Response of winter barley cultivars to nitrogen and a plant growth regulator in relation to lodging

1991 ◽  
Vol 116 (2) ◽  
pp. 191-200 ◽  
Author(s):  
E. M. White

SUMMARYApplications of nitrogen and a plant growth regulator (mepiquat chloride and ethephon) were used to manipulate stem structure and induce differing degrees of damage due to leaning and lodging in six cultivars of winter barley grown in Belfast, UK, in 1986/87. Weighted incidences of leaning and lodging were combined to give an index indicating damage susceptibility of the cultivars. The index was very high (70) in Pipkin and ranged between 1 and 18 in the other cultivars. Differences between cultivars in number of internodes, plant height and stem weight did not explain their differences in resistance to damage. However, dry weight per unit length ranged from 2·35 and 2·34 mg/mm in the strongest cultivars, Panda and Jennifer, respectively, to 1·75 mg/mm in the weakest cultivar, Pipkin.Nitrogen application increased plant height but did not affect dry weight/main stem, so that dry weight/unit length of stem decreased. The growth regulator treatments reduced plant height and although dry weight/stem did not decrease significantly, dry weight/unit length of stem was similar in treated and untreated plots.Dry weight/unit length has potential as an objective indicator of straw strength in winter barley cultivars and could be used in cultivar evaluation in the absence of damage in field trials.

1997 ◽  
Vol 128 (2) ◽  
pp. 143-154 ◽  
Author(s):  
M. A. FROMENT ◽  
H. G. McDONALD

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.


2016 ◽  
Vol 2 (2) ◽  
pp. 104
Author(s):  
Tyas Larasati ◽  
Suci Rahayu ◽  
Fauziyah Harahap

The objectives of this research were to composed organ from callus culture and to found the best concentration of plant growth regulator for organ growth from female flower explant of oil palm. This research has already done from June 2014 to May 2015 at Laboratory of Plant Physiology and Tissue Culture Department of Biology Faculty of Mathematics and Science University of North Sumatera. This research used Nonfactorial Completely Random Design. Explant was treated with five concentrations of 2,4-Dichlorophenoxy acetic acid (2,4-D; 99, 110, 120, 132, and 140 mg/L) for callus induction on Y3 medium (Eeuwens 1976). The result of this research showed that organ was formed from this treatment (basal segment of female flower explant) was root organ. 2,4-D plant growth regulator positively affected to growing of the root. The best result for time of callus induction, time of root growth, the highest percentage of explants that formed the root, fresh weight and dry weight of callus that has become the root generation was resulted from 99 mg/L 2,4-D.   Key words: Elaeis guineensis Jacq., female flower, plant growth regulator 2,4-D, organogenesis


1996 ◽  
Vol 10 (4) ◽  
pp. 851-855
Author(s):  
C. Dale Monks ◽  
Michael G. Patterson ◽  
Malcolm Pegues

Field experiments were conducted in Alabama from 1992 through 1994 to evaluate the potential of the methyl ester of bensulfuron applied at sublethal rates as a plant growth regulator for reducing plant height and boll rot in cotton. Bensulfuron at 0.017 and 0.034 g ai/ha or mepiquat chloride at 10 g ai/ha was applied POST alone at the pinhead square or early-bloom stage of cotton growth or sequentially at 0.017 followed by (fb) 0.017 g/ha, 0.034 fb 0.034 g/ha of bensulfuron and 5 fb 5, 10 fb 10, 10 fb 20, or 20 fb 20 g/ha of mepiquat chloride. Mepiquat chloride had no effect on yield in 1992 and 1994 but decreased yield when applied sequentially in 1993. Bensulfuron was generally detrimental to first position fruit retention, and it delayed maturity. Treatments that reduced plant height did not reduce boll rot. Bensulfuron treatments that reduced plant height also reduced yield; therefore, the potential for its use as a growth regulator in cotton appears limited.


2020 ◽  
Vol 100 (6) ◽  
pp. 653-665
Author(s):  
B.D. Tidemann ◽  
J.T. O’Donovan ◽  
M. Izydorczyk ◽  
T.K. Turkington ◽  
L. Oatway ◽  
...  

