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1.
Abstract

Strawberry is an herbaceous perennial that can be easily propagated by stolons or by crown division. Seedlings have a few months in the juvenile period. The growth is determined with a terminal inflorescence as a modified stem or cyme. Flower induction is sensitive to thermo-photoperiod and to several agronomic and nutritional factors. The strawberry plant is highly adapted to diverse temperate climates and to production under forced artificial growing conditions. In the present study, a dynamic architectural model of growth is described and discussed in order to reveal strawberry development under different cultivation systems. The aim is to improve the cultural knowledge and understanding of the physiological control of axillary meristems, which can enhance the Strawberry fruit production.  相似文献   

2.
Summary

The Montana blue huckleberry (Vaccinium globulare Rydb.) is a popular and highly sought wild fruit in the western United States. Because it is becoming increasingly difficult to meet growing market demands from wild harvests, growers and state officials are funding projects to investigate cultivation of the fruit. This study investigates the vegetative and reproductive growth patterns of this species as a prelude to its cultivation. Such information is critical in properly scheduling fertilizing, pruning and other cultural practices. The species produces fixed sympodial, non-episodic vegetative extension growth over a four-week period each season, followed by apical abortion and the formation of vegetative or mixed buds. Floret differentiation begins shortly after cessation of shoot growth and all floral parts are differentiated by late summer of the year prior to anthesis.  相似文献   

3.
Abstract

Tomato ringspot virus (ToRSV) is an important disease of red raspberry which is vectored by the dagger nematode, Xiphinema americanum. A field study was conducted to evaluate crop rotation as an alternative to soil fumigation for the management of ToRSV. The effects of treatments on nematode population densities and ToRSV were evaluated for 18 months during growth of rotation crops, and for 36 months after replanting raspberries. Treatments included the rotational crops rapeseed (Brassica napus) and tall fescue (Festuca arundinacea) (nonhosts for ToRSV), clean fallow, fumigation with methyl bromide, and controls in which raspberries followed raspberries. At planting, X. americanum densities were highest in fescue and control plots and lowest in fumigated plots, but densities decreased and remained low in all plots after planting ‘Meeker’ raspberries. Raspberry leaves were collected in each plot and assayed for ToRSV with ELISA for 3 years. ToRSV was detected only in the control plots. Rotations with rapeseed or tall fescue, or weed-free fallow were as effective as fumigation with methyl bromide in preventing re-infection of raspberry plants with ToRSV for three years.  相似文献   

4.
Summary

Mature ‘Kotata’ trailing blackberry plants growing in the alternate-year (AY) system in the field, were treated with ammonium sulfate depleted in 15N in early April, 1997. Based on the whole plant, excluding roots, accumulation of new dry matter over the two year AY production cycle averaged 5.96 kg plant-1. On average, 28, 64 and 8% of this new dry-matter accumulation could be attributed to harvested fruit; loss from the crop as prunings and leaf senescence; and increased dry matter in the crowns for the next growth cycle, respectively. On average, 46% of new dry matter accumulation occurred in the off-year (non-producing). Whole plant (excluding roots) accumulation of new N (labelled and non-labelled) over the two-year AY production cycle averaged 63.7 g N plant” . Over a two-year production cycle, 44% of new N accumulation occurred in the off-year. Of the newly accumulated N, 37% was in harvested fruit, 58% was lost from the crop as prunings, and 5% was accumulated in crowns for the next growth cycle. For both the on-year and the off-year plants fertilized with labelled N, near maximum nitrogen derived from fertilizer (NDFF) accumulation occurred by August. At this time, 45% of the applied fertilizer could be accounted for in the non-root portion of on-year plants. A portion of this maximum on-year accumulation was either lost from the system or translocated to the roots. At the time of maximum accumulation, 39, 37,19, 3 and 2% of the accumulated NDFF was contained in the fruit, laterals, primocanes plus primocane leaves, floricanes, and crowns, respectively. Labelled N applied in the off-year was used primarily for primocane and primocane leaf growth. A large portion of the nitrogen stored in the off-year was used for early growth of floricanes, fruiting laterals and fruit in the following on-year. Excluding roots, by the end of the 1997 season, almost 30% of the applied fertilizer was accounted for in the non-root portion of off-year plants. There was also evidence of remobilization of N among plant tissues at different times during the production cycle. Results of this study suggest fertilizer N is an important N source for fruiting lateral and fruit growth in the on-year and for new primocane and primocane leaf growth in the off-year. N accumulated in the off-year is also an important source for early growth of floricanes, fruiting laterals and fruit the following year.  相似文献   

