CCC Treatment Research Articles

Response of fruitset and other yield components to shoot topping and 2-chlorethyltrimethyl-ammonium chloride application

Background and Aims: We investigated the effectiveness of shoot topping and 2-chlorethyltrimethyl-ammonium chloride (CCC) application on the control of fruitset and other yield components on the grapevine varieties Cabernet Sauvignon, Chardonnay and Tempranillo at two sites over two or three seasons. Methods and Results: Treatments were applied before and during the flowering period. Fruitset and yield per vine increased in response to both shoot topping and CCC treatment, especially when shoot topping was applied between E–L stages 19 and 23, and when CCC was applied 1 week before flowering. All varieties at both locations responded to shoot topping to some degree: from 20 to 57% relative to the control for fruitset and from 16 to 97% for yield per vine. Conclusions: Fruitset, and, thus, yield, can be improved by cultural practices in all seasons, but the magnitude of the response may be greatest in those seasons when fruitset is lower than the average. Neither berry number per bunch nor the visual appearance of the bunches were reliable indicators of fruitset performance. Significance of the Study: Optimal timing of shoot topping and CCC application as cultural practices is critical to maximise the response. The ‘Coulure Index’ and the ‘Millerandage Index’, which are described for the first time, are novel and useful indicators of fruitset that have been developed to quantify the reproductive performance of grapevines.

Effect of phytohormones on growth and ion accumulation of wheat under salinity stress

A hydroponics experiment was conducted to assess the role of abscisic acid (ABA), benzyladenine (BA) and cycocel (CCC) on growth and ion accumulation of three spring wheat cultivars, cv. Wafaq-2001, cv. Inqulab-91, and cv. SAARC-1 under salinity stress. Seeds of all the cultivars were treated prior to sowing with ABA and BA each at 10-5 M and CCC at 10-6 M for 24 h. Three weeks old plants of both the cultivars were exposed to 0, 75 and 150 mM NaCl. Thirty day old plants were harvested after sixteen days of salt treatment. Dry weight of shoot and root were decreased with salt treatment. But ABA, BA and CCC treatments caused a significant ameliorative effect on all the cultivars. Concentrations of Na+ and Cl- in shoot of all the three cultivars were increased with the increasing level of NaCl. ABA, BA and CCC pre-treatment increased K+ and Ca2+ but reduced Na+ and Cl- concentrations in shoot of all the cultivars. However, the magnitude of reduction was higher in ABA pre-treated plants.

Effect of phytohormones on growth and ion accumulation of wheat under salinity stress

A hydroponics experiment was conducted to assess the role of abscisic acid (ABA), benzyladenine (BA) and cycocel (CCC) on growth and ion accumulation of three spring wheat cultivars, cv. Wafaq-2001, cv. Inqulab-91, and cv. SAARC-1 under salinity stress. Seeds of all the cultivars were treated prior to sowing with ABA and BA each at 10-5 M and CCC at 10-6 M for 24 h. Three weeks old plants of both the cultivars were exposed to 0, 75 and 150 mM NaCl. Thirty day old plants were harvested after sixteen days of salt treatment. Dry weight of shoot and root were decreased with salt treatment. But ABA, BA and CCC treatments caused a significant ameliorative effect on all the cultivars. Concentrations of Na+ and Cl- in shoot of all the three cultivars were increased with the increasing level of NaCl. ABA, BA and CCC pre-treatment increased K+ and Ca2+ but reduced Na+ and Cl- concentrations in shoot of all the cultivars. However, the magnitude of reduction was higher in ABA pre-treated plants.

