Characterisation of citrus rootstock germplasm introduced as seeds to Australia from the People's Republic of China

Seeds were collected from a range of citrus rootstock types in China and sent to Australia for evaluation. Before evaluation proceeded, however, the seeds and their seedlings were characterised for uniformity and trueness-to-type. The seeds were cultured in vitro and/or germinated in sand beds to assess whether or not they were mono- or polyembryonic. Seedlings were then rogued on the basis of vigour and morphology before isozyme profiles were developed from leaf extracts to assess seedling uniformity within introductions. Isozyme profiles were also compared to those of the source trees, as well as hybrids generated between some of them in China, to assess and verify trueness-to-type. The degree of variability between the seedlings propagated from the imported seeds and their source trees in China differed between accessions, which highlighted some of the issues that need to be considered when importing citrus germplasm as seeds. Regardless of whether the seedlings could be shown to be identical to their source tree in China, three uniform seedlings of polyembryonic types were established in arboreta as Australian source trees to provide propagules for evaluation and possibly commercial use.     

Chloride and sodium excluding capacities of citrus rootstock germplasm introduced to Australia from the People's Republic of China

The responses to root zone salinity (0, 25 and 50 mM NaCl) by 40 citrus rootstock genotypes introduced from the People's Republic of China, measured as shoot chloride (Cl⁻) and sodium (Na⁺) ion accumulation, growth and dry matter accumulation, were investigated under glasshouse conditions. Two experiments, one using aerated nutrient solutions and the other irrigated sand cultures, were conducted with plants grown from rooted cuttings taken from representative trees of different mandarin (Citrus reticulata Blanco and C. erythrosa Hort. ex Tan.), yuzu (C. junos Sieb. ex Tan.), Ichang papeda (C. ichangensis Swing.), sour orange (C. aurantium L.) and trifoliate orange (Poncirus trifoliata (L.) Raf.) genotypes. Two standard genotypes, viz. Rangpur lime (Citrus x limonia Osbeck.) and William's trifoliate orange were included in the experiments as reference controls.     

Effect of a cytochrome P450 inhibitor on abscisic acid biosynthesis and stomatal regulation in citrus trees in water-stressed conditions

The effect of diniconazole, an inhibitor of cytochrome P450, on drought tolerance was examined in ‘Shiranui’ [(Citrus unshiu Marc. × Citrus unshiu Osbeck) × Citrus reticulate Blanco] trees. Diniconazole treatment increased abscisic acid (ABA) concentration in leaves compared with untreated controls in water-stressed conditions after 20 days of water-stress treatment. Diniconazole significantly decreased the stomatal aperture at 9 h after application compared with untreated controls in water-stressed conditions. The photosynthetic rate decreased in water-stressed conditions; however, regardless of the earlier stomatal closure induced by diniconazole application, the decrease of photosynthetic rate was delayed by the application.     

Cybrid/hybrid plants regenerated from somatic fusions between male sterile Satsuma mandarin and seedy tangelos

Somatic hybridization provides an alternative for transferring mitochondria-encoded cytoplasmic male sterility (CMS). Herein, symmetric protoplast electrofusion was conducted between embryogenic callus protoplasts of Citrus unshiu Marc. cv. Guoqing No. 1 (G1), a CMS cultivar, and mesophyll-derived protoplasts of seedy ‘Page’ tangelo [C. reticulata Blanco × (C. reticulata Blanco × C. paradisi Macf.)] or ‘Nova’ tangelo [C. reticulata Blanco × (C. reticulata Blanco × C. paradisi Macf.)], to transfer CMS trait. Flow cytometry analysis showed that 14 plants recovered from G1 + ‘Page’ tangelo that displayed typical morphological character of ‘Page’ were diploid, and 6 plants regenerated from G1 + ‘Nova’ tangelo were tetraploid. Genetic compositions of regenerated plants from the two fusions were determined by SSR, CAPS and chloroplast-SSR analysis. Cybrid nature of diploids from G1 + ‘Page’ tangelo with nuclear DNA from ‘Page’, mitochondrial DNA (mtDNA) from the G1 and chloroplast DNA (cpDNA) derived from either parent was confirmed. Tetraploid plants from G1 + ‘Nova’ tangelo were identified as somatic hybrids with random cpDNA inheritance. The regenerated cybrid and hybrid plants hold great potential for Citrus seedless breeding at diploid or triploid levels.     