5.
Assessment of tree growth and yield components of Coffea arabica L. cv. Ruiru 11, as influenced by tree training on single or two-stem systems at densities between 1600-4800 trees per ha during the first production cycle was carried out at Ruiru, Kenya over three years. Trees trained on the two-stem system tended to be taller than those on singlestems. Although the results were not clear, trees at low plant densities had thicker stems irrespective of the training system. The total number of primary branches was significantly higher on trees trained on the two-stem system. However, bearing primaries and productive wood were higher on the single-stem system during the first year of production. The number of bearing primaries and productive wood increased in subsequent production years on the two-stem system. Training trees on the two-stem system significantly depressed yields in the first production year by 245 to 842%, irrespective of plant density. Yields of clean coffee increased significantly with tree density irrespective of the tree training method. Yields over the production period increased by 33, 45,27 and 9% with increases in planting densities from 1600 to 2400, 2400 to 3200, 3200 to 4000 and 4000 to 4800 trees per ha, respectively. However, yields increased at a decreasing rate at densities above 3200 trees per ha. The proportions of the large grade ‘A’ sized coffee beans were not significantly affected by the treatments. It was concluded that it is possible to raise two stems during the first production cycle of ‘Ruiru 11’, although this might not be economical. Single stems would be preferred and a high plant density of between 3200-4000 trees per ha would be optimum during the first coffee production cycle.  相似文献   

6.
Summary

Semi-hardwood cuttings of Cornus alba ‘Sibirica’, Deutzia ‘Mont Rose’, Forsythia × intermedia ‘Lynwood’, Ligustrum vulgare ‘Liga’, Philadelphus × virginalis, Potentilla fruticosa ‘Goldfinger’, and Spiraea × vanhouttei were planted on seven dates from July to October in two years and at three locations to investigate the effect of planting date on root formation, axillary bud growth, and plant survival. Cuttings were planted directly in the field and covered with polyethylene. Generally, root formation, bud growth, and plant survival were similar both years and at the three locations. All species except Deutzia had relatively constant rooting percentages at planting dates until mid August. For all species rooting percentages declined from mid August to October. Except for Deutzia, plant survival the following spring was constant or decreasing with planting date. For all species except Potentilla axillary bud growth and survival of cuttings planted in late September or October tended to increase while rooting percentages continued to decrease. In all species there was a close relationship between axillary bud growth and survival. Results revealed that many roots per cutting accelerated axillary bud growth.  相似文献   

7.
Assessing tree growth trends over time is a central but challenging aspect of urban forest management. The potential damage caused by invasive devices used in dendrochronological analysis is a common concern among urban foresters. Thus, the development of a less-invasive method for assessing tree growth rate faster that provides reliable results is clearly beneficial. In this study, resistance drilling (RD) profiles were compared with stem core assessments (Core) to estimate the growth rate of 78 trees of three species (Quercus robur, Ulmus procera, and Platanus x acerofolia). All studied trees were core-sampled in 2013 and then resistance drilled in 2015 at a stem height of 1–1.3 m in both north (N) and west axes (W). The dependency and accuracy of paired annual ring series (CORE measurements and Resi reading) were tested using ANOVA and regression analysis. In addition, point and event year tests were determined to confirm the accuracy of the RD to assess growth trends at both population and tree level. Growth series from both methods were cross-dated to test the reliability of RD to relate historical tree growth to past climatic conditions. ANOVA analysis confirmed that average ring width values and age of 70 out of 78 trees were statistically similar for both methods and similar for both sampled stem axes. Within each tree, regression analysis indicated significant correlation between cored ring datasets and paired resistance drilled ring datasets (R2 = 0.78–0.95, p < 0.05) across species. RD reliably detected pointer years at population level for Q. robur only. For all species, RD could not adequately detect event years at tree level. Regardless of species and drill axes, RD was less accurate in measuring ring width below 1 mm. For all species, RD yielded lower intercorrelation indices and greater number of “A” flagged segments as compared to CORE. Overall, RD can successfully estimate mean annual ring values to a comparable standard as conventional CORE analysis. However, the RD device used in this study did not detect the inter-annual growth pattern to the same standard as stem CORE analysis, RD should not be used to replace dendrochronology in climate-tree growth studies.  相似文献   

