首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
The new growth retardants mepiquat chloride (a quaternary ammonium compound of the piperidinium type, coded BAS 083 00W) and a ternary sulphonium carbamate (coded BTS 44 584) were compared with ancymidol (A-Rest or Reducymol) and chlormequat chloride (Cycocel) for their ability to dwarf virus-free and virus-infected (ordinary) Mid-Century Hybrid lily cultivar ‘Enchantment’. Single compost drenches were given 3 weeks after transferring plants to the glasshouse.Compared with the virus-infected control plants, virus-free controls were 62% taller and 33% greater in leaf spread; floret number was approximately doubled and floret diameter was increased by 12%, but flowering was delayed by 6.5 days. The length of the lower stem bearing dead leaves was 15% of the total in virus-infected controls and 3% of the total in virus-free controls.Ancymidol, chlormequat chloride and mepiquat chloride were all effective growth retardants, and were without adverse side-effects. On a concentration basis, mepiquat chloride was 2–2.5 times as active as chlormequat chloride in reducing stem extension, but ancymidol was several orders of magnitude more active than both those compounds. With BTS 44 584, the maximum reduction in stem length obtained was 16% compared to controls. The decreases in stem extension were more pronounced, in both percentage and absolute terms, in the virus-free bulbs. Nevertheless, for a given retardant treatment, plants of the virus-free stock remained taller than those of the virus-infected stock. As a result, 2–3 times the amount of an active retardant was required by virus-free than by virus-infected plants in order to produce similar stem lengths at flowering. Effects of the retardants on the time of flowering, flower number, floret diameter and leaf spread were small, but increasing concentrations of all chemicals progressively increased the proportion of the stem bearing dead leaves.The effects of ancymidol, chlormequat chloride and mepiquat chloride persisted in the year after treatment.  相似文献   

2.
Stem elongation of Lilium cultivars ‘Black Beauty’, ‘Jamboree’ and ‘Nutmegger’ was lessened by treating the bulbs with ancymidol (10 p.p.m.) or ethephon (500 p.p.m.). Ancymidol was the more effective inhibitor of stem elongation, although applied at a much lower concentration. Application of the growth regulators prior to a dormancy-breaking cold treatment provided more effective control of stem elongation than post cold-treatment application. The total number of flowers and the number of secondary flowers per stem of ‘Black Beauty’ and ‘Nutmegger’ were increased by treating the bulbs with ancymidol. However, unlike the optimal time for lessening stem elongation, enhancement of flower production was greatest when ancymidol was applied after completion of the cold treatment. Ethephon was unsatisfactory, since it inhibited flower production by ‘Black Beauty’ and ‘Nutmegger’, while ‘Jamboree’ was relatively insensitive to it, as indicated by a lack of inhibition of flower production and a small degree of inhibition of stem elongation.  相似文献   

3.
The new growth retardants piproctanyl bromide (Alden or Stemtrol), dikegulac-sodium (Atrinal), PP 528 (a phenyl tetrazole compound) and 2,3-dihydro-5,6-diphenyl-1,4-oxathiin (coded UBI-P293) were compared with the established compounds chlormequat chloride (Cycocel), ancymidol (A-Rest or Reducymol) and chlorphonium chloride (Phosfon), for their ability to dwarf Mid-Century Hybrid lily cultivars ‘Enchantment’ and ‘Joan Evans’. Single compost drenches were given 2–3 weeks after transferring plants to the glasshouse.Piproctanyl bromide at high concentrations (2000 mg a.i. per plant) produced some dwarfing, as did chlorphonium chloride (at 250 mg a.i. per plant). Chlormequat chloride produced a similar response at 1250 mg a.i. per plant, but on a concentration basis ancymidol was by far the most active compound (only 0.25–0.50 mg a.i. per plant was required). Plant and flower quality was generally good with these 3 chemicals.Dikegulac-sodium reduced stem length but prevented the development of flower buds and the plants senesced. PP 528 also restricted stem extension but plant quality was unsatisfactory; increasing concentrations led to smaller florets, weaker stems and drooping leaves. UBI-P293 produced as great a reduction in stem length as did ancymidol, and 100 mg a.i. per plant was as active as 500 mg. However, as the concentration was raised there was a decrease in floret size and number.  相似文献   

