破眠剂1号对葡萄冬芽休眠解除及萌芽过程中呼吸代谢的影响

以中需冷量葡萄品种‘夏黑’为试材,采用呼吸抑制剂法、借助氧电极,研究破眠剂1号解除葡萄冬芽自然休眠及促进萌芽过程中芽呼吸代谢的变化。结果表明:破眠剂1号处理葡萄休眠冬芽比对照萌发早、整齐,且萌芽率显著高于对照;破眠剂1号处理前期(休眠解除期)暂时抑制葡萄冬芽的总呼吸速率,后期(萌芽准备期)促进葡萄冬芽总呼吸速率迅速上升,并显著高于对照。破眠剂1号处理前期暂时抑制葡萄休眠冬芽的三羧酸循环和细胞色素途径的运行活性,激活磷酸戊糖途径和交替途径的运行活性,从而促进自然休眠的解除;处理后期抑制磷酸戊糖途径和交替途径的运行活性,促进三羧酸循环和细胞色素途径的运行活性,促进葡萄冬芽的萌发。综上所述,破眠剂1号可代替葡萄冬芽的部分需冷量,使其自然休眠解除并促进萌芽,冷量不足则阻碍这一过程。     

温度对果树自然休眠调控的影响

植物只有满足一定的需冷量才能解除休眠,不同的植物对低温需求量不同,落叶果树设施栽培,打破自然休眠至关重要。在过去30多年里,对休眠解除措施的研究主要集中在化学破眠剂方面,并且取得较好的效果,但其他措施尤其是物理破眠技术研究较少。目前应用的化学破眠剂如硫脲和6-BA等都对人体有害,生产上更需要无公害的破眠措施,而物理破眠措施正适应了这一要求。1温度对解除树体休眠过程的影响一定程度的低温可解除落叶果树休眠,不同的树种其需冷量不同。低温对解除休眠的作用是逐渐累积的,不同的温度,其低温效果不同,而且依不同树种而异;此外,温…     

日光温室葡萄当年二次结果试验

葡萄具有多次结果习性。我们在日光温室条件下，采用“V”形架整形，合理密植和修剪，适时进行石灰氮处理打破冬芽休眠，促进花芽分化和芽眼萌发等措施，实现了日光温室葡萄当年二次结果。试验总结如下：     

大蒜在果树上的应用

大蒜在果树上的应用一、促进萌芽：在塑料大棚中栽培葡萄，涂抹蒜汁可打破葡萄休眠，提前萌芽７－１０天；葡萄修剪后，立即用蒜汁涂抹伤口，可防止剪口干枯，并可促进第一芽萌发整齐；为使葡萄结果母枝基部的芽萌发，可在基部刻伤后涂抹蒜汁，效果胜似涂抹抽枝宝。二、防...     

提早解除葡萄休眠的药剂筛选试验

在葡萄设施栽培中,除了必要的栽培管理技术外,何时升温也是非常重要的,过早升温可能造成萌芽不整齐、花芽分化不良等情况,过晚升温又抢不上市场那么何时升温才是最佳时期?理论上,在温度等条件满足的条件下,升温的最佳时期是在自然休眠结束时。自然状态下解除休眠需满足其需冷量。目前适合于温室栽培的品种的需冷量,按尤他模型计算基本为1060-1810需冷单位[l,2],按O-7.2℃计算法计算需冷量为600~1 600hls〕。若想提早设施葡萄的上市时间,应通过选用低需冷量品种、休眠过程中增加有效低温量、提早打破树体休眠3个途径来实现。本试验选用了几…     

日光温室草莓高效促成栽培

日光温室草莓促成栽培是指在自然条件下,完成花芽分化后,刚要进入休眠之前就开始采取保温等措施,使其不进入休眠,让植株正常生长,提早现蕾、开花和结果的栽培方式。可使草莓提早到12月上旬陆续上市,经济效益十分可观。     