Relation of carbohydrate reserves with the forthcoming crop,flower formation and photosynthetic rate,in the alternate bearing ‘Salustiana’ sweet orange (Citrus sinensis L.)

The aim of this work was to assess the relation between carbohydrate levels and flower and fruit production, as well as the role of carbohydrates on CO₂ fixation activity, by analysis of leaves, twigs and roots from the alternate bearing ‘Salustiana’ cultivar of sweet orange (Citrus sinensis [L.] Osbeck). A heavy crop load (on year) did not affect photosynthesis activity when compared to non-fruiting trees (off year). Fruiting trees accumulated most of the fixed carbon in mature fruits, whilst no accumulation was observed in roots before harvest. Non-fruiting trees transported part of the fixed carbon to the roots and mobilize it for growth processes and, at the end of the season (December), store it as reserves. Reserve carbohydrates accumulation in leaves started by early December for both tree types, showing the same levels in on and off trees until spring bud sprouting. A heavy flowering after an off year caused the rapid mobilization of the stored reserves, which were exhausted at full bloom. We found no evidence on carbon fixation regulation by either fruit demand or carbohydrate levels in leaves. Carbohydrate reserves played little or no role over fruit set, which actually relied on current photosynthesis.     

杧果MADS-box基因保守区片段的克隆与序列分析

为从杧果中克隆新的MADS-box基因,利用MADS-box转录因子的保守特征设计简并引物,应用RT-PCR从杧果花序中成功分离出14条MADS-box基因cDNA片段。片段长度在138~147bp之间,推导的氨基酸序列与已知的杧果MADS-box基因的同源性为65.2%~82.6%。用推导的氨基酸序列与已知的杧果和拟南芥MADS-box基因进行系统发育分析,可将这些片段归入MADS-box的不同亚家族中。表明杧果花序中存在多种MADS-box转录因子,参与杧果花器官的发育及开花时间的调节。     

蕙兰B类MADS-box基因的克隆及表达分析

 采用RT-PCR结合RACE技术从蕙兰（Cymbidium faberi）中分离到3个B类MADS-box基因CfGLO、CfDEF1和CfDEF2,分别编码210、222和227个氨基酸。系统进化树分析显示,CfGLO属于PI/GLO类基因,CfDEF1和CfDEF2分别属于PaleoAP3组基因的PeMADS2类基因和PeMADS3类基因。RT-PCR和实时荧光定量表达分析表明,CfDEF1在2、3轮花器官侧瓣、唇瓣和蕊柱中强烈表达,在萼片中不表达;CfDEF2在1、2、3轮花器官中都表达,在营养组织中不表达;而CfGLO在所有组织中都表达,说明3个基因在蕙兰花器官的形成过程中可能扮演着不同的角色。此外,3个基因都在蕙兰幼嫩子房中有表达,显示其可能在蕙兰子房的形成过程中起一定作用。     

Pome fruit viruses at the Canadian Clonal Genebank and molecular characterization of Apple chlorotic leaf spot virus isolates

A survey for apple and pear viruses was carried out at the Canadian Clonal Genebank (CCG), Harrow, Ontario, Canada, during the fall/winter of 2007 and spring of 2008. Leaves and/or dormant cuttings were randomly collected from 438 to 122 accessions of apple and pear, respectively. Samples were tested by Double Antibody Sandwich-Enzyme Linked Immunosorbent Assay (DAS-ELISA) for the presence of Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV) and Apple mosaic virus (ApMV). Infection rates for apples were ACLSV (48.1%), ASGV (10%), ASPV (6.6%) and ApMV (7.1%), and for pears ACLSV (42.6%). ACLSV was detected and characterization by multiplex RT-PCR with primers targeting a fragment of 677 bp corresponding to the partial coat protein (CP), movement protein (MP) and untranslated (3′UTR) region in 22 accessions of apple and pear. Multiplex RT-PCR showed a higher sensitivity over the ELISA test. The nucleotide and amino acid deduced partial CP identities ranged from 82.6–100% to 91–100%, respectively, while partial MP identities was 62.5–100% at aa level based on the amplified fragment appropriate for partial MP using a frame shift, among 22 ACLSV isolates. Phylogenetic analyses based on the partial CP region clustered CCG ACLSV isolates in two different groups, while those based on the partial MP region embraced CCG ACLSV isolates in two sub-clusters within the same group. This is the first report on the detection of ACLSV, ASPV, ASGV and ApMV at CCG, and the molecular characterization of ACLSV isolates in apple and pear plants from worldwide countries to deduce possible heterogeneity and evolution.     

