Dissertations / Theses on the topic 'Grapevine pruning'

Thesis (PhD)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Grapevine trunk diseases are a cause of decline and loss of productivity in grapevines at all stages of growth. These diseases are caused by a complex of wood-inhabiting fungi that infect mainly through pruning wounds. The management of these diseases relies on wound protection to prevent infection since there are no eradicative control measures to cure infected vines. There are few or no fungicides registered for grapevine pruning wound protection in most countries, while Trichoderma biocontrol agents are often available. This study aimed at improving grapevine wound protection by Trichoderma (T.) spp. and to gain a better understanding of the factors and mechanisms involved in biocontrol. The effect of pruning time (early or late) and five timings of application of the biocontrol agent after pruning on pruning wound colonisation by T. atroviride and T. harzianum were determined. Chenin blanc and Cabernet Sauvignon vineyards were pruned in July (early) and August (late) of 2011 and 2012, and pruning wounds were treated with suspensions of the Trichoderma spp. at various times (0, 6, 24, 48 and 96 hours) after pruning. Wound colonisation was depended on the physiological state of the vine at pruning for both cultivars. However, for the 2012 season in Chenin blanc, wound colonisation was similarly high for both pruning times, which was attributed to high rainfall and humidity. Application of the biocontrol agents 6 hours after pruning consistently resulted in high wound colonisation by the Trichoderma spp. in both cultivars and pruning times. In both cultivars, pruning wound infection due to natural inoculum was higher in wounds made in late winter than those made earlier. The effect of conidial formulation in nutritional (glucose, yeast extract and urea) and bio-enhancing (chitin and cell free culture filtrates) additives, on pruning wound colonisation by T. atroviride was also investigated. Nutritional additives increased the extent of pruning wound colonisation by T. atroviride compared to the un-amended conidial suspensions in a glass house study. The additives as well as Garrison, a fungicide containing pruning wound paint, and Eco77®, a registered T. harzianum biocontrol product, were tested in field trials for wound protection from infection by Phaeomoniella (Pa.) chlamydospora. In 2011, the pathogen was inoculated a day after pruning and all the Trichoderma spp. treatments similarly reduced Pa. chlamydospora infection by 75% to 90% in Thompson Seedless, while control was less in Chenin blanc and ranged from 40% to 74%. In 2012, the trial was carried out on Chenin blanc only and the pathogen was inoculated at intervals of 1, 3 and 7 days after pruning. Wound protection by the Trichoderma treatments was highest when wounds were inoculated with Pa. chlamydospora seven days after pruning. Two conidial formulations, a culture filtrate made from a chitin based medium and a combination of yeast extract, urea and glucose, consistently enhanced biocontrol efficacy. These formulations reduced Pa. chlamydospora infection to levels similar to those of Garrison. The integration of chemical and biological wound protection could provide both immediate and long term wound protection, but is limited by the sensitivity of the biocontrol agent to fungicides. Benzimidazole resistant Trichoderma strains were generated by gamma irradiation from the wild type isolates of T. atroviride (UST1 and UST2) and T. harzianum (T77). Mutants from UST1 and UST2 were of similar biological fitness as the wild type isolates and retained their in vitro antagonistic activity against grapevine trunk pathogens, while the mutant from T77 had reduced fitness and was not antagonistic to the pathogens. The wild type, UST1, and its mutant were tested alone and in combination with thiophanate methyl and carbendazim, respectively, for their ability to prevent pruning wound infection by Pa. chlamydospora. The combination of the UST1 mutant and carbendazim was the most effective treatment and gave the highest reduction in Pa. chlamydospora infection (70% to 93% control). Grapevine cell cultures were used to compare the response of grapevines to T. atroviride and Eutypa (E.) lata as a first step to determining the importance of Trichoderma-grapevine interactions in pruning wound bio-protection. The expression of genes coding for enzymes of the phenylpropanoid pathway and pathogenesis related (PR) proteins was profiled over a 48-hour period using quantitative reverse transcriptase PCR. The cell cultures responded to fungal elicitors in a hypersensitive-like response that lead to a decrease in cell viability. Fungal elicitors from both fungi triggered the same genes and caused up-regulation of phenylalanine ammonia-lyase (PAL), 4 coumaroyl Co-A ligase (CCo-A), stilbene synthase (STS), chitinase class IV (CHIT IV), PR 3 and PR 4, and a down regulation of chalcone synthase (CHS) genes. Higher expression of PAL and CHIT IV in cell cultures treated with the T. atroviride elicitor led to a significantly higher (P < 0.05) total phenolic content and chitinolytic enzyme activity of the cell cultures compared to cell cultures treated with the E. lata elicitor. The response of the cell cultures to the T. atroviride elicitor signifies that the induction of grapevine resistance may be involved in wound bio-protection. The role of secondary metabolites produced by Trichoderma spp. used in pruning wound protection was also investigated. A volatile antimicrobial compound, 6-pentyl α-pyrone (6PP), was isolated and found to be the major secondary metabolite from the T. atroviride (UST1 and UST2) and T. harzianum (T77) isolates. This metabolite was found to inhibit mycelial growth, spore and conidia germination of E. lata, Neofussicocum (N.) australe, N. parvum and Pa. chlamydospora. The production of 6PP was induced when the T. atroviride isolates were grown in a grapevine wood extract medium while for UST1, the 6PP concentration was further doubled when it was co-cultured with N. parvum. Results therefore, indicate that 6PP is involved in the Trichoderma-pathogen interactions on pruning wounds. The results of this study have provided new information in regards to the application of Trichoderma-based pruning wound products. The best time of application proved to be 6 hours post pruning. The formulation of conidial suspensions of Trichoderma spp. with nutritional additives and in protein extracts of the biocontrol agent showed potential in reducing variability of wound bio-protection. However, further research would be necessary to develop commercial products. The application of a fungicide together with Trichoderma spp. in the field holds promise to improve control, but would require further trials for possible commercialisation. This study is the first to report on grapevine host defence genes that are activated by the Trichoderma spp. used in pruning wound protection. Together with the characterisation of the major secondary metabolite produced by these Trichoderma spp., this information aids in understanding the mechanisms involved in the complex interaction between the biocontrol agent, the host and the pathogen.
