Canopy Light Environment and Yield of Narrow‐Row Cotton as Affected by Canopy Architecture

Abstract

Alterations of plant architecture in narrow‐row cotton (Gossypium hirsutum L.) using management and genetic strategies to improve light penetration into the canopy may increase crop yields. The objective of this study was to quantify how plant architecture changes affect light penetration into the canopy, yield, and yield components of narrow‐row cotton. The study was conducted on a Glendale clay loam soil (fine montmorillonitic, thermic Typic Torrert). Two field experiments were established on 0.76‐m rows in 1995 and 1996. Treatments consisted of the following plant architecture modifications: pruning leaves throughout the canopy, mechanical topping, trimming of branches, and temporarily opening the canopy during boll production. Photosynthetic photon flux density (PPFD) interception and PPFD penetration into the canopy were measured when the canopy was fully developed. Seed‐cotton yield and yield components by plots, fruiting positions, and strata by four main‐stem node groups were obtained. Early canopy modifications simulating plant characteristics such as reduced plant height, short branches, and modified leaf shape increased light availability at the medium and upper part of the canopy. Modified canopy treatments grown at 97 000 plants ha−1 reached high PPFD interception (90–97%), with leaf area index from 3.7 to 5.2. Treatments to increase light distribution in the canopy while maintaining a high PPFD interception increased seed‐cotton yield by 34% due to a 26% increase in number of bolls per square meter. A canopy light environment improved during the first 3 wk after canopy closure (86–107 d after sowing) increased number of bolls per square meter by 33%.

Effect of plant density on yield and physiological characteristics of six canola cultivars

“…This phenomenon may result from tight competition of plants for water, light, and nutrient under high plant density, thus increasing the amount of proline. Reta-Sanches and Fowler (2002) suggested that changing plant densities and increasing light penetration in lower parts of the canopy can improve plant yield. In the present study, seed yield decreased with increasing plant densities (60 plants m -2 ) for all canola cultivars, which possibly resulted from reduction of light penetration under high plant densities.…”

Effect of plant spacing and fertility level on leaf area variation at different phenological stages of cape gooseberry (Physalisperuviana L.) grown in sodic soil

“…(1997) reported that planting density did not affect the leaf area in tomato. While increasing the plant populations per unit area, intra-plant competition becomes more important and light interception also varied with crop development; the planting pattern optimises the available natural and unnatural resources and row spacing become important in crop canopy structure (Andrade et al, 2002;Reta-Sanchez and Fowler, 2002;Sharratt and McWilliams, 2005). The state of development of the plant determines the pattern distribution of dry matter in different organs of the plant, and the leaf area growth determines the light interception pattern (Heuvelink and Marcelis, 1989).…”

Manipulation of dry matter accumulation and partitioning with plant density in relation to yield stability of cotton under intensive management

“…The economic yield of cotton is basically influenced by the balance of assimilate allocation between vegetative and reproductive organs (Reta-Sánchez and Fowler, 2002;Jones et al, 1996;Kerby et al, 1993). In China, intensive farming technologies involving plastic mulching, plant topping and pruning have been widely adopted for cotton production in the last 40 years (Dai and Dong, 2014).…”