FACTORS AFFECTING THE GERMINATION AND ESTABLISHMENT OF MONOGERM SUGAR BEET


2.4.5       Field emergence

Aura (1975) categorised four factors involved in emergence:

1)         The germination energy of the seed.

2)         The appearance of pathogens.

3)         Mechanical soil resistance.

4)         Soil, air & water content.

 

(i)         Germination Energy.  Perry (1973) showed monogerm final emergence to be reduced by high soil water levels and by compaction, but not by low soil temperature.  However, seed lots responded differently showing that seedling vigour is important.

(ii)       Effect of fungicide.  Heydecker & Chetram (1971) showed that seed fungicide treatment improved field performance even if laboratory tests showed the reverse.

(iii)      Hegarty and Royle (1978) measured the impedance of soils covering sugar beet seeds and showed a negative linear correlation with final emergences.  Perry (1973) also showed how soil capping caused by irrigation water reduced emergence by 30%.

(iii)           Aura (1975) considered oxygen uptake was only seriously hindered by water in the seed or the surrounding film, when soil water potentials were close to zero, i.e. in very wet soils.  Poor contact between soil and seed could reduce germination by restricting water uptake in dry soils, if the soil water potential and was less than - 10 atm no emergence occurred.  Aura also noted water diffusion to be slower through the seed than through the soil.  Pelleted seed emerges better in wet soil conditions (Perry 1973), and Hibbert et al (1975) postulated that pelleted seed may have a higher water requirement and should be sown slightly deeper in dry conditions.  Aura (1975), however found pellets restricted oxygen uptake in very wet conditions.


Learn more about pre-sown
seed technology applications


[Last Section]     [Next Section]

FACTORS AFFECTING THE GERMINATION AND ESTABLISHMENT OF MONOGERM SUGAR BEET

[Introduction & Contents]     [Chapter One]     [Chapter Two]     [Chapter Three]     [Chapter Four]     [Chapter Five]     [Chapter Six]     [Chapter Seven]

[2.4]     [2.4.1]     [2.4.2]     [2.4.3]     [2.4.4]     [2.4.5]     [2.4.6]     [2.4.7]     [2.4.8]