AFRIKAANSE OPSOMMING: Wingerdstamsiektes veroorsaak terugsterwing en verlies aan produktiwiteit in wingerdstokke gedurende alle groeifases. Hierdie siektes word veroorsaak deur „n verskeidenheid van hout-koloniserende swamme wat die wingerdstok meestal deur snoeiwonde infekteer. Die bestuur van hierdie siektes is afhanklik van wondbeskerming om infeksie te verhoed, omdat daar geen uitwissende beheermetodes na infeksie bestaan nie. In meeste lande is daar min of geen swamdoders geregistreer vir snoeiwond beskerming, terwyl Trichoderma biobeheer agente gereëld beskikbaar is. Hierdie studie poog om wingerd wondbeskerming deur Trichoderma (T.) spp. te verbeter en „n meer volledige begrip van die faktore en meganismes betrokke by biologiese beheer te ontwikkel. Die effek van die tydsberekening van snoei (vroeg of laat) en vyf behandelingstye van die biobeheer agent na snoei op die kolonisering van snoeiwonde deur T. atroviride en T. harzianum is bepaal. Chenin blanc en Cabernet Sauvignon wingerde is gesnoei gedurende Julie (vroeg) en Augustus (laat) in 2011 en 2012, en snoeiwonde is behandel met Trichoderma spp. suspensies op verskillende tydspunte (0, 6, 24, 48 en 96 ure) na snoei. Wond-kolonisering was afhanklik van die fisiologiese toestand van die wingerdstok gedurende snoei vir albei kultivars. Gedurende die 2012 seisoen was wond-kolonisering ewe hoog vir albei snoeitye op Chenin blanc. Dit is verklaar deur hoë reënval en humiditeit gedurende daardie seisoen. Die aanwending van biobeheer agente 6 ure na snoei het konsekwent hoë kolonisering deur Trichoderma spp. tot gevolg gehad op albei kultivars en albei snoeitye. In albei kultivars is wondinfeksie as gevolg van natuurlike inokulum hoër gewees in wonde gemaak gedurende laat winter as in wonde wat vroeër in die seisoen gemaak is. Die effek van konidia formulasie in voeding (glukose, gisekstrak en urea) en bioverbetering (chitien en sel-vrye kultuurfiltraat) toevoegings op snoeiwond-kolonisering deur T. atroviride is ook ondersoek. Voeding toevoegings het die omvangs van snoeiwond-kolonisering deur T. atroviride vergroot in vergelyking met ongewysigde konidia suspensies gedurende „n glashuis studie. Die toevoegings, sowel as Garrison, „n snoeiwond verf wat „n swamdoder bevat, en Eco77®, „n geregistreerde T. harzianum biobeheer produk, is getoets in veldproewe vir wondbeskerming teen infeksie deur Phaeomoniella (Pa.) chlamydospora. In 2011 is die patogeen geïnokuleer „n dag na snoei en al die Trichoderma spp. behandelings het infeksie verminder met 75% tot 90% op Thompson Seedless. Beheer was minder suksesvol op Chenin blanc, waar slegs 40% tot 74% beheer behaal is. In 2012 is die proef uitgevoer slegs op Chenin blanc en die patogeen is geïnokuleer teen intervalle van 1, 3 en 7 dae na snoei. Wondbeskerming by die Trichoderma behandelinge was die hoogste wanneer wonde sewe dae na snoei geïnokuleer is met Pa. chlamydospora. Twee konidia formulasies, „n kultuurfiltraat wat bestaan het uit „n chitien-gebaseerde medium en „n kombinasie van gisekstrak, urea en glukose het deurlopend die effektiwiteit van biobeheer verbeter. Hierdie formulasies het Pa. chlamydospora infeksie verminder tot soortgelyke vlakke behaal deur Garrison. Die integrasie van chemiese- en biobeheer in wondbeskerming kan onmiddelike en langtermyn wondbeskerming bied, maar is beperk deur die sensitiwiteit van die biobeheer agent teen swamdoders. Benzimidazole-weerstandbiedende Trichoderma isolate is ontwikkel deur gamma-bestraling van die wilde-tipe isolate van T. atroviride (UST1 en UST2) en T. harzianum (T77). Mutante van UST1 en UST2 het soortgelyke biologiese fiksheid getoon as die wilde-tipe en het hul in vitro antagonistiese aktiwiteit teen wingerd stampatogene behou, terwyl die mutant van T77 verminderde fiksheid getoon het en nie meer antagonisties teen patogene was nie. Die wilde-tipe, UST1, en sy mutant is apart en in kombinasie met thiofanaatmetiel en carbendazim, respektiewelik, getoets vir die vermoë om snoeiwonde te beskerm teen Pa. chlamydospora. Die kombinasie van die UST1 mutant met carbendazim was die mees effektiewe behandeling en het die hoogste vermindering in Pa. chlamydospora infeksie gelewer (70 tot 93% beheer). As „n beginpunt om die belang van Trichoderma-wingerd interaksies in snoiewondbeheer te bepaal, is die invloed van T. atroviride en Eutypa (E.) lata op somatiese selkulture van wingerd vergelyk. Die effek van dié behandelings op ensieme in die fenielpropanoïedweg en patogenese-verwante (PR) proteïene is bepaal deur intydse PKR (real time PCR) van die korresponderende gene oor „n 48 uur tydperk. Die swam-afkomstige ontlokkers het „n hipersensitiewe-tipe reaksie in die selkulture ontlok, wat tot „n afname in sellewensvatbaarheid gelei het. Ontlokkers afkomstig van beide swamme het dieselfde gene aangeskakel en het induksie van fenielalanien ammoniak-liase (PAL), 4 kumaroïel Ko-A ligase (CCo-A), stilbeen sintase (STS), chitienase klas IV (CHIT IV), PR 3 en PR 4 veroorsaak en „n onderdrukking in chalkoon sintase (CHS) gene tot gevolg gehad. Hoër uitdrukking van PAL en CHIT IV in selkulture behandel met die T. atroviride ontlokker het gelei tot „n beduidende hoër (P < 0.05) totale fenoolinhoud en chitienolitiese aktiwiteit in selkulture in vergelyking met selkulture wat behandel is met die E. lata ontlokker. Die reaksie van die selkulture op die T. atroviride ontlokker dui daarop dat die induksie van wingerd weerstandbiedenheid betrokke mag wees in wond biobeheer. Die rol van sekondêre metaboliete geproduseer deur Trichoderma spp. wat gebruik word in snoeiwond beheer is ook ondersoek. „n Vlugtige antimikrobiese verbinding, 6-pentiel α-pyroon (6PP) is geïsoleer en bepaal om die hoof sekondêre metaboliet afkomstig vanuit die T. atroviride (UST1 en UST2) en T. harzianum (T77) isolate te wees. Hierdie metaboliet is betrokke by inhibisie van miselium groei, spoor en konidium ontkieming van E. lata, Neofusicoccum (N.) australe, N. parvum en Pa. chlamydospora. Die produksie van 6PP is geïnduseer deur die T. atroviride in wingerd hout ekstrak te kweek. In die geval van UST1, is die 6PP konsenstrasie verdubbel deur die isolaat met saam met N. parvum te kweek. Hierdie resultaat is „n aanduiding dat 6PP betrokke is in die Trichoderma-patogeen interaksie op snoeiwonde. Die resultate van hierdie studie het nuwe inligting met betrekking tot die aanwending van Trichoderma-gebaseerde snoeiwond produkte verskaf. Die beste tyd vir aanwending van sulke produkte was 6 ure na snoei. Die formulasie van konidia suspensies van Trichoderma spp. met voeding toevoegings en in proteïen ekstrakte van die biobeheer agent het potensiaal getoon in die vermindering van variasie in wondbeskerming deur biobeheer agente. Verdere navorsing sal nodig wees om kommersiële produkte te ontwikkel. Die aanwending van „n swamdoder saam met Trichoderma spp. in die wingerd is belowend om beheer te verbeter, maar het meer proewe nodig voor kommersialisering. Hierdie studie is die eerste om wingerd beskerming gene wat deur Trichoderma spp. geaktiveer word aan te meld. Laasgenoemde, saam met die beskrywing van die hoof sekondêre metaboliete wat deur hierdie Trichoderma spp. geproduseer word, dra by tot „n meer volledige begrip van die meganismes betrokke by die komplekse interaksie tussen die biobeheer agent, die gasheer en die patogeen.

