荔枝环剥时期对新梢生长及碳素储备的影响

 枝梢环剥显著抑制了‘怀枝’荔枝新梢的生长，并导致射线细胞和髓部大量积累淀粉。梢芽萌发或伸长前环剥可完全抑制新梢生长，而新梢快速伸长期环剥对其抑制效应最弱。秋季环剥对新梢的抑制和对淀粉积累的促进效应明显高于春季环剥。环剥口以上的老叶面积和环剥位置并不影响环剥对新梢生长的抑制效应和促进淀粉的积累效应，但环剥口以上单位枝梢长度的叶面积与淀粉含量呈显著正相关。     

Effect of Hydrogen Cyanamide on Vegetative Growth,Yield, and Fruit Quality of Fig cv. Zidi in a Warm Production Area

The fig tree (Ficus carica L.) is widely cultivated in the Mediterranean region under warm climates. Fig yield is governed by the previous crop load and is strongly dependent on shoot length. Special cultural practices are required to stimulate new vegetative growth that will ensure regular and high productivity. The present study focused on the use of the rest breaking agent hydrogen cyanamide (HC) as Dormex to enhance vegetative growth, which influences the yield. A field trial was held in northern Tunisia (36° 49′ N; 9° 48′ E) on mature fig trees cv. Zidi. In reference to untreated trees as control, two hydrogen cyanamide treatments at 1% and 1.5% HC were considered. Bud break rate, vegetative growth, starch content of shoots, yield, and fruit characteristics were assessed. Results indicated that 1.5% HC significantly increased shoot length, fruit number per shoot, and yield. It advanced bud break by 10 days and fruit ripening by 7 days compared to the control. However, leaf number, leaf area, and starch content seem to be unaffected by hydrogen cyanamide treatments. Regarding fruit quality, a 1.5% HC dose significantly increased dry matter content, while fruit diameter and total soluble solids remain unaffected. In conclusion, hydrogen cyanamide could be used under warm conditions to improve vegetative growth of fig trees cv. Zidi and consequently fig productivity. Application of 1.5% HC 40 days before bud break was the most effective in increasing shoot length and yield.     

Effect of Time of Application of Fertilizer Nitrogen on the Growth,Flower Development and Fruit Set of Maiden Apple Trees,Var. Lord Lambourne,and on the Distribution of Total Nitrogen Within the Trees

Fertilizer nitrogen was applied to pot-grown trees during the year of initial scion growth either as “spring N”, “summer N” or “autumn N”, while other trees were left untreated—“minus N”. Tree performance was followed until fruit set the following summer.

At regular intervals whole trees were sampled, divided into as many as seven different parts, which were separately weighed, dried and analysed for total nitrogen. Specimens were also taken for histological examination of flower bud development.

The large amount of fertilizer given as “spring N” resulted in extensive root damage from which the trees did not recover fully; nevertheless they produced large, vigorous scions. After “spring N” and “summer N” at lower dosages the total N content of all parts increased substantially and rapidly. “Autumn N” was absorbed more slowly and remained largely in the roots during the winter, when a considerable amount of root growth took place.

Flowers were initiated in late July or early August on all trees except those given “spring N”, on which flower primordia were not initiated until September. The development of flower buds was accelerated during September on “summer N” trees compared with those left untreated. From the end of November until the end of March no further differentiation took place on “minus N” or “spring N” trees, but it continued on the other treatments, especially following “autumn N”.

“Summer N” and “autumn N” trees were 4–5 days in advance of the others in flowering. “Summer N” trees had large flowers and large green primary leaves, whereas those on “autumn N” trees were smaller and the leaves were initially pale, though turning dark green during blossoming.

When the blossoms were self-pollinated under controlled conditions virtually no fruit was set on “minus N” and “spring N” trees, but “summer N” gave an appreciable set and “autumn N” a heavy set. Only the “summer N” and ”autumn N” flowers had ovules that remained viable six days after anthesis, which was the minimum period found necessary for the pollen tubes to effect fertilization.

It is suggested that fertilizer nitrogen stimulates the synthesis of a kinin-like factor in the roots and that the difference in response to applications at different times of year depends upon the stage of development of the flower buds when this factor reaches them.     

Comparison of sampling strategies for determining fruit mineral concentrations in ‘Hass’ avocado (Persea americana Mill.)

