R. T. Mueller

Barium toxicity in plants

Abstract The purpose of this study was to determine the level of Ba in plants necessary to cause yield depressions. Barium levels of about 2% in bush bean leaves and 1% in barley leaves decreased yields considerably. The levels were obtained after application of 2000 μg Ba per g of soil as Ba(NO3)2 with equivalent nitrate added in controls.

Arsenic phytotoxicity and interactions in bush bean plants grown in solution culture

Abstract Bush bean plants (Phaseolus vulgaris L. cv. Improved Tendergreen) were grown in solution culture with varied levels of As to ascertain levels and plant concentrations associated with phytotoxicity and to determine if there were any interactions between As and other minerals in plants. The level of 10‐4 M arsenate in solution resulted in considerable plant damage. Plant concentrations of As at this application rate were 3. 6, 18. 8 and 41. 7 μg/g respectively for leaves, stems, and roots. This level of arsenate resulted in increased Fe, Cu, Mg, Al, Si, Ti and Ba in all plant parts except Mg in roots. All of the increases may be due to concentration. Simultaneously there was depressed Mn, P and Ca in all plant parts. K also was depressed in roots. These depressions were not due to dilution.

High levels of four heavy metals on the iron status of plants

Abstract Bush beans (Phaseolus vulgaris L. cultivar Improved Teadergreen) were grown for three weeks in a simulated calcareous soil (Yolo loam + 2% CaCO3) with Co, Ni, Zn, and Cu applied as sulfates at the rate of 1000 ppm metal on the dry soil basis. Iron at 5 ppm as FeEDDHA (ethylenediamine di(o‐hydroxyphenylacetic acid)) was applied to half the plants to test its ability to overcome any of the apparent Fe deficiency induced by heavy metals. Cobalt and Ni were the most toxic of the four metals; Cu was next with only mild effects due to Zn. Copper decreased Fe concentration in shoots while Ni increased it. Nickel decreased Mn in shoots; Zn and Co increased Mn in shoots. The FeEDDHA overcame none of these toxic effects of heavy metals even though the symptoms were similar to those of Fe deficiency. Nickel decreased the total quantity of cations in leaves.

Excess EDDHA in the nutrient solution on iron uptake by bush bean plants

Abstract Excess EDDHA (ethylenediamine di(o‐hydroxyphenylacetic acid) ) had little effect on leaf concentrations of Fe in bush beans (Phaseolus vulgaris L. var Improved Tendergreen) when grown in nutrient solution at three pH values from 4.3 to 8.7. An excess of EDDHA 20 times that of Fe decreased yields slightly, but not as result of Fe deficiency. A resulting hypothesis is that chelated Fe can be transferred from chelating agent to uptake sites on roots without going in the ionic form through the solution around roots.

Calcium-trace metal interactions in soybean plants.

Abstract Hawkeye soybeans (Glyclne max L.) were grown for 13 days in nutrient solutions in a glasshouse with differential Ca and trace metal concentrations. Yields were little affected by low Ca levels without excesses of trace metals but yield depressions for excesses of Ni, Cd, Al, Ma, and Cu generally were greater at low Ca levels than at a high level. Ca, Mg and K levels in plants were all depressed by the trace metals. Some of the effects were expressed also in roots. The 10–3M level of Al resulted in virtually no Ca in roots and in diminished transport to shoots. The trace metal concentrations in leaves generally decreased with increasing Ca.

Use of waste pyrites from mine operations on highly calcareous soil

Abstract A waste pyrite material containing 45% S from a mine operation in Colorado when applied at a rate equivalent to 400 metric tons/ha to a highly calcareous soil overcame Fe deficiency in the Fe‐inefficient PI54619–5–1 soybeans (Glycine max L.). Zinc concentrations in leaves and stems were increased simultaneously. On a slightly acid soil the same level of pyrite considerably acidified the soil and resulted in toxicities. In another experiment in which the pyrite was mixed with small quantities of soil and applied in bands in the center of the pot, only 1/10 as much pyrite was necessary to overcome the Fe deficiency in the soybeans.

