Зерновое хозяйство России (May 2018)
The effect of weediness by trailing bindweed (Convolvulus arvensis) on the elements of winter wheat productivity
Abstract
Trailing bindweed (Convolvulus arvensis) was the main weed on the fields sown with winter wheat variety ‘Povolzhskaya 86’. The article considers the effect of various degrees of weediness by trailing bindweed (sparsae, copiosae1, copiosae3) on the main elements of winter wheat productivity. The estimation of the weediness degree has been carried out by the Drude method. The largest losses of yields (15.0-28.0% depending on the year of study) occur with heavy weediness (copiosae3). All three degrees of weediness reduce the main elements of productivity. But the indexes of such elements of productivity as ‘number of kernels per head’ and ‘kernels weight per head’ have increased from 2.6% till 18.0%. Such increase has happened due to the increase of area of nutrition of one plant. The weediness had the largest negative effect on ‘number of productive stems’ and ‘dry tops’ (17.0-28.0%). The weediness by trailing bindweed had an effect on density of winter wheat, on formation of the elements of productivity. Trailing bindweed had a smaller effect on the elements of productivity in the year with optimal stand than in the year with spaced sowings (sparsae). The correlation coefficient for each year of study has been estimated. The dispersion analysis which shows true difference between the control and the variants of the experiment has been conducted. The largest decrease of the indexes occurred in 2014, as the sowings were spaced because of bad wintering; it resulted in weak competitiveness of winter wheat to weeds. Weak competitiveness of winter wheat to trailing bindweed had a negative effect of the main elements of productivity.