Effect of Seed Meals on Weed Control and Soil Physical Properties in Direct-Seeded Pumpkin

Rupinder Saini,Atinderpal Singh,Sanjit K Deb

doi:10.3390/su12145811

Abstract

Mustard (Brassica sp.) seed meal (MSM) and sunflower (Helianthus annuus L.) seed meal (SSM) are the byproducts of the seed oil extraction process. They release biologically active allelochemicals that can provide a resource for supplemental nutrients and weed suppression in vegetable cropping systems. Our field experiment aimed to assess the phytotoxic impact of MSM and SSM on weeds and seedling establishment of direct-seeded pumpkin under semi-arid conditions and to study the impact of MSM and SSM on soil physical properties and soil water retention characteristics. The meals were incorporated into the soil 2 weeks before pumpkin planting at two rates (1150 and 2250 kg ha−1). MSM at both rates reduced early season grass and broadleaf weeds by 75 to 82% and 69 to 76%, respectively, as compared to the untreated control. However, SSM at both rates provided 59 to 65% and 54 to 59% controls of narrow and broadleaf weeds, respectively. Both MSM and SSM provided significantly better weed control and pumpkin yield as compared to the untreated control, but higher pumpkin yield was recorded with a lower rate of MSM. In addition, soils amended by both the seed meals had higher saturated hydraulic conductivity, soil water content, and lower bulk density than the untreated control. Overall, our findings suggest that the use of both MSM and SSM as an organic adjuvant is effective in controlling weeds and improving soil physical properties; however, additional research is required to further evaluate these findings and improve the reliability of MSM and SSM for weed suppression following application to agricultural soils.

Highlights

Pumpkin (Cucurbita pepo L.) is one of the major specialty crops in the United States and it is produced in almost all the states of the country [1]
Our results indicate that the application of Mustard Seed Meal (MSM) or Sunflower Seed Meal (SSM) at or below 2250 kg ha−1 two weeks before planting is safe to use in direct-seeded pumpkin
The results of this study using both MSM and SSM as pre-emergence soil amendments at different rates for controlling weed and improving soil physical properties in direct-seeded pumpkin production suggested that the best overall weed control could be achieved with an application of 2250 kg ha−1 of MSM. Both MSM and SSM provided significantly higher early season weed control than the untreated control. The effectiveness of both the seed meals decreased with time, except the higher rate of MSM

Summary

Introduction

Pumpkin (Cucurbita pepo L.) is one of the major specialty crops in the United States and it is produced in almost all the states of the country [1]. The West Texas region is characterized as semi-arid with an average annual rainfall of 400 mm and high evaporative demand of approximately 2500 mm per year [3] These weather conditions in the past forced growers to pump significant amounts of water for supplemental irrigation [4,5]. The monoculture has allowed growers to be specialized (requiring fewer pieces of equipment) in their farming operations, which helped them to produce a crop at larger volumes [6] These intensive monoculture practices for the past 4–5 decades have increased weed seed bank and deteriorated the environment, especially the soils on which an economically and ecologically viable agriculture depends. The most prominent risks for sustainable and secure food production are increasing crop pests and declining soil health

Objectives

Methods

Results

Conclusion