Thesis (MScAgric (Plant Pathology))--Stellenbosch University, 2008.
In recent years, several studies have conclusively shown that numerous pathogens, including several species in the Botryosphaeriaceae, Phomopsis, Phaeoacremonium, as well as Phaeomoniella chlamydospora and Eutypa lata, contribute to premature decline and dieback of grapevines. These pathogens have the ability to infect grapevines through pruning wounds, which leads to a wide range of symptoms developing that includes stunted growth, cankers and several types of wood necrosis. Pruning wounds stay susceptible for 2 to 16 weeks after pruning and sustained levels of pruning wound protection is therefore required. The aims of this study were to (i) evaluate the ability of several biological agents to protect pruning wounds, (ii) characterise unknown Trichoderma strains and identify their modes of action and (iii) determine the optimal time of season for biological agent application. Several biological agents were initially evaluated in a laboratory for their antagonism against trunk disease pathogens. The best performing control agents were tested in a field trial conducted on Merlot and Chenin blanc vines in the Stellenbosch region. Spurs were pruned to three buds and the fresh pruning wounds were treated with benomyl as a control treatment, Trichoderma-based commercial products, Vinevax® and Eco77®, Bacillus subtilis, and Trichoderma isolates, USPP-T1 and -T2. Seven days after treatment the pruning wounds were spray inoculated with spore suspensions of four Botryosphaeriaceae spp. (Neofusicoccum australe, N. parvum, Diplodia seriata and Lasiodiplodia theobromae), Eutypa lata, Phaeomoniella chlamydospora and Phomopsis viticola. After a period of 8 months the treatments were evaluated by isolations onto potato dextrose agar. Trichodermabased products and isolates in most cases showed equal or better efficacy than benomyl, especially USPP-T1 and -T2. Moreover, these isolates demonstrated a very good ability to colonise the wound tissue. The two uncharacterised Trichoderma isolates (USPP-T1 and USPP-T2), which were shown to be highly antagonistic toward the grapevine trunk disease pathogens, were identified by means of DNA comparison, and their ability to inhibit the mycelium growth of the trunk disease pathogens by means of volatile and non-volatile metabolite production studied. The two gene areas that were used include the internal transcribed spacers (ITS 1 and 2) and the 5.8S ribosomal RNA gene and the translation elongation factor 1 (EF). The ITS and EF sequences were aligned to published Trichoderma sequences and the percentage similarity determined and the two Trichoderma isolates were identified as Trichoderma atroviride. The volatile production of T. atroviride isolates was determined by placing an inverted Petri dish with Trichoderma on top of a dish with a pathogen isolate and then sealed with parafilm. Trichoderma isolates were grown for 2 days on PDA where after they were inverted over PDA plates containing mycelial plugs. The inhibition ranged from 23.6% for L. theobromae to 72.4% for P. viticola. Inhibition by non-volatile products was less than for the volatile inhibition. Inhibition ranged from 7.5% for N. parvum to 20.6% for L. theobromae. In the non-volatile inhibition USPP-T1 caused significantly more mycelial inhibition than USPP-T2. The timing of pruning wound treatment and subsequent penetration and colonisation of the wound site was also determined. One-year-old canes of the Shiraz and Chenin blanc cultivars were grown in a hydroponic system, pruned and spray treated with a spore suspension of Trichoderma atroviride (USPP-T1) as well as a fluorescent pigment. On intervals 1, 3, 5 and 7 days after treatment, the distal nodes were removed and dissected longitudinally. From the one half, isolations were made at various distances from the pruning surface, while the other half was observed under ultra-violet light to determine the depth of fluorescent pigment penetration. Shortly after spray-inoculation of a fresh pruning wound, Trichoderma was isolated only from the wound surface and shallow depths into the wound (2 to 5 mm). One week after inoculation, Trichoderma was isolated at 10 mm depths, and after 2 weeks, at 15 mm depths. Fluorescent pigment particles were observed to a mean depth of 6 mm, which suggests that initial isolation of Trichoderma at these depths was resultant of the physical deposition of conidia deeper into the pruning wound tissue, whereas the isolation of Trichoderma from deeper depths might be attributed to colonisation of grapevine tissue. In a vineyard trial, fluorescent pigment was spray-applied to pruning wounds of Shiraz and Chenin blanc grapevines during July and September at intervals 0, 1, 3, 7 and 14 days after pruning. One week after treatment, the distal nodes were removed and dissected longitudinally. Each half was observed under UV light and the pigment penetration measured. For Chenin blanc and Shiraz, July pruning wounds showed significant deeper penetration of the pigment than pruning wounds treated in September. Moreover, pruning wounds made in September showed pigment particles in longitudinal sections up to 1 day after pruning, whereas wounds made in July showed pigment particles up to 3 days in the xylem vessels. These findings suggest that the best time for application of a biological control agent should be within the first 24 hours after pruning.

