The Effect of Plant Growth Regulators on Physico-Chemical Properties of Safflower (Carthamus tinctorius L.) Derived Biodiesel

Global concerns about the environmental impact of combustion emissions from petroleum fuels influence new research to seek for alternative energy sources. The current study investigates the possibility of using safflower (Carthamus tinctorius L.) as an alternative biodiesel raw material. Four plant growth regulators (PGR) were used to boost the production of safflower. Thirteen treatments were constituted from the four plant regulators and applied to the safflower crop arranged in completely randomised design, repeated three times. The results show that the effect of plant growth regulators was not more than that of the control. More studies have to be channelled towards the relationship between safflower and plant growth regulators.

Combining ectomycorrhizal fungi and plant growth-promoting rhizobacteria to enhance salt tolerance of Metasequoia glyptostroboides

Plant growth and productivity are negatively affected by soil salinity.This study investigated the effects of the rhizosphere-promoting bacterium,Bacillus paramycoides JYZ-SD5,and the ectomycorrhizal fungus,Schizophyllum commune Be,on the growth of Metasequoia glyptostroboides under salt stress.Changes in biomass,root growth,root ion distribution and in vivo enzyme activities were determined under different treatments(Be,JYZ-SD5,and Be+JYZ-SD5).The results show that all inoculations increased chlorophyll content,shoot length and root diameter with or without salt stress,and the effect of Be+JYZ-SD5was the strongest.JYZ-SD5 and Be+JYZ-SD5 treatments significantly increased root length,surface area,bifurcation number,tip number,main root length and diameter under salt stress.Normal chloroplast structures developed under both single and double inoculations.Relative to the control,root activities of M.glyptostroboides in the Be,JYZSD5,and Be+JYZ-SD5 treatments increased by 31.3%,17.2%,and 33.7%.All treatments increased the activities of superoxide dismutase(SOD),peroxidase(POD),Na^(+)-K^(+)-ATPase and Ca^(2+)-Mg^(2+)-ATPase.The strongest effect was by Be+JYZ-SD5.Analysis of root ion distribution showed that,under salt stress,Na^(+)and K^(+)decreased and were concentrated in the epidermis or cortex.Na/K ratios also decreased.The Be+JYZ-SD5 treatment increased betaine by 130.3%and 97.9%under 50 mM and 100 mM salt stress,respectively.Together,these changes result in the activation of physiological and biochemical processes involved in the mitigation of salinity-induced stress in M.glyptostroboides.

Functions of Plant Growth Substances in the Growth of Dendrobium officinale Kimura et Migo

[Objectives] To study the effects of plant growth substance on the growth and development of Dendrobium officinale Kimura et Migo. [Methods] Comparative methods were applied to study the effects of plant growth substance on the growth and development of D. officinale Kimura et Migo. [Results] Plant growth regulators play an important role in the process of tissue culture rapid propagation of D. officinale Kimura et Migo,and the main regulatory pathways are as follows.( i) Plant growth regulators promote the growth and development of D. officinale Kimura et Migo through regulating the changes of its endogenous hormones.( ii) Plant growth regulators affect the accumulation of polysaccharide content in D. officinale Kimura et Migo through regulating the changes in chlorophyll content and enzymes involved in sucrose metabolism.( iii) Plant growth regulators can increase the activity of antioxidant enzymes of D. officinale Kimura et Migo,to increase its stress resistance. [Conclusions]Using molecular biology techniques,combined with the changes of plant hormones in D. officinale Kimura et Migo,and analysis on key enzyme in the synthesis of plant hormones and gene expression,it is feasible to study the rules o changes in the content of active content of D. officinale Kimura et Migo.

Advanced Backcross QTL Analysis for the Whole Plant Growth Duration Salt Tolerance in Rice(Oryza sativa L.)

