P. M. Patel

Effect of chelating agents on phytotoxicity of lead and lead transport

Abstract The major purpose of these experiments was to determine if Pb uptake by plants was significantly increased by chelating agents used in plant nutrition. The interaction of Pb with some other elements in barley plants (Hordeum vulgare L. C.V. Atlas 57) and bush bean (Phaseolus vulgaris L. C.V. Improved Tendergreen) was studied in a glasshouse with different rates of Pb in solution culture and in amended (control, S, CaCO3, MgCO3) Yolo loam soil with and without the chelating agent DTPA (diethylene triamine pentaacetic acid). In a solution culture experiment, 10‐3 M Pb significantly decreased bush bean yields in both control and DTPA treatments. The CaCO3 added to nutrient solution decreased the concentration of Pb in leaves, stems, and roots and prevented the toxicity of 10‐3 M Pb++. At high Pb levels, interactions between Pb and Mn and Pb and Fe were observed, except with CaCO3. In the soil experiment, the yields of barley and bush bean were influenced only slightly by Pb. The Pb concentration in ...

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.

Zinc induced iron deficiency in soybeans

Abstract When soybeans (Glycine max L. Merr. Bragg) were grown in solution culture, the PI54619–5–1 cultivar was Fe‐deficient when the Zn level was 10‐4 M. Iron contents in leaves were reduced by the high Zn level in the Hawkeye cultivar but less so than with the PI54619–5–1 cultivar. The high Zn resulted in depressed Fe contents in leaves, stems, and roots of both cultivars and in some direct effects of Zn toxicity with the Hawkeye cultivar. A high level of FeEDDHA (ferric ethylenediamine (di(o‐hydroxy‐phenylacetic acid)) partially overcame the Fe deficiency induced by a high Zn level.

Iron chlorosis caused by MgCO3

Abstract Plants wore grown in several experiments in which MgCO3 had been incorporated into soil. The MgCO3 with its high soil pH resulted in plants with Fe deficiency and this was partly overcome with Fe chelates. The disorder was also associated with low P and high Mg. When these problems were corrected, response to Fe chelates was more certain. Soil application of MgCO3 was inhibitory of growth and Fe uptake in both Hawkeye and PI54619–5–1 soybeans (Glycine max L.). Agricultural dolomite gave somewhat similar but slightly different response than MgCO3.

Zinc, nickel, and cadmium uptake and translocation to seed pods and their effects on gas exchange rates of bush bean plants grown in calcareous soil from the Northern Mojave Desert.

Abstract Bush bean plants (Phaseolus vulgaris L. cv. Improved Tendergreen) were grown in highly calcareous desert soil with high levels of Zn, Ni, and Cd added to them. The purposes were to compare growth and uptake with desert plants grown in the same soil, to assess translocation to fruits, and to measure gas exchange rates. All three trace metals produced toxicity in the highly calcareous soil and the bush beans were less tolerant than previously grown desert plants. The levels used at various points produced 50% or more yield decrease. Zinc and Ni were transported to fruits at concentrations considerably less than in leaves. The transport was greater for Ni than for Zn. Cadmium was not translocated to fruits in detectable quantities. Zinc and nickel supplied in excess restricted Cu movement to fruit. The levels of Zn and Ni had no influence on photosynthesis and transpiration, but the gas exchange rates were decreased by Cd on the dry weight basis.

Phosphorous levels on the ability of an iron‐inefficient and an iron‐efficient corn inbred to take up iron from nutrient solution

Abstract The Fe‐inefficient corn (Zea mays L.) inbred Ys1/YS1 was compared with the Fe‐efflcient WF9 inbred for ability to take up Fe from solution culture at different P levels. A high level of P depressed Fe uptake more in the Ys1/Ys1 than in the WF9 inbred. The Ys1/Ys1 roots were high in P.

Transfer values to fruits of Li in tomato and Cd in bush beans

Abstract Different levels of Li (10‐5, 10‐4, 5 x 1‐4 M) and Cd (2 x 10‐6, 10‐5, 10‐4 M) were studied in solution culture in a glasshouse to evaluate the effects on growth and fruit transfer values in tomato (Lycopersicon esculentum mill, cv. Marglobe) and bushbeans (Phaseolus vulgaris L. cv. Improved Tendergreen). No effect on yield was observed for up to 10‐4 M Li levels; after that yields were significantly decreased. The yield of bush‐beans was significantly reduced by the Cd levels added. The Li in solution culture significantly increased the Li concentration in tomato roots, leaves, and fruits. The Cd had an increasing effect on Cd concentration only in bushbean roots and a nonsignificant effect was observed in leaves and pods. Considerable amounts of Li were translocated to leaves and fruits while very little Cd was found in fruit pods. The exact amount was unknown due to limits of method.

A collander‐type experiment in large tanks of solution culture

Abstract Several different plant species were grown together in large (400 1) tanks of solution culture in the pattern of the original Collander experiment (Plant Physiol. 16:691) except in the present one, plants were spaced far enough apart that roots could not become entangled so that root‐shoot partitioning could be studied. Two sets of plants were grown in the tanks. One set was with agricultural species and the other was with native desert plants. One tank contained a standard nutrient solution and the second contained the same solution with addition of several cations: Na, Cd, Li, Ni, Cr, Pb, Sr, Ba. Plant species behaved differentially to the mixture of cations with differential partitioning among plant parts. Exclusion phenomena discussed in the original Collander paper are mostly retention in roots with little transloca‐tion to shoots. The extra cations in some cases increased yields, in some cases decreased yields with no differences in others. Several‐nutrient element interactions were indicat...

Effects of added Zn, Ni and Cd on desert shrubs grown in desert soil

Abstract Desert shrubs ‐ Ambrosia dumosa, Lycium andersonii, Larrea triden‐tata, and Ephedra nevadensis were grown in a glasshouse in desert (calcareous) soil with different levels of added Zn, Ni, and Cd. The objective was to study effects of the metals on growth and yield and uptake and trans‐location of metals in desert plant species which are common in the Mojave Desert (areas of Nevada and southeast California). Zinc and Cd considerably decreased yields of all four species. Yields of E. nevadensis were increased by Ni at 250 and 500 mg/kg applied to desert soil. Ephedra nevadensis was more tolerant of Ni than were the other three desert shrubs. Some interactions were observed among various elements: manganese concentration was increased in shrubs by Zn. Particularly, application of Ni reduced the concentrations of Zn and Mn over the control.

59Fe isotope dilution methods to determine labile Fe in soil and Fe uptake from fertilizer sources

Abstract The labile Fe in calcareous soils is probably divided into at least two fractions. One is readily available to plants and another is potentially available either upon extraction with dictating agent or upon interaction with soil or plant roots of species which are efficient in the mobilization and uptake of Fe. Equilibration of 59Fe in soil docs not result in a true measurement of labile Fe when plants are grown, but a close approximation can be obtained with use of a series of different levels of chelating agents with 59Fe equilibrated soils. Extrapolation to a zero level of chelating agents gives the amount of one fraction of labile Fe while the saturation point with high levels of chelating agent gives the amount of potentially available Fe. Differences in specific activity of DTPA (diethylene triamine pentaacetic acid) extracted Fe with that taken up by plants are partially explained by these effects. Different plants varying in susceptibility to Fe deficiency were grown in soil amended to gi...