Influence of washing of soybean leaves on identification of ikon deficiency by leaf analysis

Abstract Iron inefficient PI54619–5–1 soybean (Glycine max L.) plants were grown for 17 days in calcareous Hacienda loam soil with and without added FeEDDHA and with half in a glasshouse where plants would be reasonably free of dust, while the remainder were outside where plants were exposed to a normal amount of dust. Primary and trifoliate leaves were separated, half of each leaf washed with rubbing in 1/10N HC1 while the others were not washed. Large amounts of Fe, Ti, Si and Al were washed from leaves grown outside but relatively little from those grown in the glasshouse largely because the latter were initially cleaner. Iron deficient trifoliate leaves from plants grown outside had higher concentrations of these four elements after washing than did similar leaves grown in a glasshouse. Since iron deficiency was very pronounced for both locations it can be concluded that the Fe derived from dust was nonfunctional and that the washing technique removed foliar Fe from leaves but not sufficiently well to...

Micronutrient supplying power of pyrite and fly ash

Abstract Bush bean plants (Phaseolus vulgaris L. cv Improved Tendergreen) were grown in nutrient solution with added waste mine tailings pyrite and also coal fly ash to test their ability to supply micronutrients to plants. The ability of fly ash to supply K was also tested. The pyrite was a satisfactory source of Fe, Mn, Zn, B and Cu to the solution cultures. The pyrite also supplied Ca. The fly ash supplied inadequate Fe and Mn but adequate quantities of Zn, B and Cu. It supplied adequate Ca and inadequate K. Both pyrite and fly ash supplied some Cd (when solution was acid), Cr and Pb to roots but not in detectable amounts to shoots. In another experiment, fly ash also failed to supply K to bush bean plants and failed to supply Zn. Iron, B, Si, Cu, Mo, Sr, Ba and some Ni and Cr were supplied to leaves; Si, Sr, Ba, Ni and Cr were supplied to roots by the fly ash. None of these elements seemed to result in phytotoxicity. A suggestion is made that fly ash and pyrite could be blended for soil application of...

Calcium uptake and distribution in plants.

Abstract Calcium uptake and distribution in plants are influenced by many factors. Root uptake seems to be independent of metabolic inhibitors but transfer to shoots is drastically reduced by such inhibitors. K uptake increases with root temperature which in turn results in depressed Ca uptake. Plant species differences in the proportion of K vs Ca uptake are often related to root cation exchange capacity. The cations K, Mg, Na, NH4+, and H+ directly and indirectly depress Ca uptake and distribution. Their effects are more pronounced at low Ca concentrations than at high. Lime‐induced chloros.is is associated with depressed Ca levels in leaves and tests under controlled conditions indicate that bicarbonate results in root retention of Ca and a decrease of Ca in leaves. Nitrate as a complementary ion promotes Ca uptake by plants. Trace metals in excess inhibit calcium uptake. Aluminum in particular greatly depresses Ca retention by roots as well as Ca uptake and transport to shoots. Leaves generally increa...

Selenate toxicity effects on bush beans grown in solution culture

Abstract Bush beans (Phaseolus vulgaris L. cv Improved Tendergreen) were grown in solution culture with 0, 10‐6, 10‐4, and 10‐3 M levels of Na2SeO3. Mild toxicity was obtained for 10‐4 M and severe toxicity at 10‐3. At severe toxicity, leaves were stunted and had brown spots. Selenium was fairly evenly distributed in plant parts. At severe toxicity, concentrations in μg/g were leaves 901, stems 1058, and roots 1842. The high level of Se also decreased P, Ca, Mg, Mn and K concentrations in leaves and P and Ca in roots. Silicon and Ti tended to be higher with the highest Se level.