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Salinity stress severely restricts rice growth. Prohexadione calcium (Pro-Ca) modulation can effectively alleviate salt stress in rice. In this study, we explored the effects of Pro-Ca on enhancing salt tolerance in two rice varieties, IR29 and HD96-1. The results revealed that Pro-Ca markedly enhanced root and shoot morphological traits and improved plant biomass under salt stress. Chlorophyll a and b content were significantly increased, which improved photosynthetic capacity. Transcriptomic and metabolomic data showed that Pro-Ca significantly up-regulated the expression of genes involved in E3 ubiquitin ligases in IR29 and HD96-1 by 2.5-fold and 3-fold, respectively, thereby maintaining Na+ and K+ homeostasis by reducing Na+. Moreover, Pro-Ca treatment significantly down-regulated the expression of Lhcb1, Lhcb2, Lhcb3, Lhcb5, and Lhcb6 in IR29 under salt stress, which led to an increase in photosynthetic efficiency. Furthermore, salt stress + Pro-Ca significantly increased the A-AAR of IR29 and HD96-1 by 2.9-fold and 2.5-fold, respectively, and inhibited endogenous cytokinin synthesis and signal transduction, which promoted root growth. The current findings suggested that Pro-Ca effectively alleviated the harmful effects of salt stress on rice by maintaining abscisic acid content and by promoting oxylipin synthesis. This study provides a molecular basis for Pro-Ca to alleviate salt stress in rice. [ABSTRACT FROM AUTHOR]

Prohexadione calcium (EA) and gibberellin (GA) are two different types of plant growth regulators that have different effects on the regulation of plant development. The objective of this study was to evaluate the impacts of EA and GA on rice plant growth, development and morph-physiological traits in two rice varieties: 'Huang Huazhan' and 'Guang Hong 3'. At the three-leaf seedling stage, the plants were treated with 50 mM NaCl 24 h after foliar application of EA (100 mg·L−1) and GA (1 mg·L−1). Data on morphological indexes, osmotic regulators and antioxidant activities were compared with the treatment of EA and GA on the 4th, 7th, 10th and 13th days after NaCl stress. Our data analysis showed that NaCl stress inhibited the leaf area growth of rice seedlings, altered the microstructure and disrupted the antioxidant system, ion uptake and transport balance. The significant increase in malondialdehyde (MDA) content and superoxide anion production rate (O2 · ¯) indicated that NaCl stress caused a severe oxidative stress response to rice seedlings. Treatment with EA and GA activated the antioxidant system under NaCl stress, significantly elevated superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and suppressed the increase in MDA content and the O2 · ¯ production rate. Under NaCl stress, EA and GA treatments improved the osmoregulatory balance, significantly increased soluble protein and proline contents and maintained lower Na+/K+ levels. EA and GA treatments significantly increased the K+ and Ca2+ contents, thereby maintaining ionic balance, which was favorable for maintaining the growth of rice seedlings. In this study, moth plant growth regulators maintained the growth and development of rice seedlings under NaCl stress by inducing an increase in osmoregulation and antioxidant levels, reducing the degree of membrane damage and regulating the selective uptake of ions by rice seedlings. Current findings also clarified that foliar application of EA was more effective than GA in three-leaf seedlings by enhancing the morph-physiological and antioxidant parameters under NaCl stress. [ABSTRACT FROM AUTHOR]

