Evaluation of some ecophysiological factors for sustainable management of wild Gladiolus (Gladiolus segetum)

Nowadays, regarding better integrated weed management and its control, attention to weed biology is critical and should be accepted as a scientific activity in weed science society (Rashed Mohassel et al., 2001). Precise weed biology identification will lead to better management practices (Alebrahim etal., 2009; Pahlevani etal., 2007). To be successful, weed management programs based on weed ecology and biology, need to acquire the correct information about environmental factors such as temperature, humidity, and their effects on plant characteristics (Zand etal., 2007). In weed science, non-chemical weed management by physical methods is one of the best usable methods. The purpose of this study was to evaluate Gladiolus weed biology to develop techniques for sustainable management.
This research was done in the Faculty of Agriculture and Natural Resources laboratories at the University of Mohaghegh Ardabili. Treatments included: 1- Evaluating the effect of different temperatures (5, 10, 15, 20, 25, 30, 35 and 40 degrees centigrade) on the emergence of Gladiolus corms in a completely randomized design with 4 replications. 2- Evaluating the effect of different temperatures and drying periods on the emergence of wild Gladiolus corms as a factorial in a completely randomized design with 4 replications. The first factor was storage periods in an oven for 4 different periods (1, 2, 3 and 4 weeks). The second factor was oven temperature at 5 levels (20, 23, 25, 35 and 40 degrees centigrade). 3- Evaluating the effects of different temperatures and freezing periods on the emergence of wild Gladiolus corms as a factorial in a completely randomized design with 4 replications. The first factor was storage periods in an incubator for 4 different periods (1, 2, 3 and 4 weeks) and the second factor was freezing temperatures at 6 levels (0, -5, -10, -15, -20 and -25 degrees centigrade).
Results showed that among different temperature treatments, the corms emerged at 15-30ºC. The higher emergence percentage was 87.5% at 20ºC. By increasing water reduction in corms in the oven, emergence ability was reduced. Further, with a 36/25 percent water reduction in corms, emergence ability reached zero. Corm emergence ability was affected by temperature and oven storage length. The highest survival rates with 100% emergence was with a temperature between 20 -25ºC after being stored for 1-2 weeks in the oven. Results also showed that by increasing the freezing period and lowering the temperature, the survival of wild Gladiolus corms was reduced. Further, at temperatures of -15, -20 and -25ºC the emergence ability reached zero. The highest emergence rate was at 0 ºC with a 1 week freezing period.
In this experiment 20ºC, was the optimum temperature for emergence of corms. Generally, by putting corms in temperatures higher than 30ºC or lower than -10ºC, the emergence ability reached zero. Thus with no chemical treatment and just by using environmental conditions in cold and warm climates, this weed density will be reduced and sustainable management will be achieved.