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Objective: To study the prevalence of vitamin [B.sub.6] deficiency in common variable immunodeficiency and the impact of vitamin [B.sub.6] supplementation on immune function in the disorder. Design: Open, non-blinded. Setting: [...]

A primary economic concern of sod producers is loss of sod quality during the transportation and storage phases of a sale. Previous research and field experience indicate that soil and plant respiration rates, and thus the rate of pallet heating, may be reduced by harvesting in the morning, lowering mowing heights and removing clippings, and minimizing tissue nitrogen and soil moisture before harvest. However, even when proper cultural guidelines are followed, excessive sod heating and tissue damage often occurs. Various pre- and post-harvest chemical treatments aimed at protecting leaf tissue integrity during and after supraoptimal heating have shown promise for increasing transplant success. One of these compounds is the natural plant growth regulator salicylic acid (SA). This study was conducted to investigate the influence of pre-harvest fidiar application of SA on transplant injury and root strength of tall rescue (TF; Festuca arundinacea Schreb.) and Kentucky bluegrass (KBG: Poa pratensis L.) sod following supraoptimal heating. Salicylic acid was applied at 0.5 kg [ha.sup.-1] to the turfgrass 10 d before harvest and canopy photochemical efficiency was measured 1 d before harvest. Harvested and roiled sod was subjected to high temperature stress (38-40°C for 72 or 96 h), transplanted into the field, and injury and root strength were determined. Application of SA enhanced the pre-harvest canopy photochemical efficiency of KBG and TF sod in both years. Averaged over years and heat duration, SA increased canopy photochemical efficiency by 12% for KBG and 14% for TF. Salicylic acid reduced visual injury and enhanced post-harvest root strength in both years. Averaged over years and heat duration, SA increased transplant root strength by 26% for KBG and 9% for TF. These data suggest that pre-harvest foliar SA application may improve shelf life and transplant success of supraoptimally heated cool-season sod., KENTUCKY BLUEGRASS AND TALL FESCUE are widely used cool-season turfgrass species for sod production in many parts of the world. Market forces often require cool-season sod to be harvested, transported, [...]

A primary economic concern of sod producers is loss of sod quality during the transportation, storage, and transplant stages of sale. Although a number of cultural methods have been documented for potentially reducing sod heating, many of the biological mechanisms are yet to be investigated. This study investigated the influences of selected plant growth regulators (PGRs) on sod tolerance to stress during storage by examining the relationship between preharvest photochemical efficiency (PE) and transplant rooting of Kentucky bluegrass (Poa pratensis L., KBG) sod. The PGRs, including propiconazole (propiconazole [1-(2-(2,4-dichloropheny)-4-propyl-1,3-dioxolan-2yl)methyl-1-H-1, 2,4-triazole]; PPC), and seaweed (Ascophyllum nodosum Jol.) extract (SWE) plus humic acid (93% a.i.; HA), were applied alone, or in combination, to the KBG 2 wk before harvest in 1999 and 2000. Photochemical efficiency was measured immediately before harvest. The harvested sod was subjected to high temperature stress (37°C) for 72 or 96 h. The heated sod was replanted in the field and transplant visual turf injury and rooting were determined. Foliar application of SWE at 0.5 kg [ha.sup.-1] plus HA at 1.50 kg [ha.sup.-1], PPC at 0.44 kg [ha.sup.-1] alone, or a combination of SWE + HA with 0.22 kg [ha.sup.-1] PPC, enhanced PE of preharvest sod in both years. Extension of heat duration from 72 to 96 h caused significantly more injury to the sod in 1999. All PGR treatment combinations reduced visual turf injury. On average in 1999 and 2000, SWE + HA, PPC, and SWE + HA + PPC enhanced transplant rooting by 21.8, 34.7, and 44.2%, respectively. Regression analysis indicated that KBG with higher preharvest PE suffered less turf injury and produced greater rooting after transplantation. The data suggest that foliar application of SWE + HA, PPC alone, or in a combination, may improve shelf life and transplant rooting of KBG sod., KENTUCKY BLUEGRASS is a widely used cool-season turfgrass species for sod production in the USA and many other regions of the world. High quality sod is the goal of sod [...]

In many areas, nonpotable water is relegated for turfgrass irrigation. This research is conducted to determine if exogenous applications of selected substances to turfgrass could reduce the effects of saline irrigation. Field and greenhouse experiments investigated the effect of seaweed extracts, triazole fungicides, and Fe on Kentucky bluegrass (Poa pratensis L. cv. Plush) grown under various levels of salinity. In Exp. 1, Kentucky bluegrass was treated with a proprietory seaweed extract (SE) at 38 L ha to the -1, propiconazole ( (PPC) at 1.8 L active ingredient (a.i.) ha to the -1, and chelated Fe (Na-diethylene-triamine-pentaacetate-chelated Fe) at 4.7 kg a.i. ha to the -1. In Exp. 2, treatments included SE at 56 L ha to the -1, and chelated Fe at 2.2 kg a.i. ha to the -1. Two weeks after treatment in both experiments, plugs taken from field plots were transplanted into 4-L metal containers. The transplanted plugs were watered with 0, 0.15, or 0.3 S m to the -1 NaCl solutions for 7 wk. As salinity increased, leaf water stress increased, and clipping dry weight and rooting decreased. All treatments, except Fe, enhanced growth under 0.15 S m to the -1 salinity water. Under the higher salinity, PPC enhanced foliage weight, and all treatments, except Fe, stimulated rooting. Propiconazole-treated plants had the strongest root system under the higher salinity. In Exp. 2, CPC was the most active chemical in enhancing rooting. Result indicate that selected materials have potential use for Kentucky bluegrass production in saline environments.

The utility of the surface of Thebe, a small inner moon of Jupiter, as a probe for the remote sensing of its orbit's environment was examined. Observations were conducted using a Texas Instrument 800 X 800 computerized crystal display camera with a reimaging chronograph. The synchronous rotation of Thebe and the linkage of this inner satellite system with the Galilean system was established.