4.
Ancymidol, chlormequat, and daminozide were evaluated as growth retardants on forced dahlias. Only ancymidol was effective in reducing plant height, and at 0.25 to 2.0 mg per plant it did not affect the date of flowering, flower size, or the number of shoots produced from the tuberous roots. Treatment by soil drench was more effective than a foliar spray. The most consistent effects were obtained when ancymidol was applied 2 weeks after planting. Dahlia cultivars differed in the degree of response to ancymidol. Optimum rates must be determined for the cultivars which are suitable for pot plant forcing for spring marketing.  相似文献   

5.
Biennial bearing is a serious economic problem facing mango growers. In the past it has been attributed to the lack of new growth and insufficient carbohydrate and nitrogenous reserves following a year of heavy cropping. The results of our studies conducted over a period of 4 years have shown that ethephon (200 ppm) could be used to induce heavy flowering and fruiting during the “off year” in the notedly biennial bearing cv. ‘Langra’. The spray applications of ethephon should be started during September and continued four to five times at 15–20 days interval. Higher concentrations of ethephon, viz. 500, 1000 and 2000 ppm, induced moderate to heavy leaf abscission in the experimental trees. Consecutive applications of 200 ppm ethephon for a period of 3 years did not show any decline in the vigour and yielding ability of the treated ‘Langra’ mango trees.  相似文献   

6.
An improved method of treating Lilium cultivars ‘Enchantment’ and ‘Harmony’ with the growth regulators Ancymidol, CCC, and Ethrel is described. When bulbs were treated, prior to planting, by immersing them for 12 h in aqueous solutions of the growth regulators, shoot elongation was more effectively inhibited than when the chemicals were applied as soil drenches. Ancymidol was the most potent inhibitor of stem elongation. Although Ethrel effectively inhibited stem growth during the first treatment season, it resulted in increased elongation of the renewal shoots. Ethrel interfered with apical meristematic activity, and induced early flower senescence. The inhibitory effects of a single bulb-dip with Ancymidol and CCC were evident on the growth of the renewal shoots in the following non-treatment season.The bulb-dip procedure offers several advantages: chemicals can be applied effectively at a much earlier development stage of the shoot; more effective control of shoot elongation is possible; significant control of shoot elongation may be obtained with lower concentrations of a growth regulator; one application of the growth regulator affected growth of the current season's shoot and also the growth of the renewal shoot in the following season; bulbs may be pretreated for use either as pot plants or for landscaping; chemically pretreated bulbs can be readily packaged and distributed without further chemical treatments being required.  相似文献   

7.
Summary

The first experiment studied the effect of applying ethylene biosynthesis regulating compounds (ethephon 1000 ppm, silver thiosulphate 0.4 mM and cobalt chloride 5 mM) on the growth and development of Liatris spicata cv. Callilepis. The results pointed to the important growth retardant properties of ethephon and the increased number of flowering stems per corm which could be obtained by pre-planting application. A second experiment aimed to optimize ethephon treatment in Liatris by applying the growth retardant in different concentrations (100, 700, 1300, 1900 and 2500 ppm) at three stages of development: stage I (pre-planting), stage II (immediately after the formation of basal leaf rosette) and stage III (when the main shoot began its rapid longitudinal growth). Besides confirming the effects produced by ethephon in the first experiment, the results suggested that the application of high ethephon concentrations (1900 and 2500 ppm) during stage II of growth produced many miniature flowering stems coming from the principal or secondary shoot.  相似文献   

