Rufus Chaney - Academia.edu (original) (raw)

Papers by Rufus Chaney

It has been difficult to impose different degrees of Zn deficiency on Poaceae species in nutrient... more It has been difficult to impose different degrees of Zn deficiency on Poaceae species in nutrient solution because most chelators which would control Zn to low activities also bind Fe 3+ so strongly that Poaceae species cannot obtain adequate Fe. Recently, a method has been developed to provide buffered Fe 2+ at levels adequate for rice using Ferrozine (FZ), and use of other chelators to buffer the other micronutrient cations. The use of Fe 2+ buffered with FZ in nutrient solutions in which Zn is buffered with HEDTA or DTPA was evaluated for study of Zn deficiency in rice compared to a conventional nutrient solution technique. The results showed that growth of rice plants in FZ + HEDTA-buffered nutrient solution was similar to that in the conventional nutrient solution. Severe zinc deficiency symptoms were observed in 28-day-old rice seedlings cultured with HEDTA-buffered nutrient solution at Zn 2+ activities < 10 -1°"6 M. With increasing free Zn 2+ activities, concentrations of Zn, Fe, Cu, and Mn in shoots and roots were quite similar for the FZ + HEDTA-buffered nutrient solution and the conventional nutrient solution techniques. The percentages of water soluble Zn, Fe, Cu and Mn in shoots with HEDTA-buffered nutrient solution were also similar to those with the conventional solution. However, with DTPA-buffered nutrient solution, the rice seedlings suffered severe Fe deficiency; adding more FeFZ3 corrected the Fe-chlorosis but shifted microelement buffering. Further, much higher total Zn concentrations are required to provide adequate Zn 2+ in DTPA-buffered solutions, and the contents of Mn and Cu in shoots and roots cultured with DTPA-buffered solutions were much higher than those with the conventional or HEDTA-buffered solutions. In conclusion, DTPA-buffered nutrient solutions are not suitable but the FZ/HEDTA-buffered nutrient solution technique can be used to evaluate genotypic differences in zinc efficiency in rice.

Two Coastal Plain soils were used to evaluate the effects of organic matter and Fe and Mn hydrous... more Two Coastal Plain soils were used to evaluate the effects of organic matter and Fe and Mn hydrous oxides on Zn phytotoxicity, and on Zn, Cd, and Mn uptake by soybean seedlings. Fertilized Pocomoke si and Sassafras si were limed to pH 5.5 and 6.3 with CaCO 3 when adding Zn (six levels between 1.3 and 196 mg/kg at pH 5.5; seven levels between 1.3 and 524 mg/kg at pH 6.3). Cadmium was added at 1% of the added Zn. 'Beeson' soybean (Glycine max L. Merr.) was grown 4 weeks, and the trifoliolate leaves evaluated for dry weight yield and for their Zn, Cd, and Mn concentrations.

Six bicarbonate and 2 Fe levels were used in nutrient solution to determine the optimum treatment... more Six bicarbonate and 2 Fe levels were used in nutrient solution to determine the optimum treatment combination for detecting small differences in Fe chlorosis resistance among soybean cultivars. The cultivars tested represented chlorosis resistant (Lakota, Hawkeye, Chippewa‐64, and Hodgson) and chlorosis susceptible (Williams, Hark, Anoka, and Wayne) classes, based on reported field scores. Treatments consisted of a factorial arrangement of 0, 5, 10, 15, 20, or 25 mM NaHCO3 and 4 or 6 μM FeEDDHA, with a 1:2 Fe:chelator ratio. All plants were grown in a modified 1/5 Johnson solution containing excess CaCO3 and 400 μM P, with NO3 N. Five mM increments of HCO3 increased the chlorosis severity in all cultivars at both Fe concentrations. Orthogonal polynomial analysis indicated that the rate of chlorosis increase was greatest at HCO3 levels less than 10 mM. Chlorosis was more severe at 4 than 6 μM Fe. At low Fe and high HCO3 , even resistant cultivars became chlorotic. For germplasm screening, the 6 μM Fe, 15 mM HCO3 treatment provided the best chlorosis class separation and closest relationship to average field observations.

(Phaseolus vulgaris L.). Copper was supplied through sewage sludge mixtures of varied Cu concentr... more (Phaseolus vulgaris L.). Copper was supplied through sewage sludge mixtures of varied Cu concentrations and through Cu-salt additions to the soil. Treatments were a factorial combination of four levels of Cu additions and four levels of total sludge additions. Soil and sludge pH values were limited to pH 5.0 to 5.5. Plant yield differences were minor. Data are reported showing the relationships of root, shoot, and total plant Cu contents with Cu 2+ activity, with DTPA-extractable Cu, with soluble Cu, and with sludge Cu concentration. The Cu source (sludge vs. salt) produced distinctly different curves in most every case. Sludge treatments demonstrated nonlinear relationships of Cu activity vs. Cu accumulation; these were fit with exponential functions. Higher shoot Cu concentrations occurred with the Cu salt treatments. Higher root Cu levels occurred at lower Cu 2+ activity values with sludge as the Cu source. This probably reflects the superior ability of the sludge to replenish or maintain the Cu supply in soil solution. Total soluble Cu was not related to plant Cu. The proportion of Cu in the sludge was closely linked with shoot Cu (r 2 = 0.94); root Cu levels also reflected the proportion of Cu in the sludge, but higher sludge rates resulted in increased root Cu. Increased labile, soluble, Cu-organic complexes with increased sludge rates would explain both the observed differences between salt and sludge treatments and the positive correlation of root Cu and sludge rate. Physiological control of Cu translocation within the plant is implicit in this reasoning. Continual monitoring of soil solution ion activity or a buffering index is needed to improve predictions of plant ion uptake. Additional Index Words: Donnan dialysis, ion-selective electrode, plant ion uptake, sewage sludge, trace metals. Minnich, M.M., M.B. McBride, and R.L. Chaney.

