Effect of organic cultivation technology on row crop yielding capacity

. The study aimed to estimate the effect of organic technologies on yielding capacity of row crops in the North-West Russia and the after-effect of compost on the successor crop. Experiments took place in 2020-2022. The crop rotation included the zoned perennial grasses, potato, and table beet. Potatoes were fertilised with BIAGUM compost produced from poultry manure in a fermenter. In 2020-2021, the compost application doses were 0 (control), 4 and 8 t ha -1 (5.5 t ha -1 in 2022) or 0 (control), 80 and 160 kg N ha -1 (110 kg N ha -1 in 2022). The table beet was sown on the plots fertilised in the previous year under potatoes. The mechanical weed control of row spacing was performed twice in the growing season. Weather conditions were monitored by the own weather station near the experimental field. The year 2021 was the warmest and the driest in the study period. In 2022, the rainfall was satisfactory for crops – 238.20 mm. In control variants, the potato yields ranged from 12.78 to 20.25 t ha -1 that was 25.6-67.5% of the cultivated variety potential. Application of 4 t ha -1 of compost only slight affected the yield. But with higher compost application dose, a significant yield gain (greatest 56.88%) was observed, especially under favourable climatic conditions of 2020. The biggest beetroot average yield – from 22.5 to 27.7 t ha -1 – was also in 2020. In 2022, the average yield was from 21.5 to 24.3 t ha -1 . By the study results, the applied organic technologies proved effective for producing potatoes and table beet in the North-West Russia.


Introduction
Russia, as well as today's world in general, features a growing demand for cleaner agricultural products [1].In this regard, more and more small and medium-sized farms are switching to organic technologies, in crop growing as well [2][3].
Organic technologies include the operations of basic and pre-planting/sowing tillage, planting, and crop care.They avoid or largely exclude application of synthetic fertilisers, pesticides, and plant growth regulators.Introduction of organic technologies promotes the use of crop rotations, green manures, organic fertilisers (composts), and novel biological pest and disease control agents.They also stipulate designing new mechanical tools for weed control.These measures use the natural environment to enhance agricultural productivity [13].
To get organic products, the crop cultivation should comply with several norms and requirements prescribed in special documents.The main one is Federal Law No. 280 "On Organic Products and on Amendments to Certain Legislative Acts of the Russian Federation" of 3 August 2018.The state interest in increasing the quantity and quality of organic products is supported by the "Strategy for Development of Organic Production in the Russian Federation until 2030" approved by the Prime Minister of the Russian Federation in July 2023.
Crop cultivation by organic technologies, however, is associated with some risks of worsening the environmental and sanitary parameters of agroecosystems.This is due to the bans to apply chemical plant protection agents, the spread of weeds, and insufficient amount of organic fertilisers allowed for use in organic technologies.It is believed that at the first transition stages to organic crop production, the yields can be up to 30% lower compared to conventional technologies [4].
In this regard, sectoral research institutes face the task of creating new plant protection biological agents and growth stimulators, approved for use in organic farming systems [5].The role of crop cultivation technologies in the sustainable development of organic production is also worth mentioning [6].To achieve the greatest plant productivity with specified quality requires the creation of new crop cultivation technologies.They need to be adaptive to specific soil and climatic conditions.Their main task is to prepare the physical state of soil for normal growth and development of cultivated crops [7][8][9].
Positive results have already been achieved in the organic production of grain, fruit, and berry crops [10,11].The adaptation of row crops cultivation technologies to the requirements of organic production poses some unresolved problems yet.The study aimed to estimate the effect of organic technologies on the yields of row crops -potato and table beet -in the North-West Russia and the after-effect of compost on the successor crop.

Materials and methods
Field investigations took place on the experimental fields of the Institute for Engineering and Environmental Problems in Agricultural Production (IEEP) -branch of FSAC VIM, south of Saint Petersburg, in a six-field crop rotation.The row crops, adapted for the conditions of the North-West region of the Russian Federation -potato and table beet -were grown on sod-podzolic soil on carbonate loam.The potato was a domestic variety "Udacha" with a commercial yield of 30-50 t ha -1 .The potato predecessor was perennial grasses cultivated for seed.The successor of potato was the table beet of the mid-season Dvusemennaya TSHA variety.This root crop is round-shaped with red pulp, weak corking of the head, and weakly expressed rings.Generally, its commercial yield is 40.4-54.7 t ha -1 .
In 2020 and 2021 the compost application doses under potato were 0 (control), 4 and 8 t ha -1 .In terms of the active substance, nitrogen (N), they were 0 (control), 80 and 160 kg ha - 1 , respectively.According to the experiment plan, in 2022 5.5 t ha -1 of compost, or 110 kg N ha -1 , were applied under potato instead of 8 t ha -1 .The table beet was not fertilized directly.Table beet seeds were sown on the plots fertilized with compost before planting potatoes in the previous year.
The row spacing on both potato and table beet plantations in all experiment variants was 70 cm.Each variant had five replications.The obtained experimental data were analysed in Microsoft Excel and Statistica software packages.
In the experimental studies, the own weather station was installed in the immediate vicinity of the experimental field.It performed the continuous automatic monitoring of the E3S Web of Conferences 462, 02006 (2023) AFE-2023 https://doi.org/10.1051/e3sconf/202346202006climatic parameters providing the real location data, rather than the average data from urban weather stations.Figure 1 and Figure 2 show the results of weather data analysis.According to precipitation analysis during the study period, the most optimal amount was 564.55 mm in 2020, with the required one for potato normal growth and development being 300-400 mm, and that for the table beet in the conditions of the North-West region being 350 mm.The data from the own weather station showed that the year 2021 was not only the warmest one in terms of average temperature, but also the driest one.In the period of crop productive mass increment, the amount of precipitation was critical and averaged 16 mm.A   3 present the technologies of potato and table beet cultivation that were used during the experimental studies.