감자절간 기내배양에서 소괴경의 형성과 형태적 발달

One-node stem pieces ca. 1 cm in length containing a axillary bud and a fully expanded leaf were obtained from it in vitro plants of potato (Solanum tuberosum L.). Leaves were removed and the nodes were cultured on the MS medium to investigate the effects of temperature, day length, sucrose, and CCC in microtuber formation and development. The fresh weight of microtubers after 80 days increased significantly at 8% sucrose and compared with . The tuberization and development were reduced at except short-day treatment of 8 hours at 8% sucrose. The fresh weight and diameter were increased on the culture medium added CCC 500 mg/L. The potato tuberization was promoted under short daylength, and it showed great effect by treatment with the CCC. Though the tuberization was promoted at low temperature of in a histologic change of an axillary bud part cell of a potato, the cells were able to observe the swelling growth. Swelling growth of tissue was stimulated in the darkness and was more remarkable by addition of CCC. In particular, in the visual ratio of cell division for each position in the tissue, the cortex part showed larger ratio of cell expansion than that of the pith part. The effect of CCC was identified at 8% sucrose in the darkness. The effect of CCC was not showed in sucrose 3% under long daylength of 16 hours. As a result, the fact of a substance with AGPase important for starch composition was certified by the result with the inclose of AGPase activity on high concentration of sucrose, CCC, and dark treatment by which tuber formation and development are promoted.

Effect of plant growth regulators and chemicals on morphological traits and yield of banana cv.Grand Nain

Foliar application of CCC 1000 ppm at 4th and 6th month after planting of banana cv. Grand Nain significantly increased the pseudostem girth, number of leaves, root volume and number of roots. However, the maximum leaf area and leaf area index were recorded in brassinolide treated plants. CCC treatment improved the number of hands, number of fingers, finger size and thereby bunch weight, yielding maximum fruit of 80.38 t ha-1. The quality parameters viz., total soluble solids, ascorbic acid, reducing sugars and total sugars were also influenced significantly. by foliar spray of CCC at 1000 ppm concentration.

Effects of growth retardant application on grape quality of « Mavrodafni » grapevine variety

<p style="text-align: justify;">The effects of bloom applications of 2-Chloroethyltrimethylammonium chloride (CCC) and Succinic acid-2,2-dimethylhydrazide (SADH) on fruit quality of Mavrodafni wine grape variety were studied. Over the vegetative period of 2000, sprays of 500 or 1 000 mg/l CCC and 3 000 or 6 000 mg/l SADH were applied, two weeks before bloom or at 20 p. cent of bloom in a completely randomized experimental design, replicated 10 times. Bunch and berry characteristics, berry composition, and phenolic maturity were measured at harvest. There were no differences between the two days of application. Berry number per bunch and per cm of rachis length, were increased by CCC 1 000 mg/l and SADH 6 000 mg/l treatments. Berry weight was decreased by all treatments with a greater reduction in CCC 1 000 mg/l treatment. Soluble solids were reduced by SADH treatment with a greater reduction in 6 000 mg/l of SADH and increased by CCC treatments at both concentrations. Anthocyanin concentration and extractability were increased in CCC at 1 000 mg/l treatments, while the extractability of grains tannins was reduced. A strong decrease of bud fertility was observed in 6 000 mg/l of SADH.</p>

Yield formation of spring rye at high latitudes with reference to seeding rate and plant growth regulation

Aspects of crop physiology and agronomy of spring rye were evaluated at Viikki Experimental Farm, University of Helsinki in 1996-1998 to get baseline information on its potential as a novel cereal crop in southern Finland.The German spring rye cultivar Ovid was fertilized with 80 kg N ha-1. Seeding rates were 300,500 and 700 viable seeds m-2. Chlormequat chloride (CCC)was sprayed at the two-node stage of the main shoot and its effects on lodging and yield formation were studied. Various traits were assessed that characterised tiller and main shoot growth and productivity, growth duration and plant stand structure.Spring rye responded differently over years and among CCC treatments. CCC increased grain yield by about 200 kg ha -1 compared with the control.Spring rye has long straw (130-140 cm)and tended to lodge under heavy rainfall.Thus,grain yield was maximum (ca. 5200 kg ha -1 in 1997)when rainfall was minimum.Partly because high seeding rates enhanced lodging,no seeding rate effects on grain yield were recorded.At 300 seeds m-2, yield formation of both main shoot and tillers was enhanced to compensate for the reduced number of main shoots m-2. Ripening was not delayed at low seeding rates.Grain and hectolitre weights were not affected by seeding rate. Thus,spring rye is a potential crop for Finland if low seeding rates are used.;