早黑宝葡萄设施栽培关键技术

在葡萄设施栽培实践中，常常出现葡萄隔年结果、不能连续丰产而导致葡萄设施栽培失败。为解决这一问题，许多研究者采用采果后除膜、及时进行更新修剪促使葡萄二次萌发新梢，从而保证葡萄产量的技术措施。但对早黑宝葡萄来说，采用这些措施，会使树体逐年衰弱，产量得不到保证，为此，我们连续6a（年）进行了试验研究，在明确了设施条件下光合特性和花芽分化规律的基础上，总结出配套的设施栽培技术，使早黑宝葡萄连续4a（年）667m^2（亩）产控制在1500k～2000kg。     

落叶果树芽休眠调控研究进展

在自然条件下 ,温带落叶果树为了适应冬季的低温 ,芽在外表上停止生长的现象 ,称为芽的休眠。休眠是一个十分复杂的现象 ,关于落叶果树芽的休眠及其调控机理 ,目前人们还不清楚。随着近年来设施栽培面积的不断增大 ,休眠问题成为研究领域的一个热点 ,并已取得了很大进展。1　芽休眠的分类　　迄今为止 ,休眠的分类尚未规范化 ,根据不同的标准 ,可将其划分为不同的种类和休眠阶段。1 1　按照芽休眠的生理活性划分　a 自然休眠(naturaldormancyorspontaneousdormancy) ,是指即使给予适宜生长的外部环境条件芽仍不能萌发生长 ,而需要经过一定的…     

保护地果树怎样进行强制休眠

通过采取人为措施 ,提前或延长果树休眠期 ,从而实现果树的促成或延迟栽培。常用的强制休眠方法有 :1　制造阴冷环境　人工制造不适宜树体萌发生长的环境 ,延长其休眠期 ,从而实现延迟栽培。如对冬枣 ,于 4月份春暖花开前 ,在大棚上遮盖草帘、棚内放置冰块强制树体继续休眠 ,延     

几种化学药剂对破除葡萄与桃自然休眠的效果

以桃、葡萄为试材,探讨多种化学药剂和外源生长调节剂打破休眠的效应。结果表明:CaCN2打破葡萄的休眠效果稳定,可使萌芽提早6～17d,并提高萌芽率,其破眠效果随需冷量的增加而显著;几种化学药剂在桃树上应用,其打破休眠的效果差异较大,CaCN2、NH4NO3对打破桃休眠无效,硫脲的破眠效果最明显,可使叶芽萌发提前9～12d、花芽6d,并提高萌芽率;KNO3对破除休眠亦有一定效果。外源生长调节剂对休眠的调节作用因调节剂种类、浓度和使用时间而异:Ze(50mg/L)+GA3(100mg/L)可完全打破叶芽的休眠,100mg/L6-BA对尚未完成自然休眠的花芽萌发有明显的促进作用,IAA和2,4-D却对芽的萌发表现出强烈的抑制作用。     

韭菜叶片生长动态和分蘖、抽薹特性

对 3个休眠韭菜品种和 9个不休眠韭菜品种叶片生长动态、分蘖和抽薹特性的研究表明 ,在全年不收割条件下 ,韭菜单株年生长叶片 41.2 2～ 47.0 3片 ,叶片平均叶龄 39.33～ 44 .87d。新叶生长高峰在 5～ 8月 ,叶片平均间隔 5 .39～ 8.0 3d ,叶片平均日生长量 1.6 6～ 1.84cm ,5～ 8月是全年单株生长最高的时期 ,株高 41.30～5 0 .2 3cm。韭菜单株年分蘖 4～ 5个 ,全年有两次分蘖高峰 ,第 1次在 5～ 6月 ,第 2次在 9～ 10月 ,但以第 1次分蘖为主。韭菜不休眠品种抽薹期长而分散 ,为 37.0 0～ 6 5 .33d ,休眠品种抽薹期短而集中 ,为 15 .0 0～ 30 .6 7d ,休眠品种全年生长期 2 82～ 2 92d ,不休眠品种全年生长期为 32 0～ 32 3d。     

Veränderte Temperaturbedingungen als Folge des Klimawandels und ihre Bedeutung für den Erdbeer- und Himbeeranbau

The importance of the predicted temperature increase as a consequence of change in climate on strawberry and raspberry production is discussed with regard to flower initiation, dormancy and temperature optimum for photosynthesis on the basis of a literature review and temperature data from the location of Geisenheim, Germany. June-bearing strawberry and biennial fruiting raspberry cultivars and remontant cultivars for both species are considered. In the future, problems will be expected for flower initiation of June-bearing raspberry and for breaking of dormancy of strawberry and raspberry cultivars with high chilling requirement. The predicted temperature increase will lead to early flowering and cropping of the berries.     

