Estimation of base temperature for Sorghum halepense rhizome sprouting

Abstract

Sorghum halepense is a rhizomatous perennial summer weed. It spreads by seeds and rhizomes that form ramets. The development of predictive models for ramet emergence (RE) from rhizomes may provide important information about their seasonal dynamics and consequently for the timing of control operations. The aim of this work was to analyse the effect of temperature on S. halepense rhizome sprouting (RS) and to estimate its base temperature, which is the first step for creating mathematical models to predict RE. Rhizomes collected from two North Italian populations were incubated at several constant temperatures. The total number of ramets, sprouted rhizomes and their ratio (ramet/sprouted rhizome) were calculated. The influence of temperature on sprouting performances was analysed. Base temperature was calculated using two methods: the reciprocal time of 50% RS (method) and RE (method). Confidence limits (at 0.95 level) were defined for each estimated base temperature using a bootstrap method. Base temperatures were compared to verify whether there were differences between populations and methods. Results indicated a significant stimulating effect of temperature on S. halepense rhizome performances. Estimated base temperatures did not differ between populations, nor between methods within a population (Padova RS 9.7 ± 1.25°C (confidence limits), RE 10.0 ± 1.28°C, Mantova RS 8.0 ± 1.89°C and RE 9.7 ± 1.23°C). The same thresholds may consequently be adopted for thermal time models for the two populations. These results also suggest that both methods (RE and RS) can be used without distinction to estimate the rhizome base temperature

Transcriptome analysis reveals plasticity in gene regulation due to environmental cues in Primula sikkimensis, a high altitude plant species

“…We observed a decline in rhizome sprouting of transplant individuals at the AA site (< 50% germination rate), whereas at A and BA sites rhizome sprouting was greater than 85%. The decreased in rhizome sprouting of P. sikkimensis at AA transplant site may be attributed to cold temperature, as the temperature is an important environmental variable regulating the sprouting of plant rhizomes [54]. Similar to our study, other studies also found the cold temperature to be an important factor in reducing and/or delaying the rhizome sprouting [54, 55].…”

“…The decreased in rhizome sprouting of P. sikkimensis at AA transplant site may be attributed to cold temperature, as the temperature is an important environmental variable regulating the sprouting of plant rhizomes [54]. Similar to our study, other studies also found the cold temperature to be an important factor in reducing and/or delaying the rhizome sprouting [54, 55]. For example, temperature range of 25–35 °C was optimum for the sprouting of turmeric ( Curcuma longa L.) rhizomes, and sprouting did not occur below 10 °C [56].…”

Base temperatures for germination of selected weed species in Iran

“…This approach, originally developed by Rochè et al (1997), has already been adopted to estimate t b for seed germination or rhizome sprouting (Masin et al 2010;Loddo et al 2012). A logistic function (Eq.…”

Estimation of biological parameters for germination of Abutilon theophrasti Medik.

“…Values of base temperature and water potential of the Croatian ecotypes of velvetleaf were then compared to the Italian ecotype, according to the criterion of 95% confidence intervals overlapping. If did not overlap, they were considered statistically different (P = 0.05), as already adopted in similar studies (25).…”