Reproductive and Fiber Quality Responses of Upland Cotton to Moisture Deficiency

Abstract

Quantitative information between water deficit and cotton (Gossypium hirsutum L.) reproductive potential and fiber quality is needed to improve cotton model predictability. An experiment was conducted by seeding Upland cotton cultivar, Texas Marker (TM)-1, in sunlit growth chambers. Four water stress treatments, 100, 80, 60, and 40% of daily evapotranspiration of the control, were imposed during flowering for plants grown at optimum temperature and nutrient supply. Soil moisture content and midday leaf water potential (LWP) were measured twice weekly during treatment period. Photosynthetic measurements taken during the stress treatments were correlated with midday LWP. New flowers and bolls were tagged daily to estimate boll maturation period (BMP). Plant-and boll-component dry weights were recorded at end of the experiment. Lint sample collected, grouped based on average LWP during BMP, were analyzed for fiber quality parameters. Declining photosynthetic rates as plants experience water deficits were mostly to stomatal limitation, but non-stomatal factors played a role as stress progressed. Seedcotton and seed weight, boll numbers, and total biomass declined significantly at severe water deficit treatments reflecting declining trends of photosynthesis. Fiber length, strength, and uniformity declined linearly with decrease in LWP, whereas fiber micronaire increased with decrease in LWP. Fiber strength was most responsive to changes in LWP followed by micronaire, length, and uniformity. Immature fiber content increased and fiber maturity ratio declined with diminishing LWP. The functional relationships between LWP and fiber properties will be useful to develop fiber sub-models under optimal temperature and nutrient, but varying moisture conditions.

Quantifying Temperature Effects on Cotton Reproductive Efficiency and Fiber Quality

“…The identified temperature‐specific fiber quality indices can be incorporated in cotton simulation models to improve management practices under present and future enhanced temperature levels (Thorp et al, 2014; Liang et al, 2012). However, the influence of soil moisture stress (Lokhande and Reddy, 2014) and nutrients (Reddy et al, 2004) are needed to account other stresses in the production environment with variable weather, soil moisture, and nutrient conditions (Snowden et al, 2013). The resulting improved cotton models would be useful for optimizing production decisions such as planting dates for maximum yield and optimum fiber quality and also assist in providing guidance to natural resource management and policy decisions including global climate change with respect to cotton production.…”

Sweetpotato Responses to Mid‐ and Late‐Season Soil Moisture Deficits

“…2). (Siddique et al, 2000), cassava (Manihot utilisima Pohl) (Ike and Thurtell, 1981), and cotton (Gossypium hirsutum L.) (Lokhande and Reddy, 2014). They further reported that the midday LWP in sweetpotato plants grown in open-top chambers under well-watered and water-stressed conditions for 14 d had LWPs of -0.75 and -1.5 MPa, respectively.…”

“…Interrelationships between plant processes and LWP and soil moisture deficit have been well documented for other crop species such as wheat (Triticum spp.) (Siddique et al, 2000), cassava (Manihot utilisima Pohl) (Ike and Thurtell, 1981), and cotton (Gossypium hirsutum L.) (Lokhande and Reddy, 2014).…”

Registration of ‘Tamcot G11’ Upland Cotton Cultivar

“…Reduced yield potential is generally recognized as a result of drought, but moisture stress has an impact on fiber quality as well. Lokhande and Reddy (2014) reported that fiber length (upper half mean length [UHML]), fiber bundle strength (Str), and fiber length uniformity (UI) decreased linearly with increasing moisture stress under growth chamber conditions. UHML decreased from 33 mm at 100% evapotranspiration (ET) replacement/−1.6 MPa leaf water potential to less than 28 mm at 40% ET replacement/−2.4 MPa leaf water potential.…”