Salinity is a major factor limiting rice yield in coastal areas of Asia. To facilitate breeding salt tolerant rice varieties, the wholeplant growth duration salt tolerance（ST） was genetically dissected by phenotyping two sets of BC2F5 introgression lines（ILs） for four yield traits under severe natural salt stress and non-stress filed conditions using SSR markers and the methods of advanced backcross QTL（AB-QTL） analysis and selective introgression. Many QTLs affecting four yield traits under salt stress and nonstress conditions were identified, most（〉90%） of which were clustered in 13 genomic regions of the rice genome and involved in complex epistasis. Most QTLs affecting yield traits were differentially expressed under salt stress and non-stress conditions. Our results suggested that genetics complementarily provides an adequate explanation for the hidden genetic diversity for ST observed in both IL populations. Some promising Huanghuazhan（HHZ） ILs with favorable donor alleles at multiple QTLs and significantly improved yield traits under salt stress and non-stress conditions were identified, providing excellent materials and relevant genetic information for improving rice ST by marker-assisted selection（MAS） or genome selection.

A meta-analysis of experimental warming effects on woody plant growth and photosynthesis in forests

Increasing field experiments have been conducted in forests to better understand the response of plant growth and photosynthesis to climatic warming. However,it is still unknown whether there is a general pattern in relation to how and to what extent warming impacts woody plants in forests. In this study, a meta-analysis was conducted to investigate the warming effects. When temperatures increased between 0.3 and 10 ℃, specific leaf area(SLA) was significantly increased by 5.9%, plant height by 7.8%, biomass by 21.9%, foliar calcium(Ca) and manganese(Mn) concentrations by 20.7% and 39.6% and net photosynthetic rate(Pn) by 9.9%. Enhanced growth and Pn may have a relationship with changing SLA, efficiency of PSⅡ(photosystem Ⅱ), photosynthetic pigment concentrations and foliar nutrients. The results will be useful to understand the underlying mechanisms of forests responding to global warming.

Effects of vegetable oil residue after soil extraction on physical-chemical properties of sandy soil and plant growth

Vegetable oil has the ability to extract polycyclic aromatic hydrocarbons(PAHs)from contaminated sandy soil for a remediation purpose,with some of the oil remaining in the soil.Although most of the PAHs were removed,the risk of residue oil in the soil was not known.The objective of this study was to evaluate the effects of the vegetable oil residue on higher plant growth and sandy soil properties after soil extraction for a better understanding of the soil remediation.Addition of sunflower oil and column ex...

Effects of plant growth regulators, carbon sources and pH values on callus induction in Aquilaria malaccensis leaf explants and characteristics of the resultant calli

The endangered tropical tree, Aquilaria malaccensis, produces agarwood for use in fragrance and medicines. Efforts are currently un-derway to produce valuable agarwood compoundsn tissue culture. The purpose of this study was to develop an optimal growth medium, specif-ically, the best hormone combination for callus suspension culture. Using nursery-grown A. malaccensis, sterilized leaf explants were first incu-bated on basic Murashige and Skoog （MS） gel medium containing 15g/L sucrose and at pH 5.7. Different auxin types including 1-naphthaleneacetic acid （NAA）, 2,4-dichlorophenoxyacetic acid （2,4-D）, and indole-3-butyric acid （IBA）, were tested at various concentrations （0.55, 1.1 and 1.65 μM） using the basic medium. Leaf explants were incubated for 30 days in the dark. Callus induced by 1.1 μM NAA had the highest biomass dry weight （DW） of 17.3 mg;however the callus was of a compact type. This auxin concentration was then combined with either 6-benzylaminopurine （BAP） or kinetin at 0.55, 1.1, 2.2 or 3.3 μM to induce growth of friable callus. The 1.1μM NAA＋2.2μM BAP com-bination produced friable callus with the highest biomass （93.3mg DW）. When testing the different carbon sources and pHs, sucrose at 15g/L and pH at 5.7 yielded highest biomasses at 87.7mg and 83mg DW, respec-tively. Microscopic observations revealed the arrangement of the friable cells as loosely packed with relatively large cells, while for the compact callus, the cells were small and densely packed. We concluded that MS medium containing 15 g/L sucrose, 1.1 μM NAA ＋ 2.2 μM BAP hor-mone combination, and a pH of 5.7 was highly effective for inducing friable callus from leaf explants of A. malaccensis for the purpose of establishing cell suspension culture.

