Lupinus havardii Wats. (Big Bend bluebonnet) has received considerable attention as a new specialty cut flower crop. We studied the consequences of Ca fertigation on growth, water use, and mineral nutrient uptake of L. havardii (`Texas Sapphire') for 88 days in a greenhouse. Four Ca concentrations were included (as CaCl2) in the fertigation solution at concentrations of 0, 2.5, 5.0, or 10.0 mm. Calcium supply did not affect the number of racemes produced per plant or total dry matter accumulation per plant. However, root dry matter accumulation, root: shoot ratio, net root mineral nutrient accumulation (milligrams P, K, Ca, Mg, and Fe per plant; micrograms Mn, B, and Cu per plant), and the preferential allocation of mineral nutrients to roots were influenced quadratically by CaCl2 supply, increasing up to 5.0 mm CaCl2 and then decreasing at 10.0 mm CaCl2. Lack of root sink response by plants exposed to 10.0 mm CaCl2 was associated with lowest daily rate of pot evapotranspiration, probably resulting from osmotic or Cl toxicity stress. Increased root sink strength for dry matter and mineral nutrients in response to CaCl2 supply up to 5.0 mm Ca is consistent with calcicole-like behavior and the native distribution of L. havardii on xeric, calcareous soils, where root growth and expansion favoring water and mineral nutrient acquisition may be of significant adaptive value for survival. The Carelated increase in root growth was reflected in up to a 5% to 20% increase in fertilizer P and K recovery per plant. Results indicate that Ca fertilization may be an effective horticultural strategy in greenhouse production of L. havardii, particularly for matching the natural edaphic habitat of the species and thus increasing efficiency of water and mineral nutrient management.

Lupinus havardii Wats. is a promising new specialty cut flower crop, but data on its greenhouse culture and management are limited. Two experiments investigated senescence-delaying activity of preharvest Ca fertilization and postharvest preconditioning with 1-MCP on L. havardii `Texas Sapphire' cut flower stems (racemes). In the first study, Ca (as CaCl2) was added to the nutrient culture solution at concentrations of 0, 2.5, 5.0, and 10.0 mm for 88 days in a greenhouse. Additional CaCl2 supply did not affect the total number of racemes produced per plant, the average number of flowers per raceme, or the retention of individual flowers on cut racemes over a 7-day vase period. However, Ca concentration in cut raceme tissues, ranging from 5.3 to 7.6 mg·g-1 dry weight, increased linearly with increasing Ca concentration in the nutrient solution, which was accompanied by a linear increase in average fresh weight retention per raceme and individual mature flowers (up to 7% above controls) during the 7-day vase period. In the second study under similar plant culture and vase conditions, 1-MCP applied at harvest resulted in an average fresh weight retention increase of 9% above controls during 7 days in the vase. Equivalent levels of desiccation in control racemes (loss in fresh weight retention) were delayed by 1.5 to 3 days in racemes with the highest Ca concentrations and those that had been preconditioned with 1-MCP. In view of the physiological significance of desiccation in cut flower quality loss, preharvest Ca fertilization and postharvest 1-MCP preconditioning may be useful techniques for delaying senescence and maintaining vase quality of cut L. havardii racemes. Chemical name used: 1-methylcyclopropene (1-MCP)

During October 2005, rust lesions were observed on leaves of gladiolus (Gladiolus sp.) plants being grown for flower production in a 20-ha field in eastern Michoacán, México. Disease incidence was near 100% in the field. Five symptomatic plants were collected on 11 and 25 October 2005, from each of 10 farms for further examination. Uredinia were scattered, orange, elliptical to irregular, and arranged transversely across the leaf. The sori were covered by the epidermis initially and later were erumpent and pulverulent. Urediniospores were bright yellow gold, ovate to oblong, and measured 15 × 19 μm (average). The urediniospore wall was hyaline and minutely echinulate. Telia were scattered, dark brown, elliptical, arranged transversely across the leaf, and were covered by the epidermis. Teliospores were irregularly pyriform, ovate, irregular or angular, light to dark brown with a conical or truncate apex and measured 17 × 23 μm (average). The teliospore wall measured 1 μm (average) thick at the sides and 3 μm (average) thick at the apex. Pedicels were light yellow and measured as much as 60 × 3 μm (average). On the basis of these characters, the rust was identified as Uromyces transversalis (Thüm.) G. Winter (1). To our knowledge this is the first report of U. transversalis causing gladiolus rust in Michoacán, México. Originally reported from Africa, the disease has been reported from Argentina, Brazil, southern Europe, and Oceania (1). Gladiolus rust caused by Uromyces transversalis is a quarantine disease for Europe and the United States. There have been unpublished reports of interceptions of this rust on cut flowers of gladiolus going from México into the United States (1). References: (1) J. R. Hernández. Invasive Fungi. Gladiolus Rust. Systematic Botany and Mycology Laboratory, Online publication. ARS, USDA, 2004.

