Study on Some Ecological Aspects of Cutleaf groundcherry (Physalis angulata L.) Seed Germination and Dormancy

A better understanding of the factors influencing the germination of weed seeds could facilitate the development of more effective cultural weed management practices. The aim of this research was to determine the effects of environmental factors on seed germination of Cutleaf groundcherry (Physalis angulata L.). Results showed that application of gibberellic acid (GA3) was effective treatment for seeds primary dormancy breaking. Physalis angulata seed had identical germination in either light/dark or continuous dark regimes، indicating this weed species is non-photoblastic. However، the maximum germination percentages and germination rates were observed at warmer alternating temperatures. The ranges of response to the constant temperature for germination were widened during afterripening periods. Based on the 2-piece segmented model، the base، the optimum and maximum temperatures for germination of P. angulata were estimated to be 8. 06، 35. 83 and 42. 30 ˚C، respectively. The response thresholds of P. angulata to inhibit 50% of maximum germination for salinity and osmotic potential were 59. 25 mM and -0. 29 MPa، respectively. According to the weibull hydrotime model، hydrotime constant and base water potential to initiate germination were obtained equal to 26 MPa h and -1. 45 MPa، respectively.