CULTIVATION OF LATE-SEASON POTATOES AFTER GREEN MANURE CROPS

Abstract

This study evaluates the growth, biomass, and seed productivity of autumn-sown green manure crops on saline-irrigated soils in Kashkadarya. Species tested include rapeseed, oilseed radish, peas, grey mustard, and their mixtures. Key parameters measured were plant height (75.8–312.2 cm), density (108.4–468.7 plants/m²), biomass (26.4–34.3 t/ha), and seed yield: rapeseed (20.2–23.5 c/ha), grey mustard (15.6–18.4 c/ha), oilseed radish (19.3–21.7 c/ha), and peas (23.8–25.4 c/ha). Use of green manure crops improved soil bulk density (1.24–1.30 g/cm³), water permeability (70.3–122.8 m³/ha), and fertility indicators: humus (1.16– 1.20%), nitrate nitrogen (11.58–31.48 mg/kg), phosphorus (29.72–41.3 mg/kg), and potassium (301.5–312.0 mg/kg). Weed infestation decreased by 7.2–13.8%, while earthworm burrows increased 3.2–5.9 times. Late-season potato varieties showed longer vegetation (3–10 days), taller plants (65.3–73.4 cm), more branches (3.7–4.6), and larger leaf area (56.7–70.9 thousand cm²/m²). Tubers yield ranged 31.2–37.9 t/ha, commercial yield 30.1–36.5 t/ha, with a multiplication coefficient of 6.2–8.4