The response of determinate and semi‐determinate faba bean varieties to different sowing dates in the spring

Abstract

SummaryField trials conducted during 1986 and 1987 at the University of Nottingham compared the growth and development of two varieties of faba bean, Alfred and Ticol, in response to three different dates of sowing in the spring.Grain yields were greater the earlier the crop was sown. This difference was attributed to the larger canopy size, especially at the pod‐filling stage of the earlier sown crops. This probably reflected the influence of temperature on the expansion and senescence of leaves during development.A semi‐determinate variety of faba bean, Alfred, yielded 31% more than a determinate variety, Ticol. This difference was not attributable to any particular yield component. In 1986, it was correlated with pods per podding node and in 1987 with the number of seeds per pod. Three reasons can be advanced to explain this greater yield. Firstly, Ticol branched more than Alfred and so a greater proportion of its total reproductive nodes were borne on the branches rather than the mainstem. Branches were shown to be inferior in terms of yield production. Secondly, it was demonstrated that Ticol was probably less able to transfer stored assimilates from the stem to the developing pod than Alfred. Thirdly, Alfred had a larger canopy during pod development than Ticol.