Summary

Spatial and temporal variation in mineral and dry matter (DM: % dry weight) concentrations were examined in ‘Hass’ avocado (Persea americana Mill.) fruit to identify sampling strategies for examining fruit mineral, DM and fruit quality relationships. Calcium (Ca), magnesium (Mg), potassium (K), and DM concentrations were compared from different parts of the same fruit, from fruit harvested from different shoot types and locations within the same tree, and at different stages during the growing season, from fruit set to commercial harvest. The main source of variation within fruit was longitudinal, with K and DM concentrations being higher at the distal end of the fruit. Sampling methods based on equatorial plugs of tissue provided the best estimates of whole fruit values for DM and mineral nutrients. While there was much variability in the internal distribution of minerals within the fruit, the distribution was the same for fruit from both the northern and southern aspects of the tree. During the first 4 months after fruit set, fruit from determinate floral shoots (i.e., with a flower in the terminal position) had higher Ca and Mg concentrations than fruit from indeterminate shoots (i.e., with a shoot in the terminal position). After this time, fruit Mg and Ca concentrations were higher on indeterminate shoots, possibly because of changes in sink-strength and increased transpirational flow associated with new leaf growth on indeterminate shoots. The data showed that shoot type was a source of fruit-tofruit variability in an avocado crop, and that care should be taken in sampling fruit tissues for nutrient analyses.     

不同施氮水平纽荷尔脐橙叶绿素含量的季节变化

以1年生盆栽枳砧纽荷尔脐橙为试材,研究不同施氮水平对叶片氮含量,春梢、夏梢和秋梢落叶率,以及春梢、夏梢和秋梢叶绿素含量季节变化的影响。结果显示,施氮植株当年萌发的春梢和夏梢的落叶率在次年5月有减少的趋势,秋梢落叶率则有增加的趋势,其余时期施氮量与落叶率关系不明显;叶片氮含量与施氮量极显著正相关(r=0.97);施氮在大多数时期可显著或极显著提高不同枝梢叶片的叶绿素含量,在整个测定时期内保持较为稳定,在单株施氮量6.5g范围内这种效应随施氮量增加而显著增强,对照(不施氮)植株不同枝梢叶片的叶绿素含量从当年10月开始明显下降且次年4月锐降。由此可见,充足的氮肥不仅可提高纽荷尔脐橙叶片叶绿素含量且可减少其季节性变化幅度。     

广州地区澳洲坚果抽梢与坐果的关系

广州地区澳洲坚果一年主要抽生三次梢,以多年生枝和春梢为主要结果母枝,分别占43.1%和39.1%.结果能力以更梢母枝最强,平均每枝坐果3.0个,其次为多年生枝(2.0个).平均花坐果率0.22%.坐果数与结果母枝长度、粗度、粗/长比和叶片数无显著相关,与花序数和初始坐果数密切相关(R~2=0.7653).树冠郁闭条件极显著地减少初始坐果数.花后5周内落掉总花量的99%以上.幼果的另一个脱落高峰在花后第5至8周,主要是旺盛营养生长与迅速生长的果实的营养竞争所致.     

Regulated deficit irrigation in ‘Clementina de Nules’ citrus trees. II: Vegetative growth

Summary

An experiment on Regulated Deficit Irrigation (RDI) was performed during 1995 and 1996 in an orchard planted with drip-irrigated ‘Clementina de Nules’/Carrizo Citrange in Moncada (Valencia) Spain. Treatments consisted of a control, irrigated during the whole year at 125% ET_lys and RDI treatments where irrigation was reduced to 25% or to 50% of crop evapotranspiration measured by a weighing lysimeter (ET_lys) during one of the following periods: I) flowering and fruit set (spring); II) initial fruit enlargement phase (summer) and III) final fruit growth and maturation phases (end of summer-autumn). An additional treatment, denominated 50%-Year, was irrigated at 50% ET_lys during the whole year. The effects of RDI treatments in relation to tree water status (pre-dawn Ψ^pd and midday Ψ^md leaf water potential, as well as their integral with time) show a good relation between total shoot emergence in the different growth flushes and the stress intensity reached (Ψ^pd) (r² = 0.80). This correlation was mainly due to the number of floral shoots (r² = 0.86) and not to vegetative ones (r² = 0.22). Similar results were observed between the stress integral at pre-dawn in each period and the former sprouting variables. In all cases, correlation was better with pre-dawn leaf water potential or with pre-dawn stress integral than with those at midday. RDI during spring reduced shoot length of the first growth flush (A1) and increased fruitlet fall after restarting normal irrigation. It also produced “off-season” flowering in the second flush growth (A2) and increased shoot emergence of the third flush growth (A3) with about 10% of them being floral. Summer RDI treatments did not alter vegetative growth, and although they produced off-season flowering (A3) it was much smaller than that of autumn RDI treatments, which in addition reduced vegetative growth with respect to the control. These effects, together with those of yield and fruit quality presented elsewhere, show that summer is the more appropriate period to apply RDI in “Clementina de Nules” mandarin trees.     

