氮、磷、钾不同用量对圆葱干物质积累及产量的影响

在宁夏中部干旱区以圆葱"巴顿"品种为试材,研究了氮、磷、钾配施不同用量对圆葱干物质积累和产量的影响。结果表明:氮15kg/667m2、磷17.5kg/667m2、钾25kg/667m2(T1)处理对圆葱株高、叶片数、生长量有明显地促进作用,鳞茎产量5 580.83kg/667m2,较当地常规施肥氮10kg/667m2、磷12.5kg/667m2、钾20kg/667m2处理(CK)产量4 478.93kg/667m2,增产24.6%;氮20kg/667m2、磷22.5kg/667m2、钾30kg/667m2处理(T2)产量4 702.09kg/667m2,较CK增产4.98%,较T1减产15.75%;进而优化得出"巴顿"丰产高效的合理施肥模式为氮15kg/667m2、磷17.5kg/667m2、钾20kg/667m2,为当地圆葱大田栽培合理施肥提供参考和技术指导。     

线辣椒新品种青线椒1 号

青线椒1 号是青海省农林科学院园艺研究所利
用当地主栽品种循化线辣椒优系99- 3- 5 与线辣椒
997- 1 杂交选育而成。2007 年进行品种比较试验,青
线椒1 号每667 m2 产量达到1 733.1 kg,比对照循化
线辣椒增产12.96 %。2008～2009 年同期开展区域试
验和生产试验,区域试验中青线椒1 号每667 m2 平
均产量1 575.7 kg,比对照增产12.68 %;生产试验中
青线椒1 号每667 m2 平均产量为1 519.1 kg,比对照
增产11.41 %。2009 年12 月青线椒1 号通过青海省
农作物品种审定委员会审定。该品种从2009 年开始
进行示范推广,在青海省循化、贵德、尖扎、乐都等地
区累计推广面积已经超过100 hm2。     

华南型黄瓜品种比较试验

作者以青岛地区黄瓜主栽品种玉龙为对照,对山东省青岛市农业科学研究院黄瓜课题组新选育的3个华南型黄瓜组合进行了品比试验。试验结果表明,各参试黄瓜品种的生育期差异不大,瓜条均为白绿色短圆筒形,心腔均较小;2013C661在单瓜重(204.06 g)、产量(前期产量1 161.46 kg/667 m2,总产量7 099.14 kg/667 m2)、抗病性、风味品质等方面均优于玉龙(ck),建议可在青岛地区推广种植;2013C699风味虽不及玉龙(ck),但单瓜重(182.96 g)、产量(前期产量1 196.09 kg/667 m2,总产量6 847.72 kg/667 m2)、抗病性均较好,亦具有推广潜力。     

BGA土壤调理剂对木薯生长、产量及品质的影响

以木薯品种‘南植199’为试验材料,研究不同用量BGA土壤调理剂对木薯生长、产量及品质的影响。结果表明:施用280 kg/667 m2的BGA土壤调理剂和BGA 120 kg/667 m2与复合肥(15-15-15)27 kg/667 m2混施2种方式,均能有效促进木薯植株生长,显著提高鲜薯产量;BGA 120 kg/667 m2与复合肥(15-15-15)27 kg/667 m2混施,对木薯干物率和淀粉含量提高有显著效果。综合木薯生长情况、产量和品质等综合性状,以BGA 120 kg/667 m2与复合肥(15-15-15)27 kg/667 m2混施效果最佳。     

蒿菜-青玉米/小辣椒高效种植模式

<正>江苏省启东市是粮、棉、油、菜多元多熟制种植地区,精耕细作、集约化经营特点突出。近年来,启东市农技部门紧紧围绕农业增效、农民增收的农村工作方针,通过试验示范形成多种高效种植模式,提高了复种指数和经济效益,其中蒿菜-青玉米/小辣椒种植模式已在全市大面积推广,经济效益显著。1产量与效益蒿菜667m2产量5000kg,青玉米果穗667m2产量800kg,小辣椒(鲜椒)667m2产量655kg,年667m2产值3550元,667m2效益2500元。     

