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.
Investigations were undertaken to explore the possibility of improving setting, retention and weight of fruits in ‘Early Seedless’ and ‘Calcuttia’ cultivars of lichi (Litchi chinensis) by means of growth regulators. Indole acetic acid (IAA) at 20, 40 and 80 mg l?1, 2,4-dichlorophenoxy acetic acid (2,4-D) at 2,4 and 8 mg l?1 and gibberellic acid (GA3) at 50, 100 and 150 mg l?1 were sprayed on panicles in the first fortnight of April, when 50–100% flowers had opened. All 3 growth regulators caused a favourable effect on fruit setting, fruit retention and weight of individual fruits, but IAA at 20 mg l?1 proved the best for enhancing setting, GA3 at 50 mg l?1 for increasing retention and GA3 at 100 mg l?1 for improving fruit weight. IAA and GA3 should, therefore, be used in combination. Between the 2 cultivars tested, ‘Calcuttia’ proved superior to ‘Early Seedless’ in fruit setting, fruit retention and weight of individual fruits.  相似文献   

2.
The effect of GA3 15 mg l?1, Planofix (NAA = 1-naphthalene acetic acid) 300 mg l?1 and Ethrel 250 mg l?1 on granulation and fruit quality in ‘Kaula’ mandarin (Citrus recticulata Blanco) was studied during 1975–1976. Three sprays of Planofix reduced the incidence of granulation to 30.7% from 62.7% in control. Three sprays of GA3 were almost equally effective (31.3% granulation). These treatments also improved the fruit quality and gave the highest fruit weight, pulp percentage, juice, T.S.S., reducing and non-reducing sugars and ascorbic acid, and the lowest acidity, peel and rag. In both these treatments (3 sprays of GA3 or Planofix) the T.S.S. was 9.3% (8.1% in control). The application of 3 sprays of Planofix 300 mg l?1 or GA3 15 mg l?1 is, therefore, considered to be successful in reducing the granulation in this cultivar of mandarin.  相似文献   

3.
Soaking of bulbs in 3 concentrations of indoleacetic acid (IAA), gibberellic acid (GA3), 2-chloroethyltrimethyl ammonium chloride (cycocel) or 2-chloroethylphosphonic acid (ethrel) showed various responses on growth and flowering. IAA increased the weight and number of bulblets, GA3 increased bulb weight. Cycocel (1000 mg l?1) increased the number of flowers, while GA3 increased the diameter of the flowers.Application of IAA at 100 mg l?1 and GA3 at 10, 100 or 1000 mg l?1 twice as foliar spray at an interval of 30 days promoted the number of bulblets on the treated plants, while high concentrations of cycocel and ethrel (1000 mg l?1) increased the weight of bulblets. All concentrations of IAA, GA3 and 1000 mg l?1 cycocel increased the number and size of the flowers.  相似文献   

4.
Application of 2,4-D and 2,4,5-T at concentrations ranging from 5 to 20 mg l?1 to 5-year-old ‘Pant Lemon-1’ (Citrus limon Burm) trees reduced the vegetative growth in terms of height, spread, shoot length, number and size of the leaves in the autumn flush. Various NAA treatments (5–20 mg l?1), however, enhanced growth, but not to the extent that was observed after GA3 treatments. Application of GA3 at 10–40 mg l?1 significantly enhanced all aspects of growth, and the effects were most pronounced at 20 and 40 mg l?1. Nutritional status of the leaves showed a slight variation in relation to vegetative growth under various treatments.Some 2,4-D- and 2,4,5-T-treatments increased the fruit yield over the control, which could suggest mobilization of foods even at the expense of reduced vegetative growth. On the other hand, NAA, particularly at 10 mg l?1, increased both vegetative growth and yield, suggesting that the transport of the photosynthates from the leaves to the fruits was not at the expense of new growth extension. Due to excessive growth enhancement under higher concentrations of GA3 (20 and 40 mg l?1), comparatively fewer nutrients were translocated to the fruit “sinks”, thereby resulting in a non-significant decrease in yield.  相似文献   

