Effects of Tianda 2116 Plant Growth Regulator on Growth and Yield of Winter Wheat (Triticum aestivum L.)

To achieve optimum yield of wheat, supplementation of soil and foliar applied fertilizers with plant growth regulators is vital to assure effective assimilation of nutrients by plants. A trial was conducted at Gwebi Agricultural College Farm in Mashonaland West Province of Zimbabwe, during the 2012 winter wheat season (May to August), to evaluate the effects of differing times of application of Tianda 2116 plant growth regulator on the growth and yield of wheat (variety SC Sekuru). The trial was laid out in a Randomized Complete Block Design with three replications. The treatments were: Tianda 2116 applied at the following weeks after planting (WAP): 2 WAP, 3 WAP, 4 WAP, 5 WAP, 6 WAP, 14 WAP and no Tianda 2116 applied (control). No significant differences (P > 0.05) were noted among treatments for mean number of tillers per plant and mean number of spikes per plant. Application of Tianda 2116 at 2 and 3 WAP delayed flowering and physiological maturity. Early application of Tianda 2116 increased the number of spikelets per spike, thousand grain weight and grain yield. Conclusively, Tianda 2116 applied 2 or 3 WAP is effective in reducing growth while enhancing yield parameters in wheat production.

Effect of Cold Plasma Treatment on Seed Germination and Growth of Wheat

This study investigated the effect of cold helium plasma treatment on seed germina- tion, growth and yield of wheat. The effects of different power of cold plasma on the germination of treated wheat seeds were studied. We found that the treatment of 80 W could significantly improve seed germination potential （6.0%） and germination rate （6.7%） compared to the control group. Field experiments were carried out for wheat seeds treated with 80 W cold plasma. Com- pared with the control, plant height （20.3%）, root length （9.0%） and fresh weight （21.8%） were improved significantly at seedling stage. At booting stage, plant height, root length, fresh weight, stem diameter, leaf area and leaf thickness of the treated plant were respectively increased by 21.8%, 11.0%, 7.0%, 9.0%, 13.0% and 25.5%. At the same time, the chlorophyll content （9.8%）, nitrogen （10.0%） and moisture content （10.0%） were higher than those of the control, indicating that cold plasma treatment could promote the growth of wheat. The yield of treated wheat was 7.55 t-ha-1, 5.89% more than that of the control. Therefore, our results show that cold plasma has important application prospects for increasing wheat yield.

TaMIR1119, a miRNA family member of wheat(Triticum aestivum),is essential in the regulation of plant drought tolerance

Through regulating target genes via the mechanisms of posttranscriptional cleavage or translational repression, plant miRNAs involve diverse biological processes associating with plant growth, development, and abiotic stress responses, in this study, we functionally characterized TaMIR1119, a miRNA family member of wheat （Triticum aestivum）, in regulating the drought adaptive response of plants. TaMIR1119 putatively targets six genes categorized into the functional classes of transcriptional regulation, RNA and biochemical metabolism, trafficking, and oxidative stress defense. Upon simulated drought stress, the TaMIR1119 transcripts abundance in roots was drastically altered, showing to be upregulated gradually within a 48-h drought regime andthat the drought-induced transcripts were gradually restored along with a 48-h recovery treatment. In contrast, most miRNA target genes displayed reverse expression patterns to TaMIR1119, exhibiting a downregulated expression pattern upon drought and whose reduced transcripts were re-elevated along with a normal recovery treatment. These expression analysis results indicated that TaMIR1119 responds to drought and regulates the target genes mainly through a cleavage mechanism. Under drought stress, the tobacco lines with TaMIR1119 overexpression behaved improved phenotypes,, showing increased plant biomass, photosynthetic parameters, osmolyte accumulation, and enhanced antioxidant enzyme （AE） activities relative to wild type. Three AE genes, NtFeSOD, NtCAT1;3, and NtSOD2,1, encoding superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） proteins, respectively, showed upregulated expression in TaMIR1119 overexpression lines, suggesting that they are involved in the regulation of AE activities and contribution to the improved cellular reactive oxygen species （ROS） homeostasis in drought-challenged transgenic lines. Our results indicate that TaMIR1119 plays critical roles in regulating plant drought tolerance through transcriptionally regulating the target genes that modulate osmolyte accumulation, photosynthetic function, and improve cellular ROS homeostasis of plants.

