Weeds as Alternate Organic Fertilizer in Garlic (Allium sativum L.) Production

The use of synthetic fertilizers for garlic production is hazardous, hence utilizing weeds as a source of organic fertilizers is a novel and organic approach to improve yield and quality of garlic. This research aimed to determine the potential of major weeds as a source of fertilizers and their effect on garlic growth. Garlic cloves were planted in pots (4 kg soil) in completely randomized design. The treatments were five different weeds applied at 25 and 50 g kg soil⁻¹ and compared with diammonium phosphate and farmyard manure. Results showed the higher and lower values of 13.75 (9.1% increase) and 10.75 (16.3% decrease) days to 50% germination was recorded in M. coromandelianum and C. arvensis used at 50 g kg⁻¹ soil, respectively. Maximum plant height of 70.12 cm (0.48% increase) was noted in P. hysterophorus and minimum height of 55.62 cm (25.47% decrease) in C. arvensis, maximum bulb weight (22.29 g, 0.19% increase) was recorded in X. strumarium and the minimum bulb weight (14.39 g) was recorded in C. arvensis. The maximum bulb diameter (39.47 mm) and fresh weight (23.49 g: 12.13% decrease) were found in control and farmyard manure. Meanwhile, minimum bulb diameter (30.72 mm: 28.48% decrease) in C. arvensis at 50 g kg⁻¹ soil, fresh weight (16.71 g: 40.63% decrease) was recorded in Parthenium (50 g kg soil⁻¹). In addition, the maximum yield (13.37 tons ha⁻¹) was noted in the X. strumarium used (50 g kg soil⁻¹), while least garlic yield (8.63 tons ha⁻¹) was recorded in C. arvensis (50 g kg⁻¹ soil). The overall data showed that X. strumarium could be a good source of organic fertilizers in garlic while C. arvensis negatively affected the garlic growth probably due to allelopathic effects.