Farmer’s Field Evaluation of Above-and Below-ground Agronomic Attributes and Economic Indices of Different Onion (Allium cepa L.) Varieties in South-western Punjab

In south-western Punjab (India), several varieties of onion (Allium cepa L.) are cultivated with variable agronomic attributes which showed differential temporal response. The present study evaluated the temporal variation in above-and below ground agronomic attributes of six different onion varieties viz. hybrid Takii (T-821), Sardulewala selection, L-28, Red-4, Punjab Naroya and PRO-7 at farmer’s field during two consecutive years (rabi-2021 and 2022) to quantify their production potential and economic indices. These results revealed significant (p<0.05) differences in agronomic attributes among varieties; although there was large variation among two seasons. As compared with rabi-2021, considerable decrease occurred in plant attributes viz. number of leaves (4.8-15.9%), plant height (4.6-9.9%) and length of leaves (5.3-16.6%) during rabi-2022. Similarly, the equatorial diameter (DE) and polar diameter (DP) differ significantly among varieties, and score index elucidated T-821 as prolate (94% onions had score factor <1), while others were oblate (90-95% onions had score factor >1). There was a linear significant (p<0.05) relationship between DE vs. DP (R²=0.626-0.873*, p<0.05) and DE vs. fresh bulb weight (R²=0.735*, p<0.05). The fresh bulb yield of different varieties varied between 26.2 and 35.4 Mg ha-1 and 27.6 and 37.8 Mg ha-1, respectively during rabi-2021 and 2022. Fresh bulb yield of Red-4 variety was significantly lower (by ~24.9-27.0%), compared with PRO-7. Bulb yield was decreased by ~5.1-8.5% during rabi-2022, compared with rabi-2021. The highest gross returns (GRs), net returns (NRs) and benefit-cost (B-C ratio) were obtained for PRO-7 compared with other varieties.