5.
Summary

Different concentrations of aminoethoxyvinylglycine (AVG) and gibberellic acid (GA3) and their combinations, applied at two stages of fruit growth, were evaluated for prolonging the marketing season of `Feicheng' peaches. GA3 applied at the end of pit hardening, or AVG applied two weeks before commercial harvest, inhibited fruit maturation on the tree, delayed harvest and reduced flesh browning after cold storage in a concentration-dependent manner. A synergistic effect was found when both GA3 and AVG were used, with the combination of 100 or 150.mg l±1 GA3, applied at the end of pit hardening, and 100 mg l±1 AVG, applied two weeks before harvest giving the best results. These combinations retarded the change in ground colour, loss of firmness, and reduction in acidity by 2±3 weeks. Since harvest was prolonged by 2±3 weeks, soluble solids content (SSC) in fruit increased compared with the control (harvested earlier). Fruit size was significantly greater on treated trees compared with the controls when fruit set was controlled to the same level by hand thinning. After four weeks of storage and 4.d at 208C, 83% of control fruit developed tissue browning, but only 5% of AVG + GA3-treated fruit developed browning after six weeks of storage and 4 d at 208C. Thus, the marketing season of `Feicheng' peaches was prolonged by at least four weeks by 100 or 150 mg l±1 of GA3 and 100 mg l±1 of AVG. Fruit treated with 150 mg l±1 GA3 plus 100 to 150 mg l±1 AVG showed similar results but failed to ripen properly after cold storage.  相似文献   

6.
‘St. Julien A’ (Prunus instititia L.) rootstock was induced to proliferate shoots on a modified half-strength Murashige and Skoog (MS) medium. Cultures treated with 12.5 mg l?1 gibberellic acid (GA3) produced elongated shoots suitable for rooting. Elongated shoots were placed in media with indolebutyric acid (IBA) or indole-3-acetic acid (IAA) with or without a 16-day dark incubation. Light (16-h photoperiod) inhibited rooting. IAA (4 mg l?1) was ineffective in promoting rooting. Rooting was best when shoots were incubated in the dark with IBA (4 mg l?1). GA3 was deleterious to shoots, causing chlorosis and apical die-back. Light regime interacted with auxin treatments in affecting shoot condition. Shoot condition was better on shoots treated with IBA and dark-incubated; while those treated with IAA were better when light-incubated.  相似文献   

7.
A single GA3-spray at petal-fall to the entire tree enhanced initial set in the ‘Navelate’ sweet orange (Citrus sinensis L. Osbeck), but this effect was transient and in most cases final yield was not increased. When followed by girdling, final yield was increased even in the most productive orchards, this effect being due to an increase in fruit number while fruit size was unaffected. The response was markedly dependent on the GA3 concentration, 5 mg l?1 giving the best results. Higher concentrations up to 20 mg l?1 even reduced yield compared to the untreated control trees. Chlormequat reduced the number of fruits finally cropped without affecting their size, an effect which may be explained through a reduction in the endogenous gibberellin levels.  相似文献   

8.
Field grown day-neutral, June-bearing and everbearing strawberry cultivars responded similarly to GA3 in most cases. GA3 stimulated daughter-plant production in ‘Hecker’ (DN) and suppressed it in ‘Guardian’ (June). Fifty mg l?1 GA3 increased initial runner production of all cultivars, while both 50 and 100 mg l?1 GA3 increased fruit yield the year following treatment. In greenhouse studies, GA3 initially increased leaf number, petiole length and runner production, but the effects diminished with time. Phthalimide at 1000 mg l?1 was most effective in increasing leaf number.  相似文献   

9.
A study on the effect of maleic hydrazide (MH) on vegetative growth, flowering and yield of bottle gourd (Lagenaria siceraria (Mol) Standl.) was conducted during the rainy and summer seasons of 1979 and 1980, respectively. MH at 150 mg l?1 stimulated the elongation of the main shoot, while MH at 50 mg l?1 induced more branches per plant. Staminate flowers appeared late and at the lowest node number in control plants, whereas MH at 150 mg l?1 had a profound effect on the earliest appearance of pistillate flowers at the lowest node number. Male: female ratio was lowered with MH at 50 mg l?1 and was most effective in producing the maximum number of fruits and fruit weight per plant and ultimately the yield. GA3, NAA and ethrel did not influence yield, while MH did.  相似文献   

10.
Gibberellic acid (GA3, 10000 mg 1?1) acted as an androecide for bell pepper, Capsicum annuum L., when sprayed at the onset of flowering and after an interval of 10 days. Parthenocarpic fruits were produced, but seeds could be obtained by hand-pollination. The technique can be used to produce hybrid seed and also to obtain high quality seedless fruits.  相似文献   

11.
Ether-soluble extracts from malformed panicles showed 2 malformin-like substances when assayed by mung bean growth test. Three malformin-like substances were found on the chromatograms using the maize root curvature test. Developing malformed panicles were sprayed 3 times with 2240 mg l?1 glutathione or 2110 mg l?1 ascorbic acid. Panicles thus treated appeared healthy 15 days after treatment and produced the same number of fruits as healthy panicles.  相似文献   