不同量氮肥对关苍术生育性状和产量性状的影响

以吉林地区关苍术为试材,设5个施肥量处理水平,即5kg/667m2(N1)、10kg/667m2(N2)、15kg/667m2(N3)、20kg/667m2(N4)、25kg/667m2(N5),以不施肥为对照,研究施用不同量氮肥对关苍术生育性状和产量性状的影响,探讨有利于关苍术高产的最佳施肥量。结果表明:施肥与不施肥比较,关苍术产量、质量有很大提高,不同施肥量对产量的影响达到显著或极显著的差异水平;最佳的施氮量为15kg/667m2(N3)。     

稻茬稻草覆盖栽培秋马铃薯技术模式与效益研究

试验和调查结果表明:(1)‘渝马铃薯1号’、‘中薯3号’、‘南中552’、‘川芋4号’等品种为稻草覆盖秋马铃薯优选品种。(2)秋马铃薯的最佳覆盖物为稻草,稻草全覆盖最佳用量为1000～1300kg/667m2。(3)稻草全覆盖栽培秋马铃薯,采用密度9000～11000窝/667m2、尿素10～15kg/667m2、氯化钾15kg/667m2的栽培组合可获得较高产量。(4)稻茬稻草覆盖栽培秋马铃薯以净作产量最高,667m2平均产量可达1236.9kg;不同间套作模式马铃薯产量高低顺序为"马铃薯/油菜">"马铃薯/秋菜">"马铃薯/榨菜"。(5)稻茬秋马铃薯纯收益间套作高于净作,高低顺序为"马铃薯/榨菜">"马铃薯/秋菜">"马铃薯/油菜">马铃薯净作,表明稻茬秋马铃薯间套作栽培十分有利于农民增收。     

马铃薯不同施肥量对产量的影响

为了进一步探索复合肥不同施用量对马铃薯品种"盘薯1号"产量的影响,通过"盘薯1号"的不同施肥量试验,寻求合理的施肥量,达到合理施肥,经济用肥的目的。试验结果表明:施肥量为30kg/667m2、40kg/667m2、60kg/667m2的产量较高,且差异不显著,与施肥量70kg的产量差异显著。说明该区域、该品种比较合理的667m2施肥量为30~40kg,随着施肥量的增加,产量反而有下降的趋势。     

炸片专用马铃薯新品种青薯6号

青薯 6号马铃薯是以固 33 -1为母本,以 92 -9 -44(73-21-1×Desiree)为父本,通过有性杂交选育而成。炸片试验结果色泽和酥脆性接近对照大西洋,符合炸片品种的各项指标。2005年 1月 10日通过青海省农作物品种审定委员会审定,定名为青薯 6号。1　产量1995年配制杂交组合,并从实生苗中筛选出优良单株。1996~1999年进行无性系繁殖和测产, 1 ~4代无性系平均产量为 2 659. 68kg· (667m2 )-1。2003、2004年同时进行区域试验和生产试验,区域试验平均产量为 2 138. 0kg·(667m2 )-1,比对照大西洋增产 50. 45 %,生产试验平均产量为 2 682. 6kg…     

氮肥施用量对喀斯特山区莴笋产量及经济效益的影响

为优化莴笋氮肥用量,为莴笋高产栽培提供参考,通过大田试验研究不同氮肥施用量对喀斯特山区莴笋产量及经济效益的影响。试验结果表明,在本试验条件下,无氮区(处理1)莴笋产量最低,仅991.7 kg/667 m2,随着氮肥用量的增加,莴笋产量显著提高,70%优化氮区(处理2)产量1 245.9 kg/667 m2,优化氮区(处理3)产量1 408.4 kg/667 m2,130%过量氮肥水平(处理4)产量最高,为1 579.2 kg/667 m2,且处理4纯收入、投入产出比、氮肥利用率均最高。     

The effect of various nitrogen fertilization and foliar nutrition regimes on the concentrations of sugars,carotenoids and phenolic compounds in carrot (Daucus carota L.)