Complete vineyard floor cover cropping and root pruning (RP) were evaluated for their ability to regulate excessive vegetative growth and improve berry and wine composition of ‘Cabernet Sauvignon’ (Vitis vinifera L.). Treatments were: tall fescue (Festuca arundinacea Shreb.) ‘KY-31’ and ‘Elite II’, hard fescue (Festuca ovina L.) ‘Aurora Gold’, perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata L.), and an under-trellis herbicide strip combined with KY-31fescue interrows. Compared to herbicide strip/non-root pruned (NRP), Elite II fescue reduced vine pruning weight (kg/vine) 28%, individual cane weight (g) 20%, and canopy leaf layer number 25%. KY-31 fescue/RP lowered vine pruning weights 29% compared to an 8% reduction in pruning weights of vines grown in herbicide strip/NRP plots from 2005 to 2010. KY-31 fescue produced the greatest biomass and stand density. With the exception of a yield reduction in vines grown with KY-31 fescue in 2006, cover crops minimally decreased grape yield. Yearly climatic variation had a greater effect on berry weight and composition (pH, TSS, TA) than did treatments. Limited treatment differences detected in chemical compounds by gas chromatography–mass spectrometry (GC-MS) analysis in wines made from treatment vines in 2010 were correlated to descriptive sensory terms. Cover crop water use, as evapotranspiration, determined by mini-lysimeter (ML), ranged from 3.28 mm/d for KY-31 fescue to 1.52 mm/d for herbicide-treated plots. In 2008, root biomass of vines grown on KY-31 fescue/RP was increased at the 60 to 80 and 80 to 100 cm soil depths compared to root biomass of KY-31 fescue/NRP vines at those depths. Cover crops minimally impacted vine water potential (ΨPD, Ψmd, Ψstem) and grapevine nitrogen levels relative to the herbicide strip, indicating that the grasses were not overly competitive with grapevines. Root pruning and complete vineyard floor cover crops favorably reduced grapevine vegetative growth, although treatment effects diminished over time, possibly in response to redistribution of grapevines’ roots and climatic variation at the site.
Ph. D.

Thesis (MScAgric)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Grapevine trunk diseases are responsible for reduced wine and table grape production world-wide. Trunk disease infections are caused by xylem-inhabiting pathogens which include species of Botryosphaeriaceae, Diatrypaceae, Hymenochaetales and Diaporthales, as well as Phaeomoniella chlamydospora and Phaeoacremonium spp. Winter pruning wounds are regarded as the main infection-sites for trunk disease pathogens. However, the role of sucker wounds as portals of trunk disease infections has been minimally investigated. Knowledge of the potential role of grapevine trunk pathogen infections that occur through sucker wounds is important for better wound protection strategies. The aim of this study was to determine the role of grapevine sucker wounds as portals of entry for trunk disease pathogens and to assess the use of Trichoderma spp. for sucker wound protection. The susceptibility of sucker wounds to different trunk disease pathogens was assessed from natural as well as artificial infections. In addition the duration of sucker wound susceptibility in the field was also ascertained. Sucker wounds were sampled from three wine and two table grape vineyards during 2011 and 2012 in the Western Cape province of South Africa. Thereafter, fungal isolations were made from 161 sucker wounds and the cultures were identified based on cultural and morphological characteristics as well as the internal transcribed spacer regions and 5.8S ribosomal RNA gene. Sixty-two percent of the wounds were naturally infected by at least one of the trunk pathogens. Phomopsis (Po.) viticola (46%; 18%), Diplodia (D.) seriata (30%; 9%) and Phaeomoniella (Ph.) chlamydospora (27%; 5%) were the most predominant trunk disease pathogens isolated from sucker wounds of field wine and table grape cultivars, respectively. Lower incidences of Phaeoacremonium aleophilum (18%), Eutypella sp. (3%), Cryptovalsa ampelina (2%), Diplodia sp. (1%) and Neofusicoccum australe (1%) were obtained, however, only from wine grapes. Sucker wounds on 1-year-old potted grapevine plants of Chardonnay cultivar were inoculated with spore suspensions of Eutypa lata, N. parvum, Pa. aleophilum, Ph. chlamydospora and Po. viticola in the glasshouse. After 4 months all the inoculated pathogens could be re-isolated at the following incidences: N. parvum (85%), Ph. chlamydospora (75%), Po. viticola (65%), Pa. aleophilum (55%) and E. lata (45%). Sucker wound susceptibility was further ascertained under field conditions on 12-year-old Cabernet Sauvignon vines by artificial inoculation of the same pathogen species. After 5 months three pathogens could be re-isolated at the following incidences: Po. viticola (65%), N. parvum (32.5%) and Ph. chlamydospora (7.5%). The duration of susceptibility of field sucker wounds to Ph. chlamydospora was assessed for a period of 4 weeks. The wounds remained susceptible for 4 weeks with a decline in susceptibility after one week. This study showed that sucker wounds are susceptible to the major trunk disease pathogens and thus could play an important role in grapevine trunk disease epidemiology. In the second part of this thesis a possible management strategy to prevent infections of sucker wounds was investigated. The use of Trichoderma (T.) harzianum against two trunk pathogens on sucker wounds was tested in the field. Additionally the sensitivity of T. harzianum and T. atroviride was tested in vitro against 16 fungicides that are used to control powdery mildew, downy mildew, Botrytis rot and Phomopsis cane and leaf spot. In October 2012, sucker wounds were made on 1-year-old wood of Cabernet Sauvignon and spray-treated with Eco-77® immediately after desuckering, and then inoculated with spore suspensions of either Ph. chlamydospora or Po. viticola after 24 hours. After 5 months, isolations were made from the sucker wounds to evaluate the efficacy of the Trichoderma treatment. Trichoderma harzianum reduced the incidence of Ph. chlamydospora by 66.65%. Although the incidence of Po. viticola was reduced by 15.37%, it was not significantly different from the control treatment. The inhibition of mycelial growth and conidial germination of T. harzianum and T. atroviride were screened against 16 fungicides. The fungicides were applied at 0, 0.25, 0.5, 1 and 2 times the recommended dosages. Systemic fungicides boscalid, metrafenone and trifloxystrobin, as well as contact fungicides quinoxyfen and meptyldinocap were least toxic to Trichoderma spp. isolates. For the conidial germination assay, boscalid, trifloxystrobin, penconazole and metrafenone (systemic) plus quinoxyfen and folpet (contact) were compatible with Trichoderma spp. These fungicides were regarded as being compatible with Trichoderma spp. isolates because they gave mean percentage inhibitions of less than 50% at all the tested dosages. Spiroxamine and pyrimethanil gave the highest mean percentage inhibitions for both mycelial inhibition and conidial germination. The findings of this study showed that T. harzianum can protect sucker wounds against Ph. chlamydospora in the field. Furthermore, some fungicides applied for the control of powdery mildew and Phomopsis cane and leaf spot can be alternatively or simultaneously applied with T. harzianum and T. atroviride, however, this will have to be verified with field trials.
