Eggplant: improvement of agricultural techniques

The results of the influence of drip irrigation regimes and organic mineral fertilizers on the productivity of eggplant when grown in the dry-steppe zone of the Tersko-Sulak lowland of the Republic of Dagestan are presented. The purpose of the research is to develop methods of agricultural techniques for eggplant cultivation, which ensure that the planned yield of at least 60 t/ha of high-quality fruits is obtained at the level of pre-irrigation soil moisture in the range of 80–100% WC and the calculated irrigation regime. The object of research is the medium-early variety of eggplant Almaz. A two-factor field experiment was conducted in 2013–2015 on zonal meadow-chestnut medium-loamy soils of JSC Educational and Experimental Farm (Kirovsky district of the Republic of Dagestan). The soils of the experimental site were characterized by a low humus content – 1.9%, an average supply of easily hydrolyzed nitrogen – 49 mg/kg of soil, a low supply of mobile phosphorus – 15 mg/kg and an average supply of exchangeable potassium – 207 mg/kg of soil. Agrophysical indicators of the fertility of the irrigated soil: the volume mass of the root layer – 1.25 t/m3, the lowest moisture capacity – 17.9%. As organic fertilizers, semi-rotted manure was used, from mineral fertilizers – ammonium nitrate and urea, double superphosphate and potassium chloride. All analyses, records and observations were carried out in accordance with generally accepted methods. It was found that the increase in the lower threshold of soil moisture and the use of fertilizers contribute to an increase in the efficiency of irrigation water use by 2.5 times, an increase in photosynthetic activity, and, in particular, an increase in the efficiency of headlights up to 1.2%. The best combination of crop-forming factors is to maintain the lower moisture threshold of the root layer of the soil during the growing season at least 80 and 90% WC against the background of 40 t/ha of manure + N320P120K210. During the growing season of eggplant, 24–66 waterings (depending on weather conditions and humidity threshold) with irrigation rates of 146 and 73 m3/ha, respectively, and the introduction of 40 t/ha of manure and half the rate of mineral fertilizers with three nitrogen fertilizations, provides the highest fruit yield – 62.3–63.6 t/ha.

Key words: eggplant, drip irrigation, fertilizer rates, irrigation regime, yield