Growth of Sugar Beets as Affected by Root Temperatures Part I: Greenhouse Studies¹

Abstract

Sugar beets (Beta vulgaris var. saccharifera) were grown in the greenhouse at 10 different constant root temperatures. The temperature intervals were maintained at 2.8 C between 12.8 and 37.8 C. Optimum root temperature for sugar beet emergence occurred in the range of 25–35 C. The optimum root temperature for dry matter production in sugar beet tops progressively decreased from 26.3 C at 6 weeks following emergence to 23C at 13 weeks following emergence. Optimum temperatures for sugar beet roots remained between 24 and 25 C for the 7‐week period. Percent sucrose in the sugar beet roots increased with root temperatures above 19 C. High sucrose yields were obtained between 18 and 32 C, with rapid decreases outside of this range. Concentrations of N, P, K, and Na in the sugar beet tops and roots were not dependent on root temperatures; thus, the total uptake of these nutrients was directly proportional to dry matter accumulation in the plant.

Modeling Sugar Beet Responses to Irrigation with AquaCrop for Optimizing Water Allocation

“…Another important change was the modification of the base and upper temperature (Table 2) for better simulation of the crop development and the impact of low temperatures on stomatal conductance [29]. Our proposed changes are in line with those recommended by Reference [37] for the base temperature and by References [38] and [39] for the upper temperature. Although the default crop water stress parameters (Table 2) satisfactorily simulated the crop response under deficit irrigation (Figure 1b-d, Figures 2b-d and 3), a small change in the parameter that adjust HIo for water stress during yield formation (Table 2) allowed the correct simulation of the increase in HI due to the water stress suffered during the leaf expansion, as observed by Reference [40].…”

Infection of sugar beet by Polymyxa betae in relation to soil temperature

“…Cystosori were found in less than 8% of lateral roots per sample during the 28 days of the experiment and their density was always considerably less than in plants grown at 15 C. Reduced fungal development at this high temperature could be due. in part at least, to the effect of temperature on plant growth, the optimum for sugar beet being 23 25 C (Radke & Bauer, 1969). Changes in root metabolism and exudation associated with these above optimum temperatures could affect cyst germination, zoospore attraction or encystment.…”

Temperature Variation Within and Between Rooting Media in Plant Growth Chambers1

“…Cohen and Tadmor (1969) observed that root elongation of grass and legume seedlings increased with increasing temperature from 10 to 20C, but varied among species from 20 to 25C. Radke and Bauer (1969) reported that optimum root temperature for dry matter accumulation by sugar beet (Beta saccharifera) roots was 24 to 25C while percent sucrose increased with increasing root temperatures from 19 to 32C.…”