Vegetative Growth and Yield Potential of Cauliflower (Brassica oleraceae var. botrytis, L.) Plants as Affected by Inorganic and Organic Nitrogen Fertilization

Document Type : Original Article

Authors

1 Vegetable Crops Dept., Fac. Agriculture, Alexandria Univ., Egypt.

2 Fertilization Technology Dept., National Research Centre, Dokki, Cairo, Egypt.

Abstract

Two field experiments were conducted at the Experimental Station Farm, Faculty of Agriculture, Alexandria University in two successive winter seasons of 2006/2007 and 2007/2008 to follow up the influences of different levels of inorganic N (0, 40, 80 and 120 kg N fad.-1 as NH4NO3) and organic N (0, 5, 10 and 15 m3 fad.-1 as chicken manure), as well as their collaborative effects on cauliflower vegetative growth characters and chemical composition of leaves. In addition, determine both maximum (total and marketable yields), and minimum (non-marketable one) of cauliflower "Amshiry" cultivar were considered.
The results showed that the application of medium and high levels of inorganic N fertilizer (80 and 120 kg N fad.-1) increased significantly most of the vegetative growth characters such as plant fresh weight, plant height, leaves number, leaves and stem dry matter content, and stem diameter. Increasing significant values for both total and marketable yield of cauliflower were, also, recorded for the same two levels. On the other hand, the non-marketable yield reflected pronounced decrease as a result of application the same two levels. Significant increases of macro- and micro-nutrient concentrations in leaves of cauliflower were obtained by raising N levels.
Application of chicken manure rates up to 15 m3 fad.-1 revealed significant increases in vegetative growth parameters, concentrations of macro- and micro-nutrient in leaves, and yield characters during both seasons.
The best treatment combination appeared to be that of the highest levels of inorganic and organic N fertilizers (120 kg N/fed.-1 as NH4NO3 + 15 m3; i.e., 72 kg N/fed.-1 of chicken manure) followed by (80 kg N/fed.-1, NH4NO3 + 15 m3, chicken manure). Application of the last treatment gave maximum marketable yield as well as total yield, and at the same time lowered non-marketable yield of cauliflower. It can be concluded that the use of chicken manure can decrease the used quantity of inorganic N fertilizer and, consequently, improves the economics of cauliflower production as well as reduces the unfavorable effects on the environment under the study region conditions.

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