Effect of sowing dates and planting density on the infestation of onion maggot (Delia alliaria fonseca) in onion (Allium cepa l.) crops
Year: 2015
Type: article
Abstract: Onion maggot (Delia alliaria Fonseca) is an important pest of onion in Iraq, it is responsible for causing serious quantitative and qualitative losses to the onion crops. Nursery and field studies were conducted at college of Agriculture, Abu Ghraib, Iraq to evaluate the effects of sowing date and plant density on onion infestation with onion maggot. Onion seeds were sowing in nursery at three dates viz 5th & 20th September and 3 rd October, 2010 with two plants density i.e. 10seed/2m2 and 15 seeds /2m2. From Nursery, the plants were transplanted to the field at three dates viz 14th & 24th December, 2010 and 3 rd January, 2011 with two density i.e. 10seed/2m2 and 15 seeds /2m2 with 10 cm and 6 cm plant spacing. Result of the study showed that the lowest infestation of onion maggot was manifested at the lower plants density and first date of cultivation at both nursery and field level. At nursery level 6.16, 6.83 and 7.50 % infestation was reported for three dates of showing respectively at 10g seeds / 2 m2 while this infestation was 8.61, 7.50 and 11.5 % respectively for the three sowing dates at 15 g/2 m2 densities. Similar types of results were reported in the field study but with slightly higher infestation, here 8.81, 12.54 and 14.04 % infestation was reported on the three plantings dates at 10 cm plant spacing respectively while this infestation was much higher 12.13, 16.81 and 19.04 % respectively for three sowing dates on the 6 cm plant spacing. Higher yield was obtained from the plants of the 1 st date of sowing for both the plant densities with best quality. The mean bulb weights were 252.90, 228.30 and 172.00g for the plants growing at 10 cm spacing while this weights was 213.5 , 167.0 and 153.7 g for the plants growing at 6 cm spacing for all the three dates of cultivation respectively. Results of the study revealed that cultivation onion at early date with suitable spaces between the plants may be promising to manage the infestation with onion maggot.
Author: Feryal B. Hermize
Language: English
Subfield: Insect Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W2013623338