Introduction: Pinto beans are weak and sensitive to weeds and the presence of weeds drastically reduces its yield, so weed control is one of the most important issues in planting this crop. Weeds compete with crops for moisture, nutrients, light, and space, and are considered barriers to production in cropping systems. Therefore, this experiment was performed to obtain the best planting date and the best management method to increase the yield of the pinto beans.
Materials and methods: This factorial experiment was performed based on a randomized complete block design with three replications in the field of Gonbad Kavous University Faculty of Agriculture in the spring of 2018-19. The first factor included three planting dates: 03/25/2019, 04/06/2019, and 04/06/2019. The second factor: weed management in four levels, consisted of treflan as pre-planting at the rate of 2.5 liters per hectare, treflan + once weeding, double weeding, haloxyphoparamethyl at the rate of one liter per hectare + bentazon at the rate of 2.5 liters per hectare. Also in this study, weed-free and weed-infested plots were considered as controls. At the end of the growing season, by removing marginal effects, 10 pinto beans were selected from each plot and the number of pods per plant, number of seeds per pod, 100 seeds weight and dry weight per plant, biological yield, and harvest index, seed weight per square meter and final yield were measured. Prior to statistical analysis, the data were normalized in Minitab software. Then, the data was statistically analyzed by SAS software. Mean data were compared by LSD test.
Results: The results showed that the number of pods per plant on the first planting date was 5.44 which was significantly different from the second planting date (4.60). Also, the highest number of seeds per pod, biological yield, harvest index, seed weight, and final yield on the first planting date were obtained from double weeding and treflan treatment while the lowest were obtained from without weeding. However, on the second planting date, the highest results of the mentioned traits were obtained from the weeding and treflan treatment, whereas the lowest results were obtained from the non-weeding treatment.
Conclusion: The results of the present study showed that when the average air temperature during the bean flowering period reached 27.7 ° C it disrupted the inoculation process and led to the lack of seed production and economic yield in pinto beans, so it is recommended that not to delay planting date of the pinto beans in Gonbad Kavous area from mid-April and of course in the present experiment from the date of the second planting (04/06/2019). The highest yield of pinto beans was obtained from the date of first planting and the management method of double weeding and treflan. The results of this experiment, which was performed on the natural flora of weeds, showed that in successful weed control, it was important to know the history and type of weeds in the field. Herbicides will be effective if the weeds in the field match the limited control range of the herbicides. |