Research Progress on Nitrogen Use and Plant Growth

The application of nitrogen （N） fertilizers in agriculture has been increasing dramatically since 1970s. However, the over-fertilization causes could cause environmental problems, as well as low N use efficiency （NUE）. Promoting NUE in plants and minimizing the environmental impacts of N fertilizers had been the focus of the current research. We reviewed the importance of N, N metabolism and plant growth, plant N physiology and the molecular aspect of N metabolism in this paper. The future development of N use and NUE of plants was also discussed.

Utilizing the γ-Irradiated Sodium Alginate as a Plant Growth Promoter for Enhancing the Growth,Physiological Activities,and Alkaloids Production in Catharanthus roseus L.

Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate （ISA）,viz.,deionized water （control,T0）,20 （T1）,40 （T2）,60 （T3）,80 （T4）,and 100 ppm （T5） on the agricultural performance of Catharanthus roseus L.（Rosea） in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.

Rice plant growth and yield: foliar application of plasma activated water

Plasma activated water(PAW)was prepared for 10 min to be applied one tofive times as a foliar spray to rice plants,to investigate plant growth,yield and the concentrations of total soluble protein and sugar in the rice grains produced.The results reveal that(1)the plant height,stem diameter,dry weight,chlorophyll and total carotene concentrations were improved by∼15%,∼25%,∼24%,∼47%and∼45%,respectively,with respect to control,(2)defense mechanisms of the plants treated with PAW were improved,(3)concentrations of total soluble protein and sugar were enhanced in the rice grains of PAW treated plants and(4)yield was increased by∼14%.

Synthesis,Crystal Structure and Plant Growth Regulatory Activity of 1-(3-Amino-[1,2,4]triazol-1-yl)-3,3-dimethyl-butan-2-one

The title compound 1-（3-amino-[1,2,4]triazol-1-yl）-3,3-dimethyl-butan-2-one（3） was synthesized by Hofmann-alkylation reaction of 1-chloro-3,3-dimethyl-butan-2-one（1） and ~1H-[1,2,4]triazol-3-ylamine（2） with equal amount of K_2CO_3 as acid acceptor. The structure of compound 3 was characterized by ~1H NMR, 13 C NMR, HRMS and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group P21/n with a = 5.7227（8）, b = 27.924（4）, c = 6.2282（7） ？, β = 101.892（11）°, V = 973.9（2） ？~3, Z = 4, T = 180.00（10） K, μ（MoKα） = 0.087 mm^（-1）, Dc = 1.243 g/cm^3, 3832 reflections measured（3.648≤θ≤26.022°）, 1916 unique reflections（Rint = 0.0359, Rsigma = 0.0572） used in all calculations. The final R = 0.0557（I 〉 2σ（I）） and w R = 0.1276（all data）. Bioassay showed that 3 displayed excellent activity as plant growth regulator with inducing lateral root formation and enhancing primary root elongation at 0.27 mmol/L（50 ppm） in soybeen（He Feng-50）. Good water solubility was found with 50 mg in 1 m L of water. Therefore, application of 3 in agriculture is more environmentally friendly due to cosolvent-free condition, and results in improved abiotic-stress tolerance by affecting the root growth. And furthermore, it can be used as a precursor to investigate the function of regulating plant root growth.

STUDIES ON STEROIDAL PLANT GROWTH REGULATOR 24. STEREOCONTROLLED CONSTRUCTION OF THE SIDE CHAIN OF BRASSINOLIDE AND HOMOBRASSINOLIDE VIA A TANDEM VICINAL DIALKYLATION OF PYRANONE MOIETY

A stereocontrolled construction of the side chain of brassinclide and homobrassinolide has been achieved via the tandem vicinal dialkylation of the pyranone moiety as a key step.

