Effect of Nitrogen and Vermicompost Interaction on Growth and Development of Kinnow Mandarin in Vertisols of Jhalawar District Pawan

Among citrus fruits, mandarin (Citrus reticulata Blanco) is placed at first with respect to area and production followed by sweet oranges and limes. Kinnow (Citrus nobilis × Citrus deliciosa) is a hybrid between „King‟ and „Willow leaf‟ mandarin. It is extensively cultivated in Punjab and Sri Ganganagar districts of Rajasthan. Kinnow plant has vigorous and drooping growth habit and produces heavy yield under favourable growing conditions. It has attractive fruit colour, size and good eating quality. Its fruits are nutritious, juicy and have bright and deep colour. The fruit is a rich source of minerals and also contains carotene and vitamin C. Kinnow fruit production is intended for fresh fruit market. The total production of oranges in India is 3255.0 thousand tonnes from an area of 324.0 thousand hectares with the productivity of 10.0 MT/ha [1]. In Rajasthan, Kinnow mandarin covers 17.62 thousand hectares area with a total production of 1.46 lac MT/ha [2]. However, Jhalawar district is blessed with Nagpur mandarin where it is grown over 22,500 ha area, 13,000 ha of which are in the fruit bearing stage and the production is 2 lac tonnes [3]. In India, the average yield of citrus is about 10 t/ha, which is quiet less than the citrus yield (20-25 t/ha) in other countries like Brazil, Spain, USA, Japan, China and Mexico. The low productivity is probably due to nutritional imbalance, poor orchard management and general negligence of citrus orchard [4]. Nitrogen is considered as the most important component for supporting plant growth. While nitrogen is a natural element, plants cannot absorb it in this natural form. The nitrogen in the environment is synthesized into fertilizers which are readily available to plants. A proper application of balanced fertilizer promotes thick, green and sustainable orchard. Nitrogen is an essential constituent of protein and chlorophyll and is present in many other compounds of great physiological importance in plant metabolism, such as nucleotides, phosphatides, alkaloids, enzymes, hormones, vitamins, etc [5]. Vermicompost increase the efficiency of chemical fertilizers, it works on the principle of maintenance and improvement of soil fertility for sustainable productivity on term basis. The importance and usefulness of organic manure in soil sustainability has been emphasized and judicious use of inorganic fertilizer along with organic sources has been suggested. The use of organic fertilizers with inorganic fertilizers as a supplement to maintain balance in nutrients and to regulate cropping in farming practices [6]. Keeping in view of all these facts, integration of inorganic fertilizers particularly nitrogen in combination with vermicompost may be helpful for increasing the growth and development of Kinnow mandarin at pre bearing stage. Better growth and development at pre bearing stage of fruit Abstract A field experiment entitled “Effect of nitrogen and vermin compost interaction on growth and development of kinnow mandarin in vertisols of Jhalawar district” was conducted at the Fruit Research Farm, Department of Fruit Science, College of Horticulture and Forestry, Jhalawar (Rajasthan) during 2012-13 to study the effect of different levels of nitrogen and vermicompost on growth and development of Kinnow mandarin. The experiment consisted of 16 treatment combinations having four levels of nitrogen i.e. 0, 0.115, 0.230, 0.350 kg/plant and four levels of vermicompost i.e. 0, 10, 15, 20 kg per plant and it was laid out in factorial randomized block design with four replications. The experimental plants were 4 years old and at vegetative growth phage. The result indicate that application of T15 treatment i.e. nitrogen @ 350 g/plant + vermin compost 20 kg/plant was found best with regards plant growth parameters i.e. East-West and NorthSouth plant spread, plant height, canopy volume, shoot height, shoot diameter, relative water content and number of leaves/shoot.