Malting barley is important in western Canada, yet many malting cultivars do not meet malt quality standards, in part due to lodging. Lodging can decrease barley yield and quality thereby reducing the acceptability for malting. In other countries, plant growth regulator (PGR) applications are used to mitigate lodging. Chlormequat chloride (chlormequat), trinexapac-ethyl (trinexapac), and ethephon were tested at five locations over 3 yr in western Canada for their ability to limit lodging, as well as their effects on yield, agronomic traits, and pre-malt quality characteristics. PGR applications occurred between Zadoks growth stage (GS) 30–33 for chlormequat and trinexapac and GS 37–49 for ethephon. Seeding rates of 200, 300, and 400 seeds m−2 of CDC Copeland barley were used to increase the likelihood of lodging. Increased seeding rate decreased tillers per plant, height, days to maturity, kernel protein, and kernel weight. Ethephon increased the number of tillers per plant and decreased plant height, kernel plumpness, and kernel weight. Trinexapac decreased plant height and kernel weight. Days to maturity was investigated across site-years, with ethephon increasing maturity in 60% of comparisons. Trinexapac and chlormequat had limited effects on maturity. Lodging was investigated across site-years, with trinexapac showing the largest number of lodging reductions and scale of reductions. Ethephon reduced lodging in 36% of comparisons, while chlormequat had inconsistent effects. None of the products affected yield or grain protein. The results suggest PGRs may not be the solution to lodging for CDC Copeland barley on the Canadian Prairies; however, trinexapac shows the most promise of the products tested.


1992 ◽  
Vol 72 (4) ◽  
pp. 1153-1156 ◽  
Author(s):  
K. J. Kirkland

A 3-yr field experiment was conducted at the Scott Experimental Farm to determine the effect of the growth regulator, triapenthenol, on the growth and development of Argentine canola (Brassica napus L.). Triapenthenol reduced plant height 25–45 cm under optimal growing conditions. Increases in yield, branches and total pods were observed. Application at the bud stage was more effective than earlier treatment in the rosette. It was concluded that triapenthenol application to canola could be a useful management tool, particularly under optimal growing conditions.Key words: Canola, growth regulator, RSW-0411, lodging


2021 ◽  
Vol 39 (2) ◽  
pp. 62-67
Author(s):  
Sean J. Markovic ◽  
James E. Klett

Abstract Moroccan pincushion (Pterocephalus depressus) is a drought-tolerant perennial that is being used in landscapes throughout arid areas of the western United States. This paper describes two experiments researching vegetative cutting production from stock plants. Moroccan pincushion stock plants received foliar applications of gibberellic acid (GA3), benzyladenine, ethephon, or auxin [indole-3-butyric acid (IBA)] plant growth regulators (PGR). Plant growth regulators were applied singularly and in combination with GA3 to determine efficacy on stock plant growth. A propagation study was conducted simultaneously to determine effects of these different PGR treatments applied to stock plants on the rooting of moroccan pincushion cuttings. The stock plant study showed GA3 + benzyladenine application increased cutting production over other PGR treatments. Fresh weight of moroccan pincushion cuttings did not differ among treatments. While cuttings did not differ in dry weight in experiment 1, statistical differences were observed in experiment 2. However, these differences in dry weight did not affect the quality of the cuttings. Cuttings from stock plants treated with GA3 + IBA treatment had the highest numerical growth index [(height + width + width)/3]. Cuttings from stock plants treated with GA3 alone or in combination with another PGR were all greater in average growth index and statistically differed from those without GA3 being applied. PGR treatments did not affect rooting percentages of the cuttings with nontreated stock plant cuttings successfully rooting at an average rate of 95%. However, GA3 + IBA was the only treatment where cuttings had 100% rooting for both experiments, indicating potential rooting benefits. Index words: Plant growth regulator, propagation, Pterocephalus depressus, vegetative cuttings. Species used in this study: Moroccan pincushion [Pterocephalus depressus Archibald]. Chemicals used in this study: gibberellic acid (GA3), benzyladenine, ethephon, indole-3-butyric acid (IBA).