AFRIKAANSE OPSOMMING: Wingerd stamsiektes is wêreldwyd verantwoordelik vir verminderde wyn- en tafeldruif produksie. Stamsiektes word veroorsaak deur patogene wat in die xileem voorkom, insluitend verskeie spesies in die Botryosphaeriaceae, Diatrypaceae, Hymenochaetales en Diaporthales, asook Phaeomoniella chlamydospora en Phaeoacremonium spp. Winter snoeiwonde word beskou as die hoof bron van infeksies vir stamsiekte patogene. Die rol van suierwonde as poorte van infeksie vir stamsiektes is nog nie goed bestudeer nie. Kennis van die potensiële rol van wingerd stamsiekte patogeen infeksies wat deur suierwonde plaasvind is belangrik vir die formulasie van beter wondbeskerming strategieë. Die mikpunt van hierdie studie was om die rol van suierwonde as ingangsportale vir wingerd stamsiekte patogene te bepaal en om die gebruik van Trichoderma spp. vir suierwond beskerming te evalueer. Die vatbaarheid van suierwonde vir verskillende stamsiekte patogene is geëvalueer vanuit natuurlike, sowel as kunsmatige infeksies. Die duur van suierwond vatbaarheid in die veld is ook bepaal. Suierwonde is versamel vanuit drie wyn- en twee tafeldruif wingerde gedurende 2011 en 2012 in die Wes Kaap provinsie van Suid Afrika. Hierna is swam isolasies gemaak vanuit 161 suierwonde en die kulture is geïdentifiseer volgens kultuur en morfologiese kenmerke, sowel as die interne transkribeerde spasieerders en 5.8S ribosomale RNA geen. Twee-en-sestig persent van die wonde was geïnfekteer deur ten minste een van die stamsiekte patogene. Phomopsis (Po.) viticola (46%; 18%), Diplodia (D.) seriata (30%; 9%) en Phaeomoniella (Ph.) chlamydospora (27%; 5%) was die mees algemene stamsiekte patogene wat, respektiewelik, vanuit die wyn- en tafeldruif kultivars verky is. Laer hoeveelhede Phaeoacremonium aleophilum (18%), Eutypella sp. (3%), Cryptovalsa ampelina (2%), Diplodia sp. (1%) en Neofusicoccum australe (1%) is verkry, en slegs vanaf wyndruiwe. Suierwonde op 1-jaar oue Chardonnay wingerdplante in potte is in die glashuis geïnokuleer met spoorsuspensies van Eutypa lata, N. parvum, Pa. aleophilum, Ph. chlamydospora en Po. viticola. Na 4 maande kon al die geïnokuleerde patogene her-isoleer word teen die volgende hoeveelhede: N. parvum (85%), Ph. chlamydospora (75%), Po. viticola (65%), Pa. aleophilum (55%) en E. lata (45%). Suierwond vatbaarheid is verder geëvalueer onder veld kondisies op 12-jaar oue Cabernet Sauvignon plante deur kunsmatige inokulasie van die selfde patogeen spesies. Na 5 maande kon drie patogene her-isoleer word teen die volgende hoeveelhede: Po. viticola (65%), N. parvum (32.5%) en Ph. chlamydospora (7.5%). Die duur van vatbaarheid van suierwonde teen Ph. chlamydospora in die veld is geevalueer oor ‘n periode van 4 weke. Die wonde het vatbaar gebly vir 4 weke met ‘n afname in vatbaarheid na ‘n week. Hierdie studie demonstreer dat suierwonde vatbaar is vir die hoof wingerd stamsiektes en dus ‘n belangrike rol in die epidemiologie van wingerd stamsiektes kan speel. In die tweede deel van hierdie tesis is ‘n moontlike bestuurs-strategie ondersoek om infeksie van suierwonde te verhoed. Die gebruik van Trichoderma (T.) harzianum teen twee stampatogene op suierwonde is getoets in die veld. Verder is die in vitro sensitiwiteit van T. harzianum en T. atroviride getoets teen 16 fungisiedes wat gebruik word in die beheer van poeieragtige meeldou, donsskimmel, Botrytis vrot en Phomopsis streepvlek. Gedurende Oktober 2012 is suierwonde gemaak op 1-jaar oue hout van Cabernet Sauvignon en onmiddelik behandel met Eco-77® na suiering. Wonde is dan geïnokuleer met spoorsuspensies van óf Ph. chlamydospora óf Po. viticola na 24 uur. Na 5 maande is isolasies gemaak vanaf suierwonde om die doeltreffendheid van van die Trichoderma behandeling te evalueer. Trichoderma harzianum het die voorkoms van Ph. chlamydospora met 66.65% verminder. Alhoewel die voorkoms van Po. viticola verminder is met 15.37%, was dit nie ‘n beduidende verskil in vergelyking met die kontrole behandeling nie. Die inhibisie van miselium groei en konidia ontkieming van T. harzianum en T. atroviride is getoets teen 16 fungisiedes. Die fungisiedes is aangewend teen 0, 0.25, 0.5, 1 en 2 keer die aanbevole dosisse. Sistemiese fungisiedes boscalid, metrafenone en trifloxystrobin, sowel as kontak fungisiedes quinoxyfen en meptyldinocap was die minste toksies teen Trichoderma spp. Gedurende die konidia ontkiemingstoets was boscalid, trifloxystrobin, penconazole en metrafenone (sistemies) en quinoxyfen en folpet (kontak) versoenbaar met Trichoderma spp. Die fungisiedes is beskou as bruikbaar met Trichoderma spp. isolate omdat hulle gemiddelde persentasie inhibisies van minder as 50% teen al die getoetste dosisse gelewer het. Spiroxamine en pyrimethanil het die hoogste gemiddelde persentasie inhibisie gelewer vir beide die miselium inhibisie en konidia ontkieming. Die bevindings van hierdie studie het gewys dat T. harzianum suierwonde kan beskerm teen Ph. chlamydospora in die veld. Verder sou sommige fungisiedes wat aangewend word vir die bestuur van poeieragtige meeldou en streepvlek moontlik alternatiewelik of gelyktydig met T. harzianum en T. atroviride aangewend word, alhowel dit met veldproewe bevestig moet word.