The aim of this research was to determine the influence of various forms, diverse doses, and dates of application of nitrogen fertilizers and foliar nutrition on the concentration of sugars, carotenoids and phenolics compound in carrot. Two field experiments (Experiment I in 2003–2005 and Experiment II in 2004–2005) with carrot ‘Kazan F₁’ were conducted in Trzciana (50°06′N; 21°85′E) in Poland. Both experiments were arranged in a split-plot design with four replications. Two sub-blocks were identified in both experiments: sub-block (A) without foliar nutrition and sub-block (B) with plant foliar nutrition. In sub-block (B), plants were sprayed three-times with: 2% (w/v) urea, a 1% (v/v) solution of multi-component ‘Supervit R’ fertilizer, and again with 2% (w/v) urea. Combinations with diversified nitrogen fertilization were distinguished within both sub-blocks. The treatments in Experiment I consisted of: (1) Control, (2) 70 kg N ha⁻¹ as Ca(NO₃)₂, (3) 70 + 70 kg N ha⁻¹ as Ca(NO₃)₂, (4) 70 kg N ha⁻¹ as (NH₄)₂SO₄ and (5) 70 + 70 kg N ha⁻¹ as (NH₄)₂SO₄, where 70 kg N ha⁻¹ was used preplant and 70 + 70 kg N ha⁻¹ was applied preplant and as a top dressing, respectively. The treatments in Experiment II consisted of: (1) Control, (2) 35 + 35 kg N ha⁻¹ as ENTEC-26, (3) 70 + 70 kg N ha⁻¹ as ENTEC-26, (4) 105 + 105 kg N ha⁻¹ as ENTEC-26, (5) 35 + 35 kg N ha⁻¹ as NH₄NO₃, (6) 70 + 70 kg N ha⁻¹ as NH₄NO₃, (7) 105 + 105 kg N ha⁻¹ as NH₄NO₃, where 35 + 35, 70 + 70, 105 + 105 kg N ha⁻¹ was applied preplant and as top dressing, respectively. Solid nitrogen fertilizer was added to the soil, as produced: Ca(NO₃)₂—Yara International ASA (Hydro), (NH₄)₂SO₄—Zak?ady Azotowe w Tarnowie, Poland, NH₄NO₃—Zak?ady Azotowe w Pu?awach, Poland and ENTEC-26–COMPO GmbH & Co., KG, Germany. In Experiment I, the highest sugar concentrations were found in carrot fertilized with (NH₄)₂SO₄ 70, while in Experiment II in the control and after fertilization with ENTEC-26 35 + 35 kg N ha⁻¹. In both experiments N-fertilization affected an increase in phenolic compound concentrations in comparison with the control. Experiment I revealed no significant effect of N-fertilization on carotenoid concentrations in carrot, however in Experiment II the highest concentration of these compounds was characteristic for the control plants and carrot fertilized with ENTEC-26 35 + 35. The foliar nutrition applied in Experiment I caused a decline in sugar concentration and an elevated carotenoid concentration, however it had no influence on the phenolic compound concentrations in carrot. Yet the foliar nutrition in Experiment II led to a decrease in phenolic and carotenoid compound concentrations, but it did not affect sugar concentration in carrot.     

