Abstract:
Onion is an important cash crop produced by smallholder farmers in Amhara Region. The
productivity of the crop is however low which is among others associated with Poor soil
fertility management practice coupled with under optimum plant population. Moreover, farmers are complaining where the present recommended 10 cm intra row spacing produces large
sized bulbs, which are not preferred by consumers for home consumptions. Therefore, the
present study was initiated with the objective of investigating the effects of intra row- spacing
and nitrogen fertilizer rates on growth and yield of onion. The treatments consisted of four
levels of Nitrogen fertilizer rate (0, 41, 82, 123 kg ha-1 N) and three-intra row spacing (4, 7.
10 cm). The experiment was down in Randomized Complete Block Design (RCBD) in factorial arrangement with three replications. Date on Growth, yield and yield components of onion
were collected and subjected to ANOVA using SAS (version 9.0) software. Both the main effect as well as the interaction effect of intra row spacing and rates of nitrogen fertilizer significantly influenced almost all the tested growth and yield components of onion. The highest
significant plant height (60.53cm), leaves number per plant (14.10cm), leaves length
(60.90cm), day to maturity (115 days) and bulb weight (96.05 g) were recorded from onion
plants supplied with 82kg ha-1 N and 123 kg ha-1 N both combined with 10 cm of intra row
spacing. The highest marketable bulb yield (43.80 t/ha) was recorded from treatment combination of 82 kg ha-1 N and 4 cm of intra row spacing. Onion plants without nitrogen fertilizer
application and narrow intra row spacing were inferior in almost all growth and yield components. Based on the results of the present study, the combination of 82 kg ha-1 N and 4 cm
of intra row spacing can be recommended for economical production of onion in the study
area since it recorded the highest net benefit with acceptable marginal rate of return. Since
the results are limited to one season and location, it is advised to repeat the experiment in
different area and season for forceful recommendations.
Keywords: Bombay Red Variety, Koga Irrigation Scheme, Marketable and Total Bulb
Yield
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Table of contents
Contents Pages
THESIS APPPROVAL SHEET.......................................................................................................ii
DECLARATION ............................................................................................................................iii
ACKNOWLEDGEMENTS ............................................................................................................iv