Mestrado Vinifera EuroMaster - Instituto Superior de Agronomia
Three different pruning methods were used as a model system to challenge fundamental principles in viticulture. Different viticultural and physiological parameters of field grown Chardonnay, Sauvignon blanc, Chenin blanc and Syrah have been quantified, analysed and compared; main focus was on the comparison of ratios between and amongst vegetative and reproductive parameters. Changes in grapevine morphology due to the pruning system as already described in literature could be proofed; number of buds left at winter-pruning is “correlated” with the number of shoots, leaves and bunches formed during the next year. Shoot length, internode length, leaf size and bunch mass are correlated inversely to the number of remaining winter buds. Source:sink relationship has been affected by pruning method due to changes in size and priority of the source and sink organs, which also affected carbon allocation as well as plant biomass development. Impacts on the rachis development have been found, impacting on the % share of berries on a bunch and the ratio rachis length to rachis mass. Alternative pruned vines seemed to have more sanitary problems and appeared not to be adapted for high quality grape production. Almost no parameter or ratio was stable when changing pruning system; indicating the difficulty of imposing absolute numbers and use them as a recipe for decision making in viticulture

A videira Itália (Vitis vinifera L.) é a cultivar de uva fina de mesa mais consumida no Brasil, sendo o Estado de São Paulo um dos principais produtores. Em função da diversidade climática presente em diferentes regiões paulistas, ocorre variações na duração do ciclo de produção da videira. Além disso, podas efetuadas em diferentes épocas na mesma região podem alterar a duração do ciclo. No momento da comercialização, a qualidade dos cachos é fundamental, sendo o tamanho das bagas, componente valorizado pelos consumidores. Uma das alternativas para incrementar o tamanho das bagas é o uso de biorreguladores. Com o objetivo de avaliar o desenvolvimento da videira Itália em clima tropical de altitude (Cwa) em diferentes épocas de poda e aplicação isolada ou conjugada de concentrações dos biorreguladores GA3 e CPPU sobre a qualidade dos cachos, dois experimentos foram realizados: O primeiro experimento avaliou seis ciclos de produção (poda-colheita) em dois talhões, sendo três ciclos por talhão, denominados de poda de inverno, poda de verão e poda de primavera. Realizaram-se avaliações visuais semanais a partir da poda até a colheita registrando-se a duração em dias do ciclo de produção e dos períodos poda-brotação, brotação-florescimento, florescimento-veraison e veraison-colheita. O crescimento de ramos, qualidade de produção e somatório térmico em graus-dia (GD) também foi realizado para todos os ciclos. O delineamento foi o inteiramente casualizado, com 25 repetições, sendo a unidade experimental constituída por uma única planta. O segundo experimento avaliou o efeito de concentrações de ácido giberélico (GA3) isolado ou conjugado com forchlorfenuron (CPPU), aplicados em cachos de uva Itália em três ciclos de produção, aos 25 dias após o florescimento em delineamento experimental inteiramente casualizado em fatorial 4X4 (0, 10, 20 e 30 mg.L-1 GA3 X 0, 5, 10 e 15 mg.L-1 CPPU) com oito repetições para o primeiro ciclo e fatorial 3X3 (0, 20 e 30 mg.L-1 GA3 X 0, 10 e 20 mg.L-1 CPPU) com dez repetições para o segundo e terceiro ciclos. Pelos resultados obtidos pode-se concluir que a duração dos ciclos de produção da videira Itália é influenciada pela época de poda. Podas efetuadas na primavera tendem a diminuir a duração do ciclo de produção, enquanto podas realizadas no verão tendem a aumentá-lo. O período do florescimento até o início da maturação das bagas (veraison) possui maior influência na duração do ciclo de produção. Utilizando-se de temperatura-base inferior de 10°C e superior de 30°C, o índice de somatório térmico em graus-dia (GD) é ajustado para período florescimento- veraison. Não há interações entre GA3 e CPPU para todos os ciclos estudados, porém a associação de 20 mg.L-1 de GA3 com 10 mg.L-1 de CPPU, aplicado durante o estádio de ervilha melhora a qualidade de cachos.
Itália grapevine (Vitis vinifera L.) is the most consumed grapevine for fresh market in Brazil, with the State of São Paulo as the major producer. As a result of climate diversity through different regions of this State, grapevine production cycle varies widely. Besides, pruning in different periods of the year in the same region may alter the cycle duration. The cluster quality is determinant for commercialization, with berry size being highly valued by consumers. An alternative to improve berry size is the use of growth regulators. Two experiments were performed. Firstly, Itália grapevine development in humid subtropical climate (Cwa) was evaluated after pruning in different seasons. Secondly, cluster quality was evaluated after application of the growth regulators GA3 and CPPU at increasing concentrations, isolated or in association. The first experiment comprised six production cycles (pruning-harvest) in two experimental areas (three cycles per area), respectively, winter, summer and spring prunings. Visual evaluations were weekly performed from pruning to harvest, computing production cycle duration and intervals pruning-budburst, budburst-flowering, flowering-veraison and veraison-harvest. Cordon growth, fruit quality and determinate the degree-days were also evaluated for all periods. Experimental design was completely randomized with 25 replicates and one plant as plot. In the second experiment, gibberellic acid (GA3) and forchlorfenuron (CPPU) were applied isolated or in association on Itália grapevine clusters in three production cycles 25 days after flowering. Experimental design was a completely randomized 4X4 factorial (0, 10, 20 and 30 mg.L-1 GA3 X 0, 5, 10 and 15 mg.L-1 CPPU) with eight replicates for the first cycle and 3X3 factorial (0, 20 and 30 mg.L-1 GA3 X 0, 10 and 20 mg.L-1 CPPU) with ten replicates for the others cycles. Itália grapevine production cycle varies depending on pruning moment. Spring pruning usually decreases cycle duration while summer pruning increases the cycle duration. Flowering- veraison interval corresponds to the longest period of the production cycle regardless of pruning moment. Considering inferior and superior base temperatures of 10 and 30°C, degree-days was adjusted for flowering-veraison interval. There was no interaction between growth regulators GA3 and CPPU in all production cycles evaluated. The application of GA3 at 20 mg.L-1 associated with CPPU at 10 mg.L-1 in the pea stage improves cluster quality.

