The causes of the lack of self-tolerance of winter rye, grown on light sandy soils. 2. Influences of phytotoxins and soil microflora.

Abstract

As a result of an investigation into the causes of self-intolerance of rye (i.e. of rye following rye) it could be proved that a number of obvious well-known pathological agents such as nematodes, foot rots and phytotoxins cannot be accepted as important causes. Circumstantial evidence was produced strongly suggesting that the composition of the soil microflora (to a certain extent itself the result of growing this crop in the previous yr) is the main cause. Soil sterilization eliminates self-intolerance. One symptom of self-intolerance is the rapid degeneration of the root system at an early stage of growth. Application of larger rates of N postpones the onset of this phenomenon. The effect of N is indirect. A larger continued uptake of N furthers the potential for compensation of the plant. (Abstract retrieved from CAB Abstracts by CABI’s permission)

The causes of the lack of self-tolerance of winter rye grown on light sandy soils. 3. Effects of soil funghi

“…To prove that fungi are the cause of self-intolerance of rye was precisely the aim of the experiment. We have thus confirmed the hypothesis we put forward in a previous publication (Schölte & Kupers, 1978).…”

“…A series of field and pot experiments indicated that neither foot rot, nematodes nor Phytotoxins could be important causes of this lack of self-tolerance (Schölte & Kupers, 1977, 1978. At the same time it became clear that the main cause ought to be found in the soil microflora.…”

A comparison of growing wheat continuously with growing wheat in a four-course rotation

“…There were marked seasonal differences, the largest effects on 1000-grain weight occurring in years when the difference in yield of the two forms of cropping was greatest. Scholte & Kupers (1978) made experiments to find the reasons for reduction of yield in winter rye when following a previous crop of rye, and review experiments with other cereals. Possible causes that have been put forward are nematodes, foot rots, phytotoxins and soil micro-organisms.…”