Annual pruning was compared with nonpruning for 8 years and to two biennial pruning treatments for 4 years in a mature full-canopied `Ashley' walnut (Juglans regia L.) orchard. Light penetration and nut distribution through the canopy was improved by pruning. Nut size and percent edible kernel was consistently lower in nonpruned trees than in trees pruned annually or biennially. Yield from annually pruned trees was not significantly different from that of the nonpruned trees because of the removal of fruitful spurs. Yield of biennially pruned trees was similar to annually pruned or nonpruned trees in the year following pruning, but yield was usually greater during years in which trees were not pruned.
William H. Olson, D.E. Ramos, K. Ryugo, and R.G. Snyder
Charles T. Rohla, Michael W. Smith, Niels O. Maness, and William Reid
, respectively. Pest control followed standard commercial practices. Shoot types were: 1) vegetative shoots, 2) fruit-bearing shoots in the terminal position on 1-year-old branches, and 3) fruit-bearing shoots in the lateral position on 1-year-old branches
Charles T. Rohla, Michael W. Smith, and Niels O. Maness
flush in the lateral position on 1-year-old branches, and (4) bearing shoots with a second growth flush primarily in the terminal position. Thirty shoots per tree of each type were tagged at shuck split to monitor return bloom. Shoots of each type were
Reza Amiri, Kourosh Vahdati, Somayeh Mohsenipoor, Mohammad Reza Mozaffari, and Charles Leslie
traits of walnut and found heritabilities above 0.80 for shell thickness, nut and kernel weights and dates of leafing, first pollen shed, pistil receptivity, and harvest. The heritability was above 0.39 for lateral bearing, shell seal, percent light
Michael W. Smith, Charles T. Rohla, and Niels O. Maness
types: 1) vegetative shoots, 2) bearing shoots without a second growth flush in the terminal position on 1-year-old branches, 3) bearing shoots without a second growth flush in the lateral position on 1-year-old branches, and 4) bearing shoots that were
Saadat Sarikhani Khorami, Kazem Arzani, Ghasem Karimzadeh, Abdolali Shojaeiyan, and Wilco Ligterink
temperature for 1 month ( Zeneli et al., 2005 ). Nut and kernel weight were determined, using a digital balance. Kernel percentage was calculated by kernel weight/nut weight × 100. Lateral-bearing habit was measured based on the percentage of current season
Michael E. Tarter and Stefano Poni
highly variable in form, ranging from a bunch-like structure rivaling the main axis in size, all the way down through smaller sizes to just a tendril.” For the purposes of our studies, wings were defined as lateral arms originating from the peduncle
Duane W. Greene and Wesley R. Autio
Benzyladenine (BA) stimulated lateral branching on young apple (Malus domestica Borkh.) trees at concentrations as low as 100 mg·liter-1. BA reduced lateral shoot length indirectly through increased intersboot competition, whereas daminozide reduced lateral shoot growth as a direct effect of the chemical inhibition. Daminozide reduced the number of spurs that were induced by BA to grow into lateral shoots. BA reduced the size of terminal buds on spurs that were stimulated to grow into lateral shoots. When daminozide was included with BA, spur quality was increased, as determined by Increased bud size. The positive effect of daminozide on BA-treated spurs was indirect, and other growth retardants used in combination with BA may be equally effective at improving spur quality. It may not be possible to stimulate lateral branching with BA on young trees just coming into production without causing an unacceptable amount of thinning. However, on bearing `Empire' trees, lateral shoot growth was increased with BA while still achieving an appropriate level of thinning. In general, there was no advantage to applying BA in a split application. Chemical names used: N-(phenylmethyl)-1H-purine-6-amine [benzyladenine (BA)]; butanedioic acid mono(2,2-dimethylhydrazide) (daminozide).
Charles T. Rohla*, Michael W. Smith, Niels O. Maness, and William R. Reid
Whole fruit clusters were collected from three shoot types: terminal and lateral shoots without secondary growth, and shoots with secondary growth. Fruit per cluster was counted and nuts were individually weighed, shelled and graded. Return bloom of the same shoots was measured. Results indicated that cluster size of lateral bearing shoots was negatively related to next year's average kernel weight, nut weight, and kernel percentage. However, only kernel percentage was related to cluster size on terminal bearing shoots, and none of these parameters were related to cluster size on shoots with secondary growth. Cluster size and total kernel weight per shoot were positively related for the three shoot types. Return bloom of terminal shoots was negatively related to cluster size, but cluster size did not affect return bloom of the other shoot types.
Matt J. Stasiak and Teryl R Roper
Inadequate branch production on apple trees can result in reduced bearing surface and problems with tree training. We sought to increase the number of lateral shoots by enclosing the one year old portion of the central leader of two year old `Jonamac', `Red Jonagold', and `Scarlet Gala', apple trees two weeks prior to bud emergence. The bags were then removed when the longest shoots in the bag were approximately 2.5 cm long. After leaf fall the number and length of shoots in the bagged sections were measured. The number of lateral shoots >5 cm in length produced on the bagged sections of the leaders was increased by 3.7. Total lateral growth on the central leader increased by 149 cm per tree. Trunk cross-sectional area, tree height, or production of lateral shoots >5 cm were not affected by bagging. Differences between clear and orange bags were not significant. Bagging appeared to be an efficient means to induce trees to produce lateral branches. The greatest benefit would be to varieties like `Jonamac' and `Red Jonagold' which averaged only 1.7 laterals without bags.