Effect of various combinations of trellis, pruning, and rootstock on vigorous Sultana vines

The combined effects of three trellis, three pruning, and three rootstock treatments were tested on vigorous Sultana vines (Vitis vinifera L.) growing in a lighttextured, nematode- and phylloxera-free, virgin soil of the Australian Murray Valley.Vines on Salt Creek rootstock outyielded vines on 1613 C rootstock or on their own roots by about 40 per cent during the first four cropping seasons after planting, which preceded the experiment, and by about 30 per cent during the four seasons of the experiment, because they had more and larger bunches.A wide, high trellis with two cane-wires 1.2 m apart and 1.5 m above ground level, a narrow, high trellis (0.3 m X 1.5 m) and a narrow, low trellis (0.3 m X 1.0 m) were compared. On the wide trellis, the foliage canopy was divided naturally into two halves. In the season following the trellis conversion, vines on the wide trellis yielded slightly better than those on either of the narrow trellises, possibly because there was less mould damage. In the subsequent seasons, the wide trellis was much more productive. lt produced 40 to 50 per cent more crop because the vines had more bunches with more berries per bunch, while the concentration of sugar or acids remained unaltered. The amount of pruning wood was also somewhat greater. For the three pruning treatments, vines were given 126, 196, or 266 nodes (i. e. 9, 14, or 19 canes of 14 nodes each). In the later years of the experiment, the lightest pruning level could not be maintained on the narrow trellis, and pruning weight tended to become smaller. Yield increased disproportionately with increasing nodenumber; a two-fold increase in the number of nodes led to only a 20 per cent increase in yield.There were few interactions between the trellis, pruning, and rootstock treatments. The beneficial effects of wide trellis, Salt Creek rootstock and of light pruning, at least up to the level of 196 nodes per vine, tended to be additive. Thus lightly pruned Sultana vines on Salt Creek rootstock grown on a wide trellis with split canopy produced twice as much fruit as the conventionally treated Sultana, i. e. an own-rooted vine with 126 nodes grown on a narrow, low trellis.lt is concluded that Sultanas benefit from wide trellis through an effect on bud fruitfulness which leacls to more berries per vine, and through better photosynthetic activity which allows f4ll maturation of this increased crop potential. The economic implications of using wicle trellises and Salt Creek rootstock are discussed.Der Einfluß verschiedener Kombinationen von Drahtrahmen, Rebschnitt und Unterlage auf starkwüchsige Sultana-RebenDer vereinte Einfluß von drei Drahtrahmen-Typen und drei Schnittarten auf wurzelechte Sultana-Reben und auf Sultana, gepfropft auf den Unterlagen Salt Creek und 1613 C, die in einem leichten, Nematoden- und Phylloxerafreien Urboden des australischen Murray-Bewässerungsgebietes wuchsen, wurde untersucht. Alle Resultate wurden der Varianzanalyse unterworfen.In den ersten vier Ertragsjahren nach der Pflanzung, die dem Versuch vorausgingen, war der Ertrag von Sultana auf Salt Creek um 40°/o höher als derjenige von wurzelechten oder auf 1613 C gepfropften Reben. In den folgenden vier Versuchsjahren betrug dieser Unterschied etwa 30°/o. Mehr und größere Trauben waren der Grund hierfür.Die drei Drahtrahmen hatten die folgenden Dimensionen: Ein weiter, hoher Rahmen mit zwei Drähten, die mit 1,2 m Abstand 1,5 m über dem Boden angebracht waren; ein enger, hoher Rahmen (0,3 m X 1,5 m) und ein enger, niedriger Rahmen (0,3 m X 1,0 m) mit einem weiteren Draht für das Blattwerk. Am weiten Drahtrahmen teilte sich das Blattwerk spontan in zwei Hälften. In der ersten Vegetationsperiode nach dem Erstellen der Drahtrahmen war der Ertrag am weiten Rahmen etwas besser, vermutlich wegen des geringeren Fäulnisbefalles. In den folgenden drei Vegetationsperioden brachten die Reben am weiten Drahtrahmen um 40 bis 50°/o höhere Erträge, da mehr und größere Trauben vorhanden waren, während Beerengröße, Zucker- und Säuregehalt unverändert blieben. Auch das Gewicht des Schnittholzes war etwas größer. Die Reben wurden zu 9, 14 oder 19 Tragruten von je 14 Knospen, demnach zu 126, 196 oder 266 Knospen, geschnitten. Am engen Drahtrahmen konnte man die höchste Knospenzahl in den letzten Jahren des Versuches nicht erhalten, und auch das Triebgewicht wurde kleiner. Im allgemeinen hatte die Verdopplung der Knospenzahl nur einen 20prozentigen Anstieg im Ertrag zur Folge.Wechselwirkungen zwischen den Behandlungsarten Drahtrahmen, Schnitt und Unterlage kamen nur vereinzelt vor. Die vorteilhaften Einflüsse von weitem Drahtrahmen, Salt Creek-Unterlage und von höheren Knospenzahlen, wenigstens bis zu 196 Knospen je Rebe, waren additiv. Infolgedessen war der Ertrag der zu 196 Knospen geschnittenen Sultana auf Salt Creek und auf weitem Rahmen zweimal so groß wie derjenige der wurzelechten Sultana auf engem Rahmen mit 126 Knospen.Es wird geschlossen, daß Sultanaknospen am weiten Drahtrahmen fruchtbarer sind und daß folglich im nächsten Jahr die Reben mehr Traubenbeeren tragen, die überdies durch Verbesserung der Photosynthese völlig ausreifen können. Die ökonomischen Verhältnisse für den Gebrauch von weiten Drahtrahmen werden diskutiert