8.
ABSTRACT

Monthly above-ground destructive sampling and partitioning of the plant into distinct component parts for growth and nutrient element (N, P, K, Ca, Mg, Na, B, Cu, Zn, Fe and Mn) analyses were used to compare elemental compositions in two red raspberry (Rubus idaeus L.) cultivars (‘Willamette’ and ‘Haida’) grown in a uniformly managed field plot. Quantitative measurements showed that the two cultivars had different growth patterns. ‘Haida’ yielded greater fresh berry weight and dry matter content than ‘Willamette’ on a per floricane basis, but, because of fewer ‘Haida’ than ‘Willamette’ floricanes in the plot after standard commercial pruning practices, fresh berry yield was similar for both cultivars on a unit area basis. ‘Haida’ berries ripened slightly earlier than ‘Willamette’. Stem, lateral and leaf growth differed between the two cultivars. Although only whole above-ground accumulation (kg ha-1) of one (Ca) of the ten elements measured was different in the two cultivars, the amounts and patterns of all nutrients in the various plant components of floricanes and primocanes differed in significant ways. In some cases, element concentrations in a specific plant component differed between cultivars while dry matter accumulation differed in the opposite way resulting in the same total accumulation in the cane involved. In other cases, there was greater accumulation in one cane type (primocane vs. floricane) than the other such that there was similar accumulation of that element in the whole plant. For Ca, accumulation in primocanes was greater for ‘Willamette’ than ‘Haida’ whereas there was no difference of accumulation in floricanes which resulted in greater accumulation of Ca in the whole above-ground plant in ‘Willamette’. Maximum accumulation of the elements in floricanes occurred generally earlier in the growing season (July to September) than in primocanes (September to October), and these maxima were frequently at different times for the two cultivars, making comparisons of nutrient compositions in the two cultivars complex. Detailed sampling periodically over the growing season in combination with element analysis of these raspberry plant components as done in this study provided a better basis for comparing nutrients in raspberry cultivars than examining element concentrations of a specific plant component (e.g., leaves) sampled once during the growing season because patterns of nutrients over time in the cultivars differed.  相似文献   

9.
Summary

Defoliated shoots of cvs Alphonso, Dashehari, Totapari etc. (receptors), could be induced to flower within four weeks during the off-season by veneer grafting them to leafy shoots of the off-season flowering cv. Royal Special (donor) during the non-flowering season. Experiments on defoliating the donor and receptor shoots revealed the crucial dual role of the leaves in flowering. In the ‘floral cycle’, leaves from the donor promoted flowering, whereas leaves on the receptors, in the vegative phase, were inhibitory, and prevented graft-induction of the receptors. Thus, for graft induction, leafy donors and defoliation of receptors were essential. The inhibitory effect of the leaves on the receptors was localized and did not affect flowering of the donor shoots’ The similarity between these findings and those in the herbaceous, day-length sensitive species strengthens the view that flower formation is controlled in the same way in herbaceous and in woody perennial species. A minimum threshold of the floral stimulus appeared to be another requirement for an optimum flowering response. This was concluded from an experiment in which the leafy receptors were defoliated on different dates during the off-season flowering cycle. At the end of cycle, the defoliated receptors produced small panicles, and finally only vegetative shoots, probably indicating sub-threshold levels of the stimulus. Bud activity at the apex in the receptor was also an important pre-requisite for graft-induction. Some veneer-grafted scions which remained dormant during the flowering cycle of the donor and which sprouted much later after the completion of off-season flowering, ‘escaped’ the stimulus and invariably turned out to be vegetative. It is postulated that the cyclic synthesis of the floral stimulus in the leaves in an inductive cycle, and the gap between two such cycles, mainly decides the flowering behaviour of mango cultivars—biennial, annual and multiflowering. Two other requiremets are the absence of non-induced leaves and the synchronization of meristematic activity in the bud with the inductive cycle. Juvenile shoots from one to four year old seedlings could not be graft-induced—unlike the shoots from mature, six year old seeding trees. This juvenility effect continued into the second year when defoliation of the receptor shoots had no effect and failed to induce them to flower.  相似文献   