Gibberellic Acid Promotes Early Growth of Winter Wheat and Rye

Winter wheat (Triticum aestivum) planting in Nebraska is recommended for mid Sep but summer crops are often harvested around Oct 1. Also, weather may delay planting. Could gibberellic acid (GA3), a growth stimulant, overcome the delayed seedling growth from late planting? Irrigated field trials were planted from 2005 to 2010 applying GA3 to wheat seed of cvs. Goodstreak and Wesley. In 2005, dip, spray and furrow GA3 applications to seed were tested. Dip and spray gave similar results. Furrow application was calculated too costly. Further tests used seed dips. In 2006 to 2008 planting, wheat was planted about 15 Sep, 1 Oct and 15 Oct. Trials planted in 2007 and 2008 included winter rye (Secale cereale) cv. Rymin. Heights in mid Nov showed a reduction with later planting. When planted about 1 Oct and 15 Oct, the delayed growth of Goodstreak, compared to planting two weeks earlier, was fully overcome by GA3 at 250 ppm. For Wesley, 1000 ppm GA3 was needed to nearly overcome later planting. Rymin rye gave an intermediate response between the two wheat cultivars. Spring and summer heights were not affected by GA3. Spring biomass, yield and harvested seed germination showed no GA3 effect. In later trials (planted in 2009 and 2010), the cytokinin 6-benzyl adenine (6BA) was added to GA3 to stimulate tiller formation. In the 1st year, 6BA at 2000 ppm depressed height, weight and yield without tiller promotion. Repeating the trial with lower rates (31 - 125 ppm 6BA) did not offer an additional advantage to GA3. The results indicate that seed application of GA3 can overcome delayed growth resulting from delayed planting of winter wheat and rye under irrigation.

Role,residues and microbial degradation of plant growth regulators(PGRs):A scoping review

Plant growth regulators(PGRs)play an important role in increasing crop yield,and quality,and enhancing crop stress resistance in agricultural production,especially for important crops.PGRs can affect the transport and distribution of assimilates by changing the content and distribution of endogenous hormones in plants.Numerous empirical research results have proven that PGRs have an important impact on the growth,development,and yield composition of wheat.Taking wheat plants as an example,this study reviews the application of PGRs in wheat production and explores their impact on wheat growth and yield.Furthermore,residues and microbial degradation of PGRs are summarized in detail.Finally,future research directions on PGR application in wheat production are proposed.This summary is of great significance for understanding the role of PGRs in wheat production.

Research progress on the synthesis of phenylurea derived plant growth regulators

Plant growth regulators(PGRs)are chemical substances that imitate the functions of phytohormones to enhance the crop yield and the harvest process.Phenylurea-derived plant growth regulators are known for their excellent efficacy in promoting fruit growth,particularly in kiwifruit,grapes,and melons.Phenylurea derivatives represent one class of the highly efficient and versatile PGRs.Specifically,forchlorfenuron(CPPU,N-(2-chloro-4-pyridinyl)-N0-phenylurea)exhibits similar growth-regulating efficacy to cytokinins and has a significant impact on the plant growth and the crop yield.As a result,there is growing interest in exploring the incorporation of various phenylurea moieties into agrochemicals to enhance their regulatory properties on crops.This review aims to provide a comprehensive overview on representative synthetic approaches for phenylurea derived PGRs.Additionally,we provide our perspective on the future development in this active researchfield.

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.

Exploration and development of artificially synthesized plant growth regulators

Plant growth regulators(PGRs)are a critical regulatory factor that influences plant development and against abiotic or biotic stress.The chemical synthesis of phytohormone analogues represents an effective approach for developing novel PGRs with enhanced bioactivity,reduced costs,and simplified synthesis.This review provides a comprehensive examination of artificially synthesized PGRs(phytohormone structural analogues and functional analogues)over the past five years,emphasizing the synthesis strategy,bioactivity,structure-activity relationships,and target protein.This review argues that the synthesis of functional analogues of phytohormones represents a crucial in the advancement of novel PGRs,and optimization of synthetic procedures would greatly facilitate the commercialization of these PGRs.

