Responses of onion growth and yield to different planting dates and land management practices

Received: September 10th, 2021 ; Accepted: November 3rd, 2021 ; Published: November 15th, 2021 ; Correspondence: h.salari@yahoo.comLocal varieties of onion (Allium cepa L.) are believed to be well adopted to agroecological conditions of their respective growing region but their lower productivity is a concern to be addressed. The variety ‘Safid e Paisaye’ was selected for this investigation due to its long storability and higher market demand. The present study was carried out at Agriculture Research Farm of Kabul University to study the influence of land management practices and planting dates on growth and yield of onion. Different agronomic traits including number of leaves per plant, leaf length, leaf area per plant, leaf area index, normalized difference vegetation index (NDVI), maturity period, marketable yield and total yield were studied in these trials. The recorded data were statistically analysed with R software. The planting dates had significant influence on growth and yield of onions. At 90 days after sowing, the highest number of leaves per plant (7.18), leaf length (30.07 cm), leaf area per plant (277.43 cm2 ), leaf area index (0.93) and NDVI (0.29) were recorded for the first planting date (10th May). Similarly, the longest maturity period (176.44 days) and highest marketable yield (37.01 t ha-1 ) and total yield (40.08 t ha-1 ) were also observed under the first planting date. Land management practices did not have significant effect on growth and maturity period of onions. However, the marketable yield was influenced by tillage depth and land preparation. The deep tillage and flatbed recorded highest marketable yield of 38.58 t ha-1 and 26.9 t ha-1 , respectively. The results of the study indicate that, early planting was more appropriate to get vigorous and high yielding onions. The deep ploughed flatbeds were appropriate to get higher marketable yield of onions