Characteristics of Dormancy of June-Bearing Strawberry(Fragaria Xananassa Duch. cv. Elsanta)

Abstract

The development of Fragaria xananassa Duch. cv. Elsanta was analyzed during summer and fall in order to define the sequence of growth alteration and dormancy with regard to inflorescence initiation. The leaf growth as well as the initiation of the inflorescence buds were followed in the fall by conditions imposed in a climate chamber, with plants then being transfered to conditions favorable for growth. Results pointed to clear changes in leaf growth characteristics over the late summer-early fall (September-October) period while the leaf emergence rate remained constant up to mid-October when it stopped. The first sign of inflorescence initiation started in early October, and the differentiation of the terminal flower reached the stamen initiation stage within 2 weeks. From early November, the terminal flower had initiated the carpel primordia and no further differentiation was detected later on. The plant growth potential, expressed by the size, at full growth, of the leaf or inflorescence axis emerging from the terminal bud, decreased progressively from early September and reached a minimum between October and November. By mid-December, the growth capacity of the plant was restored to a situation similar to that described for early September.     

Flowering in pyrethrum (Tanacetum cinerariaefolium L.). II. Changes in plant growth regulator concentrations

Radioimmunoassays were used to quantify the endogenous concentrations of plant growth regulators (PGRs) in pyrethrum during flower initiation and development. The concentrations of gibberellins, abscisic acid, indole acetic acid, zeatin and zeatin riboside, dihydrozeatin and dihydrozeatin riboside, and isopentenyladenine and isopentyladenosine were assayed. Fluctuations in PGR concentrations were correlated with flower bud initiation, flower stem elongation and floral differentiation. The gibberellin concentration increased during vernalization (6°C night temperature), a treatment known to promote floral initiation. A marked increase in gibberellin concentration was correlated with the onset of flower stem elongation. The concentration of the auxin indole acetic acid declined significantly at this time and remained low during flower bud development. Low photon flux density conditions, which retard floral initiation in otherwise inductive vernalizing conditions, failed to induce a decrease in indole acetic acid concentration.     

High temperatures and time to budbreak in low chill apricot ‘Palsteyn’. Towards a better understanding of chill and heat requirements fulfilment

The efficiency of different temperature cycles in inducing budburst of one-year-old shoots of the apricot cultivar ‘Palsteyn’ from dormancy was evaluated. Three replications of shoots were collected during two consecutive years from adult trees, following the accumulation of different amounts of chilling in the field. Thereafter, shoots were exposed to different temperature cycles in growth chambers, for 60 days. The temperature treatments included a continuous temperature of 5 °C; daily temperature cycles of 19/5 h at 5/15 °C, at 5/20 °C, and at 5/25 °C; and the same temperature cycles for the remainder of the 60-day period, after pretreatment at 5 °C for 30 or 45 days. After the temperature treatments, shoots were forced at 25 °C until budburst. The mean time to budburst (MTB) (in days) of lateral vegetative, terminal vegetative and reproductive buds was evaluated. The efficiency of the different treatments was greatly influenced by the date on which shoots were cut. High temperatures had a more positive effect on the reduction of MTB when chilling accumulation had occurred in the field instead of the growth chamber. After partial chilling accumulation in the field, high temperatures (25 °C) combined with low temperatures are more efficient than cycles of moderate temperatures (15 or 20 °C) to induce an earlier budburst. In view of these results, a parallel accumulation of both chilling and heat requirements after partial chilling accumulation is suggested. The application of these results could assist in the development of more accurate models for the prediction of the overcoming of dormancy and blooming.     