Selection of arbuscular mycorrhizal fungi for citrus growth promotion and Phytophthora suppression

In order to reduce unnecessary amount of P-fertilizer and severity of Phytophthora root rot in citrus orchards, the experiment was set up. Thirteen indigenous arbuscular mycorrhiza (AM) fungi species were isolated from rhizosphere soil of citrus orchards in Thailand and were then propagated into three host plants [sorghum (Sorghum bicolor), maize (Zea mays), and leek (Allium cepa)] by trap culture. We also tested whether indigenous AMF species (13 different species) could colonize into three cultivars of citrus scions and rootstocks (Shogun: Citrus reticulata Blanco cv. Shogun; Tangerine: C. reticulata; and C-35 citrange: Citrus sinensis × Poncirus trifoliata). With root colonization rates, the results indicated that Acaulospora tuberculata and Glomus etunicatum provided the best colonization in all citrus cultivars. We selected, therefore, those AMF species to verify their influences on citrus growth and Phytophthora root rot resistance. Three cultivars of citrus scions and rootstocks, Shogun, Tangerine and C-35 citrange, were inoculated with two effective indigenous AMF species, G. etunicatum or A. tuberculata in order to determine the influences on citrus growth. The plants were investigated to determine the mycorrhizal efficiency index (MEI), AM colonization, P content, and other parameters. Co-inoculation of AMF species (G. etunicatum or A. tuberculata) with Phytophthora nicotianae was also carried out in Shogun scion/C-35 citrange rootstocks. The results of citrus growth revealed that Shogun and Tangerine inoculated with G. etunicatum produced the highest MEI. Tangerine and C-35 citrange amended with fertilizers and G. etunicatum showed the highest P content in leaves. This indicated that G. etunicatum has an influence on citrus growth and P uptake, suggesting it to be the highly effective strain. Shogun scion/C-35 citrange rootstock combinations that were inoculated by both P. nicotianae and different AM fungi (G. etunicatum or A. tuberculata) showed root injury at low level of root rot symptom. However, the part of Shogun scions grafted on rootstocks showed severe symptom of shoot die back in treatment inoculated with P. nicotianae alone, while treatment inoculated with different AM species (G. etunicatum or A. tuberculata) and P. nicotianae rendered lower shoot die back symptoms than that of Phytophthora treatment. The low level of shoot die back symptom was shown at first, then healthy young shoot was restored. Our results indicated the facts that different host plants and different AMF species produced different outcomes of growth and pathogen resistance. The application of both AM isolates, therefore, has an enormous potential to be produced the inoculum for citrus orchards.     

Effect of shade regime on flower development,yield and quality in lisianthus

The effects of shading on lisianthus (Eustoma grandiflorum) floral transition, plant development, flower yield and quality, and content of starch and soluble sugars were assessed in three cultivars, over two consecutive years. Shading nets affording 67% or 88% reduction in light intensity, were fitted at planting in the greenhouse for periods ranging from 3 to 8 weeks. Meristem morphology at floral transition was characterized by apical meristem widening and the appearance of two bract primordia. Floral transition time was affected by cultivars, but in general, longer and heavier shade treatments delayed floral transition; the longest delay (6 weeks) being recorded in Mariachi White under 88% shade for 7 weeks or under a combined shade treatment of 88% for 3 weeks followed by 67% for 5 weeks. Despite interactions between cultivar and shade treatment, consistent trends were discerned: the heaviest and most prolonged shading reduced yield (up to 40%), cut stem length (up to 15%), and number of flower buds/stem (up to 26%), within cultivar. Total carbohydrates levels were very low, and it is questionable whether changes observed in carbohydrate quantity following shade treatments had any effect on plant growth or flower yield. Rather, it appears that lisianthus is very dependent on current photosynthesis, so that even a brief shading interlude could reduce branching and flower quality. It may be concluded that the intensive shading usually applied is detrimental for lisianthus.     

