Crop & Pest Report

Accessibility


| Share

2015 Sunflower Survey Results (05/19/16)

During the 2015 sunflower growing season, 14 trained teams - including agronomists, entomologists, pathologists, crop consultants and/or producers - randomly stopped at 106 sunflower production fields in ND. Each team evaluated plant density, yield potential, disease, insect, and weed issues for each field.

2015 Sunflower Survey Results

During the 2015 sunflower growing season, 14 trained teams - including agronomists, entomologists, pathologists, crop consultants and/or producers - randomly stopped at 106 sunflower production fields in ND. Each team evaluated plant density, yield potential, disease, insect, and weed issues for each field.

A yield estimate was calculated based on plant density, head size, seed size, seeds per head and percent loss due to bird feeding. The yield for 2011-2015 and plant density (multiply number by 10) are indicated in Table 1. The yield averaged across the 4 years was 1,709 pounds per acre with 17,100 plants per acre. The counted plant density was lower than optimum and increasing the established number of plants per acre, with an even distribution, may provide an opportunity to increase sunflower yield in ND.plsc.1.sunflower

Determination of yield-limiting factors was based on the surveyors’ judgment after considering all productions aspects in the field. Table 2 shows the most-limiting and second most-limiting factors for the period 2011 through 2015. The results of the survey do not include events that took place after the survey, for instance additional bird damage or lodging.

Overall, the most yield limiting factor in 2015 was diseases followed by lodging and plant spacing (within the row) and drought. The diseases of most concern in the survey were sunflower rust and Phomopsis stem canker. In 2015, sunflower rust incidence (percent of fields in which rust was found) was 63 percent in ND.  Phomopsis stem canker was the 2nd most prevalent yield limiting disease, occurring in 56 percent of surveyed fields, and was more prevalent than Sclerotinia head rot, which was seen in only 20 percent of fields.

plsc.2.sunflower

The plant spacing difficulties consisted of large skips within the row, or areas where plants grew too close together, causing some of the plants not to contribute to the sunflower yield. Equal distribution of plants is essential to obtaining maximum sunflower seed yield. Irregular plant distribution may have been caused by poor seeding conditions, failure to adjust the planter, driving too fast, poor germination, disease, insect damage, or other factors.  Producers should pay attention to the plant spacing issue and planter calibration may be the first step to reducing skips and achieving more uniform plant spacing. Producers should also pay attention to the seeding rate as on average in ND the number of plants per acre was below plant densities needed to reach optimum yield.

In 2015 “no limiting factor” could be determined in 13 percent of the fields. The “no problem” category indicates that the evaluators felt the field reached its maximum yield potential for the 2015 growing season.

Hans Kandel

Extension Agronomist Broadleaf Crops

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.