10.
Trunk diameter variation (TDV) is considered one of the most promising tools for automating the scheduling of fruit tree irrigation, and trunk growth rate (TGR) a possible indicator of TDV values. The use of TGR in commercial orchards is less common in olive trees than in other species, possibly because the influence of the environment, orchard age and the presence of developing fruit on the olive tree seasonal TGR pattern is poorly understood. In this study the trunk growth rate (TGR) seasonal progression was characterized in fully irrigated young olive trees during fruiting and non-fruiting years. In both years, at the beginning of the season, a period with an almost linear increase was found, mainly determined by temperature. In the non-fruiting year TGR remained almost constant after that initial increase, while during the fruiting year a significant decrease occurred at approximately 25 days, from values around 0.2 mm day−1 to values around 0.1 mm day−1. Since midday shoot water potentials were not affected, this variation was likely not produced by water stress conditions. In addition, the lack of relationship between trunk growth rate and air temperature indicated that the TGR decrease in the fruiting year was not determined either by air temperature. The period of decreasing TGR values, however, coincided with the time that the endocarp reached its maximum transverse area, a significant moment for fruit development which precedes pit hardening. These results suggest that the traditional period where regulated deficit irrigation is done, “the pit hardening”, may be indicated easier and more accurate for TGR decrease and endocarp expansion.  相似文献   

11.
Alpine strawberry (Fragaria vesca L.) was grown in hydroponics with the nutrient film technique, in order to evaluate the effects of four buffer concentrations (1.3, 1.6, 1.9, 2.2 mS cm−1) and two cultural cycles (summer-spring versus autumn-spring) in terms of growth, yield and fruit quality (dry and optical residues, sugars, acids, antioxidants, mineral composition). The longer summer-spring cycle gave a correspondingly higher yield than the autumn-spring one. The 1.3 mS cm−1 nutrient solution was the most effective in terms of overall and spring production. However, the autumn and winter yields were not affected by the buffer EC. Fruit quality did not change with the cultural cycle, but the berries harvested in the spring had higher vitamin C and sucrose content and lower nitrate content compared with berries picked up in the winter. Fruit quality was also improved when the nutrient solution concentration increased. From the productive point of view, the cultural cycle choice should be made considering that 71% of the yield of the more productive summer-spring cycle derived from the spring harvest. Moreover, as regards the nutrient solution strength, 1.3 mS cm−1 EC should be preferred during the spring season, whereas the 2.2 mS cm−1 EC proved to be best in the winter in terms of fruit quality.  相似文献   