Fig. 3. Technologies of potato and table beet cultivation
The soil preparation for growing potatoes started in autumn.The off-bottom plowing incorporated the perennial grass (predecessor).Then, the pre-sowing tillage prepared the soil for winter rye sowing.This crop covered the surface with the green mass to prevent the water and wind erosion in autumn and to reduce the soil moisture evaporation in spring.
The spring field work started with pre-planting soil preparation by a cultivator for the overall tillage, which incorporated the green mass of winter rye.Then, the application and incorporation of the organic fertiliser took place simultaneously with ridging.
The organic fertiliser was poultry manure-based BIAGUM compost [9].After the fertilisation, the potato planting went along with simultaneous treatment of seed material with biological preparations in the planter coulter through the installed nozzles.
During the plant growth and development, two inter-row treatments were performed with rotary harrows for weed control and hilling up potatoes.To prevent the diseases, potato plantings were sprayed with special biopreparations approved for use in organic farming.No field treatments followed the potato harvesting.
The spring stage of the table beet cultivation started with pre-sowing tillage with a rotary cultivator for soil structuring.Then the ridges were cut, and the seeds were sown in the profiled field surface.Two inter-row treatments with a rotary harrow during the growing season maintained a loose topsoil in the inter-row spacing and controlled the weeds.After the beetroot harvesting, the field was prepared for perennial grass sowing.According to Table 1, in prevailing climatic conditions of 2020-2022, the organic technology under study with no organic fertilizers applied, yielded from 12.78 to 20.25 t ha - 1 that is 25.6 to 67.5% of the potential of cultivated Udacha potato variety.Application of organic fertilizer obtained from poultry manure, processed in a fermenter, contributed to significant yield gains.In 2020, under the favourable weather conditions, the biggest yield increase was 56.88%.Even in the dry conditions of 2021, the potato succeeded to uptake nutrients, and the yield increase at the biggest application dose was 28%.

Results
Table 2 presents the results of experimental studies on the effect of organic cultivation technology on the table beet yielding capacity.When the table beet was sown on plots where BIAGUM compost had been applied under potato in the previous year, the after-effect of the fertiliser was observed next year.The year 2020 demonstrated the biggest average yield of table beet in the experiment -from 22.5 to 27.7 t ha -1 depending on the compost doses applied under potato in the previous year.Under unfavourable climatic conditions in 2021, the table beet yields decreased significantly.Average yield values ranged from 7.92 to 9.83 t ha -1 .In 2022, the average table beet yields ranged from 21.5 to 24.3 t ha -1 that was lower than the values of 2020.The average yield increase in plots with the biggest compost application dose for 2020 and 2022 was 8.39-13.02%.relative to the control variant, and in 2021 at low yields this difference was 24.

Discussion
Climatic conditions of cultivated crop vegetation periods in 2020-2022 differed greatly in terms of average temperature and precipitation.During the study period, the year 2020 turned out to be the best by these indicators.The amount of rainfall during the most important months of plant development in 2020 had a significant impact on yield performance.The year 2021 was the driest during the study period.The average temperatures by months of vegetation differed by 2-5 C°.The precipitation in June-July was critical, which dramatically affected the yield.The year 2022 was more stable with respect to 2021 in terms of precipitation distribution and average temperatures.
The results of organic technologies use in the row crops cultivation proved the possibility to achieve the yields comparable with the average ones in the country.The average potato yield in Russia in 2022 was 25.30 t ha -1 , and in the presented experimental studies the biggest yield was 31.77t ha -1 .The average yield in the experiments for three years was 20.59 t ha -1 .
The results for table beet yields are also close to the average yields on private farms in Russia.In 2022, the average table beet yield was 32.70 t ha -1 , while during the experimental studies the maximum yield was 24.30 t ha -1 .
The difference in yields is explained by the fact that the beetroot was not fertilized directly.The effect of yield increase in the experiments was achieved owing to the aftereffect of BIAGUM compost produced from fermented poultry manure and applied to potatoes a year earlier.The average yield of table beet for three years was 19.62 t ha -1 .

Conclusion
By the study results the applied organic technology proved effective for producing potatoes and table beetroot in the conditions of the North-West region of the Russian Federation.The study also confirmed the after-effect of BIAGUM compost obtained by fermenting the chicken manure in a closed installation on the yield of the successor crop in the crop rotation.

Fig. 1 .
Fig. 1.Average temperatures by month in 2020-2022 The analysis of average temperatures by month during the vegetation of cultivated crops demonstrated the highest temperatures prevailing in 2021.This greatly affected the yield.The temperature difference in the months of crop productive mass increment was 10-20% compared to the years 2020 and 2022.

Table 1
presents the results of experimental studies on the effect of organic cultivation technology on potato yielding capacity.

Table 2 ,
under the favourable weather conditions, the technological operations under study contributed to fulfilling the potential of the cultivated table beet variety within 50.1-67.8%.