萝卜花芽分化过程中茎尖和叶片碳水化合物含量的变化

 以萝卜冬性品种‘一点红’和春性品种‘短叶13’为材料，研究花芽分化过程中茎尖和叶片以及萌动种子碳水化合物含量的变化。萌动种子在5℃下处理20 d，然后在温暖(>15℃)、长日照(16h)下生长，于不同花芽分化时期测定可溶性总糖、蔗糖和淀粉含量。结果表明：在花芽分化期间，无论是茎尖或是叶片，可溶性总糖、蔗糖和淀粉含量的变化趋势在两个品种之间较为接近。随着花芽分化的继续，可溶性总糖含量呈先上升后下降的趋势；蔗糖和淀粉含量则一直呈现上升趋势，在花芽分化完成后再下降。叶片中可溶性总糖、蔗糖和淀粉含量始终低于茎尖。冬性品种的蔗糖和淀粉含量在整个花芽分化期间始终较低，但在花芽分化初期的可溶性总糖含量则高于春性品种。     

苹果叶片营养分析适宜采样时期研究

在渭北高原以盛果期“红富士”苹果树为采样对象,在幼果速长期、春梢停长期、花芽分化期、果实采前膨大期、果实采收期定位采集叶片,分析叶片中的氮、磷、钾、钙含量,以确定合理的叶分析采样时期.结果表明:从幼果速长期到果实采收期,叶片中氮、磷含量持续降低,钾为“反抛物线”,钙为持续升高.通过对不同生长期叶片营养元素含量分析,认为花芽分化期为测定叶片氮、磷、钙的适宜采样时期,钾应在果实采收期或春梢停长期采样分析较为合理.     

Light penetration,growth, and fruit productivity in ‘Fuji’ apple trees trained to four growing systems

The study was conducted to document the range in soil nutrients, trunk and shoot growth, leaf characteristics and nutrient content, flower bud characteristics, yield, fruit quality, disease occurrence, light penetration, and shoot bark color in a 15-year-old ‘Fuji’ apple (Malus × domestica Borkh.) orchard on M.26 rootstocks trained to four growing systems. SS trees naturally growing had greater width and volume than the LT lightly heading, MLT heavily heading, and S trees thinning and bending. LT trees had more upward terminal shoots at old branches, large numbers of lateral shoots, and longer total shoot length. Leaf [N], [P], and [K] were the lowest for the MLT trees. SS and S trees had greater flower bud density and fruit yield, but LT trees had poor fruit color and less soluble solids and firmness. Percent light penetration into the canopy was the highest with the S system but not different from MLT or SS. The lowest was for the LT system, however, it was not statistically different from MLT or SS.     

Seasonal Changes of Shoot Carbohydrates and Growth Characteristics of ‘Trakya İlkeren’ Grape Variety (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.)

This research was conducted to determine the changes in the seasonal carbohydrates of annual shoots and growth characteristics of 10 years old ‘Trakya ?lkeren’ grape variety. Grapevines are grafted on 5BB and 5C rootstocks and they were grown in heavy clay soil conditions. In the study, changes of sugar, starch and total carbohydrates were determined from bud burst to dormancy. While sugar, starch and total carbohydrates showed significant differences (P < 0.01) there were no differences between rootstocks. Although sugar, starch and total carbohydrates of shoots decreased from bud burst to blooming, they increased thereafter until vegetative growth stopped. Total carbohydrates of annual shoots have been found to accumulate in period from blooming to harvest. Total and mean leaf area, shoot length and diameter, total chlorophyll and chlorophyll a/b ratio showed significantly variation among rootstocks and phenological stages (P < 0.01). Whereas the highest chlorophyll contents were found in the blooming, it was found at the lowest through to harvest. Overall mean and total leaf area, shoot length and shoot diameter, total chlorophyll content and chlorophyll a/b ratio were significantly higher on 5BB grafted vines. In the study, 5BB rootstocks are found suitable in terms of shoot carbohydrate accumulation and growth characteristics for ‘Trakya ?lkeren’ grape variety.     