2018 ◽  
Vol 51 (4) ◽  
pp. 60-72
Author(s):  
E.K. Eifediyi ◽  
F.O. Ogedegbe ◽  
N.B. Izuogu ◽  
C.A. Adedokun ◽  
A. Katibi ◽  
...  

Abstract The Guinea savannah zone of Nigeria is beset by increasing population and infrastructural development, thereby putting pressure on available land with rapidly declining fertility due to low organic matter content, soil erosion, high temperature and seasonal bush burning. Sesame is cultivated in this zone and the yield has remained very low, compared to yield in other parts of the world. This could be attributed to poor nutrient status and poor cultural practices used by peasant farmers. A field experiment was conducted at the Teaching and Research Farm, University of Ilorin, Nigeria, in a southern Guinea savannah zone in 2015 and repeated in 2016 cropping season to determine the effects of 2,4-Dichlorophenoxyacetic acid (2,4-D), a plant growth regulator and NPK fertilizer on the growth and yield of sesame. The experiment was laid out as a factorial arrangement, fitted into a randomized complete block design replicated thrice. The factors imposed were 2,4-D (0, 5 and 10 ppm ha−1) and NPK 15:15:15 (0, 100, 200 and 300 kg ha−1). Data were collected on vegetative traits (plant height, number of leaves, leaf area) and yield components (number of capsules per plant; yield per plant and per hectare). The data were subjected to analysis of variance (ANOVA) using the Genstat statistical package 17th edition and significant means were separated by using the least significant difference at 5% level of probability. The result revealed that using plant growth regulator and NPK fertilizer had significant effects (p<0.05) on plant height (151 cm) and yield per hectare (530 kg/ha). The qualitative and quantitative analysis of the seeds further reaffirmed the presence of bioactive compounds, such as saponins, tannins, flavonoids and phenolic compounds, which are important health promoting food in the seeds.


2021 ◽  
pp. 1-11
Author(s):  
Jonathan Ebba ◽  
Ryan W. Dickson ◽  
Paul R. Fisher ◽  
Crysta N. Harris ◽  
Todd Guerdat ◽  
...  

The overall goal was to evaluate fertilizer options for greenhouse producers, with or without a plant growth regulator (PGR) application, to improve subsequent performance of container-grown annuals. Petunia (Petunia × hybrida) was the model container-grown crop in simulated production and consumer environments. The first experiment at two locations (New Hampshire and Florida) compared strategies using water-soluble fertilizer [WSF (17N–1.8P–14.1K)], controlled-release fertilizers (CRF), and slow-release fertilizers (SRF) that were either applied throughout or at the end of the 8-week production phase [point of shipping (POS)] for petunia rooted cuttings grown in 8-inch azalea containers. In the subsequent simulated “consumer” phase, container plants were irrigated with clear water (no fertilizer) for 6 weeks. Plant performance [number of flowers, SPAD chlorophyll index, dry weight, and tissue nitrogen (N)] at the end of the consumer phase was improved by top-dressing at POS with either CRF or granular organic fertilizer (both at 2.74 g/container N), or preplant incorporation of either a typical CRF at 4.12 g/container N or a CRF with an additional prill coating to delay initial release (DCT) at 2.74 g/container. There was no carry-over benefit from applying a liquid urea-chain product (1.37 or 2.74 g/container N) or top dressing with granular methylene di-urea (2.74 g/container N), or 400 mg·L–1 N (0.2 g/container N) from a liquid organic fertilizer at POS. The consumer benefit of applying 400 mg·L–1 N (0.2 g/container N) from a WSF at POS was increased by supplementing with 235 mg·L–1 magnesium (Mg) and 10 mg·L–1 iron (Fe). A second experiment in 10-inch-diameter pots evaluated the effect on consumer performance from providing 200 or 400 mg·L–1 N of WSF with the PGR paclobutrazol, at the final 1 L/pot irrigation at POS. Application of 3 mg·L–1 paclobutrazol delayed leaf yellowing and reduced plant height, width, and shoot dry weight during the consumer phase, resulting in a more compact growth habit and higher plant quality compared with plants that received no PGR, regardless of WSF treatment. Addition of supplemental 235 mg·L–1 Mg and 10 mg·L–1 Fe to the high rate of WSF and PGR did not improve consumer performance compared with other treatments that included a PGR. Overall, the first experiment demonstrated that the most effective fertilizer strategies require a CRF or SRF that will release nutrients throughout the consumer phase, and that impact of liquid fertilizer options is limited because of lower N supply per container. A single application at POS of a high rate of WSF with supplemental Mg and Fe may have short-term benefits, for example while plants are in a retail environment. Growers should consider combining a residual fertilizer with a PGR application for premium, value-added container annuals.


