The effect of time and depth of planting on obtaining the planned potato yields

Abstract

In 2014-2017 In the northern forest-steppe zone of the Chelyabinsk region The influence of planting dates and the depth of seed placement of potatoes on the size and quality of tubers was studied. During the study period, physical soil maturity in the first decade of May was observed twice in 2014 and 2017. The early planting of potatoes (May 5) was accompanied by an increase in the harmfulness of rhizoctoniosis (in the Rosara variety - by 22.8%, Kuzovok - by 63.7%) and the Colorado potato beetle (by 26 and 43%, respectively) compared with the May 12-15 planting. . The seedlings of the early variety of Rosara potato on May 30 in 2014 were damaged by frost (–1.0 ° C). From meteorological and phytosanitary positions, the optimum term for planting potatoes in this is the beginning of the second decade of May. Planting potatoes on May 12-15 with embedding of seed material to a depth of 5-6 cm ensured the formation of the planned yield of 40 t / ha with a planting scheme of 70x19 cm (Rosara - 41.4 t / ha, Kuzovok - 44.6 t / ha), and in the variety Kuzovok - additionally with the scheme 75x27 cm (38.3 t / ha). The planting of potatoes on May 25-29 provided a predetermined level of productivity (40 t / ha) of the Kuzovok variety in all variants of the experiment, and the Rosara variety in the variant of thickened planting. However, the starch content in Rosara tubers decreased by 1.60%, Kuzovok - by 1.26%, starch collection from 1 ha decreased by 0.60 and 0.37 t / ha, respectively, and the accumulation of nitrates in tubers increased by 25.8 and 52.5% compared with the optimal landing period. The advantage here was a deep embedment of seed tubers: an increase in the yield of the Rosara variety averaged 0.88 t / ha, Kuzovok - 1.23 t / ha. During the late planting period (June 5–12), there was a significant decrease in productivity (Rosara - by 3.49 t / ha, Kuzovok - by 5.18 t / ha) and the quality of potato tubers compared to planting from May 12-15. The starchy content of tubers decreased by 1.87 and 2.11%, the collection of starch from 1 ha to 1.10 and 1.45 t / ha, respectively, and the accumulation of nitrates increased 2.05 and 2.19 times. The planned yield of 40 t / ha was achieved only in the variety Kuzovok in thickened planting variants. At the same time, deep seeding of seed material increased the yield of the Rosara variety on average by 1.39 t / ha, and the Kuzovok variety - by 1.90 t / ha. Early landing (May 5) in 2014 and 2017. did not lead to an increase in potato productivity compared to planting in the second decade of May. At the same time, the yield decrease of the Rosara variety was 5.82 t / ha, Kuzovok - 2.75 t / ha. The planned yield of 40 t / ha was noted only in the variant of the thickened planting of the variety Kuzovok.