Chlormequat chloride and ethephon affect growth and yield formation of conventional, naked and dwarf oat

Department of Plant Production, PO Box 27, FIN-00014 University of Helsinki, Finland. Current address: MTT Agrifood Research Finland, Plant Production Research, FIN-31600 Jokioinen, Finland. e-mail: pirjo.peltonen-sainio@mtt.fi Plant growth regulators (PGRs) are not usually applied to oat (Avena sativa L.) crops. This study was designed to test whether the antigibberellin chlormequat chloride (CCC) and ethylene-releasing ethephon sprayed on to oat foliage represent potential agents for manipulation of yield formation under northern growing conditions. Effects of these PGRs on yield components and tiller growth and productivity were examined in detail. This study included a long-strawed landrace, a modern standard height cultivar, two naked (A. sativa ssp. nuda L.) and two dwarf oats. Field experiments were conducted at Viikki Experimental Farm, University of Helsinki, in 1995 and 1996. Chlormequat chloride was sprayed at the two-node stage and ethephon when the flag leaf ligule was just visible on the main shoot. Various traits characterizing growth and yield formation were assessed. Chlormequat chloride increased grain yield by 0% to 13% depending on cultivar and year, while ethephon most often decreased it by up to 17%. No lodging occurred and the recorded increase in grain yield of CCC treated plants was not therefore due to prevention of lodging. However, CCC treatment resulted in more panicles per square meter and in 1995 tillers contributed more to grain yield. Ethephon treated plants had less grains per main shoot panicle, lower panicle filling rate (PFR) and parallel decreased harvest index (HI). Stem elongation of dwarf oat was enhanced by CCC, in contrast to that of conventional and naked cultivars.;

PHYSIOLOGICAL AND BIOCHEMICAL EFFECTS OF MEPIQUAT CHLORIDE ON GROUNDNUT (Arachis hypogaea)

Experiments were carried out to understand the physiological effects of Mepiquat Chloride (MC), 1, 1-dimethyl piperidinium chloride on groundnut (Arachis hypogaea L.) at different concentrations and in comparison with CCC (2-chloro ethyl trimethyl ammonium chloride). Foliar application of MC at 125 ppm on 35 DAS showed substantial increase in the nitrogen (N) content accounting for 23 per cent over the unsprayed control and 12 per cent over the CCC treatment. Phosphorus (P) and Calcium (Ca) contents were also increased, while potassium (K) was unaffected by application of MC.

Possible Involvement of Altered Gibberellin Metabolism in the Induction of Tomato Irregular Ripening in Dwarf Cherry Tomato by Silverleaf Whitefly

External and internal tomato irregular ripening (TIR) symptoms were associated with the feeding of silverleaf whitefly (SLW), Bemisia argentifolii Bellows and Perring. Four experiments consisting of various soil drench applications of GA3 (100 ppm) and cycocel (CCC, an inhibitor of GA biosynthesis; 1,000 and 2,000 ppm) were applied to dwarf cherry tomato cv. Florida Petite in the presence and absence of SLW in an attempt to mimic the disorders induced by the SLW. The application of GA3 induced external and internal TIR symptoms similar to the SLW-induced disorder. Minimal TIR-like symptoms also occurred in the control and CCC treatments. Internal TIR symptoms in GA3, GA3 plus SLW, and GA3 plus CCC treatments ranged from 66% to 97% throughout the experiments. The incidence of external TIR symptoms was highest in the GA3 plus SLW treatment compared with the other treatments. CCC reduced the incidence of external TIR symptoms induced by GA3 or GA3 plus SLW treatments. However, CCC-treated plants also attracted more oviposition and higher populations of SLW and consequently induced a greater incidence of TIR symptoms than SLW treatment alone. Furthermore, although low SLW populations may be associated with low external TIR symptoms, internal TIR symptoms almost always remained high in infested plants. The results suggest that the TIR disorder in dwarf cherry tomato which is induced by the SLW may be a gibberellin-regulated disorder.

