Soybean Yield along the Texas Gulf Coast during Periods of Variable Rainfall as Influenced by Soybean Cultivar and Planting Date

W J Grichar,P Mcguill,J D Janak,S Biles

doi:10.1155/2011/314852

Abstract

Soybeans (Glycine max) can be planted along the upper Texas Gulf Coast from mid-March through May to take advantage of early season rains and to complete harvest before hurricane season and fall rains become a problem. When average to above average rainfall was received in May through July, yields were greater with the early April to mid-April planting; however, under high rainfall conditions throughout the season, the mid-April to early May planting produced the highest yields, with yields of over 4000 kg/ha. When rainfall was below normal, late March to early April plantings produced the greatest yields. When rainfall was above average, soybeans took longer to reach harvestability regardless of cultivar or plant dates, while under drought conditions the interval between planting and harvest was reduced. However, when planting was delayed, there was a greater risk of detrimental late-season effects from southern green stink bug (Nezara viridula) or the brown stink bug (Euschistus heros).

Highlights

Soybeans (Glycine max) are grown along the upper Texas Gulf Coast and this area has become the largest soybean production area in the state
Most of the soybeans are planted from mid-March through May and are categorized as early soybean production system (ESPS) plantings
The above normal rainfall for the respective dates in 2008 came too late to be of any help during the 2008 growing season

Summary

Introduction

Soybeans (Glycine max) are grown along the upper Texas Gulf Coast and this area has become the largest soybean production area in the state. Most of the soybeans are planted from mid-March through May and are categorized as early soybean production system (ESPS) plantings. Stress can reduce soybean yield by reducing the number of pods, seeds, and seed mass [7, 8] Both determinate and indeterminate soybean cultivars have reduced growth rates under drought stress and resume normal growth rates when such stress is removed [8]. This may be an important growth attribute to consider if producers expect considerable soil moisture deficits due to short, intermittent droughts during the growing season [5]

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