Growth chamber, greenhouse, and field experiments were conducted with fungicides and biological control agents, including nonpathogenic isolates of Fusarium oxysporum, to test their ability to control disease caused by F. oxysporum f. sp. asparagi and F. proliferatum. In greenhouse studies with asparagus seedlings in soil, Trichoderma harzianum strain T-22, benomyl, and fludioxonil treatments increased root weight and decreased root disease compared with the infested control when a low level of F. oxysporum f. sp. asparagi and F. proliferatum was used. The fungicide fludioxonil limited plant death caused by Fusarium spp. at high inoculum levels, whereas T. harzianum strain T-22 was not effective. Nonpathogenic isolates of F. oxysporum were effective in limiting Fusarium disease on asparagus seedlings in culture tubes, although isolates differed in their ability to control disease caused by F. oxysporum f. sp. asparagi and F. proliferatum. In greenhouse studies, no significant differences in plant death were found between asparagus plants growing in media infested with F. oxysporum f. sp. asparagi and F. proliferatum and left untreated, and those treated with nonpathogenic F. oxysporum. The efficacy of fungicides and biological control products to control Fusarium crown and root rot under commercial field conditions could not be evaluated due to low disease pressure.

Experiments with applications of NaCl (560 and 1,120 kg/ha) and lime (6,719 kg/ha) were conducted in asparagus fields in commercial production (one healthy and one exhibiting symptoms of early decline), and an experiment with NaCl (1,120 kg/ha) was conducted in a badly declined research field at Michigan State University from 1998 to 2000 to determine whether these treatments control Fusarium crown and root rot of asparagus. Growth chamber and greenhouse studies were conducted to test the ability of alternative forms (CaCl2, NH4Cl, and MnCl2) of chloride salt to reduce disease caused by F. oxysporum f. sp. asparagi and F. proliferatum. NaCl applications increased yield and fern health in the research plot, but not in commercial fields. Soil tests in these fields indicated that NaCl did not decrease levels of calcium, magnesium, or potassium, and did not affect pH. In growth chamber studies with asparagus seedlings in Hoagland's agar test tubes, and in greenhouse studies with asparagus seedlings in soil, none of the alternative forms of chloride salt tested were more effective than NaCl in controlling Fusarium crown and root rot.

Animals fed sole diets of kale (Brassica oleracea) were compared with animals fed ryegrass-clover pasture grown on the same soil type in two experiments. In Expt 1 young cattle grazed the two forages for 24 weeks, with supplementary copper and iodine being administered by injection. In Expt 2 young sheep were individually fed the two forages indoors at equal D.M. intake.Animals grazing kale in Expt 1 showed the characteristic symptoms of haemolytio anaemia from ruminal fermentation of S-methyl cysteine sulphoxide (SMCO) (Smith, 1974). This was most severe over the first 6 weeks, during which live-weight gains were very low (250 g/day). In the absence of copper supplementation animals grazing kale showed symptoms of copper deficiency. This was characterized by live-weight gain remaining low throughout the experiment (mean 280 g/day), rapid depletion of liver copper reserves, progressive reductions in serum copper concentration, reductions in erythrocyte copper and reduced glutathione (GSH) concentrations and a massive hepatic accumulation of iron. Copper deficiency only slightly lowered heart muscle copper concentration in kale-fed cattle, and this was counteracted by heart hypertrophy. The major effects of copper deficiency in kale-fed cattle were in erythrocytes, and a metabolic diagram is presented showing these effects to be biochemically similar to those produced by ruminal fermentation of SMCO.Copper supplementation of animals grazing kale increased live-weight gain (mean 425 g/day), reduced Heinz body formation, allowed the animals to recover gradually from the haemolytic anaemia and prevented other symptoms of copper deficiency. In contrast, animals grazing ryegrass-clover pasture showed only a very mild depletion of copper, there being no response in live-weight gain to copper supplementation.Activity of the enzyme glutathione peroxidase (GSH-Px) in whole blood was dependent upon blood selenium concentration in cattle fed both diets. In cattle fed on kale, bub not on pasture, reductions in erythrocyte GSH due to ruminal fermentation.. of SMCO and to copper deficiency were also associated with depressed blood selenium status.Glucosinolates were present in the kale (11 /*M/g D.M.) but absent from the pasture diet. Despite this, neither T 4 production from the thyroid gland nor the conversion of T 4 to T 3 appeared to be impaired by kale feeding in either Expt 1 or Expt 2. In Expt 1 serum T s concentration was better related to live-weight gain than was serum T 4 concentration, in accord with T 3 being the active form of the thyroid hormone.It is concluded that supplementation with copper but not iodine is essential where growing cattle are fed sole diets of kale for periods in excess of 12 weeks.

The susceptibility of wool to yellowing was determined on samples from fleeces of 36 Merino wethers by a laboratory procedure involving incubation at 40�C for 5 days. The sheep, although originating from several different flocks, had been grazing together for 6 years. These susceptibilities were compared with the concentrations of suint and wax in the fleece, with fibre diameter, and with mineral concentrations in suint or yolk from the greasy wool. While the susceptibility of the fleeces was correlated with suint content (r = 0.852), the highest correlations were with the potassium concentrations in either suint before (r = 0.947) or yolk after (r = 0.938) incubation. There were significant differences in the concentration of potassium in the wool after washing, between the four most resistant and the four most susceptible fleeces, and in the effect of incubation on these potassium concentrations. No differences were detected in concentrations of other minerals in the clean wool nor in the relative proportions of amino acids.

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