Compatibility of 2‐Chloro‐6‐(Trichloromethyl) Pyridine with Medicago sativa L. Inoculated with Rhizobium meliloti¹

Abstract

Synopsis Greenhouse tests indicated no reduction in the survival of Rhizobium meliloti on alfalfa seeds and in soil fertilized with ammonium sulfate treated with 2‐chloro‐6‐(trichloromethyl) pyridine. Reduction in seedling growth of alfalfa plants was severe at 20 ppm of 2‐chloro‐6‐(trichlorornethyl) pyridine and slight at 1 ppm. Other deleterious effects on alfalfa seedlings were changes in nodule morphology and deformation of root tips.

Toxicity of 2‐Chloro‐6‐(Trichloromethyl) Pyridine in Soybean (Glycine Max L. Merr.) Seedlings1

“…In view of the effects of N-Serve on root growth it has been suggested that it may affect nutrient uptake (4). There was no significant effect of N-Serve on the percentage of K, Mg, and Ca in the shoots and roots in this experiment, although the total uptake of the cations at the high N-Serve concentrations was reduced clue to the reduction in plant growth.…”

Comparative Phytotoxicity of Nitrapyrin and its Principal Metabolite, 6‐Chloropicolinic Acid

“…Because 6chloropicolinic acid is the initial and principal metabolite present after the application of nitrapyrin, some of the phytotoxicity observed in studies conducted with nitrapyrin is probably due to 6-chloropicolinic acid. This would seem to be the case in instances where auxin-type symptoms have been observed with leguminous plants (6,7,12,13).…”

“…Results obtained in several laboratory studies, however, have shown that nitrapyrin applied to soil can produce phytotoxicity, and that the nature and sev-erity of the phytotoxicity depends to a large extent upon the concentration of nitrapyrin as well as the plant species and soil in question (6,7,9,12,13). Legumes such as alfalfa (Medicago sativa L.) (7), black locust (Robinia pseudoacacia L.) (6,12), and soybean [Glycine max (L.) Merr.] (13) are sensitive.…”

Kinetics of Nitrification in Selected Iowa Soils Treated with Stay‐N 2000

“…We conducted experiments to determine the rates of Stay-N 2000 required for total inhibition nitrification in two Iowa soils that differ in soil organic C and soil pH (Table 1) McKell and Whalley, 1964;Riley and Barber, 1970;Sander and Barker, 1978), our findings suggest that higher rates of Stay-N 2000 are required to reduce NOg -N accumulation ( Fig. 3) and rapid NH 4 + -N depletion (Table 3) in the soil with high pH and soil organic matter contents.…”