Germination Ecology of Ivy-Leaved Morning-Glory: an Invasive Weed in Soybean Fields, Iran

Abstract

Ivy-leaved morning-glory (Ipomoea hederacea Jacq.) is an exotic species that is becoming an increasing problem in soybean fields of Golestan province, Iran. Because little information is available on the biology of this weed species in Iran, experiments were conducted to investigate the effects of different factors on seed germination and emergence of Ivy-leaved morning-glory. Maximum germination occurred at constant temperature of 20 oC (82%) and alternating temperature of 15/25 oC (94%). Germination was reduced with increasing salinity and drought stresses. Sodium chloride concentration and osmotic potential that inhibited 50% maximum germination were -1.64 and -1.03 MPa, respectively. Acidity was a limiting factor for the germination, due to inhibiting effect of alkaline conditions on germination. However, the results showed that high temperature pretreatment >100 oC decreased seed germination. Germination decreased from 82 to 3% as temperature increased from 100 to 130 oC. There was no significant difference between seedling emergence in burial depths of 1 to 10 cm, but emergence reduced with increasing burial depth from 10 to 14 cm, and no seedling was emerged from a depth of 15 cm. The results of the flooding experiment also revealed that the seeds of this species are sensitive to this stress, so that emergence was 9% after 3 d flooding.

Salt and Water Stress Tolerance in Ipomoea purpurea and Ipomoea tricolor, Two Ornamentals with Invasive Potential

“…Additionally, in agreement with the results shown here, high germination percentages under salt stress conditions were found in this species [65,66], as in others of this genus [67,68]. A comparative study on several environmental constraints in I. purpurea revealed that germination was more affected by temperature than by salinity and seedling emergence by flooding and burial depths of over 13 cm [69]. The two species analysed here had similar germination patterns and percentages, except germination at −0.88 MPa osmotic potential in I. purpurea, which was more affected by stress than I. tricolor.…”

Germination ecology and growth phenology of cowvine (Ipomoea lonchophylla) as influenced by environmental parameters

“…integriuscula A. Gray) (Gomes et al 1978; Siahmarguee et al 2020). We found a significant number of seeds (47%) emerged from the 8-cm burial depth, and we suggest that shallow burial of seeds through light tillage to reduce I. lonchophylla density may not significantly improve control of this species.…”

The effect of environmental factors on seed germination and emergence of cutleaf geranium

“…was severely reduced as a result of exposure to high temperatures. The maximum germination percentage of this species was halved at a temperature of 119 °C, and no germination was observed at temperatures higher than 130 °C (Siahmarguee et al, 2020). Sohrabi et al (2016) reported that the germination of Cucumis melo L. is inhibited when the seeds are subjected to long periods of heat at 90 °C.…”

“…There were three pots per treatment, and three bags were placed in each pot. The pots containing the seeds were placed inside larger plastic pots (20 cm diameter and 30 cm depth) to maintain 3 cm water above the soil (Siahmarguee et al, 2020). The bags were extracted from pots 0 (control), 2, 5, 10, 15, 20, and 30 days after burial.…”