Bioassay of Winter Wheat for Gibberellic Acid Sensitivity

Increasing winter wheat seedling growth would make it a better winter cover crop. Gibberellic acid (GA3) seed treatment may accomplish this by stimulating stem growth. A bioassay, mimicking field conditions, could determine the relative sensitivity of conventional and semi-dwarf cultivars. In growth chambers set for cool (10℃/4℃) and warm (21℃/4℃) conditions, wheat seeds were treated with 0 and 125 to 16,000 ppm GA3. The cultivars Goodstreak (tall or conventional) and Wesley (semi-dwarf) were compared as standards. Emergence and plant height were measured. “Goodstreak” showed a significant growth promotion at 500 ppm GA3 when seeds were dipped and 2000 ppm when GA3 was applied in-furrow under both temperature regimes. “Wesley” in general required the same or a higher dose of GA3. Separately, the seeds of nine other cultivars were treated with GA3 as the standards. Based on maximum height promotion, the most sensitive cultivars under cool conditions were Goodstreak, Harry, Millenium, and Wahoo;under warm conditions, the most sensitive cultivars were Alliance, Goodstreak, Jagalene, and Millenium. In general, the least GA3 sensitive cultivars were Arrowsmith, Scout66, and Wesley. “Buckskin” and “InfinityCL” were intermediate. The rye cultivar Rymin also was tested and showed less sensitivity to GA3 than “Goodstreak”. When 6 benzyladenine (6BA) with GA3 was applied to “Goodstreak” and “Wesley” seed, emergence, plant height and weight, and tiller formation were reduced. Wheat cultivars will respond to GA3 and differ in the amount of GA3 needed. The results of this growth chamber study will guide subsequent field trials.

Assessment of biological changes in wheat seedlings induced by ^(12)C^(6+)-ion irradiation

The present study was designed to evaluate the effect of 12 6+ C ion beam (10～80 Gy) on biological changes of wheat seedlings. Reactive oxygen species (ROS)-related biomarkers and the quantification of plant survival and growth were examined at 10 day after carbon ions irradiation (LET: 30.8 keV/μm). The results showed that heavy ions obviously enhanced ROSs reflected by the production of O2 and H2O2 as well as TBARS, and - treatment with 20 Gy achieved the peak value, suggesting that higher mutagenic potential may occur at 20 Gy. Simultaneously, increase of SOD activity was induced by heavy ions to counteract ROS accumulation. On the other hand, higher doses at 40 and 80 Gy inhibited wheat growth and survival in comparison with the control, and reversely lower doses at 10 or 20 Gy stimulated wheat growth and survival. In conclusion, the above observations imply that a dose range of 20~40 Gy is likely promised for wheat mutation breeding.

Impacts of Climate Change on Growth Period and Planting Boundaries of Spring Wheat in China under RCP4.5 Scenario

This article contributes to research on how climate change will impact crops in China by moving from ex-post empirical analysis to forecasting. We construct a multiple regression model, using agricultural observations and meteorological simulations by GCMs, to simulate the possible planting boundaries and suitable planting re- gions of spring wheat under RCP4.5 scenario for the base period 2040s and 2070s. We find that the south bound- ary of possible planting region for spring wheat spreads along the belt： south Shandong-north Jiangsu-north Anhui-central Henan-north Hubei-southeast Sichuan-north Yunnan provinces, and will likely move northward under RCP4.5 scenario in 2040s and 2070s, resulting in the decrease of possible planting area in China. Moreover, the sowing and harvest date of spring wheat in the base period shows a gradually delayed phenomenon from the belt： south Xinjiang - Gansu, to the Tibet Plateau. As a result, the growth period of spring wheat in China will shorten because of the impacts of climate change. These results imply that a variety of adaptations measures should be set up in response to changing climatic conditions, including developing the planting base for spring wheat, restricting the planting area of spring wheat in sub-suitable areas at risk while expanding the planting area of optimal crops.