Determination of Residual Amount of 15 Plant Growth Regulators in Bean Sprouts by HPLC-MS/MS

[Objectives]This study was conducted to effectively monitor PGR residues in bean sprouts to provide guarantee for the food safety of agricultural products.[Methods]A high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method for the determination of residues of 15 plant growth regulators(PGRs)in bean sprouts was established using bean sprouts as an experimental material.Samples were extracted with a solution containing 5%acetic acid-acetonitrile(1∶99,V/V),purified with anhydrous magnesium sulfate,and diluted with methanol solvent to constant volume.The solutions were filtered through 0.22μm filtering membrane and the target analytes were separated on a Phenomenex H18 column.The identification of each compound was established by retention time matching along with the accurate mass measurement of the precursor ions and their main fragment ions.The quantification was carried out using matrix-matched external standard method.[Results]The retention time of the 15 PGRs were found in the range from 5.8-11.7 min under the optimized conditions.The linear relation was good in the concentration range of 0.005-0.050μg/ml,and the correlation coefficients of the 15 PGRs were≥0.9990.The limits of detection were in the range of 0.03-0.92 g/kg,and the limits of quantification were in the range of 0.50-2.10μg/kg.The average recovery in the recovery test at 3 concentration levels was 80%-110%,and the relative standard deviations were in the range of 2.8%-7.5%.[Conclusions]This method is simple and accurate,and can quickly qualitatively and quantitatively analyze the residues of 15 PGRs in bean sprouts.The proposed procedure was simple,quick and accurate for the simultaneous determination of the 15 PGRs in bean sprout.

Phenotypic, Stress Tolerance and Plant Growth Promoting Characteristics of Rhizobial Isolates from Selected Wild Legumes of Semiarid Region, Tirupati, India

Rhizobia are vital for nitrogen input, fertility of soil and legume plant growth. Knowledge on rhizobial diversity from arid and semiarid areas is important for dry land agriculture in the context of climatic change and for economic utilization. This study provides morphological, biochemical, stress tolerance and plant growth promoting characteristics of fifteen rhizobial isolates from the nodules of same number of wild legumes and one isolate from cultivated Arachis hypogea from semi-arid region, Tirupati. The bacterial isolates were confirmed as rhizobia based on colony morphology and biochemical tests. Based on the colour change of YMA-BTB medium, eight isolates were identified as slow growers and six were fast growers. The isolates differed in growth pattern, colony morphology, antibiotic resistance at higher concentrations and uniformity in utilization of carbon and nitrogen sources. The isolates are tolerant to NaCl up to one percent, displayed normal growth at temperatures 28℃ - 30℃, at neutral pH and poor growth at pH 5and 9. The isolates varied in the production of EPS and IAA, positive for phosphate solubilization and siderophore formation. This functional diversity displayed by the isolates can be utilised for the legume crop production by cross inoculation.

Evaluation of Plant Growth Promoting Ability of Bacillus amyloliquefaciens Bc2 and Trichoderma harzianum TR In Vivo

Bacillus amyloliquefaciens Bc2 and Trichderma harzianum TR were used to evaluate their growth-promoting activity on cultivated strawberries, under laboratory and field conditions, and we have noticed that the percentage of achene germination is important for ones treated with TR (=97%) followed by those treated with Bc2 strain (=90%) and the control (=84%). Inoculations on field showed that on untreated soil with insecticide, TR is effective and allows the development of plants and extends the duration of flowering and fruiting. On treated soil, Bc2 clearly promotes the growth and development of strawberry seedlings and its role as plant growth promoting microorganisms has been proved.

Influencing in vitro clonal propagation of Chonemorpha fragrans(moon) Alston by culture media strength,plant growth regulators,carbon source and photo periodic incubation

Chonemorpha fragrans is an endangered medicinal woody climber,regarded among alternative plant sources of camptothecin.Camptothecin is a monoterpene indole anti-cancer alkaloid with annual trade value of over three billion U.S.dollars in the recent,and is used in the production of its analog drugs approved for the chemotherapy of cancer of varied types.Effects of plant growth regulators,culture media strength and photoperi-odic duration on the micropropagation ef ciency of C.fragrans from nodal segment explants were studied on Murashige and Skoog(MS)medium amended with Thidiazuron(TDZ),Benzylaminopurine(BAP)or Kinetin(Kin).Thidiazuron was more ef cient over BAP and Kin when half basal MS medium was used over full or quarter strength.Results of carbon source experiment showed sucrose as the most effective over glucose,fructose,and maltose in the clonal production.Studies on the photope-riodic incubation duration showed 12 h as the best light period and sub or supra-optimal resulted in the production of abnormal and albino micro shoots.Experimental results on the evaluation of physiological,biochemical parameters showed the role of pigment molecules and antioxidant systems in the production of albino micro shoots.

