Search Results

Abstract

Pollen morphology of 10 Vaccinium species, 10 interspecific hybrids, and 3 colchicine-induced polyploids were studied using scanning electron microscopy. Size, exine patterning, furrow and pore size and shape, and general appearance were investigated. Although differing morphological features were generally lacking, some interspecific differences and variation within hybrid populations were noted. Furrow and pore sizes, and the associating opericuli were the most valuable characters. Some species had large furrows with large rounded pores and others had small furrows with insignificant pores. Exine patterning was minimal and, when present, generally occurred in the inter-colporate regions. F₁ populations of V. corymbosum × V. elliottii had the greatest exine variation and the degree of exine patterning revealed a possible dosage effect. Exine patterns suggest that the ancestors of V. myrsinites may be V. darrowi and V. elliottii rather than V. darrowi and V. tenellum as previously proposed by Camp.

Abstract

Detached shoots of double-flowered peach [Prunus persica (L.) Batsch] selections Fla. 6-1 and Fla. 0-5 were successfully opened in floral solutions containing 1 to 10% sucrose in deionized water. Addition of 8-hydroxyquinoline citrate (8-HQC), gibberellic acid (GA₃), or 6-benzylaminopurine (BA) to solutions did not extend vase life. Solution uptake rate decreased over the 8-day life of the shoots and was influenced by solution molarity. Xylem plugging by pectic-type materials increased with time in solution. Addition of 1% ethanol to the floral solution hastened time of first opening, decreased the extent of xylem plugging, and extended vase life. Ethanol at 2% extended vase life and increased solution uptake rate over solutions containing sucrose alone.

Abstract

Hydraulic conductivity decreased logarithmically over an 8-day period in detached flowering peach stems [Prunus persica (L.) Batsch]. Decreased hydraulic conductivity was negatively correlated (r = - 0.96) with an increase in the number of plugged vessels and positively correlated with a decrease in the percentage of functional vessels (r = 0.97). Ethylene production from flowering shoots peaked after 7 days in the holding solution but decreased rapidly thereafter. Addition of 1% ethanol to the holding solution increased xylem hydraulic conductivity and delayed the surge in ethylene production.

In January, 1990, a team of U.S. and Chilean scientists collected native and cultivated Fragaria from central and southern Chile. During the course of this expedition, 363 new accessions of Fragaria were collected. Approximately 2,500 plants of 250 clones were collected from 66 sites in 19 different areas, and 113 seedlots (estimated at over 100,000 seeds) were obtained.

Plants were collected from a wide range of habitats, and considerable variability was observed in vegetative and reproductive characteristics. Fruit were round to conical in shape, deep red to white in color, soft to moderately firm, with soluble solids ranging from 5-18%, dull to glossy skin, bland to strong flavor, low to very high aromatics, and difficult to moderately easy capping. Fruit size in situ approached 4 g, while fruit larger than 12 g were found under cultivated conditions. Strawberry aphids (Chaetosiphon fragaefolii) were found on plants in situ and under cultivation. Little or no evidence of other pests were observed on clones collected in situ.