Search

The biological and therapeutic significance of polyketides is a powerful impetus for the development of efficient methods to facilitate their construction. Emulating the efficiency of polyketide biosynthesis, a sophisticated arsenal of aldol-based strategies has evolved that is contingent on the generation of single enolate isomers. Since this has the potential to compromise efficiency in reagent-based paradigms, direct catalysis-based solutions would be enabling. To complement the array of substrate-based strategies, and regulate enolate geometry at the catalyst level, a direct catalytic alkylation of esters with oxyallenes has been developed. Synergizing metal hydride reactivity with Lewis base catalysis has resulted in a broad reaction scope with useful levels of stereocontrol (up to >99% ee). Facile derivatization of these ambiphilic linchpins is demonstrated, providing access to high-value vicinal stereocenter-containing motifs, including 1,2-amino alcohols.

Rhizobium radiobacter (also known as Agrobacterium tumefaciens), has been reported to be found on more than 600 different plant species worldwide including many common vegetables, weeds, deciduous and evergreen trees and shrubs. This document discusses the biology, symptom expression, and management of this bacterium.

To the authors' knowledge, this is the first report of Boxwood blight in Florida. Accepted for publication 22 September 2016.

Lagerstroemia is a genus of plants comprised of deciduous shrubs or small trees native to China southward into Southeast Asia. L. indica, the oldest and most widespread species in cultivation in the United States, has been cultivated as an ornamental for centuries and was introduced to the Southeastern U.S. over 175 years ago. Much has been disseminated on the culture and commercial production of crapemyrtle species and cultivars; including plant forms and function, adaptability to macro and micro environment, growth and floral characteristics, and commercial production and landscape culture and maintenance. Since the introduction of L. indica in the United States, L. fauriei, L. subcostata and L. limii have also been introduced. However, since the mid 1970s, interspecific hybrids between L. indica × L. fauriei comprise the majority of new cultivar introductions. Breeding efforts have resulted in 133 commercially available cultivars as of December 2011 that include cultivars with ever improving form and flowering, new flower colors, ornamental bark, ornamental foliage, and disease tolerance. However, there is a wide range among cultivars of tolerance to key pests and diseases such as powdery mildew, Cercospora leaf spot, flea beetle and Japanese beetle. A large number of pests and plant pathogens also negatively affect crapemyrtle health including granulate ambrosia beetle, crapemyrtle aphid, bark scale, bacterial leaf spot, sooty mold and soil-borne root and crown diseases. This review focuses on crapemyrtle culture, in both commercial and landscape settings, with an emphasis on optimizing plant health through the discussion of major abiotic and biotic stressors and cultivar variation in tolerance to these stressors.

Lagerstroemia ´ 'Natchez' trees were topped, pollarded, or not pruned for 4 consecutive years. The first time trees were pruned in 1998, pollarding required more time than topping. However, the time required to top trees increased in each subsequent year; pollarding time remained the same for each year. Longitudinal sections through stems showed that barrier zones and decay extended farther behind heading cuts on topped trees 5 years after the initial pruning than with the cuts on pollarded trees. Trees in the topping treatment formed a visible, dark-colored barrier zone along the cambium present at the time of wounding, averaging 74 cm (2.5 ft) in length, originating from the heading cuts made through 4- to 5-year-old wood. Barrier zone length on pollarded trees was only 1.8 cm (0.7 in) behind the original heading cuts through 2- to 3-year-old wood. Topping trees resulted in a sixfold increase in the volume of wood contained in dead stubs in the canopy compared to pollarding trees. Topping increased the need for cleaning the canopy of dead branches. A collar formed at the base of sprouts that were less than 0.64 the diameter of the largest sprout 5 years after the original heading cuts on trees in the topped treatment.

ENH-1094, a 16-page illustrated factsheet by Edwin R. Duke and Gary W. Knox, provides assistance in selecting cold hardy palms for northern Florida, including sections on growing conditions, maintenance, treating cold damage, and availability. Includes references and a 10-page table showing characteristics of palm varieties suitable for northern Florida. Published by UF Department of Environmental Horticulture, February 2008. ENH1094/EP359: Palms for North Florida (ufl.edu)