One red and one white cultivar of winegrapes grown in Southern Arizona was pruned to four different methods. The red cultivar was 'Merlot' and the white was 'Sauvignon Blanc'. The pruning methods were 2 bud spur, 4 bud spur, cane and basal buds only. The basal bud treatment was eliminated for 'Sauvignon Blanc'. The 4 bud spur method resulted in significantly greater yield when compared to the other methods. Fruit produced from the basal bud only treatment resulted in fruit that was significantly greater in pH and acid content. The 'Sauvignon Blanc' cultivar had significantly higher yield with cane pruning with no difference in fruit quality.

Effects of trellising on water use, absorption of photosynthetically active radiation (PAR, 400 to 700 nm wavelength) by foliage and potentially by fruit, fruit composition, and yield were studied in 1988 under semi-arid conditions on field-grown Vitis vinifera L. 'Petite Sirah' grapevines in a mature vineyard. The positioning of shoots on trellises resulted in canopies that were (1) positioned vertically (vertical canopy), (2) positioned in a "V" pattern with sides inclined 60° from horizontal (inclined canopy), and (3) inclined toward the vineyard floor (standard canopy). Seasonal water use values determined from neutron scattering data were 393 ± 61, 554 ± 73, and 455 ± 57 mm for the standard, vertical and inclined canopies, respectively. On average, about 50% of seasonal water consumption occurred between fruit set and filling stages for each type of canopy. Average crop factors (ratio of actual to reference crop evapotranspiration) of 0.383, 0.540 and 0.444 were for the period bud burst to harvest for standard, vertical and inclined canopy systems, respectively. The diurnal water use patterns of the three trellising canopies were very similar when measured by either the heat pulse technique or by porometer. The average daily heat pulse velocity (HPV) for selected vertical, inclined and standard canopies for 6 days were 8.77, 7.58 and 6.85 cm h⁻¹, respectively. The HPV technique indicated that the average daily water use of the whole plant was 0.227, 0.192 and 0.137 kg/m² leaf area/d for standard, vertical and inclined canopies, respectively. The daily average transpiration rates as measured by the HPV technique were 32, 31, and 25% higher than the average transpiration rates estimated from porometer data for standard, vertical and inclined canopies, respectively. Stomatal conductances of the vertical and inclined canopies were 20 and 40%, respectively, below that of standard canopy. PAR absorption by foliage during mid-day was highest in the standard trellis, and lowest in the inclined trellis. PAR potentially available for absorption by fruits was lowest in the standard trellis, and highest in the inclined trellis. In both inclined and vertical canopies, the average sunfleck values were 26%, but was only 2% in the standard canopy. Analysis of fruit composition at harvest revealed that total dissolved solids (°Brix) was significantly higher in the inclined trellis than for the vertical trellis or the standard trellis. The inclined trellis resulted in the highest alcohol content of wine. Per vine yields did not differ significantly among the three trellis systems. Overall, the standard trellis was optimum because grapevines consumed less water and produced a shading which protected the fruit from direct solar radiation.

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The experiment was carried out in Santa Rita do Araguaia Goiás, in a commercial orchard settled in the Sperafico Site, with total area of 1,7 ha, placed on BR-364 Rd, Km 372, from Goiânia to Cuiabá. This trial with the grapevine Niagara Rosada was done from October 2007 to October 2008. The aim of the research was to study the characteristics of the cultivar Niagara Rosada (Vitis labrusca L.) undergone ten pruning times in Santa Rita do Araguaia GO. The cycle duration (pruning harvest) varied from 121 to 141 days for the 10 pruning times. The pruning times presented differences in the sum of degree-days needed to complete the cycle in the same site. The pruning times did not affect the form of the bunches significantly. Nevertheless, they affected the size of the bunches significantly, especially pruning time P9 (5/10/2008) with 11,60cm and P10 (5/24/2008). The largest berry diameter was found in the pruning times P1 (10/24/2007) and P2 (11/09/2007), with 18,60mm and 18,0mm respectively, patterns considered appropriate for cultivation of Niagara Rosada . The different pruning times showed influence on soluble solids levels, with the highest average of 18.4 ºBrix for pruning time P8 (4/26/2008). However, there was significant variation for the acidity titratable, and for the Ph, the highest value was 4.0, in pruning times P8, P9 and P10. The highest yield was obtained in pruning times P7 (3/28/2008) with 12,63 t ha and P10 (5/24/2008) with 12,12 t ha. Taking into account the thermal requirements and the cycle of the grapevine Niagara Rosada in Santa Rita do Araguaia, it is possible to estimate the date for each of the phenological sub- periods, as well as to predict harvest time.
O experimento foi desenvolvido no município de Santa Rita do Araguaia Goiás, em pomar comercial instalado no Sítio Sperafico, com área total de 1,7 ha, localizado na rodovia BR-364, km 372 no sentido Goiânia-Cuiabá. A condução do experimento com a videira Niagara Rosada foi durante o período de outubro de 2007 a outubro de 2008. O presente trabalho teve por objetivo estudar as características da cultura da uva Niagara Rosada (Vitis labrusca L.) submetida a dez épocas de poda no município de Santa Rita do Araguaia GO. A duração do ciclo produtivo (poda colheita) variou de 121 a 141 dias para as 10 épocas poda. As épocas de poda apresentaram diferenças no somatório de graus-dia necessários para completar o ciclo no mesmo local. As épocas de podas não afetaram significativamente a forma dos cachos, entretanto, afetaram significativamente o tamanho dos cachos, com maior destaque para as épocas E9 (10/05/08) com 11,60cm e E10 (24/05/08). O maior diâmetro de baga foi encontrado nas podas E1 (24/10/07) e E2 (09/11/07) com médias de 18,60mm e 18,0mm respectivamente, médias consideradas adequadas para a Niagara Rosada. As diferentes épocas de poda exerceram influência sobre os teores de sólidos solúveis, com uma maior média de 17,40 ºBrix para época E8 (26/04/08). Todavia, houve variação significativa acidez titulável, e para o pH, o valor mais elevado foi 4,0, nas podas E8, E9 e E10. A maior produtividade foi verificada para as épocas E7 (28/03/08) com 12,63 t/ha e E10 (24/05/08) com 12,12 t/ha. Conhecendo-se a exigência térmica e o ciclo da videira Niagara Rosada em Santa Rita do Araguaia, é possível estimar a data em que ocorrerá cada um dos subperíodos fenológicos e prever a época de colheita.

