Growth and productivity of winter pea under different weed control practices in the Right Bank Forest Steppe of Ukraine
Authors: Kukuruza O. Ye. , Remeniuk S. O. 
Published: May 2024

Purpose. To analyze the features of growth and formation of the winter pea productivity under various weed control options in the Right Bank Forest Steppe of Ukraine.
Methods. The research was conducted at the Salyvonky State Enterprise of the Institute of Bioenergy Crops and Sugar Beet of the National Academy of Agrarian Sciences of Ukraine (Bila Tserkva district, Kyiv region) in 2020–2023. The agronomic practices used in the experiment were conventional for the zone of insufficient moisture of the Right Bank Forest Steppe of Ukraine, with the exception of the studied elements.
Results. The best conditions for the growth and development of pea plants and leaf area formation were noted for the autumn application of the herbicide Corum in the BBCH 12 stage. This contributed to the fact that during the flowering period, the leaf area of the crop plants was more than 36 thousand m2/ha, and in the spring, it was more than 35 thousand m2/ha. The use of the same herbicide in the BBCH  14 ensured the formation of a leaf area of more than 35 thousand m2/ha, which corresponded to the indicators of the treatment with herbicide Pulsar 40 in the BBCH 12. That is, winter pea crops, during flowering, are able to effectively limit the sprouting of new weed plants and the growth and development of their existing plants, which was facilitated by the timely application of the herbicide. The application of the herbicide Corum turned out to be the best option from the point of view of the formation of a high level of photosynthetic potential (PP) of pea crops. For the application in the herbicide in autumn in the BBCH  12 stage at an application rate of 1.50 l/ha, the FP was 1.57 thousand m2/ha × day. At the same time, application rate of 1.25 l/ha slightly differed from the best in the experiment. The spring application of the herbicide Corum in the BBCH  12 at application rates of 1.25 and 1.50 l/ha contributed to obtaining PP of 1.51–1.52 thousand m2/ha × days, which also provided the highest indicators in the spring block of the experiment. Since, thanks to the application of Corum herbicide, winter pea plants formed a large leaf area, the indicators of net photosynthesis productivity of crops in the best treatments were at the level of 2.89 g/m2 per day for autumn application and 2.64 g/m2 per day for spring application. The highest PP of pea in the experiment was provided by the use of herbicide Pulsar Flex, which was probably achieved due to the slightly smaller leaf area formed by the crops and the mild effect of the herbicide on the plants, which reduced the risk of stress in crops and contributed to active plant growth and development.
Conclusions. Autumn application of Corum herbicide to protect crops was the most efficient for increasing pea yield. In all years of research, as well as on average in the experiment, the application of 1.50 l/ha of this herbicide in the BBCH 12 provided the highest yield: 3.08, 1.98, and 3.68 t/ha in 2021, 2022, and 2023, respectively, and 2.91 t/ha on average over three years. In the second place in terms of yield formation efficiency was the application of the same rate of herbicide in the BBCH 14, while later application dates did not contribute to a high level of realization of the crop biological potential. Spring application of Corum was also effective at both application rates in the BBCH 12 stage of weed development: the yield of pea seeds was 2.52 and 2.62 t/ha, respectively.