Effect of manure on growth and yield of broccoli

ABSTRACT

Continuous use of synthetic fertilizers affects soil structure. Nitrates accumulate in broccoli (Brassica oleracea var. italica Plenc) and can have detrimental health effects in humans. Nitrate levels increase with the use of synthetic fertilizers compared with animal manures. Manures can serve as an alternative to synthetic fertilizers. The study evaluated performance of cow or sheep manure, or chicken litter, on growth and yield of broccoli, cvs. Balimo, Green majic, and Zone. The number of leaves and branches, plant weight, time to 50% emergence of heads, broccoli head weight and diameter, contents of protein and sulfur in heads, and total yield were determined. The cv. Balimo treated with sheep manure produced more leaves/plant (~61). Plants treated with chicken litter had the widest heads (22 cm) and highest protein content (32.2%). The chicken litter produced more sulfur in heads than cow manure and sheep manure was intermediate. Chicken litter produced a higher yield than sheep manure, and cow manure produced a yield that was intermediate. The cv. Balimo had heavier plants than did “Zone,” and those of “Green majic” were intermediate. The cv. Zone had the most branches/plant (~12), heaviest heads (589.16 g), least time to 50% heading (~81 days), and most total yield (23.57 t.ha⁻¹). The cv. Zone had wider heads than ‘Green majic’ and those of cv. Balimo were intermediate. The cv. Balimo had highest head protein content (32.2%). Chicken litter can be used to improve vegetative growth, and yield quality and quantity, and the broccoli cv. Zone appears to be the best of the cultivars tested.

KEYWORDS:

• Brassica oleracea var. italica
• cultivars
• fertilizer
• organic materials
• yield quality