Prohexadione calcium (EA) and gibberellin (GA) are two different types of plant growth regulators that have different effects on the regulation of plant development. The objective of this study was to evaluate the impacts of EA and GA on rice plant growth, development and morph-physiological traits in two rice varieties: ‘Huang Huazhan’ and ‘Guang Hong 3’. At the three-leaf seedling stage, the plants were treated with 50 mM NaCl 24 h after foliar application of EA (100 mg·L−1) and GA (1 mg·L−1). Data on morphological indexes, osmotic regulators and antioxidant activities were compared with the treatment of EA and GA on the 4th, 7th, 10th and 13th days after NaCl stress. Our data analysis showed that NaCl stress inhibited the leaf area growth of rice seedlings, altered the microstructure and disrupted the antioxidant system, ion uptake and transport balance. The significant increase in malondialdehyde (MDA) content and superoxide anion production rate (O2·¯) indicated that NaCl stress caused a severe oxidative stress response to rice seedlings. Treatment with EA and GA activated the antioxidant system under NaCl stress, significantly elevated superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and suppressed the increase in MDA content and the O2·¯ production rate. Under NaCl stress, EA and GA treatments improved the osmoregulatory balance, significantly increased soluble protein and proline contents and maintained lower Na+/K+ levels. EA and GA treatments significantly increased the K+ and Ca2+ contents, thereby maintaining ionic balance, which was favorable for maintaining the growth of rice seedlings. In this study, moth plant growth regulators maintained the growth and development of rice seedlings under NaCl stress by inducing an increase in osmoregulation and antioxidant levels, reducing the degree of membrane damage and regulating the selective uptake of ions by rice seedlings. Current findings also clarified that foliar application of EA was more effective than GA in three-leaf seedlings by enhancing the morph-physiological and antioxidant parameters under NaCl stress.

Abstract Feathering in apple nursery trees is a critical operation used to increase the quality of planting material. Plant growth regulators (PGR) could be used to form feathers in apple nursery trees. The main goal was to study the impact of different PGR and concentrations on feathering promotion in different nursery apple trees. The study had three different trials where the specific aims were to study the impact of: i) different rates of 6-benzyladenine (6-BA); ii) different PGR (6-BA and 6-BA + GA4+7) on feathering promotion, and; iii) 6-BA on feathering promotion and prohexadione calcium (P-Ca) on trunk thickening under greenhouse conditions. Both 6-BA and 6-BA + GA4+7 were effective inducing feathering in the different cultivars tested. 6-BA reduced final young plants grafted height only in one out of three seasons, reducing an average of 15 and 10 cm on ‘Early Red One’ and ‘Fuji’ apple nursery trees, respectively. P-Ca reduced tree growth rate 4-5 weeks after sprayed, but the difference did not persist until the end of the season. Trunk diameter was not affected by the different plant growth regulators and concentrations tested. 6-BA alone or in combination with GA4+7 is an efficient tool to feathering formation in different nursery apple cultivars and conditions.

Prohexadione calcium (Pro-Ca), as a growth retardant, can effectively alleviate the damage of salt stress to plants. In order to explore the effects of NaCl stress on the physiological characteristics and panicle traits of rice plants as well as the alleviating effect of Pro-Ca at the booting stage, we performed pot experiments on two rice cultivars: conventional rice 'Huanghuazhan' and hybrid rice 'Xiangliangyou900'. Rice plants were treated with 0.3% NaCl 48 hours after Pro-Ca (100 mg L-1) treatment to study the effects of Pro-Ca on the physiological characteristics of the leaves and panicles, as well as the panicle and yield traits of rice under salt stress. Our analysis indicated that NaCl treatment inhibited the morphological growth parameters and photosynthetic efficiency, destroyed the antioxidant defense systems of leaves and panicles, increased soluble protein and proline in both rice cultivars. Foliar application of Pro-Ca significantly increased the leaf area, uppermost internode length, panicle length, panicle weight, number of primary branches, number of grains per panicle, seed setting rate and yield under salt stress. Pro-Ca application significantly affected chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and apparent mesophyll conductance (AMC) in NaCl-treated rice cultivars compared with NaCl treatment alone. Moreover, Pro-Ca also increased ascorbic acid (AsA) content, enhanced superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity, and further increased the accumulation of soluble protein and proline in leaves and panicles. These results illustrated that foliar application of Pro-Ca at the booting stage could alleviate the damage caused by NaCl stress by regulating the physiological and metabolic processes of rice plants, thereby enhancing the stress resistance of the plants, increasing total rice yield in salt stress conditions. [ABSTRACT FROM AUTHOR]