Effects of Trinexapac-Ethyl on different wheat varieties under desert conditions of Mexico

A field study was conducted to determine the effect of Trinexapac-Ethyl (TE) on four wheat varieties (Rafi C97, Altar C84, Nacori C97 and Rayon F86) at three growth stages (first node, second node and flag leaf). TE application (150 g a.i. ha-1) reduced plant height and decreased grain yield at any growth stage. Yield decrease was associated to a significant reduction in the number of grains per spike and in grain weight. TE delayed flowering time and grain maturity, while stem diameter and spikes m-2 were not affected. Further studies are needed to clarify the effect of TE on wheat under desert conditions of Mexico.

Influence of Plant Growth Regulators on Pollen Germination and Growth of Xinjiang Apricots

[Objective] This study aimed to investigate the influence of different plant growth regulators on apricot pollen germination and pollen tube growth. [Method] Pollens of six kinds of Xinjiang apricots were cultured in solid media supplemented with five plant growth regulators （GA3 , NAA, 2, 4-D, 6-BA, IAA）. Then the rate of pollen germination and the length of pollen tube were respectively measured. [Result] In a certain concentration range, GA3 most significantly promoted the pollen germination and the pollen tube growth of Shushanggan, Kalayulvke, Dayoujia, Yiliakeyulvke and Kabakehuanna; NNA had the strongest improvement function on Kumaiti’s pollen germination and pollen tube growth. [Conclusion] All the five plant growth regulators promoted the pollen germination and the pollen tube growth of apricots at low concentration but inhibited them at high concentration.

Effects of Plant Growth Regulator on Absorption,Circulation and Contents of Potassium in Flue-cured Tobacco

[Objective] This study was to investigate the effects of plant growth regulator on accumulation and circulation of potassium in flue-cured tobacco.[Methods] Hydroponics experiment was adopted to study the effects of plant growth regulator（NAA,GA3,BR） on accumulation and circulation of potassium in flue-cured tobacco.[Results] The BR treatment increased the absorption of potassium,calcium and magnesium in flue-cured tobacco,reduced the potassium emission from the root,enhanced the accumulation and contents and promoted the circulation of potassium in the tobacco plants.There was no statistical difference between the NAA and GA3 treatment.And BR treatment was 0.52%,0.30%,0.28% higher than NAA treatment in enhancing potassium content in tobacco plants at 2,7,12 d after topping.In a word,the results showed that BR treatment was the most.[Conclusion] BR treatment could effectively enhance potassium content in tobacco plants after topping.

Dwarfing effects of plant growth regulators on narcissi

The effects of four kinds of plant growth regulators with different concentrations on narcissi were studied in 2001. The results showed that the regulators could inhibit the growths of height and leaves of narcissi. Of the four regulators, the dwarfing effects of paclobatrazol (PP333) and uniconazole (S3307) on narcissi were better than those of chlorocholine (CCC) and dimethyl amino-sussinamic acid (B9). All of the regulators did not have significant effect on the root length. Moreover, the time of flowering was later for the narcissi treated with regulators than that of the control to a certain extent, and the range delayed was from 2 days to 19 days. The correlation analysis results showed that there was a significant correlation between the time of flowering and the concentrations of regulators. The ornament value of narcissi was obviously improved by using the regulators.

Influences of Carbon Sources and Plant Growth Regulators on Anther Culture Efficiency of Pepper

[Objective]In order to increase anther culture efficiency of pepper.[Method]MS culture media and Bolajiaohong were used in this experiment to study the influences of carbon sources and concentrations on anther callus induction of pepper.Jiayu was taken as a material to study influences of plant growth regulators and concentrations on anther callus induction of pepper according to L16（4^5） orthogonal design.[Result]The average callus and embryoid induction rates of maltose at all concentrations were higher than these of sucrose but the difference was not significant.Taking maltose or sucrose as a carbon source,3% to 6% concentration was good for increasing induction frequencies of calli and embryoids.However,If the concentration was over 6%,the induction rates were declined dramatically with the increase of sugar concentration.The influences of growth regulators on induction rate of calli were listed as 2,4-D﹥ZT﹥NAA﹥KT﹥6-BA;the influences on induction rates of embryoids were listed as 2,4-D﹥NAA﹥ZT﹥KT﹥6-BA.The 2,4-D,ZT,NAA and KT had signficant or extremely significant influences on induction rates of calli and embryoids.2,4-D,ZT at 1.0 mg/L and NNA,KT at 0.5 mg/L had the best effects.The influences of ZT on calli and embryoids were better than those of KT and 6-BA.1.0 mg/L 2,4-D ＋1.0 mg/L ZT ＋0.5 mg/L KT ＋0.5 mg/L 6-BA was the best regulator combination for induction culture of Jiayu anther.[Conclusion]The experiment provided research basis for anther culture of pepper.