Plant Growth Regulators (GA3 and CCC) and Silverleaf Whitefly Effects on the Induction of Tomato Irregular Ripening in Dwarf Cherry Tomato

External and internal tomato irregular ripening (TIR) symptoms have been associated with the feeding of silverleaf whitefly (SLW), Bemisia argentifolii Bellows and Perring. Soil drench application of gibberellic acid (GA3) (100 ppm, Trial 1 and 2) and cycocel (CCC) (2000 ppm, Trial 1; 1000 ppm, Trial 2) were applied to dwarf cherry tomato (Lycopersicon esculentum) in the presence and absence of SLW to mimic the TIR disorder induced by the SLW. Application of GA3 induced external and internal TIR symptoms similar to the SLW-induced disorder in `Florida Petite'. There were essentially no TIR symptoms in fruit treated with CCC, an inhibitor of GA biosynthesis. In Trial 1, internal white tissue in GA3, SLW, and CCC treatments was expressed in 97%, 95%, and 4% of the total fruit, respectively. Incidence of external TIR symptom was highest (56%) in the GA3 plus SLW treatment. In Trial 2, GA3 application in the presence (83%) or absence (85%) of SLW resulted in the highest incidence of fruit with internal white tissue. External TIR symptoms induced by GA3 in the presence and absence of SLW were reduced with CCC application. These results suggest that the TIR disorder in tomato is induced by the SLW may be a GA3-regulated disorder.

Regulation of α-amylase isoenzyme expression in Araucaria araucana by gibberellic and abscisic acids

Expression of α-amylase (EC 3.2.1.1) isoenzymes present in the embryos and mega-gametophytes of Araucaria araucana seedlings was studied under gibberellic acid (GA 3) and abscisic acid (ABA) treatments and after 90 hr of imbibition in 20 mM of β-chloroethyltrimethylammonium (CCC), a GA 3 biosynthesis inhibitor. When CCC was used, α-amylase activity in the treated embryos decreased to 28% with respect to the controls. The isoenzymes of R m 0.42 and 0.51 were greatly affected. When the embryos were imbibed simultaneously in the presence of 20 mM CCC and 10 −5 M of GA 3, α-amylase activity and the expression of isoenzymes were restored with respect to controls. ABA at 10 −4 and 10 −5 M decreased α-amylase activity of embryos to 67 and 81%, respectively. Expression of isoenzymes of R m 0.51 was greatly decreased by ABA but the effect on the others was small. Isoenzyme expression of mega-gametophytic α-amylase was not affected by CCC, GA 3 or ABA treatment.

ASPECTOS MORFOANATÔMICOS DE FRUTOS DE TOMATEIRO CULTIVAR ÂNGELA GIGANTE, SUBMETIDOS A TRATAMENTOS COM REGULADORES VEGETAIS

O presente trabalho teve como finalidade obter dados morfológicos de frutos de tomateiro, Lycopersicon esculentum Mill. `Ângela Gigante', submetidos à ação de reguladores vegetais, em dois ensaios que ocorreram em épocas distintas, em casa de vegetação. As mudas foram selecionadas e transplantadas para vasos com capacidade de 12 L de terra, contendo uma mistura de solo argiloso, areia, matéria orgânica e uma adubação mineral complementar de N, P, K. No segundo ensaio, após o transplante das mudas, além da adubação mineral complementar de N, P, K, efetuaram-se adubações adicionais (fertirrigação). Em ambos os ensaios, quando as plantas atingiram quatro folhas definitivas, realizaram-se as pulverizações com giberelina, GA3 50 mg/L; ácido naftalenacético, NAA 100 mg/L; cloreto (2-cloroetil) trimetilamônio, CCC 1.500 mg/L e ácido succínico -2,2 dimetil-hidrazida, SADH 3.000 mg/L. Em relação aos estudos anatômicos, observou-se que os tratamentos com retardadores vegetais (CCC e SADH) produziram frutos firmes, com formato tipo barril e ombros salientes; entretanto, em seção transversal, notou-se perda de viscosidade e atrofia de sementes, principalmente nos frutos de plantas tratadas com SADH. Os tratamentos com NAA e GA3 causaram eventual formação de frutos geminados. O tratamento com GA3 apresentou o parênquima do pericarpo com grãos de amido em processo de fragmentação, provavelmente em virtude de o GA3 acelerar a atividade da amilase, afetando o processo de maturação dos frutos e transformando o amido em açúcares. Notaram-se no mesocarpo células com grande quantidade de cristais de oxalato de cálcio sob a forma de areia cristalina. Do tratamento com CCC resultaram frutos suculentos com células da placenta degeneradas, deixando livre grande quantidade de mucilagem. O pericarpo apresentou grande quantidade de grãos de amido composto em toda a extensão, provavelmente por haver um atraso no processo de maturação dos frutos.