The relationship between vegetative and reproductive development in the mango in northern Australia

Vegetative and reproductive growth was recorded on mature mango trees (cultivar Kensington) over two years in northern Australia. There were four vegetative growth flushes during each year, but not all shoots grew during each flush. Observations on the flowering of shoots of known age showed that the older shoots produced most inflorescences. Microscopic examination of terminal buds showed that floral initiation occurred within a month of the commencement of the flowering flush under these tropical conditions. The main vegetative growth flushes occurred prior to flowering between March and May, and during flowering and early fruit development in July and August. © 1986 CSIRO. All Rights Reserved

Assessing the role of EO in biodiversity monitoring: options for integrating in-situ observations with EO within the context of the EBONE concept

The European Biodiversity Observation Network (EBONE) is a European contribution on terrestrial monitoring to GEO BON, the Group on Earth Observations Biodiversity Observation Network. EBONE’s aims are to develop a system of biodiversity observation at regional, national and European levels by assessing existing approaches in terms of their validity and applicability starting in Europe, then expanding to regions in Africa. The objective of EBONE is to deliver: 1. A sound scientific basis for the production of statistical estimates of stock and change of key indicators; 2. The development of a system for estimating past changes and forecasting and testing policy options and management strategies for threatened ecosystems and species; 3. A proposal for a cost-effective biodiversity monitoring system. There is a consensus that Earth Observation (EO) has a role to play in monitoring biodiversity. With its capacity to observe detailed spatial patterns and variability across large areas at regular intervals, our instinct suggests that EO could deliver the type of spatial and temporal coverage that is beyond reach with in-situ efforts. Furthermore, when considering the emerging networks of in-situ observations, the prospect of enhancing the quality of the information whilst reducing cost through integration is compelling. This report gives a realistic assessment of the role of EO in biodiversity monitoring and the options for integrating in-situ observations with EO within the context of the EBONE concept (cfr. EBONE-ID1.4). The assessment is mainly based on a set of targeted pilot studies. Building on this assessment, the report then presents a series of recommendations on the best options for using EO in an effective, consistent and sustainable biodiversity monitoring scheme. The issues that we faced were many: 1. Integration can be interpreted in different ways. One possible interpretation is: the combined use of independent data sets to deliver a different but improved data set; another is: the use of one data set to complement another dataset. 2. The targeted improvement will vary with stakeholder group: some will seek for more efficiency, others for more reliable estimates (accuracy and/or precision); others for more detail in space and/or time or more of everything. 3. Integration requires a link between the datasets (EO and in-situ). The strength of the link between reflected electromagnetic radiation and the habitats and their biodiversity observed in-situ is function of many variables, for example: the spatial scale of the observations; timing of the observations; the adopted nomenclature for classification; the complexity of the landscape in terms of composition, spatial structure and the physical environment; the habitat and land cover types under consideration. 4. The type of the EO data available varies (function of e.g. budget, size and location of region, cloudiness, national and/or international investment in airborne campaigns or space technology) which determines its capability to deliver the required output. EO and in-situ could be combined in different ways, depending on the type of integration we wanted to achieve and the targeted improvement. We aimed for an improvement in accuracy (i.e. the reduction in error of our indicator estimate calculated for an environmental zone). Furthermore, EO would also provide the spatial patterns for correlated in-situ data. EBONE in its initial development, focused on three main indicators covering: (i) the extent and change of habitats of European interest in the context of a general habitat assessment; (ii) abundance and distribution of selected species (birds, butterflies and plants); and (iii) fragmentation of natural and semi-natural areas. For habitat extent, we decided that it did not matter how in-situ was integrated with EO as long as we could demonstrate that acceptable accuracies could be achieved and the precision could consistently be improved. The nomenclature used to map habitats in-situ was the General Habitat Classification. We considered the following options where the EO and in-situ play different roles: using in-situ samples to re-calibrate a habitat map independently derived from EO; improving the accuracy of in-situ sampled habitat statistics, by post-stratification with correlated EO data; and using in-situ samples to train the classification of EO data into habitat types where the EO data delivers full coverage or a larger number of samples. For some of the above cases we also considered the impact that the sampling strategy employed to deliver the samples would have on the accuracy and precision achieved. Restricted access to European wide species data prevented work on the indicator ‘abundance and distribution of species’. With respect to the indicator ‘fragmentation’, we investigated ways of delivering EO derived measures of habitat patterns that are meaningful to sampled in-situ observations