12.
《Scientia Horticulturae》1986,28(4):323-329
Sambucus caerulea (elder) seeds did not germinate after 4°C cool treatments for up to 30 days, when monitored for a further 30 days at 21°C. When seeds were soaked for 24 h in gibberellic acid (GA3) prior to and during cold treatment, germination percentage depended on GA3 concentration and duration of cold treatment. The highest germination percentage was 55 (1000 mg l−1 GA3 for 30 days at 4°C). When seeds were treated with ethephon at 0, 100 or 1000 mg l−1, no germination was recorded after a subsequent 30-day 4°C treatment. Ethephon added to GA3 gave a strong interaction, leading to further promotion in germination. Optimal germination was obtained after 1000 mg l−1 GA3 and 100 mg l−1 ethephon for 30 days at 4°C (69%).The addition of ethanol, acetone, dimethyl sulfoxide or polyethylene glycol to the GA3 soak as infusion agents either reduced or did not change the germination percentage.  相似文献   

13.
The nucellus and globular adventitious proembryos were removed from 2-month-old fruits of mango (Mangifera indica L.) cultivars ‘Ono’ and ‘Chino’, and were cultured on sterile, solid Murashige and Skoog (MS) medium that had been modified as follows: half-strength major salts and chelated iron; 20% (v/v) coconut water (CW); 6% sucrose; 100 mg l?1 ascorbic acid and 400 mg l?1 glutamine. Embryogenic explants were sub-cultured after 4–6 weeks in liquid modified MS medium containing 2 mg l?1 2,4-dichlorophenoxyacetic acid (2,4-D) instead of CW. Rapidly growing cultures were established and were sub-cultured monthly. Somatic embryogenesis was induced following sub-culture from MS medium with 2,4-D to MS without growth regulators and with or without activated charcoal (0.5%). Germination of somatic embryos appeared to be enhanced by 1 mg l?1 benzyladenine (BA); however, most of the germinating embryos became embryogenic.  相似文献   

14.
In attempts to reduce the glasshouse period of fully-cooled 5°C-forced tulips, ‘Apeldoorn’ bulbs were soaked before planting in aerated and non-aerated gibberellic acid (GA3) solutions for 2–48 h. A 48-h treatment with 250–500 mg l?1 GA3 was the most effective, giving a glasshouse period 7–11 days shorter than for untreated bulbs. Soaks for 24 and 48 h caused root emergence, and 48-h soaks caused perianth segment splitting in one experiment. Aerated or non-aerated GA3 solutions gave similar results. Soaking in water alone gave a smaller increase in earliness. In general, a shortened glasshouse period was associated with shorter whole stem and last internode lengths. In GA3 treatments, flower losses were lower than for distilled water treated and untreated bulbs. A practical treatment would be a non-aerated soak for 24 h with between 250 and 500 mg l?1 GA3.  相似文献   

15.
Bal  Erdinc  Torçuk  Ali İzzet  Özer  Cengiz 《Erwerbs-Obstbau》2022,64(2):127-133

The study was carried out to determine the effect of melatonin on quality and postharvest life of sweet cherries (Prunus avium L.) cv. ‘Sweetheart’ during storage. The fruits were dipped at different concentrations of melatonin (0, 250, 500 and 1000?µmol l?1 for 10?min) and distilled water as control. The changes of sweet cherries were assessed at 7?day intervals by evaluating the following quality parameters: firmness, soluble solids content, titratable acidity, respiration rate, color values (L* and chroma), ascorbic acid content, total anthocyanin content, total phenolic content, and antioxidant activity. The results showed that increasing the dose to 1000?µmol l?1 melatonin had a remarkable effect on maintaining the quality of sweet cherry. 1000?µmol l?1 and 500?µmol l?1 melatonin treatments significantly inhibited the decrease in firmness, ascorbic acid, total phenols, total anthocyanin, antioxidant content and reduced color changes and respiration rate. However, the total soluble solids content and titratable acidity of the fruit were not influenced by melatonin applications. These findings indicate that melatonin treatment may be effective in maintaining quality and bioactive compounds of sweet cherry fruit.