In 2020, a greenhouse experiment was conducted to investigate the suppression of annual bluegrass (Poa annua), which is a difficult weed to manage in cool-season in turfgrass mixtures on football pitches. The efficacy of prohexadione calcium (Pc), ethephon (Eth) and Pseudomonas fluorescens against P. annua, Lolium perenne and Poa pratensis was tested, as the latter two most commonly occur in turfgrass mixtures on football pitches. Mesotrione (Mes) was used as a positive control, and nontreated grass was used as a negative control. Only a single grass species was sown in each pot. Treatments were randomly distributed for two experiments conducted separately: first – unmown grass before the beginning of spraying and second – grass mowed before the beginning of spraying. In both experiments, plant height and the number of tillers were measured/counted several times during the growing season. In both experiments, grasses were sprayed six times with Pc, Eth and P. fluorescens, while Mes was applied twice. Based on the performed study, the efficacy of the tested products is connected to grass species and whether the grass was mowed/cut before spraying. It has been detected in the present study that spraying with Pc could reduce the height of annual bluegrass, while spraying with P. fluorescens has reduced the number of tillers. Spraying was more effective on grasses that were mowed/cut before the beginning of spraying. Mes should cause severe damage to annual bluegrass but without confirmation in this study. Results of this study have indicated that the application of Pc and P. fluorescens can inhibit the spread of annual bluegrass in football pitches; however, testing their effectiveness against P. annua under field conditions should be performed as well.

Foliar sprays of growth regulators have commercial potential for improving the performance of some of the parameters associated with alternate bearing in pecan trees. The objective was to evaluate the behaviour of alternate bearing through analysis of seasonal variations in buds and leaflets of non-structural carbohydrates (glucose, fructose, sucrose, and starch), mineral nutrients (N-total, P, K+, Ca2+, Mg2+, Fe2+, Cu2+, Mn2+ and Zn2+), yield components (nut weight per kilogram and kernel percentage) and oxidative metabolism (superoxide dismutase, hydrogen peroxide, catalase, guaiacol peroxidase and antioxidant capacity) in cv. Wichita pecan trees in response to foliar applications of gibberellic acid (50 mg L−1), calcium prohexadione (500 mg L−1) or thidiazuron (10 mg L−1). The experiment was of a completely randomized experimental design with five replicates. Foliar growth regulator (GRs) sprays help maintain the concentration of non-structural carbohydrates in the leaflets and buds between the evaluation years. With the exception of K+ (12.9 and 10.9 g kg−1) and Zn2+ (45.1 and 30.5 mg kg−1), the GRs did not show any effects on the concentrations of the foliar mineral nutrients. The results suggest foliar sprays of gibberellic acid improve the performance of parameters associated with alternate bearing, including oxidative metabolism. [ABSTRACT FROM AUTHOR]

ABSTRACT Carya illinoinensis (Wangenh.) K. Koch. is a deciduous fruit species with high economic impact and nutritional value that exhibits alternate bearing behavior. In this study, the concentration of foliar nutrients, non-structural carbohydrates and yield were evaluated in cultivar Western Schley pecan in response to the foliar application of gibberellic acid (50 mg L-1 GA3), prohexadione calcium (500 mg L-1 PCa) and thidiazuron (10 mg L-1 TDZ).The statistical analysis reveals that between agricultural cycles, the treatments showed no variation in the foliar concentration of nitrogen total (N-total), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), manganese (Mn) and non-structural carbohydrates (fructose, glucose, sucrose and starch). However, the application of PCa showed no significant effect on the concentration of phosphorus (P) (1.5 and 1.9 g kg-1). On the other hand, the concentration of zinc (Zn) (27.0-60.1 mg kg-1) showed a significant difference between years, with no effect due to the application of growth bioregulators. The trees treated with GA3 minimized alternate bearing by presenting similar values (12.4 and 15.3 kg tree-1) of yield. Likewise, the applied treatments did not affect the nut weight per kilogram (kg) (5.5-6.8 g) and kernel percentage (56.5-60.8). These data provide a new perspective on the complex nature of alternate bearing production in cultivar Western Schley pecan and are interpreted to indicate that alternate production could be regulated by carbohydrate reserve, nutrient concentration, and gibberellins.