Temperature responses,flowering and fruit yield of the June-bearing strawberry cultivars Florence,Frida and Korona

The effect of night temperature on short day (SD) floral induction has been studied in three June-bearing strawberry cultivars of different geographic origin and compared with yield performance in the cool Nordic environment. At the optimum day temperature of 18 °C, the SD flowering response of the cultivars ‘Florence’ and ‘Korona’ increased significantly with increasing night temperature from 9 to 18 °C, while an optimum was reached at 15 °C in the cultivar ‘Frida’ that is selected under cool-environment conditions in Norway. Also, while saturated flowering response was obtained with 3 weeks of SD treatment at all temperatures in ‘Frida’, several plants of ‘Florence’ and ‘Korona’ failed to initiate flowers at 9 °C night temperature even with 5 weeks of SD. The effect of extended SD period was particularly pronounced in ‘Florence’. The slow SD floral induction response of ‘Florence’ was associated with a 2 week delay of anthesis in subsequent long day (LD) conditions at 21 °C. Yield performance of the same cultivars during 2 years under field conditions at Nes Hedmark and in North Norway also demonstrated that the yield potential of ‘Florence’ was not realized under the climatic conditions prevailing at these locations. In both years the yields varied significantly among the cultivars, ‘Frida’ having the highest yields followed by ‘Korona’, with ‘Florence’ far below. It is concluded that, in the Nordic environment, autumn (September) night temperatures are obviously sub-optimal for yield performance of some June-bearing strawberry cultivars, and that this effect is mediated by autumn temperature effects on flower initiation responses.     

辣椒花器官发育MADS-box基因的克隆与表达分析

采用RACE技术从辣椒（Capsicum annuum L.）花药中获得了一个控制辣椒花器官发育的MADS-box基因,命名为PPI（GenBank登录号：GU812276）。该基因全长952 bp,编码215个氨基酸,具有典型的MADS结构域和K结构域,与番茄花器官发育MADS-box基因TPI高度同源,同源性达88%。系统进化树分析表明,PPI基因属于花器官发育B类基因。RT-PCR表达分析表明,该基因在辣椒花瓣中的表达高于在花药、萼片以及子房等花器官中的表达,在营养器官叶片中没有表达。     

Evidence for a translocatable florigenic promoter in mango

Movement of a putative florigenic promoter from leaves to buds was investigated in two cultivars of mango (Mangifera indica L.) over two flowering seasons through examination of the minimum number of leaves on each stem necessary for floral induction and movement of this component over various distances from stem to stem in isolated branches. The minimum number of leaves on individual stems necessary to induce flowering was less than 1/4 of a cross-cut leaf per stem. The putative florigenic promoter moved from donor stems bearing as few as one leaf to induce flowering in five receiver stems located as far down branches as 100 cm from the donor stem. Evidence suggests that movement of the putative florigenic promoter occurs in phloem and that far more of this component is available in trees than is necessary for floral induction of initiating shoots during cool, floral-inductive conditions of the subtropics.     

大蒜MADS-box基因AsPI的克隆及表达分析

B类MADS-box基因在调控显花植物的花瓣和雄蕊发育过程中发挥关键作用。为初步了解大蒜花发育的分子机制,以‘阿城紫皮’大蒜(Allium sativum)的花蕾为试材克隆了AsPI(Gen Bank登录号为KY272748)。AsPI的cDNA长939 bp,开放阅读框为615 bp,编码204个氨基酸。推导的氨基酸序列显示,AsPI编码的蛋白质包含高度保守的MADS结构域(1~57氨基酸)和保守的K结构(76~140氨基酸),AsPI蛋白具有PI亚家族特有的序列特征:MADS区特征丝氨酸残基、K区高度保守序列KHExL以及C–末端的PI基序。序列比对、功能域分析及系统发育分析结果表明,AsPI属于单子叶植物B功能基因PI亚家族。半定量和实时RT-PCR检测AsPI在大蒜不同组织器官中的表达模式,结果表明,在花蕾中高丰度表达,在花茎中表达量中等,在根、假茎、嫩叶、保护叶等营养器官中表达量极低甚至不表达。     

DNA content,morphometric and molecular marker analyses of Citrus limonimedica, C. limon and C. medica for the determination of their variability and genetic relationships within the genus Citrus