An automatic pruning machine is desirable due to the limitations and drawbacks of current labor intensive grapevine pruning methods. Automation mitigates the issue of skilled worker shortages and reduces overall labor cost. To achieve autonomous grapevine pruning accurately and effectively, it is crucial to identify and locate some key features including post, trunk, cordon and cane in order to open/close the cutter and adjust the height of the cutter appropriately. In this thesis, a new method is proposed to automatically identify these features and derive their locations using point clouds. This method combines the advantages of cylinder extraction, density clustering and skeleton extraction for identification purposes. More importantly, it fills the gap of non-uniformed feature extraction in vineyards using point clouds. The results of applying this method to different data sets obtained from vineyards are presented and its effectiveness is demonstrated.
Thesis (M.Eng.Sc.) -- University of Adelaide, School of Mechanical Engineering, 2014.

Mestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do Paraná
The increase in the frequency and intensity of extreme weather events is one of the main effects of climate change, with particularly negative consequences for the development of agricultural activity. As water is one of the most limiting factors in yield, irrigation management is a critical factor for the future in a context of water scarcity. This study aims to implement three irrigation regimes (irrigation deficit with 25% and 50% of crop evapotranspiration (ETc) and full irrigation (100% ETc)) and two pruning systems (unilateral Cordon and Guyot) and evaluate their effects on physiological, agronomic and quality parameters in the Touriga Franca (Vitis vinifera L.) variety, in a commercial vineyard located in the Douro region. Field studies were carried out during 2019 in a commercial organic vineyard, located at Quinta do Romeu (41º53´02´´N, 7º08´00´´W, 326 m altitude) in the Northeast of Portugal. Agronomic, physiological and grape quality parameters were evaluated in the different treatments. The results showed that the plants that received the highest amount of irrigation were the ones that showed the best physiological and agronomic performance. In most of the quality parameters of the musts, no differences were observed between treatments, except for the total soluble solids (TSS) content. The deficit irrigation treatment (25% ETc), pruned in Cordon, showed the lowest values, while the 100% ETc full irrigation treatment pruned in Guyot was the one with the highest values. The results presented are from the first year of trials in a study that will take place over several years. Thus, the conclusions presented are still preliminary.
O aumento da frequência e intensidade dos eventos climáticos extremos é um dos principais efeitos das alterações climáticas, com consequências particularmente negativas no desenvolvimento da atividade agrícola. Sendo a água um dos fatores mais limitantes da produção, a gestão da irrigação é um fator crítico para o futuro num contexto de escassez de água. Este estudo tem como objetivo implementar três regimes de irrigação (deficit de irrigação com 25% e 50% de evapotranspiração da cultura (ETc) e plena irrigação (100% ETc)) e dois sistemas de poda (cordão unilateral e Guyot) e avaliar seus efeitos em parâmetros fisiológicos, agronómicos e de qualidade na variedade Touriga Franca (Vitis vinifera L.), numa vinha comercial localizada na região do Douro. Os estudos de campo foram realizados durante o ano de 2019 em uma vinha orgânica comercial, localizada na Quinta do Romeu (41º53´02´´N, 7º08´00´´W, 326 m altitude) no Nordeste de Portugal. Foram avaliados parâmetros agronômicos, fisiológicos e de qualidade da uva nos diferentes tratamentos. Os resultados mostraram que as plantas que receberam maior dotação de rega foram as que apresentaram um melhor desempenho fisiológico e agronômico. Na maioria dos parâmetros de qualidade dos mostos não se observaram diferenças entre os tratamentos com exceção do teor em sólidos solúveis totais (TSS). O tratamento de rega mais deficitária (25%ETc) podado em cordão foi o que apresentou os menores valores, enquanto o tratamento de rega plena 100%ETc) podado em Guyot foi o que apresentou valores mais elevados. Os resultados apresentados dizem respeito ao primeiro ano de ensaios do estudo que vai decorrer ao longo de vários anos. Assim, as conclusões apresentadas são ainda de caracter preliminar.

Mestrado em Viticultura e Enologia - Instituto Superior de Agronomia / Universidade do Porto
Abstract The main objective of this study was the comparison between mechanical hedging and manual pruning systems regarding the agronomy and physiology of Touriga Nacional variety vines conducted in LYS. The experiment was conducted at Quinta da Aguieira, wine producing region of Dão, property owned by Sociedade dos Vinhos Borges. The mechanical hedging originated a significant higher number of nodes per vine. These vines showed self regulation given that both budburst and fertility index were significantly lower when compared with the obtained with the manual pruning. In the mechanical hedging system the total leaf area registered was significantly higher. A higher number of principal leafs with a smaller area per unit was identified. The secondary leaf area was significantly higher in the manual pruning system. Although these differences between the two systems were identified, no significant differences were found regarding the pre-dawn leaf potential. Sugar accumulation was delayed on hedge pruning, although the berry weight, titratable acidity, anthocyanin concentration and Folin-Ciocalteu índex had shown no siginificant diferences between hedged and manual pruning. Significant differences were found in the sugar content of the must witch was higher in manual pruning. The wine produced from the mechanical hedging system vines showed an alcohol index slightly lower than the one produced from the manual pruning system vines.-------------------------------------No presente trabalho pretendeu-se comparar o efeito da poda mecânica em sebe e da poda manual no comportamento agronómico e fisiológico da casta Touriga Nacional no sistema de condução LYS. Este estudo decorreu na Quinta da Aguieira, propriedade da Sociedade dos Vinhos Borges e localizada na Região Vitivinícola do Dão. A poda em sebe originou uma carga à poda significativamente superior, demonstrando essas videiras autoregulação ao apresentarem uma taxa de abrolhamento e um índice de fertilidade significativamente inferiores comparativamente à poda manual. A poda em sebe apresentou uma maior capacidade produtiva que se pode relacionar com a maior área foliar. O aumento da área foliar deve-se principalmente ao maior número de sarmentos e folhas, estas eram significativamente menores. A poda manual apresentou maior área foliar secundária. A maior área foliar não foi propícia a um stress hídrico pronunciado nem diferenças a esse nível entre modalidades. A evolução da maturação mostrou não existir diferença do peso dos bagos, da acidez total, das antocianas ou do índice de Folin-Ciocalteu entre modalidades. A produção da poda em sebe foi cerca do triplo da poda manual, associada a uma ligeira diminuição do teor alcoólico do vinho mas sem outras alterações da qualidade.