ard
Pakistan Journal of Biological Sciences , 2007,
Abstract: This pot experiment was carried out at Suranaree Technology University Experimental Farm, Northeast Thailand to investigate effects of crop residues of sunflower, maize and soybean on total dry weight, top dry weight, plant height, root dry weight and seed yield of sunflower plants with the use of Korat soil series (Oxic Paleustults) during the rainy season (July-October) of the 2001. The experiment was laid in a split plot arranged in a Completely Randomized Design (CRD) with four replications where the crop residues of maize, sunflower and soybean were used as main plots. Whilst crop residues of roots, top growth and roots+top growth were used as subplots. The results showed that crop residues derived from roots of both sunflower and soybean plants had their significant inhibition effects of allelopathic substances on plant height, root dry weight, top growth dry weight and total dry weight plant-1 of the sunflower plants than those derived from top growth of both crops alone (sunflower and soybean). Maize plant residues had no significant inhibition effect on growth of subsequent crop of sunflower.
Effects of Some Plant Growth Regulators and Nutrient Complexes on Above-ground Biomass and Seed Yield of Soybean Grown under Heat-stressed Environment  [PDF]
Leyla Gulluoglu,Halis Arioglu,Mehmet Arslan
Journal of Agronomy , 2006,
Abstract: A two-year study was conducted to determine the effects of some Plant Growth Regulators (PGRs) and nutrient complexes on biomass weight, seed yield and yield components of both main and double cropped soybean grown under hot and dry conditions. The experimental design was Randomized Complete Block with four replications. Atonik, Biomaster, GA3, Kinetic, Maxicrop, Cytozyme and Megahix were used as plant growth regulators. The soybean cultivar was A3935 (MG III). Application of PGRs had different effects on biomass weight, seed yield and yield components of both main and double cropped soybean. The highest biomass weight (1054.0 g-2) was obtained from Maxicrop and the lowest (891.8 g-2) was obtained from Megahix applied plots in main cropped soybean. Under double crop conditions, however, the highest biomass weight (857.6 g-2) was obtained from Cytozyme and the lowest (780.0 g-2) was obtained from control. Application of PGRs increased the seed yield and yield components of soybean under both main and double cropped conditions. The highest seed yield was obtained from Atonik with 3876 kg ha-1 for main crop soybean and 47 kg ha-1 for double cropped soybean. The lowest seed yields were obtained from no chemical applied control plots of both main and double cropped soybean with 3386 and 838 kg ha-1, respectively. Application of Atonik, Cytozyme and Maxicrop could be suggested to alleviate heat stress and increase seed yield of both main and double cropped soybean grown under hot and dry conditions.
Comparative effects of Apron plus 50DS and soil amendment on the growth, yield and food components of soybean
AA Adegbite, GO Agbaje, LO Adegbite, LB Taiwo, RO Awodoyin
African Journal of Biotechnology , 2005,
Abstract: Comparative effects of Apron plus 50DS (a systemic fungicide) and soil amendment (poultry droppings) on growth yield and food components of soybean (TGX 1485-1D) were studied. Soybean seeds treated with recommended dose of Apron plus 50DS had lower percentage germination when compared to the other treatments while the untreated seeds (control) had the highest percentage germination. Seeds treated with Apron plus and planted on amended soil gave the best performance in terms of development and yield. Biochemical analysis of harvested seeds showed an increase in protein content of seeds treated with recommended dose of Apron plus, planted on amended soil. Seeds treated with less than the recommended dose had the highest percentage carbohydrate content, while untreated seeds planted on amended soil had the lowest carbohydrate content. The control experiment had the highest percentage crude fibre while the lowest was recorded for seeds treated with recommended dose of Apron plus, planted on amended soil. However, there is no significant difference among the treatments in percentage ash and moisture content.
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