8.
The response of Mid-Century Hybrid lily ‘Enchantment’ to ancymidol has been investigated in two experiments. In the first, three dates of application were employed, the earliest at inflorescence initiation, the second and third 10 and 20 days later, respectively. Application (750 μg/plant as a 15 ppm soil drench) on the second date produced the shortest plants, a result attributed to more extensive uptake by a better-developed root system. Plants subjected to treatment on the third date were, by then, too tall for the maximum dwarfing effect to occur. Flower number was unaffected by treatment, but ancymidol delayed anthesis by between 4 and 6 days and promoted earlier senescence of basal leaves.In the second experiment, interactions between gibberellic acid (GA3) and ancymidol were demonstrated. Increasing amounts of GA3 (20, 200 and 2 000 μg/plant as aqueous applications to the shoot tip) progressively counteracted the dwarfing effect of ancymidol (500 μg/plant as a 10 ppm soil drench) and, in the absence of ancymidol, 2 000 μg GA3/plant significantly promoted stem extension. Flower number was slightly decreased by GA3 in the absence of ancymidol. An ancymidol-induced delay in anthesis of almost 5 days was progressively reduced by increasing levels of GA3, which, in the absence of ancymidol, did not significantly influence the time of anthesis. Applied separately, neither ancymidol nor GA3 significantly affected pedicel length of the first flower, but increasing levels of GA3 progressively promoted pedicel elongation in the presence of ancymidol.  相似文献   

9.
The influence of soil drench applications of ancymidol (0.5 mg), GA3 (25 mg), and Ga4+7 (25 mg) was determined on the growth and development of the tulip under greenhouse conditions. Ancymidol applied on greenhouse day 1 or 6 significantly reduced the total length of the scape. Maximum reduction in growth occurred in the first internode, with a declining effect on internodes 2, 3 and 4. GA4+7 applied simultaneously with ancymidol completely reversed the ancymidol effects. GA3 was relatively ineffective. Compared to control plants, ancymidol reduced the number of cell divisions in the first internode, but not in the fourth internode. Cells of ancymidol treated plants were reduced in length and exhibited greater radial expansion. Ancymidol reduced the fresh weight of the stem and tended to conserve the fresh weight of the mother scales. The effect on the leaves and roots was variable. Ancymidol tended to increase the fresh weight of the daughter bulblets. There was no significant effect of ancymidol or the GA's on floral morphology or the number of days to flower in the greenhouse.  相似文献   

10.
New Guinea Impatiens hybrids ‘Morning Star’, ‘Arctic Star’, ‘Pink Eyes’ and ‘Star Fire’ were tested for their response to (2-chloroethyl) trimethylammonium chloride (chlormequat, CCC), α-cyclopropyl, α-4-methoxypropyl, α-5-pyrimidine methanol (ancymidol, EL531) and succinic acid-2, 2-dimethylhydrazide (SADH). Treatments included the concentrations recommended for other bedding-plants plus extremely high concentrations, and were applied as a soil drench or a spray, with or without a surfactant. Results indicated highly significant cultivar × chemical interactions, which precludes the making of specific recommendations that would apply to all cultivars. Of the chemicals tested, ancymidol generally showed the largest and most stable effect. Where height was reduced, the reduction was usually less than 10% of total height. Because genetically controlled height variation in these Impatiens is much greater, breeding for the desired plant height should be more economical than chemical modification.  相似文献   

11.
Response of potted tulips to new and established growth-retarding chemicals   总被引：1，自引：0，他引：1  
A range of growth-retarding chemicals was evaluated for their potential in the production of compact pot-grown tulips: ancymidol, piproctanyl bromide (Alden), dikegulac-sodium (Atrinal), a phenyl tetrazole compound (coded PP528), 2,3-dihydro-5,6-diphenyl-1,4-oxathiin (coded UBI-P293), chlorphonium chloride (Phosfon), 2-chloroethylphosphonic acid (Ethrel), and 5 morphactins. All chemicals were applied as single soil drenches 1–2 days after transferring plants to the glasshouse. Mid- and late-season forced bulbs of cultivars ‘Apeldoorn’, ‘Paul Richter’ and ‘Rose Copland’ were used.Piproctanyl bromide and chlorphonium chloride were ineffective, the former causing some stimulation of top internode extension. Ethrel at high concentrations gave a slight reduction in first internode length only, associated with a degree of flower-bud blasting. Dikegulac-sodium gave some reduction in stem and petal length, depending on cultivar. PP528 induced flower-bud blasting, adverse changes in flower colour and reduced petal length at concentrations which effectively shortened stems. Morphactins were toxic or caused flower-bud blasting and other floral abnormalities at high concentrations; at lower doses most morphactins reduced first internode length, while some increased length of the upper internodes, inducing nastic curvature and occasionally altering flower shape. Most effective height control was achieved with ancymidol and UBI-P293, the latter being the more active (at the concentrations tested); flower quality was good. In one experiment only, ancymidol slightly delayed flowering. High concentrations of UBI-P293 gave rise to some flower-bud blasting, especially in ‘Rose Copland’ which showed other adverse side-effects such as decreased length and longevity of the flowers, not only with UBI-P293 but also with higher doses of some other retardants.  相似文献   