  相似文献   

16.
This study evaluates the effect of gibberellic acid (GA3) in inducing parthenocarpy in ‘Algerie’ loquat, as well as the optimum treatment conditions and associated techniques, hand thinning and ringing, to produce seedless fruit with high enough quality for fresh consumption. GA3 applied in the course of the phenological growth stages 504–508 of the BBCH-scale produced seedless fruits, with the magnitude of the response depending on the concentration applied and number of treatments. Percentage of panicles bearing seedless fruitlets significantly increased with increasing GA3 concentrations up to 100 mg l−1 and significantly and positively correlated with the number of treatments applied. Trees treated three times with 100 mg l−1 developed more than 90% of panicles bearing almost 7 seedless fruits per panicle, which were smaller in size, drier and slightly acid but similar in TSS concentration and skin colour than seeded fruits from untreated trees. Fruit thinning to 3 fruits per panicle did not increase seedless fruit size, but ringing performed at the onset of cell enlargement stage, growth stage 702 of the BBCH-scale, significantly increased fruit size by 12–15%, depending on the year. Trees treated three times with 100 mg l−1 of GA3 and ringed produced 26 kg, on average, of seeded fruit of suitable commercial quality.  相似文献   

17.
Sprays with 250–2000 mg l?1 propyl 3-t-butylphenoxy acetate (MB 25,105) and 250 and 500 mg l?1 GA4+7 + 6-benzyladenine (Promalin) were applied to scion growth of first nursery trees of ‘Bartlett’ pear (Pyrus communis L.), ‘Bing’ cherry (Prunus avium L.) and ‘Oregon Spur II Delicious’ apple (Malus domestica Borkh.) to stimulate lateral branching in the nursery. Most treatments significantly increased branching compared to untreated controls. Combination sprays of the two chemicals were usually better than either used alone. Chemical treatment usually produced greater branching and wider branch angles than mechanical heading. Both chemical and mechanical treatments reduced tree height and caliper, but the decrease was not always statistically significant.  相似文献   

18.
Oxidative browning is one of the reasons why Protea cynaroides is not being extensively propagated via tissue culture techniques. The reduction of oxidative browning was best achieved by stirring the explants for 1 h in an antioxidant solution mixture containing 100 mg l−1 ascorbic acid and 1500 mg l−1 citric acid before inserting them into the medium. In combination with this antioxidant solution, in vitro establishment was highly successful where 100% bud growth was achieved by explants growing under 16 h photoperiod.  相似文献   

19.
Summary

Meristems of ginger with or without leaf primordia were induced to form shoots on three-quarter strength Murashige-Skoog’s (MS) medium containing sucrose 6%, coconut milk (CM) 20%, ascorbic acid (AA) 100 mg l?1, glutamine (GL) 400 mg l?1, activated charcoal (AC) 250 mg l?1, 6-benzylaminopurine (BAP) 0.5 mg l?1, indolebutyric acid (IBA) 0.4 mg l?1 and agar 0.8%. Meristem-derived shoots exhibited consistent multiplication on three-quarter strength MS medium containing sucrose (3%), AA (100 mg l?1), AC (100 mg l?1), BAP (4–5 mg l?1) and agar (0.8%). Liquid media (agitated or static) were less effective than a solid (agar-gelled) medium for micropropagation. Kinetin and naphthalene acetic acid (NAA) incorporated at various levels (0.01–0.8 mg l?1) with or without added BAP and IBA neither improved plantlet formation nor enhanced shoot multiplication. The in vitro plants were successfully established in vivo and the rhizome yield was comparable with that of plants grown by conventional methods.  相似文献   

20.
Summary

The effects of a post-harvest application of gibberellic acid (GA3) at various concentrations (0, 10, 25, 50, or 100 mg l–1) and for different periods of incubation (1, 2, or 3 h) on the breaking of dormancy and on sprouting in potato (Solanum tuberosum L., cv. Marfona) minitubers of two ages (freshly-harvested or 1 week after harvest) were investigated. Compared with untreated, control minitubers, GA3-treated minitubers showed a significantly shorter period of dormancy (46 d), especially when the minitubers were treated at all concentrations immediately after harvest (41 d). GA3 treatment had a greater effect on dormancy in freshly-harvested minitubers than in 1 week-old minitubers, probably because of the reduced uptake of GA3 solution after skin-set. At lower concentrations of GA3, the period of dormancy tended to decrease the longer the minitubers were immersed in the GA3 solution. In contrast, at higher concentrations of GA3, the duration of immersion only had an effect up to 2 h and any longer immersion was ineffective. The average number of sprouts was not affected by GA3 concentration, or by the time of incubation, but was significantly higher for freshly-harvested minitubers (1.4) than for 1 week-old minitubers (1.2). The lengths of the sprouts increased with an increase in GA3 concentration, especially in freshly-harvested minitubers. Consequently, immersing freshly-harvested potato minitubers in a low concentration of GA3 (up to 25 mg l–1) for up to 3 h effectively shortened the period of dormancy and led to the formation of sprouts of optimum length.  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