Yield and quality response of drip irrigated green beans under full and deficit irrigation

The effects of different irrigation regimes on yield and quality of green beans (Phaselous vulgaris L.) irrigated with a drip irrigation system under field conditions in the Mediterranean region of Turkey were evaluated along two years. Irrigation regimes consisted of four irrigation intervals based on four levels of cumulative pan evaporation (Epan) values (I₁: 15; I₂: 30; I₃: 45 and I₄: 60 mm); irrigations occurred on the respective treatments when Epan reached target values, and three plant–pan coefficients as for irrigation levels (Kcp₁ = 0.50, Kcp₂ = 0.75 and Kcp₃ = 1.00). Irrigation intervals varied from 2 to 4 days in I₁, 5 to 7 days in I₂, 8 to 10 days in I₃ and 10 to 12 days in I₄ treatments in 2004 and 2005 growing seasons Both irrigation levels and intervals significantly affected the green bean yields. Maximum and minimum yields were obtained from the I₁Kcp₃ and I₄Kcp₁ treatments as 24,320 and 14,200 kg ha⁻¹ in the first, and 23,850 and 13,210 kg ha⁻¹ in the second experimental year, respectively. As the Kcp value decreased the total yields in each irrigation interval also decreased. However, with the longer irrigation interval (I₄), lower yields were obtained with all Kcp coefficients. Seasonal water use (ET) values in the treatments varied from 276 mm in I₄Kcp₁ to 400 mm in I₁Kcp₃ in the first experimental year, and from 365 mm in I₄Kcp₁ to 472 mm in I₁Kcp₃ in the second experimental year. Significant linear relations were found between green bean yield and seasonal ET for each experimental year. Irrigation intervals resulted in similar water use in the treatments with the same Kcp value. Water use efficiency (WUE) and irrigation water use efficiency (IWUE) values were significantly influenced by the irrigation intervals and plant–pan coefficients. WUE ranged from 4.33 kg m⁻³ in I₄Kcp₃ to 6.08 kg m⁻³ in I₁Kcp₃ in 2004, and varied from 3.62 kg m⁻³ in I₄Kcp₁ to 5.43 kg m⁻³ in I₂Kcp₂ in the 2005 growing season. Maximum IWUE was observed in I₂Kcp₁ (6.16 kg m⁻³), and minimum IWUE was in I₄Kcp₃ treatment (3.83 kg m⁻³) in the experimental years. Both irrigation levels and irrigation frequencies had significantly different effects on quality parameters such as fresh bean length, width, number of seed per pod and 100 fresh bean weights. In conclusion, I₁Kcp₃ irrigation regime is recommended for field grown green beans under the Mediterranean conditions in order to attain higher yields with improved quality.     

Characteristics and oleocellosis sensitivity of citrus fruits

The effects of variety, growth phase, and water loss on development of oleocellosis, and relationships between chromatism and Vis/NIR spectra were studied in ‘EarlyGold’ sweet orange (Citrus sinensis Osbeck), ‘Fukumoto’ navel (Citrus sinensis Osbeck), and ‘Cara Cara’ navel (Citrus sinensis Osbeck) oranges. The varieties showed significant differences in the rate (RO) and degree (DO) of oleocellosis development. The sensitivity of varieties (from most to least sensitive) was ‘EarlyGold’ > ‘Fukumoto’ > ‘Cara Cara.’ Growth phase and water loss had a significant influence on fruit sensitivity to oleocellosis. The order of sensitivity to oleocellosis was dependent on harvest time (i.e., at normal period > at delayed period > at uncolored period), and RO and DO decreased significantly with water loss. The RO and DO models for fruit water loss were established as y = 0.75 − 3.94x − 271.33x² (R² = 0.77) and y = 1.70 − 7.29x − 1025.83x² (R² = 0.583). The sensitivity of ‘EarlyGold’ to oleocellosis was significantly correlated with dL and dC of fruit chromatism. At the same time, there were significant differences at 480–575 nm, 650–720 nm, and 925–965 nm between varieties with low and high sensitivity to oleocellosis, and ‘EarlyGolds’ with a low RO and DO had a higher reflectance than those with a high RO and DO.     

