Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 22, 2009
Publication Date: September 1, 2009
Citation: Pettigrew, W.T., Molin, W.T., Stetina, S.R. 2009. Impact of Varying Planting Dates and Tillage Systems on Cotton Growth and Lint Yield Production. Agronomy Journal. 101:1131-1138. Interpretive Summary: Inputs for producing all row crops have increased dramatically during the past few years, while the price received for cotton has remained flat or declined. Because of this squeeze on their profit margins, cotton producers have looked for methods to reduce inputs while maintaining yield performance. Minimum tillage offers input reductions by reducing the number of times tillage equipment has to be pass over a field. Early planting, on the other hand, has been documented to often produce yield advantages over later planting dates. An issue with both practices is that the seed can potentially be planted into cool conditions that challenge stand establishment. This study investigated how the combination of early planting with minimum tillage compared to more traditional planting strategies (later planting with conventional tillage) for cotton growth and development, lint yield, and fiber quality. Although early planting produced a yield increase in only one of four years, it never caused a yield decrease when compared to later planting. This response was also consistent across both tillage systems. Unfortunately, minimum tillage resulted in a yield decrease during the last 2 years of this 4 year study. Even though a yield penalty was occasionally incurred with minimum tillage, the pairing of minimum tillage with early planting could prove to be an economically viable option for producers because of the input reductions associated with minimum tillage. These results will be especially informative to producers, consultants, and extension personnel when devising cotton production strategies to minimize input reductions while maintaining yield production levels.
Technical Abstract: As economic conditions have deteriorated, cotton (Gossypium hirsutum L.) producers have looked to improve profit margins by reducing inputs while maintaining yields. Pairing the yield benefits from early planting with the input reductions from conservation tillage might be a strategy to accomplish those goals. The objective of this research was to determine how growth, yield production, and fiber quality were impacted by planting cotton early while also using minimum tillage. Four cotton cultivars were planted either during the first week in April (Early) or the first week in May (Normal) in 2004-2007. Half the plots were conventional tillage and the other half were minimum tillage. Dry matter partitioning, flowering, root hydraulic conductance, leaf water potential, lint yield, yield components, and fiber quality data were collected. Cultivars differed in leaf water potential, leaf osmotic potential, and root hydraulic conductance. The root hydraulic conductance for the early planting was 21% greater than the normal planting, but no differences were detected between tillage treatments. Early planting increased lint yields 22% in 2007, but yields did not differ between planting dates any of the other years. During the last two years of the study, lint yields were reduced 13% when minimum tillage was employed. No planting date * tillage treatments interactions were detected, so the same response to minimum tillage could be expected regardless of whether the planting occurred in early April or early May. Even though yield reductions were occasionally observed with minimum tillage, the pairing of minimum tillage with early planting could be a viable option for producers because of the input reduction.