Effects of Chlormequat Chloride Rate on Growth and Development of Several Aster Cultivars

Our purpose was to determine growth regulators rate effects on growth and development of aster Callistephus chinensis. During Spring 1993 and 1994, six aster cultivars were sown into 200-unit plug trays containing Pro-Mix PGX. Seedlings were transplanted into 10-cm pots containing Pro-Mix. Two weeks after transplanting, seedlings were sprayed with chlormequat chloride (CCC) at 750 or 1500 ppm and were compared to nontreated plants. A second application was applied 2 weeks later. Growth and development of asters were affected differently depending on cultivars and experimental season. During Spring 1994, a CCC treatment of 750 and 1500 ppm significantly reduced height and width of Dwarf Carpet Mix and Dwarf Spider Mix without affecting the number of flowers and total production time compared to nontreated plants. Growth regulator treatments had no effect on height and width of `Milady Mix' and `Starlight Rose'. However, the 750 ppm CCC treatment reduced the number of flowers produced by these two cultivars. Results obtained in 1993 also are presented.

Effect of CCC on Shoot Growth, Nodulation, Nitrogenase Activity, and Contents of Nitrogen, Ureides, Sugars and Starch in Mung Bean (Vigna radiata [L.] Wilczek var. Guj-2)

Summary Effect of (2-chloroethyl) trimethyl ammonium chloride (CCC) on shoot growth, nodulation, nitrogenase activity, and contents of nitrogen, ureides, sugars and starch in mung bean ( Vigna radiata L. Wilczek var. Guj-2) was studied. CCC application at 1000ppm and 1500ppm markedly reduced the extension growth of the shoot system. CCC at 1000ppm (1000 mg · dm -3 ) significantly increased the number as well as dry weight of root nodules and activity of nitrogenase (acetylene reduction). The contents of total nitrogen, ureides, sugars and starch in shoot and root systes were also increased considerably in response to CCC (1000ppm) treatment. The present study suggests that CCC application may lead to the availability of more photosynthate for nodule formation and nitrogen fixation in mung bean.

Growth Regulator Effects on Aboveground Dry Matter Partitioning during Grain Fill of Spring Barley

It is not clear whether alteration in grain yield due to application of plant growth regulators (PGRs) to cereal crops is caused by altered dry matter accumulation, changes in partitioning of dry matter into grain, or both. A 3‐yr field study was conducted using two widely grown spring barley (Hordeum vulgare L.) cultivars, Cadette and Leger, to evaluate the effects of chlormequat (CCC) (2‐chloroethyl‐N,N,N‐ trimethylammonium chloride) or ethephon (2‐chloroethyl phosphonic acid) on dry matter production and partitioning among plant parts during grain fill. The growth regulators were applied at three stages of crop development. The experiments were conducted on Bearbrook clay soil (fine, mixed, nonacid, Mesic Humaquept) at McGill University, Canada, from 1987 to 1989. Treatments consisted of application of CCC (1.2 kg a.i. ha−1) or ethephon (0.48 kg a.i. ha−1) at Zadoks growth stage (ZGS) 13, 30 and 39. Ethephon application at ZGS enhanced dry matter accumulation in the nongrain plant parts (chaff, culms, leaf blades, and leaf sheaths) in both 1988 and 1989, and decreased grain mass per spike (number of grains per spike and 1000‐ grain weight) in 1989. This resulted in a yield reduction in that year. In 1988, an increased grain mass per spike with ethephon resulted in improved grain yield. For Cadette, CCC treatment also increased dry matter accumulation in leaf blades, leaf sheaths, and chaff in 1988. Grain yield per square meter was also increased by a ZGS‐13 application in that year. In general, this work revealed that PGR application does not increase total dry matter accumulation on a per‐shoot basis, but does affect dry matter partitioning patterns, leading to alterations in grain yield that may be positive or negative depending on the conditions during a given crop year.

