The aims of these studies were to evaluate the growth variability (growth experiment) and the response to cultivated rice competition (competition experiment) of 10 weedy rice populations selected in Italian rice fields on the basis of their phenotypic features. The experiments were carried out under field conditions in 15-L pots with 6 replications by seeding 1 weedy rice plant/pot in growth experiment, and 1 weedy rice plant surrounded by 10 cultivated rice plants/pot in competition experiment. Plant height, tiller and leaf numbers were recorded 6 times through the growing season for both studies. In the competition study, leaf area, tiller and leaf weight were also assessed.In the growth experiment a variable behaviour was shown by the different weedy rice populations for all the growth parameters. The culm numbers was the most homogeneous parameter among the populations, while leaf weight was the most variable. In the competition experiment, curve fitting between each growth parameter and time after seeding showed different behaviour with and without rice competition. Weedy rice in competition always showed lower growth indices than when grown alone. Plant height was the parameter less affected by competition, showing an average of 16% reduction compared to non- competition. Leaf and culm weight were heavily affected by competition with an average of 68% and 65% reduction, respectively. Two awnless populations showed an opposite growth behaviour, being the most and the least affected by rice competition with a 30% difference in growth reduction averaging among all parameters. Italian weedy rice populations, with phenotypic variability, responded diversely in terms of plant height, leaf and culm production, in either presence or absence of rice.
Growth variability of Italian weedy rice populations grown with or without cultivated rice
ANDRES, ANDRE;FOGLIATTO, SILVIA;VIDOTTO, Francesco;FERRERO, Aldo
2012-01-01
Abstract
The aims of these studies were to evaluate the growth variability (growth experiment) and the response to cultivated rice competition (competition experiment) of 10 weedy rice populations selected in Italian rice fields on the basis of their phenotypic features. The experiments were carried out under field conditions in 15-L pots with 6 replications by seeding 1 weedy rice plant/pot in growth experiment, and 1 weedy rice plant surrounded by 10 cultivated rice plants/pot in competition experiment. Plant height, tiller and leaf numbers were recorded 6 times through the growing season for both studies. In the competition study, leaf area, tiller and leaf weight were also assessed.In the growth experiment a variable behaviour was shown by the different weedy rice populations for all the growth parameters. The culm numbers was the most homogeneous parameter among the populations, while leaf weight was the most variable. In the competition experiment, curve fitting between each growth parameter and time after seeding showed different behaviour with and without rice competition. Weedy rice in competition always showed lower growth indices than when grown alone. Plant height was the parameter less affected by competition, showing an average of 16% reduction compared to non- competition. Leaf and culm weight were heavily affected by competition with an average of 68% and 65% reduction, respectively. Two awnless populations showed an opposite growth behaviour, being the most and the least affected by rice competition with a 30% difference in growth reduction averaging among all parameters. Italian weedy rice populations, with phenotypic variability, responded diversely in terms of plant height, leaf and culm production, in either presence or absence of rice.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
