Effect of growth regulator and microfertilizer on potato yield in Yakutia

Abstract

The results of studying the effect of growth regulator Novosil and microfertilizer Mag-Bor on growth parameters, photosynthetic activity of plants and yield of potato variety Yakutyanka in conditions of Central Yakutia are presented. The soil of the experimental plot is permafrost floodplain loamy with insufficient content of humus (1.8–2.2%), mobile compounds of magnesium (1.25 mg/100 g), molybdenum microelements (0.03 mg/kg), manganese (29.0 mg/kg), and boron (0.30 mg/kg) in the arable layer. It was found that treatment of potato plantings with Novosil increased plant mass by 19–24%, leaf area and photosynthetic potential by 5–7%, with magnesium-boron fertilizer (at a dose of 5 g/l) by 9 and 2%, respectively. Significant direct relationship of plant weight with its height and number in a bush (r = 0.71. 0.81), leaf area and photosynthetic potential values – with height, number and weight of plants (r = 0.56. 0.82) was revealed. The contribution of the preparations to the variability of indicators was 37–68%, weather conditions and factor interactions – 3–33%. It was demonstrated that treatment of plants with Novosil and together with Mag-Bor 5 g/l increases tuber yield in comparison with the control by 6.4–6.6 t/ha (34–35%), and with magnesium-boron fertilizer at a dose of 5 g/l – by 2.5 t/ha (14%). In the variants Mag-Bor 10 g/l and Novosil + Mag-Bor 10 g/l the yield was at the level of control or increased by 1.6 t/ha (8.5%), and under drought conditions it decreased by 0.5–0.9 t/ha. The share of the preparations' influence on the yield variability amounted to 68%, weather conditions – 26%, and factor interactions – 4%. Regression equations were calculated, allowing to forecast leaf area and tuber yield by plant weight in the flowering phase promptly and with high accuracy. The difference between the actual and the calculated values was 4.4–5.4%.