Acta Agronomica Hungarica, 49(2), pp. 169–174 (2001) 0238–0161/2001/$ 5.00©2001 Akadémiai Kiadó, Budapest EFFECT OF DIFFERENT SOWING METHODS ON YIELD AND BULB CHARACTERISTICS IN ONION (ALLIUM CEPA L.) S. MASSIHA, A. MOTALLEBI and F. SHEKARI DEPARTMENT OF HORTICULTURAL SCIENCE, FACULTY OF AGRICULTURE, TABRIZ UNIVERSITY, TABRIZ, IRAN Received: 7 February, 2001; accepted: 16 May, 2001 Direct sowing (DS), row direct sowing (RDS), and the transplanting method (TM) were investigated for two onion cultivars, Azar-Shahr (red skin onion) and Horand (yellow-brown skin onion) during 1999, at Khalat-Pooshan Research Station, Tabriz University. Analysis of variance for the measured traits indicated that except for the percentage of class II onions, other traits were significantly influenced by the sowing methods. TM had higher values of total yield, marketable yield, percentage of class I and III, bulb weight, homogeneity (HOM) of bulb weight, bulb diameter, HOM of bulb diameter, bulb length, HOM of bulb length, bulb diameter at the neck and base, number of centres, and percentage of bulbs containing multiple centres than the other methods. The cultivars differed significantly only for bulb weight, HOM of bulb weight, and postharvest longevity characteristics. The data suggest that TM could be an effective method in onion production areas without causing a change in soil texture. RDS was also a better method than DS in terms of marketable yield, and homogeneity of bulb weight. Key words: Allium cepa L., onion, direct sowing (DS), row direct sowing (RDS), transplanting method (TM), bulb characteristics, marketable yield Introduction The transplanting method (TM) is more common than direct sowing (DS) in onion production and research in developed countries (Dobrzanski, 1973; Orkwor et al., 1981; Comrie, 1986. Ahmed et al., 1990; Brewster, 1990; Muro et al., 1991. Dobrzanski et al., 1995; Singh and Tiwari, 1995; Gupta et al., 1996; Sinha et al., 1996; Daymond and Wheeler, 1997). TM has a beneficial effect on onion production in five important ways: it provides better establishment of seedlings, earliness, homogeneous bulbs and higher yield than DS and also prevents a change in soil structure. In trials with the onion cvs. Yellow Bermuda and Granex the highest yields resulted from TM and the lowest from DS (Ramtohul and Splittstoesser, 1979). Pessala (1990) carried out experiments at 2 sites in Southern Finland in 1987 and 1988 and concluded that DS gives lower class I (>5 cm in bulb diameter) yield (2–3 t/ha) than TM (35–40 t/ha). Huerres-Perez (1978) reported that onions transplanted in early December gave the highest total yield in both years (1976–1977) in Cuba. Warid and Loaiza (1993) indicated that DS gave a lower overall average yield than TM (36.2 t/ha for DS vs. 44.1 t/ha for TM) in Mexico. Torres et al. (1986) showed that with TM the yield was 20.37–35.86 t/ha and with DS it was 10.35–10.38 t/ha in the State of Santa Catarina, Brazil. Khokhar et al. (1990) obtained data on bulb maturity, bulb weight and yield either directly in the field or in the nursery followed by transplanting at 3 dates