This work investigated the fingerprinting and phenotyping of Citrus germplasm; species selected were of historical importance belonging to Citrus limonimedica Lush. and its supposed ancestors, along with some other species of the Citrus genus. An integrated approach based on the exploitation of nuclear DNA content, morphological traits and molecular markers, such as RAPD fingerprints and ITS-based SNPs, was employed. We studied a core collection of 54 distinct accessions, including 43 genotypes of the Citrus species (18 species or supposed species) and 11 genotypes of the Poncirus genus, which was used as the reference outgroup. Morphological trait analysis and statistical analysis of DNA content and markers were useful for reconstructing a Citrus phylogeny. In particular, our experiments aimed at estimating the genetic variation within and the genetic relatedness among C limon (L.) Burm., C. limonimedica and C. medica L. to shed light on the hybrid origin hypothesis of C. limonimedica. The results of the multidisciplinary analyses allowed us to confirm a remarkable differentiation between Poncirus and Citrus genera and to highlight a close relationship among the three investigated Citrus species but a distinct difference between these three species and other species in the Citrus genus. RAPD fingerprints and ITS polymorphisms enabled us to point out a variation gradient between lemon and citron, with C. limonimedica as a possible intermediate species. Some accessions of C. medica and C. limonimedica that deviate from such a trend suggest recurrent introgression and/or hybridisation with other species of Citrus.     

Chemical compositions and insecticidal effects of essential oils isolated from Achillea gypsicola, Satureja hortensis, Origanum acutidens and Hypericum scabrum against broadbean weevil (Bruchus dentipes)

The essential oils of aerial parts of Achillea gypsicola Hub.-Mor., Hypericum scabrum L., Satureja hortensis L., and Origanum acutidens (Hand.-Mazz.) Letswaart were analyzed in this study by GC and GC–MS and their oils were tested for toxicity against broadbean weevil (Bruchus dentipes). A. gypsicola oil contained camphor (40.17%), 1,8-cineole (22.01%), piperitone (11.29%), borneol (9.50%) and α-terpineol (1.56%) as major components. A total of 74 components were identified by GC–MS in H. scabrum oil, including α-pinene (9.26%), terpinen-4-ol (5.12%), camphor (5.94%), δ-cadinene (4.52%), pulegone (4.45%), γ-muurolene (4.12%), pinocarvone (3.97%) and β-caryophyllene (3.42%) as predominant components. The essential oils of O. acutidens and S. hortensis were characterized by high contents of carvacrol (86.99% and 55.74%), γ-terpinene (0.71% and 20.94%), p-cymene (1.95% and 12.30%), α-terpinene (0.13% and 2.04%) and β-caryophyllene (1.30% and 1.08%). All of the essential oils were toxic to adults of B. dentipes and insect mortality increased with increasing concentration of each oil. The oils (20 μl dose) brought about 100% mortality in 36 h. Although desirable insecticidal activities against the pest were achieved with the oils from all four plant species, S. hortensis and O. acutidens oils were more effective, particularly after 6 h of treatment. The current results concluded that the essential oils, in particular O. acutidens and S. hortensis oils, may be used as potential botanical insecticides against B. dentipes.     

Comparative analysis of genetic diversity in Citrus germplasm collection using AFLP,SSAP, SAMPL and SSR markers

In this study we evaluate the informativeness and efficiency of Amplified Fragment Length Polymorphism (AFLP), Sequence-Specific Amplified Polymorphism (S-SAP), Selectively Amplified Microsatellite Polymorphic Loci (SAMPL) and Simple Sequence Repeat (SSR) markers for genetic diversity, phylogenetic relationship among the Citrus species and mapping ability of the marker system. The SSR exhibited relatively higher level of polymorphism information content in terms of the expected heterozygosity, than that of the AFLPs, SSAPs and SAMPLs. For each marker system, average level of the discriminating potential was very close to the actual discriminating potential. Similarity matrices showed weak, yet significant correlations when Mantel's test was applied. The highest positive (0.72) correlation was found between the AFLP and SSAP markers. The SSR and SAMPL markers were poorly correlated. The dendrogram topology among the four marker systems had high similarity. Taken together, the SSAP and SAMPL were highly efficient in detecting genetic similarity in Citrus, while the SSR may be more useful for segregation studies and genome mapping in Citrus. The SSAP and SAMPL markers could be useful for Citrus genome mapping in combination with AFLP and SSR markers. To our knowledge, this was the first detail report of a comparison of performances among AFLP, SSR and retrotrasposon based molecular marker technique on a set of samples of Citrus. Our result provides guidance for future efficient use of these molecular methods in genetic analysis of Citrus sp. and its relatives.     

