Contribution of Boll Mass and Boll Number to Irrigated Cotton Yield

Abstract

The production of fruit on upland cotton (Gossypium hirsutum L.) varies with environment, cultivar, and management practices, including irrigation. Yield increase in response to irrigation is a combination of additional boll production on the plant and differences in the size of individual bolls. Previous research on this subject is incomplete. The purpose of this research was to compare the effects of irrigation on boll distribution and boll size in four cotton cultivars in West Texas. Boll distribution and boll mass in response to 10 daily irrigation levels (0–6.5 mm d−1) were compared among four cultivars with varying maturities [‘Deltapine 1212 B2RF’ (DP1212), ‘Deltapine 1219 B2RF’ (DP1219), ‘FiberMax 2484 B2F’ (FM2484), and ‘FiberMax 2011 GT’ (FM2011)] from 2011 to 2013 in Lubbock, TX. Boll production and retention followed cultivar‐specific patterns in all 3 yr. Two cultivars (DP1212 and FM2011) produced fruit primarily at the bottom and middle of the plant, one had increased production high on the plant (DP1219), and one produced fruit almost exclusively in the middle of the plant (FM2484). Both boll number and boll mass contributed to lint yield, with boll number being the major determinant (on average, 90%) of lint yield, whereas boll mass accounted for 10% of lint yield on average. The contribution of boll number and boll size to yield varied among cultivars and did not appear to be wholly maturity‐related. Research studies focused on boll number should be aware that boll distribution does not account for all of the variation in yield.

Using Normalized Difference Red Edge Index to Assess Maturity in Cotton

“…In 2016, boll distribution tended toward lower nodes compared with 2017. This effect was also observed by Sharma et al (2015a), in which the hotter temperatures and low rainfall in the 2011 growing season caused the plants to set more fruit on comparatively lower nodes. The opposite occurred in 2017, in which boll distribution tended toward middle nodes with some additional fruit set on upper nodes.…”

“…Many of the later-maturing cultivars had higher NDRE values than other cultivars later in the season. Most early-maturing cultivars are shorter in stature and tend to produce the majority of their fruit on lower nodes as compared to later-season cultivars, which tend to produce more vegetative growth earlier in the season and have the majority of their fruit on the middle to upper nodes (Sharma et al, 2015a).…”

Shading and Nitrogen Effects on Cotton Earliness Assessed by Boll Yield Distribution

“…The term "earliness" represents the fast development or maturation of the harvestable cotton crop relative to the available growing season (Oosterhuis et al, 2008). In turn, although there is little consensus on the definition, cotton maturity is a measure related to the duration of fruiting and the time for the crop to produce a particular fraction of its commercial yield (Sharma et al, 2015). The earliness of crop maturity is a major factor contributing to yield components, fiber quality, and costs of production.…”

Cotton Maturity Determination through Vertical Mapping

“…Because bolls are hand harvested and separated based on fruiting site and developmental date, it is possible to measure fiber quality by fruiting site throughout the sample (Feng et al, 2010). This method of plant mapping has recently become more widespread and is a popular way to map the fruiting distribution of cotton (Ritchie et al, 2009;Sharma et al, 2015).…”