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The pecan [Carya illinoinensis (Wangenh.) K. Koch.] is a deciduous species with high economic importance and nutritional value that exhibits alternate bearing. The mitigation of alternate bearing through the floral initiation of pistillate flowers is very important to improve the yield and nut quality. The aim of this research was to evaluate the effect of the application of some growth bioregulators on the yield and nut quality in pecan. The application of gibberellic acid (GA3 - 50 mg L-1), thidiazuron (TDZ - 10 mg L-1) and prohexadione calcium (PCa - 500 mg L-1) was carried out during two years (2017 and 2018) on young Western Schley pecan trees from an orchard located in Chihuahua, Mexico. The foliar application of growth bioregulators minimized alternate bearing by maintaining the number of fruits set before harvest between the evaluation years. Between the evaluated production cycles, the data obtained indicate that the application of growth bioregulators affected the yield, although the nut weight per kilogram remained similar with TDZ (5.6 and 5.7 g). PCa was the best treatment for both parameters. Likewise, significant variation in the alternate bearing index with respect to the control was observed. On the other hand, the kernel percentage showed the best behavior between years and treatments with the use of GA3 and PCa. The use of the evaluated growth bioregulators could be an agronomic management strategy to minimize alternate bearing in Western Schley pecan trees. [ABSTRACT FROM AUTHOR]

BACKGROUND: The obligatory sunflower root parasite Orobanche cumana Wallr. deprives its host of essential nutrients, resulting in a dramatic reduction in yield and biomass. A post-emergence application with an imidazolinone herbicide on an imidazolinone-tolerant sunflower is highly effective against O. cumana. The herbicide inhibits the enzyme acetohydroxy acid synthase and consequently, growth of the parasite is inhibited, although the sunflower survives the treatment through mutations in the target enzyme. Interestingly, field studies have shown that a combined application of an imidazolinone herbicide with prohexadione resulted in reduced emergence of O. cumana compared with the sole application of the herbicide. The aim of this study was to investigate whether prohexadione is herbicidal to O. cumana. RESULTS: Prohexadione was rapidly distributed within the sunflower, reaching the roots, the site of O. cumana attack, as early as 6 h after application (HAA) on sunflower leaves. A direct impact of prohexadione on O. cumana germination was investigated and a half-maximal inhibitory concentration (IC50) of 84 μM prohexadione was found. In addition, the inhibition of germination by prohexadione was terminal, meaning that O. cumana seeds died after prohexadione contact as soon as they were primed for germination. Additionally, excretion studies showed that a small proportion of the applied prohexadione was excreted by sunflower roots. CONCLUSION: We show that prohexadione is an inhibitor of O. cumana germination and that the growth regulator is found in sunflower roots shortly after application. We hypothesize that prohexadione is excreted in sufficient amounts from the sunflower roots, therefore having a direct impact on O. cumana germination. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to evaluate the effect of different aminoethoxyvinilglycine (AVG), thidiazuron (TDZ) and prohexadione calcium (P-Ca) rates sprayed at different timings on fruit set, yield, and fruit quality of ‘Rocha’ pear trees in different climatic conditions of Southern Brazil. The study was performed in two commercial orchards located in São Joaquim, SC (2015/2016) and Antônio Prado, RS (2016/2017). Plant material consisted of ‘Rocha’ pear trees grafted onto Pyrus calleryana and quince rootstock ‘BA29’ in São Joaquim and Antônio Prado, respectively. Treatments consisted of AVG, TDZ and P-Ca sprayed at different rates and timings. Trunk cross-sectional area increase, fruit set, thinned fruit, fruit per tree, yield, average fruit weight, projected yield, yield efficiency, fruit length, fruit diameter, L/D ratio, seed number, flesh firmness, and soluble solids content were assessed. Fruit set and yield were consistently increased by AVG in all experiments. Fruit set was not affected by P-Ca and was significantly decreased by TDZ. However, yield was positively affected by P-Ca 100 mg L–1 sprayed at full bloom + 7 days after full bloom and TDZ 10 mg L–1 at full bloom. Fruit size was consistently increased by TDZ.

