Temperature and atmospheric carbon dioxide concentration [CO2] affect cotton (Gossypium hirsutum L.) growth and development, but the interaction of these two factors on boll and fiber properties has not been studied. An experiment was conducted in naturally lit plant growth chambers to determine the influence of temperature and atmospheric [CO2] on cotton (cv. DPL‐51) boll and fiber growth parameters. Five temperature regimes were evaluated: the 1995 temperature at Mississippi State, MS; the 1995 temperature minus 2°C; and the 1995 temperature plus 2, 5, and 7°C. Daily and seasonal variation and amplitudes were maintained. Atmospheric [CO2] treatments were 360 (ambient) and 720 μL L−1. Boll number, boll growth, and fiber properties were measured. Boll size and maturation periods decreased as temperature increased. Boll growth increased with temperature to 25°C and then declined at the highest temperature. Boll maturation period, size, and growth rates were not affected by atmospheric [CO2]. The most temperature‐sensitive aspect of cotton development is boll retention. Almost no bolls were retained to maturity at 1995 plus 5 or 7°C, but squares and bolls were continuously produced even at those high temperatures. Therefore, the upper limit for cotton boll survival is 32°C, or 5°C warmer than the 1995 U.S. Mid‐South ambient temperatures. The 720 μL L−1 atmospheric [CO2] had about 40% more squares and bolls across temperatures than the 360 μL L−1 [CO2]. Fibers were longer when bolls grew at less than optimal temperatures (25°C) for boll growth. As temperature increased, fiber length distributions were more uniform. Fiber fineness and maturity increased linearly with the increase in temperature up to 26°C, but decreased at 32°C. Short‐fiber content declined linearly from 17 to 26°C, but was higher at higher temperature. As for boll growth and developmental parameters, elevated atmospheric [CO2] did not affect any of the fiber parameters. Changes in temperature, however, had a dramatic effect on boll set and fiber properties. The relationships between temperature and boll growth and developmental rate functions and fiber properties provide the necessary functional parameters to build fiber models under optimum water and nutrient conditions.

have the highest boll set and account for the majority of the yield. A change in boll distribution was noted when Early cotton (Gossypium hirsutum L.) planting in the Texas Coastal the growing season was characterized by lower tempera-Bend has the potential for improved performance through drought ture, less solar radiation, and higher precipitation amounts avoidance. This 2-yr field study was conducted to compare the effect of boll position on fiber properties across planting dates and to determine (Jenkins et al., 1990). how flowering date, boll position, and environmental factors affect During the first week after anthesis, fiber and outer fiber quality. Cotton ('Deltapine 5409') was planted early March, late integuments receive the greatest portion of photosyn-March, and mid-April each year. In 1997, lint yield for the early plantthate. After that, the distribution of photosynthate being date (731 kg ha Ϫ1 ) was significantly higher than the middle (622 tween the remainder of the seed and fiber is about equal. kg ha Ϫ1 ) and late (533 kg ha Ϫ1 ) planting dates. No significant differ-Fiber elongation begins 2 d after anthesis and continues ences in yield were found in 1999. Boll distribution patterns for middlefor an additional 3 to 4 wk. Around 15 d after anthesis, and late-planted cotton were similar. In 1997, the drier of the 2 yr, the deposition of a mainly cellulosic secondary wall befiber length and micronafis values increased at all boll locations with gins (Stewart, 1986). The degree of secondary-wall deearliness of planting while in 1999, the longest and most mature fiber position determines fiber maturity. Micronaire is a comwas associated with a number of boll locations in the middle planting date. High temperatures before and during boll development accom-posite measure of maturity and fiber fineness since fiber panied by adequate moisture increased fiber maturity.

No abstract

Early cotton (Gossypium hirsutum L.) planting in the Texas Coastal Bend has the potential for improved performance through drought avoidance. This 2‐yr field study was conducted to compare the effect of boll position on fiber properties across planting dates and to determine how flowering date, boll position, and environmental factors affect fiber quality. Cotton (‘Deltapine 5409’) was planted early March, late March, and mid‐April each year. In 1997, lint yield for the early planting date (731 kg ha−1) was significantly higher than the middle (622 kg ha−1) and late (533 kg ha−1) planting dates. No significant differences in yield were found in 1999. Boll distribution patterns for middle‐ and late‐planted cotton were similar. In 1997, the drier of the 2 yr, fiber length and micronafis values increased at all boll locations with earliness of planting while in 1999, the longest and most mature fiber was associated with a number of boll locations in the middle planting date. High temperatures before and during boll development accompanied by adequate moisture increased fiber maturity.

Developing and implementing a program to introduce clinical nurses to research and evidence-based practice (EBP) should spark interest and participation. In this article, the authors describe and evaluate a staff development initiative not only to introduce the principles of EBP and research but also to give nurses the opportunity to participate in the research process and development of EBP questions.