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Growth chamber experiments were conducted to study the physiological and growth response of peanut (Arachis hypogaea L.) to 50% and 85% relative humidity (RH). The objective was to determine the effects of RH on pod and seed yield, harvest index, and flowering of peanut grown by the nutrient film technique (NFT). `Georgia Red' peanut plants (14 days old) were planted into growth channels (0.15 × 0.15 × 1.2 m). Plants were spaced 25 cm apart with 15 cm between channels. A modified half-Hoagland solution with an additional 2 mm Ca was used. Solution pH was maintained between 6.4 and 6.7, and electrical conductivity (EC) ranged between 1100 and 1200 μS·cm–1. Temperature regimes of 28/22 °C were maintained during the light/dark periods (12 hours each) with photosynthetic photon flux (PPF) at canopy level of 500 μmol·m–2·s–1. Foliage and pod fresh and dry weights, total seed yield, harvest index (HI), and seed maturity were greater at high than at low RH. Plants grown at 85% RH had greater total and individual leaflet area and stomatal conductance, flowered 3 days earlier and had a greater number of flowers reaching anthesis. Gynophores grew more rapidly at 85% than at 50% RH.

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`Georgia Red' peanut (Arachis hypogaea L.) was grown hydroponically at 20/16 °C, 24/20 °C, 28/24 °C, and 32/28 °C, day/night air temperatures to evaluate effects on pod and seed yield, flowering, harvest index, and oil content. Ten-day-old peanut seedlings were transplanted into rectangular nutrient film technique troughs (0.15 × 0.15 × 1.2 m) and grown for 110 days. Growth chamber conditions were as follows: photosynthetic photon flux (PPF) mean of 436 μmol·m-2·s-1, 12 h light/12 h dark cycle, and 70% ± 5% relative humidity. The nutrient solution used was a modified half-Hoagland with pH and electrical conductivity maintained between 6.5 to 6.7, and 1000 to 1300 μS·cm-1, respectively, and was replenished weekly. Vegetative growth (foliage, stem growth, total leaf area, and leaf number) was substantially greater at increasingly warmer temperatures. Reproductive growth was significantly influenced by temperature. Flowering was extremely sensitive to temperature as the process was delayed or severely restricted at 20/16 °C. The number of gynophores decreased with temperature and was virtually nonexistent at the lowest temperature. Pod yield increased with temperatures up to 28/24 °C but declined by 15% at the highest temperature (32/28 °C). Seed yield, maturity, and harvest index were highest at 28/24 °C. Oil content (percent crude fat) increased an average of 23% and was highest at the warmest temperature (32/28 °C). These results clearly suggest that vegetative and reproductive growth, as well as oil content of peanut in controlled environments, are best at warmer temperatures of 28/24 °C to 32/28 °C than at cooler temperatures of 20/16 °C to 24/20 °C.

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randomized complete block design. Data collection consisted of measuring the growth index (GI) for each treatment in the fall of each year (1999–2001). The GI was determined as follows: where, h is the height of plants (in centimeters), and w1 and w

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, full canopy with no dieback). Growth index. Growth index (GI) was used as a quantitative indicator of plant growth. Growth index for each plant was calculated as: GI (m 3 ) = H × W1 × W2, in which H is the plant height (m), W1 is the widest width of the

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® ; Ortho Co., Marysville, OH, USA) was sprayed onto stems and leaves of all plants on 29 Apr 2020 for a minor mealybug infestation. Variables evaluated A growth index (GI) was calculated from the growth parameters of height, length, and width [GI

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shoot base to the apex. These data were used to calculate growth index [size = (height + width 1 + width 2 )/3]. After 16 weeks of production, plants were prepared for destructive sampling by removing growing media from roots, and by physical

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by total number of cuttings harvested. A plant growth index was calculated for each stock plant using plant height and width [(mean plant width + plant height)/2] to evaluate the combined effects of changes in height and width and to monitor overall

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. Table 1. Trade names, application rate, and active ingredient of the biostimulant products tested in Expts. 1 (zinnia) and 2 (petunia). Plant growth and performance assessments for Expt. 1 included plant growth index (GI), SPAD index, shoot and

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recorded at planting (0), 4, 8, 12, 20, 28, 52, 64, 76, 88, and 104 WAP to calculate canopy growth index [GI (m 3 ) = H × W1 × W2]. Maximum root spread and root to canopy spread ratio. Maximum root spread was measured at 12, 20, 28, 52, 64, 76, and

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, monthly until 52 WAP, and every 3 months until 100 WAP. Size index (SI) was used as a quantitative indicator of plant growth. Size index was calculated as follows: SI (cubic meters) = H × W1 × W2, where H is the plant height (meters), W1 is the widest

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