Average daily temperature at seeding is crucial in stand establishment. Average daily temperature is calculated by adding the daily high and low temperatures and dividing b 2. Remember: at or below 50 F, little or no rice seed germination will occur.
From 50 F to 55 F germination increases, but not to any great extent until temperature is above 60 F. Plant survival is not satisfactory until the average daily temperature is above 65 F.
Based on this information and seeding date research, recommended planting dates for Southwest Louisiana are March 15 - April 20.
Research at the Rice Research Station in Crowley has indicated that planting early produces the best yields regardless of variety planted.
In Dr. Steve Linscombe’s date of planting study, yields were significantly reduced after the late April planting.
Extremely early seeding can lead to a number of problems including (1) slow emergence and poor growth under colder conditions because of the inherent lack of seedling vigor and cold tolerance in many varieties, (2) increased damage from seedlings diseases under cool conditions, (3) increased damage from birds (blackbirds, ducks and geese) that are more numerous in the early spring and (4) interactions with herbicides.
Extremely late seedings can also be detrimental to yield. Stand establishment can be equally difficult in hot weather. The yield potential of many varieties will decrease significantly with later seedings.
Panicle blight is thought to be associated with higher than normal day and night temperatures during pollination and grain fill.
Late plantings are more likely to encounter these conditions. Also, many diseases (especially blast) and insect problems are more severe, and grain quality is often decreased with later-seeded rice.
To assure adequate time for a ratoon or second crop to develop prior to the onset of cold weather, the first crop should be harvested before mid-August.
Rice planted by or before April 15 in southwest Louisiana has the most potential for meeting this harvest deadline and producing good grain yields in the ratoon crop.
For more information, come by or call our office at 788-8821 or you can visit our website at GOTOBUTTON BM_1_ http://www.lsuagcenter.com.