Emergence force exerted by wheat seedlings

Emergence ability, an important aspect of wheat (Triticum aestivum L.) establishment, was examined because low yields are often related to poor stands. The force exerted by the emerging wheat seedlings was estimated using two methods: (1) direct measurement; and (2) displacing obstacles of different sizes. The results showed that the maximum force exerted by the wheat coleoptile (cultivar ‘Nesma 149’) was about 30 g. Final emergence percentage was about 100% when the weight of the obstacles was less than 25 g and decreased linearly with increasing obstacle weight. From these results, it was determined that an ideal seedbed for wheat would have clods with a maximum size of 30 mm in diameter.