蜡梅枝芽特性的研究

蜡梅的腋芽为复芽，由主芽和副芽上下叠生构成，副芽由枝隙薄壁细胞群经反分化形成的芽原基发育而来，可形成多级副芽，副芽一般为叶芽，多处于休眠状态，枝的更新有赖于副芽，蜡梅具有顶梢自枯习性，假二叉分枝，枝条一年多次生长，春梢加长生长主要在四月（扬州），时间短，速度快。花芽分化与新梢生长密切相关，春梢加长生长减缓时正是春梢花芽集中开始分化期。蜡梅的雏梢和未木质化枝条、花（果）梗截面为四棱形，是由于形成层和其外侧4个具有有限分生能力维管束活动叠加的结果。     

枇杷属野生植物生长结果习性观察

对华南农业大学园艺学院枇杷属（Eriobotrya Lind.l）植物种质资源圃内种植保存的野生枇杷生长结果习性进行观察,结果表明：依照章恢志简明分类法属于＂春季开花的枇杷属植物＂春、夏、秋梢多为2次抽完,冬梢1次抽完;＂秋冬季开花的枇杷属植物＂春、冬梢多只抽发1次,夏、秋梢多抽发2次。偶有3次抽发现象,如野生的普通枇杷的夏梢,南亚枇杷窄叶变型的春梢。同种的不同植株抽梢有不同步现象,不同年份抽梢情况也有差异,受气候环境条件影响大。同种的不同植株开花习性差异大,如台湾枇杷由潮安地区引种与由海南地区引种,花期明显不同。由此认为,《中国果树志.龙眼枇杷卷》按花期对野生枇杷属植物进行分类的方法值得商榷。野生枇杷坐果率低,多数种果实的鲜食价值不大。     

Effects of fruit load on flower bud initiation and development in peach

Summary

This study aims to quantify the effects of fruit crop-load on flowering and to determine the relationships between flowering and phloem sap carbohydrate and nitrogen content fractions from budding to dormancy in ‘Zincal 5’ nectarine. Fruit load significantly reduced the number of flowers per tree both indirectly, by reducing the number of shoots per tree and the number of nodes per shoot, and directly, by reducing the number of floral buds per node. The intensity of the response depended on the number of fruits developed per tree. Trees that kept all fruits up to senescence flowered 35% less than trees thinned by hand to 40% of fruits at pit hardening, and 55% less than trees completely thinned in bloom by hand. Trees that kept all fruits had significantly lower glucose and sorbitol contents in the phloem sap of mixed branches up to harvest date and full vegetative growth, respectively, but no significant relationships were found between the concentrations of these carbohydrates and flowering intensity in the following Spring. Sucrose and fructose did not show any significant difference in regard to crop-load. In fibrous roots, starch content was not related to fruit load up to dormancy, indicating that starch content is not associated with flower bud induction and differentiation. The nitrate-nitrogen fraction was significantly higher, and the ammonium-nitrogen fraction was significantly lower, in trees that tended to flower less, suggesting some disturbance in nitrate reduction in these trees.     

苹果幼树铜、镉分布特征与累积规律研究

 以3年生盆栽苹果(红富士/平邑甜茶) 为试材, 土壤施入重金属铜(Cu) 和镉(Cd) 后,于生长季不同时期检测根、枝、叶内铜、镉的含量变化。结果表明, 苹果根系、新梢和叶片中Cu和Cd累积量都随着土壤Cu和Cd施入量的增加而增大。从春梢展叶开始, 根系和新梢Cu、Cd含量逐渐增加, 到春梢停长时达到最高, 之后下降; 叶片Cu、Cd含量变化比根系和新梢滞后, 到秋梢生长期才达到最高。Cu、Cd在不同器官的累积量由高到低为: 根系>枝干>新梢>叶片; 苹果根系吸收和积累Cu的能力大于Cd, 但Cd向地上部的迁移能力大于Cu。     

‘糯米糍’荔枝碳素营养储备动态与坐果的关系

 以10～12年生的‘糯米糍’荔枝(Litchi chinensis Sonn. ) 为材料, 研究了高产树(60～65 kg·株^{- 1} ) 和低产树(5～10 kg·株^{- 1} ) 不同部位(叶片、各级枝条和主干) 碳素营养储备(淀粉) 的差异及季节动态; 分析了不同果实发育阶段树体碳素营养水平与坐果率的关系。结果表明, 果实成熟时高产树各部位的淀粉含量均低于低产树, 而可溶性糖含量高于低产树。果实采收后, 低产树早于高产树抽发新梢。入冬季前(11月底前) , 低产树和高产树分别抽发了3次和2次秋梢。7～11月秋梢生长发育期间, 高产树和低产树均无显著淀粉积累, 11月中旬以后枝梢生长停滞期间, 各部位, 尤其是4 cm直径以内的枝条大量积累淀粉, 在花穗发育前达到高峰。之后, 随花穗发育、开花及坐果而持续降低。高产树和低产树各部位淀粉高峰并无明显差异, 表明坐果量对树体碳素营养储备的累积并无明显的长期影响。叶片、主枝和主干积累的淀粉含量较低, 总体相对稳定; 而4 cm直径以下的枝梢淀粉含量变化剧烈, 说明这些枝梢是更为活跃的碳素储备库。本研究还表明, 坐果早期(花后3周内) 枝条(2 cm直径) 的淀粉含量与该枝条上最终坐果率呈显著正相关, 而果实发育中期(花后8周) 枝条淀粉含量与坐果率无关, 说明早期果实发 育一定程度依赖树体碳素营养储备, 而中后期果实发育几乎不依赖树体储备。     

