Minimizing Immature Fiber and Neps in Upland Cotton

Abstract

Immature cotton (Gossypium hirsutum L.) fi bers and neps in ginned cotton will aff ect textile quality and thus can aff ect overall industry reputations. Th is study conducted three fi eld studies that systematically varied the timing of harvest aid application to generate diff erences in the amount of immature fi ber and levels of neps in crops at harvest. Th e aim was to ascertain what crop conditions (percent open bolls, number of immature bolls, percent immature bolls, and percent immature lint mass) at the time of application contribute to these diff erences, and assess whether these outcomes are infl uenced by 0, 1, 2 lint cleaning passes. Earlier harvest aid treatments increased neps and the level of neps was best related to fi ber linear density (r 2 = 0.78). All measurements of crop condition at harvest aid application explained changes in yield and fi ber properties well, although the percent immature bolls (r 2 > 0.67) can be applied when crops are nonuniform in their maturity, and when they contain fruiting gaps. Relationships between lint cleaning passes and crop condition at harvest aid application showed an interaction between earlier harvest treatments and lint cleaning passes. One lint cleaning pass contributed between 95 and 141 count g −1 more neps, while a second pass added between 101 and 181 count g −1 more neps. Th is information will be valuable in refi ning strategies that aim to optimize both yield and fi ber quality (including less neps). Th is study also supported the current recommendation of applying harvest aids at 60% open bolls.

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

“…the total from two or more sequential harvests (Harris and Smith, 1980;Kerby et al, 1990;Munir et al, 2015), the proportion of bolls harvested on early-fruiting sites (Fry, 1985), the nodes above the white flower (McConnell et al, 1993), the node number of the first fruiting branch (Ray and Richmond, 1966;Kerby et al, 1990), the percentage of open bolls (Snipes and Baskin, 1994;Bange et al, 2010), and the nodes above the cracked boll (Bednarz et al, 2002;Faircloth et al, 2004;Bange et al, 2010). The aim of this work was to evaluate the effect of shading at early flowering and N top-dressing rates on relative cotton earliness using plant mapping.…”

Genetic Mapping in Cotton

“…Ultimately, the course fiber makes relatively weaker yarn. It is one of the reasons that high micronaire cotton is less preferred by the spinners due to reduced fiber bundle strength [133]. Less micronaire value < 3.5 μg/inch of lint is also undesirable as it reflects the immature fiber which may prone to dye uptake problems, breakage and neps formation.…”

“…For example, temperature, plant defoliation [133][134][135], radiation [136,137] and water stress [138] significantly impact the micronaire value. Thus, understanding the extent that these factors affect the micronaire value is important for undertaking cultural practices to produce cotton fiber with desirable micronaire value.…”

Cotton Maturity Determination through Vertical Mapping

“…The measurement NACB is defined as the number of mainstem nodes above the highest first-position cracked boll. It has been proven on multiple occasions that, at four NACB, a cotton plant will have at least 60% open bolls (Bednarz et al, 2002;Faircloth et al, 2004;Bange et al, 2010). Plants that have four or less NACB are considered mature enough to receive harvest-aid applications without the risk of extensive loss of yield or micronaire values to fiber quality (Kerby et al, 1992Bange et al, 2010).…”

“…Bolls are considered cracked when lint is visible through fissures in the carpel wall (Kerby et al, 1992). Plants that have four or less NACB are considered mature enough to receive harvest-aid applications without the risk of extensive loss of yield or micronaire values to fiber quality (Kerby et al, 1992Bange et al, 2010). It has been proven on multiple occasions that, at four NACB, a cotton plant will have at least 60% open bolls (Bednarz et al, 2002;Faircloth et al, 2004;Bange et al, 2010).…”