A fresh look at resource assimilation and partitioning in cotton

Understanding the complex process of resource partitioning within the plant provides opportunities to develop new crop improvement strategies for varying environmental factors and agronomic practices. In upland cotton (Gossypium hirsutum L.), the partitioning of dry matter is as crucially important as that of macronutrients and micronutrients in improving yield. This dissertation compiles relevant reviews and studies that highlight the physiology of boll production and spatiotemporal distribution across plant and field scale levels as well as technological advancements in phenotyping that offer powerful and less input-requiring approaches that serve as additional layer for understanding the responses of cotton over a wide range of environmental and management factors. This dissertation also describes research works pertaining to the changes in macronutrient and micronutrient uptake and partitioning alongside with the remarkable improvements in modern cotton cultivars during the past few decades. Results demonstrated that the newer cultivars tested in this study were more efficient in partitioning and remobilizing nitrogen, phosphorus, potassium, sulfur, zinc, and copper into the developing boll and this increased efficiency translates to greater lint yield production for every unit of nutrient taken up compared to the earlier report in the 1990s. These improvements in nutrient uptake capacity in combination with the availability of high levels of residual soil N were able to sustain plant growth and maintain yield even under reduced nitrogen application. However, even with improved nutrient uptake efficiencies, growth and development could easily be hindered by slight differences in the availability of possible toxic elements such as sodium in the soil and irrigation sources. In summary, the changes in the patterns of assimilation and partitioning of carbon, macronutrients, and micronutrients within the cotton plant influences different aspects of crop adaptation, productivity, and survival. Therefore, it is important to have an utmost understanding of the mechanisms underlying these changes and how these mechanisms contribute to the interactions among genetics, environment, and management in order to maximize the potential of newer and soon-to-be developed cotton cultivars.

Embargo status: Restricted until 06/2022. To request the author grant access, click on the PDF link to the left.