S-RNase based S-genotyping of Japanese plum (Prunus salicina Lindl.) and its implication on the assortment of cultivar-couples in the orchard

Determination of the genetic compatibility between self-incompatible cultivars is crucial in agriculture. The Rosaceae family carries the S-RNase-mediated gametophytic self-incompatibility (GSI) system. Each haplotype is conferred by an S-locus. The S-locus contains two highly polymorphic genes, S-RNase and SFB, which are characteristic of each haplotype and therefore these genes are ideal markers for molecular S-genotyping. In this study 43 Japanese plum cultivars grown in Israel were S-genotyped based on their S-RNase gene sequences. Four alleles, S^b, S^c, S^e and S^h are widespread and together are responsible for 87% of the S-haplotypes therefore many of the cultivar combinations are semi-compatible. In Israel semi-compatibility was shown to correlate with low yield. However, two cultivars, ‘Wickson’ S^fS^k and ‘Shiro’ S^fS^g carry rare S-haplotypes and, therefore, are fully compatible with most of the analyzed cultivars.     

Yield and fruit quality of ‘Nova’ hybrid [Citrus clementina hort. ex Tanaka × (C. reticulata Blanco × C. paradisi Macfad)] and two Clementine varieties (C. clementina hort. ex Tanaka) as affected by self- and cross-pollination

Low yields of ‘Nova’ citrus hybrid are common in single variety plantings (plantings consisting of one variety) due to its sexual self-incompatibility. Self-incompatibility may be overcome by cross-pollination with other compatible varieties. Fruit quality and yield of ‘Nova’ citrus hybrid as well as of the ‘SRA63’ and ‘Marisol’ Clementines, when either they were self-pollinated in single variety plantings or each one of the two Clementine varieties was used as a pollenizer for ‘Nova’ in mixed plantings (plantings consisting of more than one variety), were investigated. The study was carried out for two successive years under the same environmental and cultural conditions using three single variety plantings (‘Nova’ × ‘Nova’, ‘SRA63’ × ‘SRA63’, ‘Marisol’ × ‘Marisol’) and two mixed plantings (‘Nova’ × ‘SRA63’, ‘Nova’ × ‘Marisol’).     

High frequency early flowering from in vitro seedlings of Dendrobium nobile

Dendrobium nobile Lindl. is a popular temperate Chinese orchid commonly marketed as a traditional medicinal plant. Seedlings of Dendrobium nobile Lindl. produced floral buds (33.3–34.8%) precociously on a defined basal medium (1/2 MS) containing paclobutrazol (PP₃₃₃) at 0.5 mg L⁻¹ or thidiazuron (TDZ) at 0.1 mg L⁻¹ within 4 months of culturing. The frequency of floral buds formation can be further increased to 95.6% by growing seedlings in a PN (PP₃₃₃ 0.3 mg L⁻¹ + NAA 0.5 mg L⁻¹)-containing medium followed by transfer onto 1/2 MS medium with PP₃₃₃ and TDZ (PP₃₃₃ + TDZ). However, flower developed was deformed under 25 °C but it developed fully when grown in a lower temperature regime (23 °C/18 °C, light/dark) for 45 days. Under optimal condition, in vitro flowering was observed about 6 months after seed sowing.     