2000 ◽  
Vol 10 (1) ◽  
pp. 151-153 ◽  
Author(s):  
Brian E. Whipker ◽  
Shravan K. Dasoju ◽  
Michael R. Evans

Drench applications of paclobutrazol or uniconazole were applied at doses of 0, 0.0025, 0.005, 0.01, 0.02, or 0.04 mg a.i./pot (28,350 mg = 1.0 oz) to vegetatively propagated `Aurora', `Medallion Dark Red', and `Pink Satisfaction' geranium (Pelargonium ×hortorum L.H. Bailey). Geranium total plant height, leaf canopy height, and plant diameter responded similarly to drench applications of either paclobutrazol or uniconazole. There was a significant quadratic relationship between plant growth regulator (PGR) dose and total plant height and leaf canopy height for `Aurora' and `Medallion Dark Red', with total plant height and leaf canopy height being shorter as paclobutrazol or uniconazole doses increased up to 0.02 mg. However, doses of ≥0.02 mg had little additional effect on total plant height and leaf canopy height. Most of the total height control achieved by the use of PGRs was primarily due to a reduction of leaf canopy height, rather than inflorescence height. Doses of 0.005 to 0.01 mg of either PGR produced marketable sized potted plants of `Medallion Dark Red' and `Pink Satisfaction'. `Aurora', which was the most vigorous cultivar, required doses of 0.01 or 0.02 mg of either paclobutrazol or uniconazole to produce marketable sized potted plants.


2016 ◽  
Vol 26 (3) ◽  
pp. 320-326
Author(s):  
Christopher J. Currey ◽  
Kellie J. Walters ◽  
Kenneth G. McCabe

Our objective was to quantify the efficacy of different plant growth regulator (PGR) substrate drenches on growth of lantana (Lantana camara) cultivars varying in growth habit. Rooted ‘Little Lucky Peach Glow’, ‘Lucky Peach’, and ‘Landmark Peach Sunrise’ lantana cuttings were individually planted into 4-inch-diameter containers filled with a commercial, soilless growing substrate. Fourteen days after planting, solutions containing 0 (control), 0.5, 1, 2, or 4 mg·L−1 ancymidol, flurprimidol, paclobutrazol, or uniconazole were applied to the surface of the growing substrate. Six weeks after applying PGR drenches, data were collected. The growth index (GI), an integrated measurement of plant size incorporating the height and widths of plants, was calculated. There was variation in the GI among the control plants, reflecting variation among cultivars within the species. In addition, we measured variation in activity among the different PGRs applied. Across the concentrations applied, ancymidol generally had the lowest activity across the four PGRs. For example, drenches containing 4 mg·L−1 ancymidol resulted in plants that were similar to plants treated with 0.5 to 1 mg·L−1 flurprimidol or uniconazole or 2 mg·L−1 paclobutrazol for ‘Lucky Peach’ lantana. Across all cultivars, flurprimidol and uniconazole had the greatest activity in suppressing plant height, width, and GI. Substrate drenches containing flurprimidol, paclobutrazol, or uniconazole are useful to control size of lantana produced in containers, though the recommended concentration depends on the active ingredient and the growth habit of cultivars being treated.


Sign in / Sign up

Export Citation Format

Share Document