Factors influencing flower and pod development in oil-seed rape (Brassica napus L.)

Abstract

Experiments were carried out on oil-seed rape, variety Zollerngold, to determine the effects on flower and pod development when (1) the supply of carbon assimilates was reduced by shading or leaf removal at different stages of development or (2) the supply of assimilates to the more apically positioned flowers or pods on the terminal raceme was increased by removing 15 of the most basal flowers or pods.A decrease in the production of carbon assimilates led to fewer flowers and pods developing to maturity and when the stress continued over most of the period of pod development the pods were smaller and had fewer seeds which were also lighter in weight.Removal of the 15 basal flowers or pods led to more of the apically positioned flowers developing into mature pods and the other pods becoming heavier with bigger husks, heavier seeds and sometimes a greater number of seeds.The results of a shading experiment in a controlled environment cabinet suggest that stresses in the supply of carbon assimilates around the time of anthesis are particularly harmful since in addition to reducing the number of pods which develop they appear to restrict the capacity for compensatory growth in the pods that remain when the supply returns to normal.

Canola response to high and moderately high temperature stresses during seed maturation

“…Pod number and seed number per pod were unaffected by the heat treatments, since they were imposed 20 to 25 DAF, probably after the period of determination of these components which is 2 to 3 wk after flowering (Tayo and Morgan 1979;Mendham and Salisbury 1995).…”

In Vitro and In Vivo Management of Alternaria Leaf Spot of Brassica campestris L.

“…Its oils contain low erusic acid and glucosinolates contents. The percentage of poly-unsaturated fatty acid and linolenic acid of the total fatty acid increase from 15-0% and from 8-12%, respectively [3].…”

The effect of rapeseed stand density on the formation of generative organs

“…The creation and distribution of seed yield on the primary racemes and on the primary branches of rapeseed are well documented (Tayo andMorgan 1979, Daniels et al 1983), but the dynamic of the relationship between individual branches is unknown. The compensation abilities of lower branches, especially of branches of lower grade, are not quantified.…”

“…The accessibility of assimilates before and during the flowering period is the limit for the creation of flowers (Tayo and Morgan 1979) and the total number of flower is limiting the yield potential (Mendham et al 1981). The realization of this potential is limited by the fall of flowers Scott 1975, McGregor 1981).…”

“…As soon as the main components of the future yield are installed, i.e. the earliest developed generative organs, the yield is constituted mainly by flowers, which develop in the first 10 days from the beginning of flowering (Tayo andMorgan 1979, Tittonel 1991) the reduction of the later created generative organs takes place (Bilsborow and Norton 1984). The primary racemes and primary branches have in general more fertile pods and they are from the point of view of the seed yield more productive (Daniels and Scarisbrick 1983).…”