scholarly journals Increasing Tree Complexity and Bearing Potential in Young `Fuji' Apple Trees

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 506E-507
Author(s):  
Marius Huysamer

Under typical South African growing conditions, `Fuji' apple (Malus domestica Borkh.) trees are characterized by strong apical dominance during the first few years after planting. This, together with the current lack of suitable precocious rootstocks and the tip-bearing habit, causes willowy “blind wood” growth with few flowering positions, and delays bearing until the third leaf when a crop of less than 10 tons/hectare can be realized. Promalin (GA4+7 and benzyladenine, Abbott Laboratories) was used in combination with apical meristem defoliation and Agral or Armoblen as surfactant/penetrant to induce sylleptic shoot growth in an effort to increase tree complexity (i.e., branching) without having to resort to pruning, which is dwarfing and delays bearing. The treatments were tested on `Fuji' grafts, 1-year old trees and 2-year old trees in the 1993–1994, 1994–1995, and 1995–1996 seasons, respectively. Concentrations tested were 0, 500, 750, or 1000 ppm, as single or multiple applications in spring. In all trials, randomized, complete block designs were used. Control trees had few, if any, sylleptic shoots or spurs, whereas Promalin in combination with leaf removal or in combination with Armoblen caused significant sylleptic growth to occur. Generally, multiple applications spaced fortnightly, gave best results. Sylleptic shoots were ≈15 cm long, terminated in a reproductive bud, and did not influence the length of the “mother” shoot or the trunk circumference. Based on these results, a combination of multiple applications of 500 ppm Promalin with Armoblen as penetrant, and no leaf removal, is being tested semi-commercially this season.

1994 ◽  
Vol 8 (4) ◽  
pp. 840-848 ◽  
Author(s):  
Chester L. Foy ◽  
Susan B. Harrison ◽  
Harold L. Witt

Field experiments were conducted at two locations in Virginia to evaluate the following herbicides: alachlor, diphenamid, diuron, metolachlor, napropamide, norflurazon, oryzalin, oxyfluorfen, paraquat, pendimethalin, and simazine. One experiment involved newly-transplanted apple trees; the others, three in apple and one in peach trees, involved one-year-old trees. Treatments were applied in the spring (mid-April to early-May). Control of annual weed species was excellent with several treatments. A broader spectrum of weeds was controlled in several instances when the preemergence herbicides were used in combinations. Perennial species, particularly broadleaf species and johnsongrass, were released when annual species were suppressed by the herbicides. A rye cover crop in nontreated plots suppressed the growth of weeds. New shoot growth of newly-transplanted apple trees was increased with 3 of 20 herbicide treatments and scion circumference was increased with 11 of 20 herbicide treatments compared to the nontreated control. Growth of one-year-old apple trees was not affected. Scion circumference of one-year-old peach trees was increased with 25 of 33 herbicide treatments.


HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 691b-691
Author(s):  
Yong-Koc Kim ◽  
Yong-Suk Kim

Experiments were carried out to evaluate some newly devised and conventional methods of grafting using `Fuji' apple trees on M.26/M. prunifolia rootstocks. Out of various methods of grafting, the modified inverted-veneer grafting and the inverted bark grafting showed a complete healing of the grafting union leaving no part of xylem tissue exposed in the air. However, owing to the longer period of growth for the trees grafted by the modified inverted-veneer grafting than the inverted bark grafting during the period of one growing season, the modified inverted-veneer gave slightly better shoot growth than the inverted bark grafting. It was clear that the former two methods were superior to the all other grafting methods, i.e., whip-and-tongue grafting, modified veneer grafting, inverted-veneer grafting, bark grafting, and chip budding in the grafting union healing, shoot growth, and tree form performance.


HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 438a-438
Author(s):  
Michael Parker ◽  
Eric Young

Controlling vegetative growth resulting from a long growing season in the southeast is difficult while trying to promote early fruiting. This study was initiated in 1990 to evaluate higher density leader training techniques, cultivar interactions, and the benefits of pre-plant fumigation on apple replant sites. Another objective was to evaluate these management parameters in four regions with very different climates and elevations. The training techniques evaluated were, weak leader renewal, bending of the leader during the growing season, and partial terminal leaf removal every 10 inches of leader growth (without injuring the apical meristem). The cultivars used were Jonagored, Spur Gala, and Red Fuji, all on Mark rootstock. First and second year branching was not significantly different between the various training techniques. Yields during the third year did not appear to differ between the leader training techniques. Pre-plant fumigation appeared to be beneficial in increasing tree growth in only two of the four sites.