Nicht-invasive Zucker- und Festigkeitsmessung von Früchten

Zusammenfassung Ziel dieser methodischen Arbeit ist der Vergleich der konventionellen, destruktiven Bestimmung der Fruchtfestigkeit mit dem Hand-Penetrometer an geschälten Früchten bzw. mit dem ART-Penetrometer nach Ausstanzen der Fruchtschale mit dem neuen nicht-invasiven „Intelligent Firmness Detector“ (IFD). Verwendet wurden ausgelagerte Apfelfrüchte der Sorten ‘Golden Delicious’, ‘Braeburn’, ‘Topaz’ und ‘Elstar’, die im Februar 2004 zur Sortierung und zum Verkauf anstanden, und gekaufte Früchte.Der IFD misst – mit Hilfe eines Drucksensors – die Fruchtelastizität bis zu 20× entlang des Fruchtäquators, während sich die Frucht dreht. Die Werte werden automatisch korrigiert, wenn sich eine Frucht seitlich verdreht und der Apfelstiel gemessen wird. Wiederholte Messungen der gleichen Frucht zeigten die geringste Variabilität bei festen Apfelfrüchten, wobei die Abweichung mit±1–2 Einheiten des Festigkeitsindexes oder umgerechnet ±0,2 kg/cm² gering war.Die genaueste Differenzierung und beste Korrelation zwischen dem IFD und den herkömmlichen, destruktiven Methoden bestand bei festeren, vermarktungsfähigen Äpfeln wie ‘Braeburn’ über 6 kg/cm². Eine Ursache kann die einmalige Eichung des IFD mit einem Hartgummiball in oberen Messbereich sein. Die geringere Korrelation zwischen dem IFD und den beiden destruktiven Methoden bei weichen Früchten unter 4 kg/cm² wird darauf zurückgeführt, dass die Festigkeitsmessung mit dem Hand-Penetrometer durch das vorherige Schälen genauer ist, während der Stempel im ART – System die Schale erst eindrückt und dann ausstanzt bevor er das Fruchtfleisch durchdringt und die Festigkeit somit ebenso überschätzt.Die nicht-invasive Zuckerbestimmung mit dem „Intelligent Fruit Analyser“ (IFA) beruht auf bis zu fünf optischen Transmissionsmessungen pro Frucht im Bereich 400–1100 nm. Alle Transmissionsspektren zeigten die typische Chlorophyllabsorption bei 672–679 nm und darüber im NIR – Bereich zwei Spitzenwerte bei 710–730 nm und 814–824 nm. Bei diesem Verfahren wird die ganze Frucht, d. h. z. B. ein Apfel, eine Kiwi oder Apfelsine durchleuchtet. Die VIS/NIR – Transmissionsspektren werden mit einem Siliziumdetektor mit Diodenarray unter der Frucht aufgezeichnet, einer Faktorenanalyse unterzogen und vor der Messreihe mit den im Refraktometer gemessenen Zuckergehalten der gleichen Früchte korreliert. Die Korrelation stieg bei nur 50 Früchten von r² = 0,62 bei ‘Elstar’ durch eine größere Stichprobe auf r² = 0,84. Bei derart hohen r²-Werten betrug die Genauigkeit der Zuckerbestimmung mit dem IFA ca. 4%, d. h. ±0,65°Brix bei Zuckergehalten in Äpfeln von 14–19°Brix.Beim Zuckermodul IFA ist entweder eine umfangreiche, repräsentative Stichprobe oder sowohl für jede Sorte als auch für unterschiedliche Standorte eine eigene Korrelation notwendig, die der Hersteller berechnet und im IFA speichert. Bei beiden Bestimmungen mit dem IFD und IFA traten keine Druckstellen oder sonstige Schäden an den untersuchten Früchten auf.     

Estimation of individual leaf area,fresh weight,and dry weight of hydroponically grown cucumbers (Cucumis sativus L.) using leaf length,width, and SPAD value

Non-destructive and mathematical approaches of modeling can be very convenient and useful for plant growth estimation. To predict individual leaf area, fresh weight, and dry weight of a cucumber (Cucumis sativus L.), models were developed using leaf length, leaf width, SPAD value, and different combinations of these variables. Eight regression equations, commonly used for developing growth models, were compared for accuracy and adaptability. The three nonlinear models developed were as follows: individual leaf area (LA) = −210.61 + 13.358W + 0.5356LW (R² = 0.980^***), fresh weight (FW) = −2.72 + 0.0135LW + 0.00022LWS (R² = 0.956^***), and dry weight (DW) = 0.25 − 0.00102LS + 0.000077LWS (R² = 0.956^***), where L is the leaf length, W the leaf width, S the SPAD value, and LWS = L × W × S. For validation of the model, estimated values for individual leaf area, fresh weight, and dry weight showed strong agreement with the measured values, respectively. Leaf dry weight, especially, was estimated with a higher degree of accuracy through the use of a SPAD value, as well as leaf length and width. Therefore, it is concluded that models presented herein may be useful for the estimation of the individual leaf area, fresh weight, and dry weight of a cucumber with a high degree of accuracy.     

