College of Agricultural Sciences

The specific objectives of the study were to determine whether susceptibility of field-grown pear trees to P. syringae is related to N concentration in stems and is altered by spraying trees with urea or the defoliant CuEDTA at different times in the autumn before and after inoculation with the pathogen.

The intent of this study was to determine the (1) effect of soil versus foliar nitrogen (N) applications during the summer on tree growth, and (2) effect of soil versus foliar N applications during summer on N uptake in the autumn in young apple trees.

The purpose of this study was to determine which source of nitrogen (N) (i.e. reserves or spring fertilizer applications) has the greater effect on new growth of almond nursery trees. 'Nonpareil' almond (Prunus dulcis (Mill) D. A. Webb) trees on 'Nemaguard' rootstocks were used in the study.

Research was conducted with the intent of evaluating the effect of different levels of root damage at planting on nitrogen uptake and growth of bench-grafted young apple (Malus domestica Borkh 'Fuji'/M.26) nursery trees.

This study focuses on early season changes in nitrogen (N) uptake and amino acid distribution at different root zone temperatures to test whether (1) temperature effects on N uptake are influenced by plant growth stage, and (2) changes in amino acid distribution are related to N uptake.

A study was conducted on almond trees to (1) determine whether soil N application alters N remobilization; (2) quantify the effects of soil N availability in the spring on N uptake, distribution, and new growth; and (3) determine the most efficient time for spring soil N applications.

A study was conducted to determine the physiology of graft formations in Picea pungens 'Hoopsi' scions grafted on Picea abies rootstocks. The purpose of the study was to identify factors limiting grafting success and improve production techniques.

A technical report on what is know and what is not known about Pseudomonas syringae in the nursery industry. Main topics are plant symptoms, severity of the disease, classification of Pseudomonas syringae isolates, sources and survival, hosts, and controls and recommendations.

A guide for the production of lilacs for the duel purposes of cut-flower production and landscape plantings. The history of the lilac as a forced, cut flower is summarized along with descriptions of species and cultivars, growth and development, forcing and flowering, and propagation methods.

An investigation was conducted into the increased susceptibility of pear nursery trees to infection by Phytophthora syringae following fall foliar sprays of urea which increased nitrogen (N) content in the trees. The authors discuss the methods and materials involved in the experiments along with the results.