ジニアの小花形成に及ぼすわい化剤ウニコナゾール処理の影響

This experiment was conducted to determine the effect of Uniconazol on the morphological response particularly the formation of ray and tubular florets in Zinnia elegans Jacq. which include the tall cultivar Red Sun as well as dwarf cultivars such as Peter Pan Scarlet, Peter Pan Golden, Dreamland Scarlet and Dreamland Yellow. In addition, the effects of other growth retardants such as Ancymidol, CCC and SADH on cultivar Red Sun were also investigated.Growth retardation induced by Uniconazol treatment was more prominent in dwarf cultivars than the tall cultivar Red Sun. In all cultivars treated with Uniconazol, the number of days to flowering was delayed 3-4 days and the flower fresh weight was reduced to less than half of control. The number of ray florets was decreased and tubular florets was increased by Uniconazol treatment in all cultivars especially in 'Red Sun'.Growth retardation induced by Uniconazol was stronger than other growth retardants. The number of days to flowering were delayed 1.4, 2.5 and 3.6 days by Uniconazol, CCC and SADH treatments, respectively. The flower fresh weight was reduced to less than half of control due to Uniconazol, CCC and SADH treatments. All growth retardant treatments except Ancymidol reduced ray floret and increased tubular floret. As a result, the plants treated with growth retardants produced single and half-double flowers.

FARKLI EKİM ZAMANLARINDA KULLANILAN CCC UYGULAMALARININ BEZELYE (Pisum sativum)' DE BİTKİ GELİŞMESİNE VE VERİME ETKİSİ

OZET Farkli ekim zamanlarinda yetistirilen erkenci ve gecici bezelye cesidinde CCC uygulamasinin bitki gelismesine ve verime etkisinin incelendigi bu arastirmadan elde edilen sonuclar su sekilde ozetlenebilir. 1- CCC uygulanmasi her iki bezelye cesidinde de bogum uzunlugunu azaltmis, bogum kalindigim artirmistir. CCC uygulamasinin bu etkisi uc ekim zamaninda da gorulmustur. 2- Bogum uzunlugu ve kalinligi bakimindan IL ekim ama/unda bitki gelismesinin III ekim zamanina gore daha zayif oldugu belirlenmistir. 3- CCC uygulamalarinin bogum sayisina etkisi yillara, cesitlere ve ekim zamanlarina gore degismistir. 4- Bili i boyu genetikle ekim zamanin gecikmesine paralel \ azalmasina neden olmustur. 5- Genelde CCC uygulamalarinin bakla boyuna ve bakla agirligina fazla bir etkisi olmamistir (ozellikle ekim zamaninin bakla agirligina etkisi, CCC uygulamasindan daha fazla olmustur. 6- Uygulamalar bitki basina tek ve cift meyveli cicek salkimi sayisini artirmis, gec el im ise azaltmistir. 7- CCC uygulamasi bitkide hakla sayisini artirmis fakat baklada dune rayisiiti uzalimisnr. 8-1000ppm CCC uygulamasi her uc ekim zamaninda da \ erimi artirmistir. Ancak ekim zamaninin verime olan etkisinin CCC'in etkisinden daha fazla oldugu tesbit edilmistir. THE EFFECTS OF CCC TREATMENTS ON GROWTH AND YIELD OF GARDEN PEAS (Pisum sativum cvs, Kelvedon andWJtecord) GROWN AT DIFFERENT SO WING DATESIN ERZURUM SUMMARY In order to detertnine the effects of CCC treatments on plant growth and yield of garden pea grown at different sowing dates, this study was carried out in 1977 and 1978 on the Agrucultural Experiment Station, Faculty of Agriculture, University cf Ataturk, Erzurum. Seeds of peas cvs. Kelvedon and WJRecord Sown 40 cm aport within-rew spacing 10 cm in plots of 3, Oto 2,8 m on 3 rd and 29 th May and 25 th June in 1977; 17 the and 28 th May and 10 th June in 1978. The treatments consisted ofO, 500,1000 and 2000 ppm CCC (2-chloroethyl) trimethylamonium chloride) as a plant growth regulator. It was sprayed when plants were 3-4 true leaves stage. The experiment was terminated when economical harvesting was over, and yield and yield components were determined. The experiment design was split-split plot. Ali data obtained in this study were subjected to anatysis ofvariance and means separeted by Duncan's Multiple Range Test. The results dotained in this study can be summarized as follows: 1- The CCC treatments decreased of length of internodes ofboth cultivars but increased thickness of internodes in ali sowing dates. 2- In second sowing time length and tickness of internodes were lower than first and third sowings. 3- The effect of CCC treatments on number of nodes varied mth varieties, sowings andyears. 4- In general, length of plant decreased with delaying sowing date. Treatments of CCC decreased the length of plant too. 5- T here was no signiftcant effect of treatments on length and weigth of pods. The effect of sowing dates on weigth of pods was greater than CCC treatments. 6- Treatments of CCC increased the number of clusters single or double poded but late sowings decreased. 7- The treatments of CCC increased number of pods per plant but decreased number of seeds per pod. 8• 500 and 1000 ppm CCC treatments incresed the yield in ali sowings but the effect of sowing date on total yield was greater than CCC treatm