Foliar sprays of growth regulators have commercial potential for improving the performance of some of the parameters associated with alternate bearing in pecan trees. The objective was to evaluate the behaviour of alternate bearing through analysis of seasonal variations in buds and leaflets of non-structural carbohydrates (glucose, fructose, sucrose, and starch), mineral nutrients (N-total, P, K+, Ca2+, Mg2+, Fe2+, Cu2+, Mn2+ and Zn2+), yield components (nut weight per kilogram and kernel percentage) and oxidative metabolism (superoxide dismutase, hydrogen peroxide, catalase, guaiacol peroxidase and antioxidant capacity) in cv. Wichita pecan trees in response to foliar applications of gibberellic acid (50 mg L−1), calcium prohexadione (500 mg L−1) or thidiazuron (10 mg L−1). The experiment was of a completely randomized experimental design with five replicates. Foliar growth regulator (GRs) sprays help maintain the concentration of non-structural carbohydrates in the leaflets and buds between the evaluation years. With the exception of K+ (12.9 and 10.9 g kg−1) and Zn2+ (45.1 and 30.5 mg kg−1), the GRs did not show any effects on the concentrations of the foliar mineral nutrients. The results suggest foliar sprays of gibberellic acid improve the performance of parameters associated with alternate bearing, including oxidative metabolism.

Abstract: The objective of this work was to evaluate the effect of different techniques to modify grape cluster architecture on the incidence and severity of botrytis bunch rot, as well as on the viticultural performance of the 'Sauvignon Blanc' grapevine (Vitis vinifera). Associated with fungicides, four treatments were tested: control, 30 ppm gibberellic acid sprayed at full bloom, 1,000 ppm prohexadione calcium sprayed at full bloom, and berry thinning at the stage of beginning of berry touch. The experiment was carried out in the 2015, 2016, and 2017 vintages. Clusters were treated with fungicides during the stages of full bloom, beginning of berry touch, veraison, and around 15 days before harvest. Berry thinning does not cause losses in the yield and quality of 'Sauvignon Blanc', and, despite having little effect on cluster architecture, is effective in reducing the incidence and severity of Botrytis cinerea. Prohexadione calcium improves grape phenolic maturation, is effective in reducing the incidence and severity of B. cinerea, and reduces cluster compactness by decreasing berry diameter. The application of gibberellic acid spray at full bloom is not recommended because it decreases yield and bud fertility and increases berry susceptibility to B. cinerea infection.

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Plant Protection is the property of Institute of Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the quality of seeds and yield of winter wheat under different retardants application. The two years field trials on winter wheat were carried out in the Institute of Plant Protection - National Research Institute in Poznan (Poland). Treatments consisted of trinexapac-ethyl, chlormequat and prohexadione calcium applied in mixtures with paraffin oil adjuvant or organosilicone surfactant in BBCH 31 growth stage of winter wheat. No lodging occurred in any experimental year. The retardants had varying effect on the quality parameters of wheat grain. The highest fluctuations in the content of protein, gluten and the Zeleny value were observed after the application of chlormequat chloride. Starch content in wheat grain, regardless of the retardant application method, was negatively correlated with others grain quality parameters evaluated in the experiment. Depending on the year of study and weather conditions, increased or decreased wheat quality. [ABSTRACT FROM AUTHOR]

