Relative Humidity Influences Yield, Edible Biomass, and Linear Growth Rate of Sweetpotato

Abstract

<jats:p>Growth chamber experiments were conducted to study the physiological and growth response of sweetpotato <jats:italic>[Ipomoea batatas</jats:italic> (L.) Lam.] to either 50% or 85 % relative humidity (RH). Vine cuttings of T1-155 were grown using the nutrient film technique in a randomized complete-block design with two replications. Temperature regimes of 28/22C were maintained during the light/dark periods with irradiance at canopy level of 600 μmol·m<jats:sup>-2</jats:sup>·s<jats:sup>-1</jats:sup> and a 14/10-hour photoperiod. High RH (85%) increased the number of storage roots per plant and significantly increased storage root fresh and dry weight, but produced lower foliage fresh and dry weight than plants grown at 50% RH. Edible biomass index and linear growth rate (in grams per square meter per day) were significantly higher for plants grown at 85 % than at 50% RH. Leaf photosynthesis and stomatal conductance were higher for plants at 85 % than at 50% RH. Thus, the principal effect of high RH on sweetpotato growth was the production of higher storage root yield, edible biomass, growth rate, and increased photosynthetic and stomatal activity.</jats:p>

Crop Physiology of Sweetpotato

“…The response curve of PN/I depends upon the leaf internal CO 2 concentrations (G i ) and an increase in inter-cellular CO 2 concentrations causes the P N rate to saturate at a high level ofl (Kubota et al 1992b). High relative humidity (RH) increases P N rate and plants grown under higher RH (850/0) have greater stomatal conductance and P N rates than those grown under low RH (Mortley et al 1994). Photosynthesis of sweetpotato leaves is also influenced by stomatal resistance (SR) because SR regulates C i (Kubota et al 1994).…”

Effect of carriers on physicochemical properties, antioxidant activities and biological components of spray-dried purple sweet potato flours

“…The anthocyanins of purple sweet potatoes not only show great potential in terms of natural colorants but also provide various nutraceutical properties such as freeradical scavenging activity (Oki et al, 2002). Storage of fresh sweet potatoes requires nicely controlled temperature (13e15 C) (Reesa et al, 2003) and relative humidity (85e95%) (Mortleyl, Bonsi, Loretan, Hill, & Morris, 1994;Padda & Picha, 2008), which could be fulfilled with advanced and expensive equipments. It is also manpower consuming.…”

High Relative Humidity Increases Yield, Harvest Index, Flowering, and Gynophore Growth of Hydroponically Grown Peanut Plants

“…Ball, Batavia, Ill.) media in TLC transplant flats (TLC Polyform, Plymouth, Several studies have documented the positive effects of relative humidity (RH) on growth of plants, including lettuce (Lactuca sativa L.) (Tibbitts and Bottenburg, 1976), wheat (Triticum aestivum L.), sugarbeet (Beta vulgaris L.) and kale (Brassica oleracea L.) (Ford and Thorne, 1973), red kidney bean (Phaseolus vulgaris L.) (O'Leary and Knecht, 1970), pearl millet (Pennisetum typhoides S.) (Black and Squire, 1979), potato (Solanum tuberosum L.) (Wheeler et al, 1989), and sweetpotato [Ipomoea batatas (L.) Lam.] (Mortley et al, 1994). However, there are few studies on the effects of RH on growth and yield of peanut.…”