12.
Summary

A series of trials in Tasmania examined the thinning effects of ethephon and NAA on ‘Red Fuji’ apple. In the ethephon trials, concentrations from 25 to 600 ppm were applied at full bloom (FB) or 14 days after full bloom (AFB) to trees on either seedling or M.M.106 rootstocks. The NAA trial involved spraying concentrations of 5, 10 or 15 ppm at FB or 14 days AFB to trees on seedling rootstocks. Ethephon thinning of ‘Red Fuji’ was similar at FB and 14 days AFB. The dependence of fruit thinning on ethephon concentration was described by fitting non-linear response curves. These relationships were stronger and less variable for M.M.106 than seedling trees. Ethephon proved a satisfactory thinner for trees on both rootstocks. At the high spray volume used, the preferred concentrations at both FB and 14 days AFB would be 25 or 50 ppm for seedling and 100 or 200 ppm for M.M.106 rootstocks. NAA under-thinned at 5 ppm and over-thinned at 10 and 15 ppm at both FB and 14 days AFB. No firm recommendation can be given for NAA as a thinner of ‘Fuji’ at this stage.  相似文献   

13.
In order to determine the proper time to harvest paprika pepper (Capsicum annuum L.) fruits to obtain maximum extractable color, two maturity indexes were evaluated. Most consistent results were obtained when fully shriveled fruits were harvested.Foliar applications of ethephon (50, 100, 200 and 500 ppm) were made on two cultivars, ‘Paprika-505’ and ‘Paprika-D.Z.’. Total extractable color and capsanthin content were determined using fully shriveled pericarp tissue. Some flower and leaf abscission was caused by treating plants with 500 ppm ethephon and leaves of plants treated with 200 or 500 ppm ethephon turned yellow. Ethephon stimulated ripening and increased the total extractable color and capsanthin levels of paprika fruits. ‘Paprika-505’ contained more total extractable color and capsanthin than ‘Paprika-D.Z.’ as a result of ethephon treatment.  相似文献   

14.
Summary

Experiments were conducted to determine the appropriate photoperiod, light intensities and sources, and growth regulators, necessary to produce Trachelium caeruleum as a commercially acceptable potted plant. T. caeruleum behaved as an LDP with a critical photoperiod of 14 h necessary for flower initiation but was day neutral for subsequent flower development (from macroscopic bud visibility to anthesis). Providing long days by daylength extension using metal halide (MH) lamps to provide high irradiance resulted in significantly earlier flowering and more flowers than using either MH or incandescent lamps at low irradiance. The use of incandescent lamps to extend the day resulted in slower flowering and fewer flowers than using MH lamps at the same irradiance. Daminozide was effective for controlling plant height but ancymidol and chlormequat were ineffective. Removal of the terminal bud resulted in more compact plants, and more blooms per plant, but delayed flowering by approximately one week.  相似文献   