Verticillium wilt caused by the fungus Verticillium dahliae is found world-wide and attacks a wide range of plants. In the summer of 2001, a wilt disease of Amygdalus communis (sweet almond) cultivated in the Xinjiang municipality in China was first observed. The characteristic symptoms of typical wilt included wilt of leaves and twigs, and brownish discoloration of vascular tissues. Ultimately, the branches and entire trees wilted and died. To identify the causal agent, both traditional and PCRbased methods were attempted.In 2004 and 2005, a Verticillium sp. was isolated from the xylem of diseased branches on potato dextrose agar (PDA). The fungus produced dark colonies on PDA, produced rotiform conidiophores with 2 -4 layers, one-celled colourless olivary conidia, and small black microsclerotia. It was identified as V. dahliae based on morphological characteristics according to the description of Smith (1965). Ribosomal DNA (regions ITS1, 5·8S rDNA and ITS2) was amplified and sequenced (GenBank Accession No. EU109532). Sequence analysis revealed that the fungus isolated from A. communis is identical to a Greek strain of V. dahlia (GenBank Accession No.AF104926).Each of six seedlings of A. communis , approx. about 20 cm high in sterile soil, was inoculated by injecting 20 μ L single-conidial suspension containing 1 × 10 6 conidia mL -1 into the base of the stem. The inoculated seedlings were incubated at 25 ° C. Water-soaked lesions appeared on the leaves of all of the inoculated seedlings after 4 days and then dark brown lesions appeared around the injected sites and spread rapidly upwards. The inoculated seedlings wilted and died after 7 days. The pathogen was reisolated from the inoculated stems. Control seedlings, inoculated with an equal volume of sterile water, remained healthy.The fungus was previously recorded in Xinjiang municipality and other provinces in China infecting many Rosaceae and Malvaceae plants (Tai, 1979), but this is the first report of V. dahliae associated with wilt of A. communis in China. ReferencesSmith HC, 1965. The morphology of Verticillium albo-atrum , V. dahliae , and V. tricorpus .

Correlative control of long-distance transport processes consists of an attraction or mobilizing power of a sink organ coupled to internal degradative reactions in a target source organ and the reallocation of its resources. This phenomenon is widely recognized in the agronomic whole plant literature but poorly recognized in the floriculture literature. We calculated supply and demand balances for water, total dry matter (TDM), and minerals during a 6-day postharvest evaluation of the spatially diverse, detached, indeterminate inflorescence of Lupinus havardii Wats. ‘Texas Sapphire’ held in deionized water. The apex approximately doubled its original (harvest day) amounts of total N, P, K, Mg, and S and increased its TDM and water content by 55% and 85%, respectively, all at the expense of lower-most mature flowers. Net export from the lower mature flower fraction and, when applicable, upper mature flowers, accounted for the following apical gains: 46% of TDM, 102% of water, 100% of N, 94% of P, 99% of K, and 54% of Mg and S. Directed reallocation of resources from the senescing lower mature flowers (the main “target”) to the apical sink (the “mobilizing center”) bore a marked resemblance to the coupling of remote sink demand with vegetative decline reported in monocarpic plants (i.e., vegetative-to-reproductive exchanges), but with two distinguishing characteristics: 1) the TDM and mineral exchanges were strongly restricted to flowering units, and 2) the contributions of water, N, P, and K exports to apical sink demand were at or near 100%. This article is the first that we are aware to provide an internal supply and demand balance sheet reflecting, quantitatively, the postharvest reallocation of internal resources from mature reproductive tissues to generative reproductive tissues of a cut inflorescence.