黄瓜MADS-box基因家族生物信息学分析及CsMADS-box AGL62的克隆

分别以全雌系D1104-2-4、强雌系D1158♀-2、雌雄异花同株D0528-2为母本,与1个雌雄异花同株父本D0708-2杂交获得杂种一代,调查开花初期、根瓜期、盛果期3个时期雌性相关农艺性状,筛选出差异显著的组合进行转录组测序分析进而分析黄瓜杂交组合间MADS-box家族的差异基因。结果表明:以全雌系D1104-2-4为母本的杂种一代C15-114在雌花数、雌花节率上均具有超亲优势,3个杂交组合F1均具有早熟的中亲优势。转录组分析结果发现,以全雌系D1104-2-4为母本的杂种一代基因表达情况显著的偏向母本,挑选的37个黄瓜MADS-box家族基因只有6个与母本有表达差异,17个与父本有表达差异。生物信息学分析并命名了1个差异最显著的基因Cs MADS-box AGL62,该基因全长745 bp,编码187个氨基酸,编码的蛋白属于线粒体中不稳定的亲水性跨膜蛋白,NCBI比对结果表明该蛋白是1个转录因子,系统进化分析发现其与甜瓜中AGL62同源性最高,在黄瓜中该蛋白和其他黄瓜AGL62亚型属于同一分支并且属于I型。     

Selection and testing of epiphytic yeasts to control anthacnose in post-harvest of papaya fruit

Anthracnose, caused by Colletotrichum gloeosporioides, is a major post-harvest disease in papaya fruit. The major objectives of the present work were to isolate, select and test the in vitro and in vivo ability of epiphytic microorganisms, isolated from papaya fruit and leaf surfaces, in controlling anthracnose onset after harvest. A total of 75 bacteria, 67 yeasts and 22 mycelial fungi were isolated. Thirty yeast isolates were able to inhibit the mycelial growth of C. gloeosporioide in vitro and seven of those were used in in vivo assays, resulting in the identification of two very effective isolates. Isolate CEN63, identified molecularly as Cryptococcus magnus, was the most effective in controlling the disease and therefore was studied in more detail. The results of the assays with C. magnus provided evidence that when fruit were treated with the antagonists at concentrations of 10⁷ to 10⁸ cells/ml, as early as 24 h, preferentially 48 h, before inoculation with the pathogen, the development of disease was significantly reduced. C. magnus is a potential antagonist for the development of a commercial product. Additional studies on the modes of action of this yeast isolate, as on its ability to interact with fungicides are being conducted to generate solid basis for the development of an environmentally friendly control agent.     

Eggplant relatives as sources of variation for developing new rootstocks: Effects of grafting on eggplant yield and fruit apparent quality and composition

We propose the utilization of eggplant (Solanum melongena L.) interspecific hybrids derived from crosses with closely related species as an approach for developing new improved rootstocks for eggplant. Here we investigate rootstock effects on fruit yield, apparent quality and proximate and mineral composition of S. melongena ‘Black Beauty’ (BB) scions grafted on interspecific hybrid rootstocks developed from crosses of S. melongena with Solanum incanum L. (SI × SM) and Solanum aethiopicum L. (SM × SA). The results are compared with non-grafted (BB control) and self-grafted (BB/BB) controls and with S. melongena ‘Black Beauty’ scions grafted onto Solanum torvum Sw. (STO) and Solanum macrocarpon L. (SMA) rootstocks. All treatments were grown in a soil naturally infested with root-knot nematodes (mostly Meloidogyne incognita (Kofoid and White) Chitwood). SI × SM and SM × SA interspecific hybrids had high germination (≥90%) and total graft success (100%). Contrary to what occurred with all other treatments, no plants from scions grafted onto these hybrid rootstocks died during the experiment. In particular, the SI × SM hybrid rootstock conferred the highest vigour to the scion, which resulted in the highest values for fruit earliness and early and total yield. Little difference was observed among treatments for apparent fruit quality traits, except for a greater fruit calyx length and prickliness of fruit grafted onto SMA rootstocks. A similar result was obtained for fruit composition where phenolics content was higher in fruit from plants grafted onto SMA rootstocks. Grafting eggplant onto interspecific eggplant hybrids, especially on the SI × SM hybrid, has proved advantageous for eggplant production, as the high vigour and good compatibility of the rootstock with scion results in improved early and total yield without negative effects on apparent fruit quality or composition. Interspecific hybrids represent an alternative to the commonly used STO rootstock, which is a wild species with irregular germination.