Water relations between leaf water potential,photosynthesis and agronomic vine response as a tool for establishing thresholds in irrigation scheduling

During the last few years, leaf water potential has been a useful tool in controlling vine water status. However, the time of measurement that could best explain short- and long-term vine responses remains a matter of discussion. The objectives of this work were to study the relationship between vine water status and vine performance and to determine what time of day leaf water potential is best correlated to physiological performance and agronomic vine response. The assay was conducted in Madrid, Spain. Plant material was Cabernet-Sauvignon (Vitis vinifera L.) grafted onto SO₄. Three irrigation treatments were established: T1 was non-irrigated, and T2 and T3 were irrigated with a constant fraction of the ETo, k = 0.45 and 0.2, respectively. Vine water status was monitored through predawn, midmorning and noon leaf water potential. Their relationships with net CO₂ assimilation rate, vegetative growth rate, yield components and must composition at harvest were studied for 3 consecutive years. Shoot growth rate and net CO₂ assimilation rate were better correlated with midmorning and noon leaf water potentials – Ψ_m and Ψ_n – than predawn leaf water potential – Ψ_pd – but all of them were significant. Shoot growth rate was zero for Ψ_pd = −0.48, Ψ_m = −1.12 and Ψ_n = −1.18 MPa. Berry size was better correlated with the water stress integral for predawn (S_Ψpd$S_{{\Psi }_{\text{pd}}}$) although the water stress integral for midmorning (S_Ψm$S_{{\Psi }_{\text{m}}}$) and noon (S_Ψn$S_{{\Psi }_{\text{n}}}$) performed quite well. No relationship was found between the water stress integral and TSS, total acidity or pH. Leaf water potential performed as a good parameter for determining both vine water status and agronomic response, but not for evaluating must composition.     

Chemical changes during myrtle (Myrtus communis L.) fruit development and ripening

The chemical composition of fruit belonging to ‘Barbara’ and ‘Daniela’ myrtle cultivars was monitored during development from fruit-set to an over-ripe stage (July–January), with the aim to identify a reliable maturity index. Acidity, pH, reducing and total sugars, phenols, tannins, anthocyans, carbon dioxide and ethylene production rates were monitored over two different year seasons. Titratable acidity decreased during maturation, with significant differences due to cultivar and year of observation. Reducing sugars increased in both cultivars approximately sevenfold from fruit set to complete maturation. Total sugar content increased similarly ranging from 1.43% and 1.41% at fruit set to 8.28% and 7.56% at maturation for ‘Barbara’ and ‘Daniela’, respectively. Total phenols and tannins occurred at high levels after fruit set and declined during development. Anthocyans levels increased, in both cultivars, according to a sigmoid curve. The pattern of respiration rate showed a gradual decline in both cultivars ranging from 365.81 and 396.42 mg kg⁻¹ h⁻¹ to 79.98 and 52.27 mg kg⁻¹ h⁻¹, respectively for ‘Barbara’ and ‘Daniela’ in 2006. A peak of variable size was observed in October–November period. Small increases in ethylene production have been detected during fruit development ranging from 130.57 and 269.14 μL kg⁻¹ h⁻¹ measured at the onset of development to 13.04 and 19.36 μL kg⁻¹ h⁻¹ measured at harvest for ‘Barbara’ and ‘Daniela’, respectively.