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  • Author or Editor: David Lang x
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Abstract

Vase life of Alstroemeria hybrida ‘Regina’ was longest in inflorescences with secondary and tertiary florets. The presence of additional florets on a cyme decreased the vase life of the primary floret. Maximum flower opening and normal coloration occurred when the primary florets were harvested at the “rolled petal stage”. Cutting Alstroemeria stems above the blanched portion of the stem before placement in water increased water uptake and vase life. When secondary florets were present, leaf removal did not decrease vase life.

Open Access

Traditional sweet cherry (Prunus avium L.) training systems in the United States are based upon vigorous rootstocks and multiple leader vase canopy architectures. The sweet cherry research lab at Washington State University has been investigating the potential of new rootstocks and training systems to improve production efficiency and produce high quality fruit. This paper describes the effects of three rootstocks—Mazzard (P. avium), `Gisela 6', and `Gisela 5' (P. cerasus × P. canescens)—and four training systems—central leader, multiple-leader bush, palmette, and y-trellis—on `Bing' sweet cherry tree vigor, fruit yield and quality over a seven year period. Compared to trees on Mazzard, trees on `Gisela 5' and `Gisela 6' had 45% and 20% lower trunk cross-sectional areas after 7 seasons, respectively. Trees on `Gisela 6' were the most productive, yielding between 13% and 31% more than those on `Gisela 5' and 657% to 212% more than trees on Mazzard, depending on year. Both Gisela rootstocks significantly improved precocity compared to Mazzard, bearing fruit in year 3 in the orchard. Canopy architecture had only moderate effects on tree vigor and fruit yield. Across rootstocks, bush-trained trees were about 25% less productive compared to the other systems, which exhibited similar cumulative yields (102 kg/tree). Fruit weight was negatively and closely (r 2 = 0.84) related to tree yield efficiency (kg·cm–2). Crop value was related positively to fruit yield.

Free access

Abstract

The effects of foliarly applied Cytex (an aqueous seaweed extract) and kinetin on the tuberization process of potato plants were investigated under field conditions. Tuber number was not influenced by foliar applications of Cytex or kinetin, but total yield of ‘Kennebec’ was increased when Cytex (15 ml/liter) was applied during the initial stages of tuberization. This yield advantage was due to an increase in the number of defective tubers. Since sunburn was the dominant defect, improved yields might be possible through the use of Cytex coupled with modified cultural practices. Neither Cytex nor kinetin had any effect on total yield of ‘Russet Burbank’.

Open Access

The new apple (Malus ×domestica Borkh.) cultivar Sciros™, resulting from a cross of 'Gala' with 'Splendour', is marketed internationally from New Zealand. A characteristic of this cultivar is the presence of dense, dark green or black nodules in the fruit cortex, located in close proximity to the five sepal vascular bundles. Nodules are visible as green spots beginning about 40 days after bloom and they continue to develop, reaching a length of up to 8 mm at fruit maturity, although there is considerable variation in their size. Large vascular nodules often develop dark brown centers and reduce the visual quality of the fruit flesh. The frequencies of vascular nodules in 61 'Gala' × 'Splendour' hybrids from New Zealand and British Columbia, Canada, were examined. These ranged from a mean of 0 to 12.1, depending on the hybrid. Thirteen hybrids were in the high frequency class (2.76-12.1), 28 in the low frequency (0.04-1.86), and 20 were without nodules. The mean nodule frequency in Sciros™ was 12.1 nodules per fruit, the highest of all hybrids examined. Our survey of 44 other cultivars confirmed the occurrence of vascular nodules in 'Gala' and 'Splendour', with mean vascular nodule frequency of 1.9 and 0.5 nodules per fruit, respectively. Nodules were also found in 'Newtown Pippin' (frequency 0.8), and in a 'Newtown Pippin' × 'Granny Smith' hybrid (frequency 0.1).

Free access

Ficus benjamina L. and Dracaena marginata Lam. were grown in a modified Hoagland's nutrient solution containing either 0, 0.22 or 5.52 mg Fe3+/liter (HEEDTA or EDTA). F. benjamina grew well at all Fe levels and showed mild chlorosis only at 0 mg Fe/liter. For D. marginata, growth decreased and chlorosis increased as solution Fe level decreased. F. benjamina exhibited a high capacity for Fe3+ reduction, which increased as Fe level decreased, reaching a maximum below 0.06 mg·liter-1 D. marginata exhibited a low capacity for Fe3+ reduction, which was slightly enhanced at 0.1 to 0.15 mg·liter-1. In both species, reduction occurred in the presence of roots, with minimal reduction in their absence. This result indicates that Fe3+ is reduced at the root surface and not by reductants released into the solution. F. benjamina increasingly lowered pH as solution Fe decreased, and always lowered pH more than D. marginata at all Fe levels. Total and extractable Fe concentration of leaves did not correlate well with chlorosis, whereas total Fe content per plant correlated highly with chlorosis. Chemical names used: N-hydroxyethyl-ethylenediamine-triacetic acid (HEEDTA), ethylenediamine tetraacetic acid (EDTA).

Free access