Climate Change and Its Adverse Impacts on Plant Growth in South Asia:Current Status and Upcoming Challenges

Socioeconomic development,adaptive capacity of the population,and demographic conditions across the states of South Asia make it more vulnerable to climate change.South Asia is daily going to be more vulnerable to climate change and climatic variability.This region is facing multiple challenges in terms of climate change,dilapidation of ecosystems,and food insecurity.Climate is the primary determining factor for agricultural output,which unswervingly influences food production across the globe.South Asia is mainly an agricultural foundation based region and thus the economy of these regions directly depends on agriculture and agricultural production.Due to the extensive dependence on natural assets for thriving,it makes the people of this region more vulnerable to climate change.This region is now under serious risk from sea-level rising and growing incidences of extreme events such as flash floods,enhanced temperature,drought,salinity,cyclones,storms,landslides,and irregularity of precipitation.These abiotic stresses continuously disturb plant growth and productivity.It is now the time to take urgent action on these issues towards a sustainable,inclusive and resource efficient way to overcome this.In this review,we summarize the overall situation of climate change in the South Asian countries and their adverse consequences on plants,and upcoming challenges towards a sustainable production.

Effects of Three Plant Growth Regulators on Yield and Quality of Sunflower

Using Xinshikui No. 5 as the experimental material, the effects of different concentrations of mepiquat chloride （100, 200, 300,400, 500 mg/L）, chlormequat chloride （800, 1200,1 600, 2 000, 2 400 rag/L） and paclobutracol （50, 75, 100, 125, 150 mg/L） on yield and quality of sunflower were investigated. The results showed that plant growth regulators could improve the yield and quality of sunflower seeds to varying degrees. Specifically, 400 mg/L mepiquat chloride （ D4 ）, 800 mg/L chlormequat chloride （ Cl ） and 75 mg/L paelobutracol （ P2 ） significantly improved disk diameter, seed weight per disc, 100-sced weight, seed kernel rate and yield of sunflower; 400 mg/L mepiquat chloride （ D4 ）, 1 200 mg/L chlormequat chloride （ C2 ） and 75 mg/L paclobutracol （ P2 ） improved crude protein content, crude fat content, length and width of sunflower seeds. Based on comprehensive consideration, paclobutraeol is the most appropriate plant growth regulator for improving the yield and quality of sunflower in Xinjiang, and the optimal application concentration is 75 mg/L.

Teaching Reform and Practice of Plant Growth Environment Course in the Context of Application Transformation Development

Through the personnel training program,revising the syllabus,optimizing teaching contents,reforming teaching methods,strengthening practical teaching links and reforming examination methods,this paper explored the teaching reform and practice of Plant Growth Environment Course,in order to improve the teaching effect,stimulate learning interests of students,and cultivate application type talents meeting social demands.

The Effect of Nitrogen and Phosphorus Ratios and Electrical Conductivity on Plant Growth

Environmental concerns surround the use of plant growth retardants (PGRs) for plant height control, and non-chemical alternatives to PGRs can be labor intensive and expensive. Macronutrient modification is a little-studied, yet potentially effective method of controlling plant height. A number of studies have suggested that phosphorus (P) limitation may restrict plant height. Anecdotal evidence also suggests that using nitrate (NO3-), rather than ammonium (NH4+), as the principal nitrogen (N) source may help control plant height. The primary objective of this study was to evaluate different ratios of NO3-/ NH4+, NO3-/P and NH4+/P as well as electrical conductivity (EC) on plant height and growth. This was tested in a hydroponic system using marigolds, sunflowers and tomatoes. Initially, different ratios were tested at an EC of 1.2 dS·m-1, followed by using the same ratios at four ECs (0.6, 1.2, 2.2 and 4.0 dS·m-1) as a second objective. Although ratios did, at times, limit plant height, responses were season and species dependent, suggesting that modifications in plant nutrition, at the ratios used in this study, may not effectively control plant height in hydroponic systems. More consistent, yet species specific, height control was achieved by increasing EC level.