Genome-editing of a circadian clock gene TaPRR95 facilitates wheat peduncle growth and heading date

Plant height and heading date are important agronomic traits in wheat(Triticum aestivum L.)that affect final grain yield.In wheat,knowledge of pseudo-response regulator(PRR)genes on agronomic traits is limited.Here,we identify a wheat TaPRR95 gene by genome-wide association studies to be associated with plant height.Triple allele mutant plants produced by CRISPR/Cas9 show increased plant height,particularly the peduncle,with an earlier heading date.The longer peduncle is mainly caused by the increased cell elon-gation at its upper section,whilst the early heading date is accompanied by elevated expression of flow-ering genes,such as TaFT and TacO1.A peduncle-specific transcriptome analysis reveals up-regulated photosynthesis genes and down-regulated IAAVAux genes for auxin signaling inpr95abad plants that may act as a regulatory mechanism to promote robust plant growth.A haplotype analysis identifies a TaPRR95-B haplotype(Hap2)to be closely associated with reduced plant height and increased thousand-grain weight.Moreover,the Hap2 frequency is higher in cultivars than that in landraces,suggesting the artifi-cial selection on the allele during wheat breeding.These findings suggest that TaPRR95 is a regulator for plant height and heading date,thereby providing an important target for wheat yield improvement.

Effect of vernalization and plant growth regulators on flowering of Onithogalum ‘Chesapeake Snowflake’

The effect of vernalization and two growth regulators Fascination^TM and Pro-Gibb^R on the growth, inflorescence development and flowering of Omithogalurrt Chesapeake Snowflake＇ was studied. Regardless of growth regulator treatment, chilling bulbs for 3 weeks at 10℃ before planting accelerated flowering of the first inflorescence by 5 to 6 days, elongated floral stem length by 1.5 to 2 cm and shortened leaf length by 4 to 5 cm as compared with non-chilled bulbs. When bulbs were chilled 3 weeks at 10℃ before planting, Fascination 2% and Pro-Gibb accelerated flowering of the first inflorescence by 2 to 6 days respectively as compared with the control. When bulbs were not chilled before planting, Fascination 2% and Pro-Gibb accelerated flowering of the first inflorescence by 6 to12 days respectively as compared with the control. The lengths of the leaves and the inflorescences were not affected by PGR treatment. Higher rates of Pro-Gibb （100 mg.L^-1 and 200 mg.L^-1） and more amount of Fascination 2%（100 μL and 200 μL） can cause abortion of inflorescence.

Effects of Plant Growth Regulators on the Contents of Reducing Sugar and Starch in Potato(Solanum tuberosum L.)

[Objective] The aim was to investigate the effects of plant growth regulators on contents of reducing sugar and starch in potato（Solanum tuberosum L.）.[Method]A potato cultivar named ＇Holand-212＇ with three treatments by spraying Diethyl aminoethyl hexanoate（DTA-6）,Uniconazole（S3307）and SOD mimics（SODM）were employed to compare differences of the contents of reducing sugar and starch in potato leaves,stolons and tubers in a field experiment.[Result]DTA-6 treatment could significantly reduce the contents of starch and reducing sugar in potato stolons in the period of 100-110 d after seeding,and it could also reduce the content of reducing sugar in tubers,but there is an opposite result in leaves in the same period,significantly.S3307 could extremely significantly increase the content of starch,and can promote the transfer of starch in stolons,in addition,it also could reduce the content of reducing sugar in tubers,and extremely significantly increase the content of starch in leaves at the 110 d after sowing.Moreover,there is a similar effect between SODM and S3307.[Conclusion]The research results are significant for understanding mechanisms of plant growth regulators and promoting application of plant growth regulator in potato.

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.