Messung und Dokumentation mikromorphologischer Veränderungen in Pflanzen am Beispiel CCC‐behandelten Sommerweizens mit Hilfe der quantitativen Bildanalyse

Abstract Measurement and documentation of micromorphological changes in plant tissue by means of quantitative image analysis as illustrated with CCC treated spring wheat Growth regulators are used in crop production to influence extension growth of plants and stability of tissues. Knowledge about the mode of action and efficiency of these compounds are based on physiological and morphological studies with the respective plant tissues. Technical deficiencies in both fields quite often hinder the appropriate insight into tissue reaction. In the present study a computer assisted quantitative image analysis system was applied to support precise and fast measurement and documentation of micromorphological effects in plant tissue.Spring wheat (cv. Arkas and Sappo) were treated with 0.75 and 1 I ha−1 CCC at EC 30. For morphological studies plants were harvested at EC 61. Tissue microcuts out of the 1st and 2nd internodium of wheat stem were stained with alcoholic safranin solution and measured with the interactive image analysis system “IBAS I” (Zeiss and Kontron).Stem diameter and stem wall thickness did not change after CCC treatment, while thickness of the selerenchyma ring of the stem was increased significantly. After CCC application average length of cells in the respective tissue decreased up to 15 %, length of internodium up to 27 %. Thickness of cell walls were reduced in the stem tissue of CCC‐treated plants and the number of parenchyma cells increased.According to this investigation stem stabilizing effects of CCC treated wheat stem are based on the increased size of the lignified selerenchyma ring and on increased number but smaller cells in the parenchyma tissue. With the image analysis system used all measurements could be performed at high precision and quickly so that each given parameter is based on at least several hundred single data.

Response of Hordeum distichon cv. Igri (2-row) and H. hexastichon cv. Plaisant (6-row) winter barley to foliar applications of chlormequat

Two-row (cv. Igri) and six-row (cv. Plaisant) winter barley cultivars were incorporated into a field trial at Sutton Bonington (1984–1985) where the effects of chlormequat (CCC) applied at the three-leaf stage (main stem) and the onset of stem elongation were compared. CCC had no influence on lodging as the area cropped with ‘Igri’ completely lodged while no lodging occurred for the cultivar ‘Plaisant’. Neither CCC treatment nor cultivar influenced the rate, duration or pattern of biomass accumulation. CCC application in either the autumn or spring increased harvest index and thus grain yield for both genotypes. Mean grain mass linearly declined as ear population was increased by CCC application, with the number of grains per ear unchanged. A parabolic response of grain yield to the number of ears was inferred and an analysis was used to determine the optimum ear density.