[Abstract] Light attenuation within a row of crops such as cotton is influenced by canopy architecture, which is defined by size, shape and orientation of shoot components. Level of light interception causes an array of morpho-anatomical, physiological and biochemical changes. Physiological determinants of growth include light interception, light use efficiency, dry matter accumulation, duration of growth and dry matter partitioning. Maximum light utilization in cotton production can be attained by adopting cultural practices that yields optimum plant populations as they affect canopy arrangement by modifying the plant canopy components. This paper highlights the extent to which spatial arrangement and density affect light interception in cotton crops. The cotton crop branches tend to grow into the inter-row space to avoid shade. The modification of canopy components suggests a shade avoidance and competition for light. Maximum leaf area index is obtained especially at flowering stage with higher populations which depicts better yields in cotton production.
[Keywords] Light interception, Plant populations, Spatial arrangement, Canopy architecture
[Title] The impact of plant density and spatial arrangement on light interception on cotton crop and seed cotton yield: an overview
[Authors] CHAPEPA Blessing, MUDADA Nhamo & MAPURANGA Rangarirai
Journal of Cotton Research 2020, 3: 18
Issue 4 of GOSSyP is now available
[Abstract] Gossypium hirsutum, the most widely planted cotton species, its evolution has long been an unsolved puzzle because of its hybrid origin from D-genome and A-genome species. To better understand the genetic component of cotton, Huang et al. recently sequenced and assembled the first A1-genome G. herbaceum, and updated the A2-genome G. arboreum and (AD)1-genome G. hirsutum. On the basis of the three reference genomes, they resolved existing controversial concepts and provided novel evolutionary insights surrounding the A-genome.
[Title] Unraveling the puzzle of the origin and evolution of cotton A-genome
[Authors] MA Zhiying
Journal of Cotton Research 3, Article number: 17 (2020)
[Background] This study addressed the potential of combining a high biomass rye winter cover crop with predawn leaf water potential (ΨPD) irrigation thresholds to increase agricultural water use efficiency (WUE) in cotton. To this end, a study was conducted near Tifton, Georgia under a manually-controlled, variable-rate lateral irrigation system using a Scholander pressure chamber approach to measure leaf water potential and impose varying irrigation scheduling treatments during the growing season. ΨPD thresholds were − 0.4 MPa (T1), − 0.5 MPa (T2), and − 0.7 MPa (T3). A winter rye cover crop or conventional tillage were utilized for T1-T3 as well.
[Results] Reductions in irrigation of up to 10% were noted in this study for the driest threshold (− 0.7 MPa) with no reduction in lint yield relative to the − 0.4 MPa and − 0.5 MPa thresholds. Drier conditions during flowering (2014) limited plant growth and node production, hastened cutout, and decreased yield and WUE relative to 2015.
[Conclusions] We conclude that ΨPD irrigation thresholds between − 0.5 MPa and − 0.7 MPa appear to be viable for use in a ΨPD scheduling system with adequate yield and WUE for cotton production in the southeastern U.S. Rye cover positively impacted water potential at certain points throughout the growing season but not yield or WUE indicating the potential for rye cover crops to improve water use efficiency should be tested under longer-term production scenarios.
[Title] Applying plant-based irrigation scheduling to assess water use efficiency of cotton following a high-biomass rye cover crop
[Authors] MEEKS Calvin D., SNIDER John L., CULPEPPER Stanley and HAWKINS Gary
Journal of Cotton Research 3, Article number: 16 (2020)