manure, respectively. The by-products also reduced the 0.5 M NH4F- extractable phosphorus (FEP) f... more manure, respectively. The by-products also reduced the 0.5 M NH4F- extractable phosphorus (FEP) fraction. Shifts in P forms between Miller, 1994). The Al 3 reacted with ammonia released FEP and 0.1 M NaOH-extractable phosphorus (SHEP) depended during the decomposition of uric acid and organic N upon the Al and Fe contents of the by-products while the combined in poultry manure. Amorphous aluminum hydroxides FEP SHEP pool remained constant. Phosphate sorption measure- formed in alum-treated manure bind and immobilize ments supported the observations that the Fe-rich by-product was soluble manure P. Spent residuals from water treatment more effective at reducing manure DRP and enhancing the formation plants also sorb and precipitate soluble manure P of SHEP forms at the expense of FEP than the Al-WTR. Composting (Peters and Basta, 1996). Unlike alum or aluminum had no effect on the efficacy of either by-product to reduce DRP. chloride used in the treatment of wastewater, the Al Potential mechanisms of enhanced P stabilization in treated manure in Al-WTR occurs as amorphous insoluble aluminum upon composting included chemical shifts from the DRP and FEP oxides and is less likely to form acidity when amended fractions to the citrate-bicarbonate-dithionite extractable P fraction. Thus, the choice of P immobilization agents affected the stability to manure or manure-amended soils. An iron-rich by- of immobilized P forms and should be taken into consideration in product of the titanium oxide extraction process from developing manure processing and nutrient stabilization methods. Dupont Chemicals (Wilmington, DE) has been evalu- ated as a component of a synthetic soil for the nursery industry (Goyette, 1992). The by-product contained sig-

The potential for excessive crop uptake of heavy metals from land previously amended with sludge ... more The potential for excessive crop uptake of heavy metals from land previously amended with sludge is of concern because of the persistence of heavy metals. Field studies were therefore conducted at two locations in 1983 and 1984 to examine the residual effects of sewage sludge on heavy metal uptake by soybean [Glycine max (L.) Merr.]. The Fairiand plots (Typic Hapludults) had been amended with two rates of anaerobically degested sludge in 1975. The Beltsville plots (Typic Paleudults) had been established in 1976 with limed-anaerobically digested, limed-raw, limed-compost, or heat-treated sludge and in 1978 with Nu-Earth (Chicago, IL) anaerobically digested sludge. Treatments consisted of various sludge rates and pH regimes. The concentrations of metals in soybean shoots at the R4 growth stage varied according to sludge type, application rate, and soil pH. Metal uptake from low metal, limed sludges was similar to that of controls. Metal uptake was, however, increased by unlimed sludges that were high in metal content. Digested sludge linearly increased shoot metal concentrations of Zn, Cd, Cu, and Ni. Compared to the unamended control, soybean Zn increased from 24 to 165 mg kg -I and CA increased from 0.06 to 0.25 mg kg -I at the 112 Mg ha -1 rate. The shoot Cd concenlration was over seven times higher from Cd rich Nu-Earth sludge as compared to the other sludges. Shoot Zn and Cd concentrations exhibited significant linear and quadratic relationships with rates of heat-treated and Nu-Earth sludge. There was a greater response of shoot Zn and Cd accumulation to sludge rate at low soil pH. At the 100 Mg ha-' rate of Nu-Earth sludge, soybean Zn and Cd concentrations, respectively, were 59 and 1.75 mg kg -1 at soil pH 6.4 and 84 and 2.54 mg kg-' at soil pH 5.8. These results indicate that sludge composition and soil pH can have a substantial influence on soybean metal uptake for at least 9 yr after the initial sludge application.

... 4. Page, AL, JJ Logan and JA Ryan. 1987. Land Application of Sludge. Lewis Publishers, Inc.Ch... more ... 4. Page, AL, JJ Logan and JA Ryan. 1987. Land Application of Sludge. Lewis Publishers, Inc.Chelsea, MI. 5. Mulchi, CL, PFBell, C. Adamu and JR Heckman. 1987. Bioavailability of heavy metals in sludge-amended soils ten years after treatment, pp. 235-259. ...