1992 ◽  
Vol 117 (2) ◽  
pp. 271-273 ◽  
Author(s):  
Eric Young

Budbreak and root and shoot extension growth of apple trees (Malus domestics Borkh. MM.111) were affected by exposure to 500 hours of higher temperatures (15, 20, or 30C) during the first, second, or third 500 hours of a 1500-hour, 5C chilling period. Exposure to 15C during the third 500 hours had a significantly positive effect on budbreak, 20C at this time had no effect, and all other treatments had a negative effect on budbreak and new root and shoot growth.


2011 ◽  
Vol 17 (4-5) ◽  
Author(s):  
P. Dremák ◽  
I. Gonda ◽  
Z. Szabó ◽  
J. Nyéki

Summary: On the Experimental Farm of the Debrecen University at Pallag, a factorial experiment has been started at springtime of 2008 on an orchard of 12 year old apple trees ’Idared’ grafts on M 26 understocks. The first factor was the growing system (integrated versus ecological), the second was the intensity of pruning (strong versus moderate thinning of the crown), whereas the third was the method of pruning (shortening versus thinning of individual shoots). Measurements have been concentrated on shoot growth, flower initiation, fruit set and accumulated yield of two successive seasons. The following conclusions are made.– In the ecological growing system, strong thinning proved to be beneficial for growth as well as for fruit bearing. – Strong thinning combined with shortening of shoots diminished yield in the first year, whereasmoderate thinning combined with shortening of shoots caused favourable growth and fruit bearing.– In the ecological growing system, the moderate shoot growth was associated with better flower initiation, which increases the chances of alternate yielding.– According to our results, the flower initiation of the ‘Idared’ was stimulated univocally by the thinning of shoots regardless of the intensity of pruning.The right choice of the intensity and method of pruning is a decisive moment of a successful yield in the ecological apple growing system


HortScience ◽  
1991 ◽  
Vol 26 (7) ◽  
pp. 840-843 ◽  
Author(s):  
Wesley R. Autio ◽  
Duane W. Greene ◽  
Daniel R. Cooley ◽  
James R. Schupp

Increasing the N application rate (in the form NH4NO3 to newly planted `Marshall McIntosh'/M.9 apple (Malus domestica, Borkh.) trees beyond 76 g N per tree per year reduced growth in the first two growing seasons. Peat moss or composted manure mixed into the planting hole of `Royal Gala'/M.26 increased growth in the first growing season after planting. The soil-active fungicides, fosetyl-Al and metalaxyl, increased trunk and shoot growth of `Royal Gala'/M.26 in the first season after planting. Mulching enhanced growth of `Gala'/M.26 only in the third season after planting, a season during which the region experienced a drought. Mulching significantly increased bloom on `Gala'/M.26 2 years after planting. The growth of `Royal Gala'/M.26, `Marshall McIntosh'/M.26, and `Ace Delicious'/M.26 was not affected by planting technique planting by hand in 61-cm augered holes vs. planting with a mechanical tree planter. Chemical names used N-(2,6-dimethyl-phenyl)-N-(methloxyacetyl)alanine methyl ester (metalaxyl); aluminum tris (O-ethyl phosphonate) (fosetyl-Al); 1,1'-dimethyl-4-4'-bipyridinium ion (paraquat); isopropylamine salt of N-(phosphonomethyl) glycine (glyphosate).


1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Dirk Kotzé

As the title indicates this publication is the third issue in a series of reviews. The first issue was subtitled 2010: Development or decline? (2010) and the second was New paths, old promises? (2011). These publications are edited in the Department of Sociology at Wits University as part of its Strategic Planning and Allocation of Resources Committee (SPARC) Programme. The series is intended to be a revival of the South African Review edited by the South African Research Service and published by Ravan Press in the 1980s and early 1990s. Arguably one of the best known of these series was issue seven edited by Steven Friedman and Doreen Atkinson, The Small Miracle: South Africa's negotiated settlement (1994). The latest publication should also be seen as direct competition for the Human Sciences Research Council's (HSRC) regular publication, State of the Nation. The New South African Review 3 is organised into four parts, namely Party, Power and Class; Ecology, Economy and Labour; Public Policy and Social Practice; and South Africa at Large. The four editors introduce each of the sections, consisting of 16 chapters in total. Thebook's format appears to be that of a yearbook but it is not linked to a specific year. It is therefore not in the same category as for example the South African Institute of Race Relations' annual South Africa Survey. The Review is organised around a theme, albeit very general in its formulation, and in the case of the third issue it is also not applicable to all its chapters. At the same time, though, it is not a yearbook as the choice of chapters and their foci are on the latest developments. 


Sign in / Sign up

Export Citation Format

Share Document