In this experiment, the effect of prohexadione calcium on the cold resistance physiological index of tobacco seedlings were investigated with a tobacco variety YY87. The results showed that compared with the control spraying deionized water under low temperature, spraying prohexadione calcium could induce the resistant of tobacco seedlings suffering low temperature. Under conditions of low temperature stress, spraying prohexadione calcium made the increase of membrane lipid peroxidation product malondialdehyde( MDA) content slowly, increase proline content, weaken the inhibition of SOD, POD, CAT activity under cold stress, enhance enzymes activity; Slowing the decomposition of chlorophyll, chlorophyll fluorescence parameters of tobacco leaves under low temperature stress significantly increased, reduce the influence of low temperature on photosynthesis of plant leaves; While improving root activity, decrease inhibitory effect of low temperature on biomass accumulation of tobacco seedlings, improve cold resistance of tobacco seedlings, thus promote the growth of tobacco seedlings. [ABSTRACT FROM AUTHOR]

Prohexadione calcium (Pro-Ca), as a growth retardant, can effectively alleviate the damage of salt stress to plants. In order to explore the effects of NaCl stress on the physiological characteristics and panicle traits of rice plants as well as the alleviating effect of Pro-Ca at the booting stage, we performed pot experiments on two rice cultivars: conventional rice ' Huanghuazhan ' and hybrid rice ' Xiangliangyou900 '. Rice plants were treated with 0.3% NaCl 48 hours after Pro-Ca (100 mg L -1 ) treatment to study the effects of Pro-Ca on the physiological characteristics of the leaves and panicles, as well as the panicle and yield traits of rice under salt stress. Our analysis indicated that NaCl treatment inhibited the morphological growth parameters and photosynthetic efficiency, destroyed the antioxidant defense systems of leaves and panicles, increased soluble protein and proline in both rice cultivars. Foliar application of Pro-Ca significantly increased the leaf area, uppermost internode length, panicle length, panicle weight, number of primary branches, number of grains per panicle, seed setting rate and yield under salt stress. Pro-Ca application significantly affected chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and apparent mesophyll conductance (AMC) in NaCl-treated rice cultivars compared with NaCl treatment alone. Moreover, Pro-Ca also increased ascorbic acid (AsA) content, enhanced superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) activity, and further increased the accumulation of soluble protein and proline in leaves and panicles. These results illustrated that foliar application of Pro-Ca at the booting stage could alleviate the damage caused by NaCl stress by regulating the physiological and metabolic processes of rice plants, thereby enhancing the stress resistance of the plants, increasing total rice yield in salt stress conditions., Competing Interests: The authors declare there are no competing interests., (©2023 Huang et al.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

European chestnut ( Castanea sativa Mill) explants were cultured in vitro in the presence of five different cytokinins in three concentrations (benzyladenine, 2-isopentyladenine, kinetin, forchlorfenuron and thidiazuron). Benzyladenine at the concentration of 2 mg L −1 was the most effective, resulting in the highest shoot (6.0) and node number (23.05). At the rooting stage indole-3-butyric acid at 4 mg L −1 was more efficient in promoting rhizogenesis (up to 81.25%) than 1-naphthalene acetic acid (up to 65%). The most efficient plant growth regulators, at each in vitro stage, were combined with the plant growth retardants, mepiquat chloride, paclobutrazol and prohexadione calcium along with cyclanilide, in order to assess their efficacy on improving proliferation rate and/or rooting response. Mepiquat chloride at 0.1 mg L −1 when combined with bezyladenine at 2 mg L −1 resulted in significant increase of shoot and node number (5.9 and 30.6 respectively) compared to BA alone (4.65 and 26.85 respectively). The combination of mepiquat chloride at 0.01 mg L −1 or prohexadione calcium at 0.1 mg L −1 with BA also promoted the shoot number compared to control (5.7 and 5.75 respectively). Plant growth retardants did not further enhance rooting responses of chestnut explants. In conclusion, mepiquat chloride could be a valuable tool in combination with benzyladenine in order to improve multiplication rate of juvenile chestnut during the proliferation stage. [ABSTRACT FROM AUTHOR]