Study of some factors affecting the growth and development of myoga (Zingiber mioga Roscoe)

In order to optimise production of the edible flower buds produced by myoga (Zingiber mioga Roscoe) a greater understanding of the growth and development of the plant and factors influencing flower initiation and development are required. The vegetative growth phase in myoga was characterised by a distinct period of pseudostem development from the planted rhizome piece followed by an extended period of rhizome growth from both the base of pseudostems and the planted rhizome piece. The transition from pseudostem formation to the initiation of rhizome growth occurred at the same time as the dry weight of the planted rhizome piece ceased to decline. Flower bud initiation and development occurred over an extended period, beginning soon after the commencement of new rhizome growth and ending prior to foliage senescence. Flower buds were observed at the terminal meristem of first, second, third and fourth order rhizomes. Increasing temperatures stimulated both increased vegetative growth and flower bud initiation and development. Low flower bud yields recorded under conditions of low temperature were the result of reduced rate of floral initiation and not abortion of flower buds. Increased shading of plants grown under glasshouse conditions resulted in reduced flower bud yield and similarly the response resulted from decreased initiation rather than abortion.     

Synchronization of anthesis and enhancement of vegetative growth in coffee (Coffea arabica L.) following water stress during floral initiation

SUMMARY

The possibility of using water stress during floral initiation and development, to synchronize flowering in potted coffee trees of cvs Catuai Rojo and Mundo Novo was investigated. Moderate and severe cyclic and constant water stress had little effect on vegetative growth during floral initiation. However, upon rewatering, shoot growth was significantly greater in plants where leaf water potential [¨,] had declined to -2.5 MPa compared with plants where ¨, was maintained above -0.5 MPa. The period of floral initiation was not influenced by water stress and occurred only under short days (<12 h). In contrast, a y, of -2.5 MPa significantly reduced the number of inflorescences compared with plants maintained at a ¨| of -0.5 or -1.5 MPa. This reduction was associated with leaf drop in stressed plants. Therefore, regular irrigation during the period of floral initiation is recommended. Water stress (¨, of -1.5 or -2.5 MPa compared with -0.5 MPa) accelerated floral development with no deleterious effects on floral differentiation. Once flower buds are fully differentiated they enter dormancy and reach anthesis only if trees are stressed and rewa-tered. Flower buds remain dormant if trees are watered regularly or a constant water stress provided. A constant period of water stress in the late stages of floral development after floral initiation is complete provides a means of increasing the proportion of fully differentiated dormant flower buds (mature buds). This could represent a practical method to achieve synchronized flowering in field conditions where there is irrigation and a reliable dry season in the late stages of floral development.     

Physiology of flowering and dormancy regulation in annual- and biennial-fruiting red raspberry (Rubus idaeus L.) – a review

Summary

Recent research on how the structure and physiological development of red raspberry (Rubus idaeus L.) plants are controlled by genotype and the climatic environment is reviewed. Some older work, especially on plant structure relations, is also included. Physiological differences between annual- and biennial-fruiting plant types are highlighted. One major difference is the different requirements for flower formation. While biennial-fruiting cultivars have an absolute low temperature (≤ approx. 15°C) requirement for floral initiation, annual-fruiting cultivars readily initiate floral primordia at temperatures as high as a constant 30°C. Also, while biennial-fruiting cultivars are facultative short-day plants with a critical photoperiod of 15 h at intermediate temperatures, flowering is promoted by long photoperiods in at least some annual-fruiting cultivars. However, the essential difference that determines whether the shoot life-cycle becomes annual or biennial is that, in biennial-fruiting genotypes, floral initiation is linked to the induction of bud dormancy; whereas, in annual-fruiting cultivars, floral initiation is followed by direct flower development. Although this is genetically determined, it is a plastic trait that is subject to modification by the environment. Thus, at low temperatures and under short photoperiods, the majority of initiated buds also enter dormancy in annual-fruiting cultivars, with tip-flowering as a result. Practical applications are discussed, and it is concluded that our present physiological knowledge-base provides excellent opportunities for the manipulation of raspberry crops for out-of-season production and high yields. It also provides a firm platform for further exploration of the underlying molecular genetics of plant structures and response mechanisms.     

半秋眠和非秋眠紫花苜蓿在华北地区生长适应性评价

以来自国内外50个半秋眠和非秋眠紫花苜蓿品种为研究对象,从农艺性状、营养价值和产量几方面作了分析.首先通过相关性分析表明:秋季植株再生高度与秋眠等级显著相关,以再生高度为标准将50个苜蓿品种分为4组,分析组间农艺性状差异,进一步对产量和营养价值作了分析,筛选出适合当地种植的优良品种.