Influence of sowing date on seed yield and quality in onion (Allium cepa L.) by production 'seed to seed' method

Abstract

The experiments took into account four cultivars origin from different agroclimacteric regions, usually grown in our country (Prizrenski pogačar, Kupusinski jabučar, Trebinjska kapula and Holandski žuti), are The sowings were realized on 15 July (first term), 5 August (second) and 25th August (third). Sowings were carried out in rows 45cm apart and 5cm apart along the row (number of plants 44,8/m2). Experiment was split-plot designed with three replicaties. Gibberellic acid-GA3 sprays were applied with concentration at 50ppm on plants at the 6-7 leaves stage. Yield and its principal components were analyzed (percentage of flowering, capsules/umbel, seed/capsule, 1000 seed weight, germination energy, germination). Flowering percentage in the two years was affected by sowing date. Sowing postponement from July to August caused a reduction in the flowered plant from 90% to 40%, which produced only one umbel per plant. Sowing-flowering-seed ripening was reached almost simultaneously after 405-370 days. Seed production was highest in the first term sowing from 15 July for all cultivars. The cultivars showed differences in both years. Cultivar Kupusinski jabučar obtained the highest yield in the first term sowing - 440,4 kg/ha (in first year), while Holandski žuti obtained significantly lower in the third term from 25 August with only 140,6kg/ha (in first year).

U istraživanjima su zastupljene četiri sorte crnog luka poreklom iz različitih agroklimatskih područja u našoj zemlji (Prizrenski pogačar, Kupusinski jabučar, Trebinjska kapula i Holandski žuti). Setva je obavljena 15 jula (I rok setve), 5- avgusta (II) i25. avgusta(III). Setva je vršena u redove na rastojanju od 45cm i pri rastojanju u redu od 5cm (sklop biljaka 44,8/m2). Ogled je postavljen po split-plot metodu u tri ponavljanja. Giberelinaska kiselina GA3 je primenjena u koncentraciji od 50 ppm kada su biljke u fazi 6-7 listova. Analiziran je prinos i glavne komponente prinosa (procenat cvetalih biljaka, plodova/cvasti, semena /plodu, masa 1000 semena, energija klijanja, ukupna klijavost). Procenat cvetanja u toku dvogodišnjeg istraživanja uslovljen je vremenom setve. Odlaganjem setve od jula ka avgustu rezultira redukcijom procenta cvetalih biljaka od 90% -40%, uz produkciju samo jednog cvetonosnog stabla po biljci. Setva-cvetanje-sazrevanje semena prispeva skoro istovremeno nakon 405-370 dana. Najveća proizvodnja semena je ostvarena u i setvenom roku od 15-Jula kod svih sorata. Sorta razlika je prisutna u obe godine proizvodnje. Najveći prinos ostvaren je kod sorte Kupusinski jabučar u I roku setve-440,4 kg/ha (u prvoj godini) i značajno niži u III roku od 25. avgusta kod Holandskog žutog sa svega 140,6 kg/ha (u I godini). .