12.
The knowledge of the rate at which trees grow in urban areas is an important aspect to consider as it can influence our quantification and valuation of the ecosystem services provided by an urban forest. This study investigates growth variations in diameter and height for four common urban tree species (Acer pseudoplatanus, Betula pendula, Fraxinus excelsior and Quercus robur) across five cities in Great Britain (GB) and how the typical radial growth of two of those species (F. excelsior and Q. robur) changes with climate. Dendrochronology was used to identify tree age and changes in ring width and diameter at breast height (DBH) and tree height were measured in-situ at the time of coring. Results indicate a substantial variation in the mean annual growth rates and the relationships between DBH and age or height and age of each species across different cities. However, the multiple factors affecting tree growth seem to influence different species in different ways, with for example A. pseudoplatanus trees showing overall the fastest growth in Peterborough but B. pendula ones showing the slowest. Precipitation and temperature had an effect on radial growth of F. excelsior and Q. robur trees in GB, but the strength and direction of influence varied with time of year, species and city. In particular, low precipitation at the start or during the growing season was found to be a significant factor limiting radial growth. A trend towards a reduction in ring width increment was therefore identified in hot and dry years, primarily in south-eastern cities but in other cities too. This highlights the risk that a changing climate may have on the growth and, consequently, on the ecosystem service provision of healthy urban trees.  相似文献   

13.
Summary

The phenology of wild stands of strawberry guava (Psidium cattleianum Sabine) was studied at 100, 480 and 720.m over 2 years in ReÂunion Island. The shoots bore flower buds at the basal nodes, and vegetative buds at the apical nodes. Trees produced vegetative growth from September to December, flowers from November to January and fruit from February to June. Shoot growth was earlier at 100 and 720.m the first year, but were synchronized in the second year. Flowering and fruiting were also earlier at 100.m. The intervals between shoot emergence and flowering, and flowering and fruit maturity were strongly related to temperature, with base temperatures of 5.58C and 2.68C, and heat units requirements of 675 and 2,5528C.d, respectively. The number of shoots, flowers and fruit per branch varied across sites and years, unrelated to temperature. However, production was significantly higher at 720.m. Production was much lower after a hurricane. Flowering (y) was related to shoot production per branch (x) (log(y)=111.33.log(x); r2.=.0.78), whereas the fruit set rate was highly variable between trees (26±100%). The number of fruits per branch (1±6) was possibly related to poor shoot growth or fruit set, but unrelated to the timing of the phenological events. It is expected that commercial orchards would be more productive than feral stands.  相似文献   

14.
A method has been developed for the large-scale propagation of lilies from callus cultures. Bulb scales, being available at all times, are an ideal source of explants. Callus was induced throughout the annual cycle of all the 12 Oriental hybrid cultivars tested, by treating the bulb scales with a combination of 5 μM BA and 5 μM 2,4-D. Once initiated, this callus grew vigorously on media lacking exogenous growth substances. Callus induction by BA and 2,4-D, and the subsequent growth of such callus in the absence of exogenous growth substances, occurs within a broad range of cultivars and species within the genus. The callus could be maintained on a medium lacking ammonium salts, but the maximum growth rate was obtained at 10 mM NH4NO3. At low (0.2 mM) or zero levels of NH4NO3, light as compared with darkness was inhibitory to growth.The callus maintained its capacity for organogenesis. Maximum production of plantlets was obtained in continuous light on agar medium with 0.5 μM NAA.Potentially, the successive use of liquid and agar cultures can produce 6 × 1012 plants per year from 1 g (dry wt.) of callus. Plantlets derived from callus were consistently diploid and could be readily transferred to soil.  相似文献   

15.
Abstract

Micropropagation techniques are important for clonal multiplication, germplasm improvement, and gene conservation of three commercially cultivated and medicinally important Vaccinium species: cranberries, blueberries, and lingonberries. The in vitro propagation of Vaccinium species using axillary bud proliferation and adventitious shoot regeneration has been investigated in a number of previous studies. The morphogenesis seems to be highly dependent on plant growth regulators and media used for culture, which is again genotype specific. This review presents the progress in-depth of various aspects of Vaccinium propagation in vitro for its commercial production. It also discusses the issues that still need to be addressed to utilize the full potential of plant tissue culture techniques in mass propagation of Vaccinium species.  相似文献   