15.
The formation of flower buds in Clerodendrum seems not to be affected by day length, but the development of the buds is delayed in long days. When long days were established by means of low-intensity illumination with incandescent lamps, few flowers developed and the stems elongated considerably even at a day length of 16 hours. When fluorescent lamps were used for day-length extension, short shoots with many flowers were obtained even in 24-hour days. Flower development was also delayed by gibberellic acid (GA3), but promoted by chlormequat both in short and long days. Shoot elongation was retarded by chlormequat and promoted by GA3.Plants obtained from commercial greenhouses varied considerably with respect to growth and flowering. By selection a clone was obtained which flowered richly on short shoots. Shoot elongation stopped when flowering began. A ‘negative’ selection gave rise to a clone which flowered sparsely and in which shoot elongation was not influenced by flowering.  相似文献   

16.
In summer (August) planting of chilled cv. Tioga strawberry runners, under Israeli growing conditions, there is excessive runner production until mid-December. These runners are removed manually several times during the autumn season. Frequent runner removal had no salutary effect on subsequent flowering and yield. PP-413 inhibited runner production and development highly significantly, but at high concentrations (1 000–2 000 ppm) it had an adverse effect on yield. Ancymidol (25 ppm) had almost no effect on runner development.  相似文献   

17.
Plant height at flowering was reduced in Easter lily (Lilium longiflorum Thunb. cultivar ‘Nellie White’) by momentarily dipping the bulbs in 100 or 264 mg l?1 solutions of ancymidol [α-cyclopropyl-α-(p-methoxyphenyl)-5-pyrimidinemethanol] prior to planting. The number of flowers was unaffected, and days to flower increased slightly at the highest concentration. This method of application is more effective than soil drench and foliarspray applications.  相似文献   

18.
Summary

The effect of three arbuscular mycorrhizal (AM) inocula at four available levels of phosphorus (8.41, 12.53, 13.63 and 14.6 ppm) in non-disinfected soil was studied on the growth, flowering, P uptake and root colonization in micropropagated bulblets of Lilium sp. (Asiatic hybrid ‘Gran Paradiso’). The inoculated bulblets fared significantly better than the uninoculated ones in terms of all the growth variables, namely size, weight, shoot length, number of leaves and leaf area, and in P uptake. However, bulblets inoculated with different AM inocula had optimum growth at different P levels. Bulblets inoculated with indigenous mixed vesicular-arbuscular mycorrhiza species (VAM I) and Glomus intraradices isolate 2 (VAM III) showed the best growth and early flowering at available soil P of 13.6 ppm, whereas those inoculated with Glomus intraradices isolate 1 (VAM II) showed higher growth at 2.5 ppm available soil P. Amongst the three tested inocula, VAM I promoted maximum shoot length, bulblet size, and weight at 13.6 ppm P. The bulblets under this treatment also flowered earlier, nearly a month before the uninoculated control ones.  相似文献   

19.
The effect of gibberellic acid (GA3), supplied to dormant hyacinth bulbs of cultivars ‘Lady Derby’ and ‘L'Innocence’ by vacuum infiltration, on growth and flowering was investigated. Results showed that GA3 in all applied concentrations (50, 500, 1000 and 5000 mg/l) accelerated growth and flowering in both cultivars, after chilling for 42 days in a garden frame in natural conditions or chilled dry in cold storage at 5°C. Bulb infiltration with 10 mg/l AgNO3 resulted in the acceleration of flowering only in ‘L'Innocence’, but stimulated the growth of the inflorescence stalk and leaves in both cultivars regardless of the mode of chilling.The infiltration method was confirmed to be very promising.  相似文献   

20.
Pre-plant dips of the root portion, shoot portion or entire rooted cutting in ancymidol [α-cyclopropyl-α-(θ-methoxypheny)-5-pyrimidinemethanol] or daminozide [butanedioic acid mono (2,2-dimethylhydrazide)] reduced the height of chrysanthemum (Chrysanthemum × morifolium Ramat. ‘Garland’) regardless of the plant part treated. However, shoot and entire cutting dips were generally more effective than root dips. Height and dry weight decreased with increasing concentrations of both chemicals, and flowering was slightly delayed by ancymidol. Exposure time (length of dip) had no effect on subsequent height reduction. No phytotoxicity resulted from any dip treatment, although in one experiment, daminozide foliar sprays induced a change in flower color.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号