Stärkeeinlagerung in die Blütenorgane beim Apfel vom Beginn der Blütenknospendifferenzierung bis zur Aufblüte

Starch as an important reserve carbohydrate plays in deciduous fruit species an important role in frost resistance of the wood during winter as well as of flowers during spring frosts. Also during development of flowers the deposition of starch, e.g. in the conducting tissue of the style and in pollen grains is evident. This starch accumulation in the reproductive flower parts seems to be important for fertilization and thus fruit set. The investigations presented should contribute to elucidate the dynamic of starch accumulation in the different organs of a flower bud in apple, from the beginning of bud differentiation until anthesis. The sampled buds were sectioned after embedding in plastic material. Starch accumulation was determined by image analysis. In the four apple cultivars ‘Boskoop’, ‘Elstar’, ‘Golden Delicious’ and ‘Pinova’ starch deposition could be observed already shortly after beginning of flower bud differentiation in July/August in the calyx, corolla, anthers and ovary. Until autumn, starch content increased considerably, it showed during winter some fluctuations according to flower organ, and decreased again towards the flowering season, presumately by conversion to sucrose, as shown in the wood in relation to frost resistance. This decrease seems to be related to the energy demand which is needed for flower development, fertilization and early fruit development.     

不同施肥措施对蓝莓植株生长及果实品质的影响

对伯克利蓝莓生长的3个关键期即发芽前、初夏、秋季时,施用3种肥料即硫酸铵、磷酸二铵、氮磷钾复合肥,每株按3个不同的施肥总量即25g、50g、100g进行搭配施肥试验,研究对蓝莓植株生长与果实品质的影响。结果表明,以施用NPK复合肥每株50g,分春夏秋3次分施时,蓝莓的株高、冠幅、新梢长度等生长状况,单果重、单株产量,果实的可溶性固形物含量、有机酸含量、Vc含量等品质指标均最佳。     

早钟6号枇杷顶生枝的成花特征

在"早钟6号"枇杷Eriobotrya japonica(Thunb.) Lindl.顶生枝的成花期间,调查其上第一次夏梢顶芽成花时分化出的叶片数量,跟踪顶生枝上两种特异芽体的发育去向,观察顶生枝上4种不同形态顶芽的成花特征.结果表明:第一次夏梢顶芽成花的临界节位超过16节或27节,即第一次夏梢的顶芽先后分化的叶片、小雏叶和鳞片叶数达到16片或27片以上时,生长点即可进入花芽形态分化.观察到两种特异芽体最终成为花芽的结果,同时还观察到4种不同形态的顶芽在成花解剖特征方面存在一定差异,初步确定4种不同形态的顶芽与成花进程之间的对应关系.     

苹果新根生理生化特性研究

以盆栽３年生新红星／怀来海棠（Ｍａｌｕｓｍｉｃｒｏｍａｌｕｓ）为试材，研究了生长根和吸收根的还原能力、碳氮物质代谢、吲哚乙酸氧化酶（ＩＯＤ）、过氧化物酶（ＰＯＤ）和超氧化物歧化酶（ＳＯＤ）的周年动态变化。结果表明，两类新根均于春、夏、秋形成３次吸收高峰，但还原能力的高峰只于夏秋季出现，其中夏季高峰最大；淀粉、糖、蛋白质含量及ＩＯＤ、ＰＯＤ活性随新梢旺长而降低，随新梢缓慢或停止生长而积累，氨基酸含量、ＳＯＤ活性相反；吸收根的吸收能力、淀粉、糖、蛋白质含量、ＰＯＤ、ＩＯＤ活性均显著高于生长根，但吸收根中氨基酸含量、ＳＯＤ活性却小于生长根，因而两类新根的代谢特点和功能不同，其发生数量和比例影响树势和植株的生长发育