16.
Abstract

It is generally thought that olives (Olea europaea) require several days (over 80 days) of chilling temperatures (7.2°C) for flower induction; minimum nighttime temperatures of 2-4°C and maximum daytime temperature of 15.5-19°C are considered optimum for flower and fruit production. Environmental chamber studies were conducted on potted olive trees for the purpose of defining flowering conditions for ‘Arbequina’. We repeatedly observed that good flower and fruit production in ‘Arbequina’ can be achieved even when the plants are not subjected to “chilling” temperatures or any chilling criteria that had previously been described necessary for flower and fruit production in olives. This phenomenon could be of great practical value because the results obtained can be exploited to cultivate olives in subtropical climates (e.g., southern and coastal Texas) where typical “chilling” temperatures are not commonly observed for prolonged periods of time.  相似文献   

17.
Summary

Beneh (Pistacia mutica F. & M.) and kolkhong (Pistacia khinjuk Stock) are wild species of pistachio which grow naturally with other trees in some parts of Iran. Because of their adaptibility to severe environmental conditions and their resistance to some pests and diseases, they can be used as rootstocks for pistachio cultivars. Poor germination and very low seedling vigour of these two species have been a major problem in using them as rootstocks for pistachio cultivars. In this study gibberellic acid (GA3), at five concentrations (100, 250, 500, 750 and 1000 mg l21), were used during and after stratification to enhance seedling growth. The results showed that GA3, applied during and after stratification, significantly increased the length, trunk diameter, internode length, leaf area and fresh and dry weight of seedlings of both beneh and kolkhong species. However, application of GA3 after stratification was more effective on seedling growth of beneh. GA3 applied at higher concentrations (500 and 750 mg l21) increased the rate of growth, but growth malformations were clearly evident in seedlings of kolkhong. GA3 at 250 mg l21 enhanced seedlings growth of kolkhong. It was concluded that application of GA3 to the seedlings might be a useful method for promoting rapid shoot growth of beneh and kolkhong and reduce the expense of seedling production in glasshouse conditions.  相似文献   

18.
Summary

Short-day (SD) and long-day (LD) photoperiodic treatments were compared, at equal light integral, for their effects on the seedling growth of four bedding plant species: geranium, impatiens, pansy and petunia. Total leaf area was frequently increased by LD given either by day-extension lighting or night-break lighting, but this response was inconsistent and varied greatly between species and experiments. In contrast, leaf greenness measured using a SPAD-502 meter, a measure of chlorophyll content per unit area of leaf, was consistently and significantly increased in LD in all four species. However, night-break lighting may have been somewhat less effective than day-extension lighting. Increasing the day-extension lighting from 16 h to 24 h gave no further intensification of greenness. Consistent with increases in leaf greenness, total dry weight was generally increased in LD, and increases were of a similar magnitude to those given by doubling the daily light integral. The promotional effect of LD on chlorophyll content appears to have been largely ignored or overlooked in recent years, but this may be because simple methods for measuring ‘greenness’ have only recently become widely available.  相似文献   

19.
为了提升草莓生产后期果实品质，通过叶面喷施不同浓度（0.5、1.0、1.5 mmol/L）硅酸钠，研究草莓生长后期植株长势以及果实硬度、品质和产量的变化情况。结果表明：喷施1.0 mmol/L硅酸钠处理效果最好，生长指标、品质指标和产量指标均表现较好，且抑制了植株徒长，与CK相比较，草莓株高显著降低11.1%，茎粗显著增加15%；喷施后10 d新叶叶绿素生长量增大80%，果实硬度变化幅度增加6%;8成熟、9成熟、10成熟果实硬度分别显著提高65.9%、81.5%、86.8%，果实糖度分别增加8.70%、3.17%、10.77%；平均单果质量、行产量、测产行产量分别增加2.8%、12.9%、8.0%，畸形果率则降低3.6百分点。建议在草莓结果后期酌情使用。  相似文献   

20.
Summary

Paclobutrazol was applied, with or without mefluidide, to the grassed alleyways between the bare soil tree lines in a bush cider orchard cv Michelin. The chemical not only suppressed grass growth but, in the year following application, produced typical paclobutrazol effects on the trees in adjacent rows including a reduction in growth.  相似文献   

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