Abstract

Integrated nutrient management refers to maintenance of the soil fertility and plant nutrient supply to an optimum level for sustaining the desired crop productivity through optimization of the benefits from all possible sources of plant nutrient in an integrated manner. Therefore, it is a holistic approach, where we first know what exactly is required by the plant for an optimum level of production, in what different forms these nutrients should be applied in soil and at what different timings in the best possible method and how best these form should be integrated to obtain highest productive efficiency on the economically acceptable limits in an environment friendly manner. To identify suitable integration of different sources of nutrients in different ratios with respect to vegetative growth, fruit yield and quality, a field investigation was carried out on integrated nutrient management in acid lime (Citrus aurantifolia Swingle) in randomized block design with three replications. There were nine treatments, T₁- Control (500 : 300 : 300 g NPK per tree through fertilizers), T₂- 2/3 RDF + 1/3 through Goat manure, T₃- 2/3 RDF + 1/3 through Neem Cake, T₄- 1/3 RDF + 2/3 through Goat manure, T₅- 1/3 RDF + 2/3 through Neem Cake, T₆- 50% RDF + 50% through Goat manure, T₇- 50% RDF + 50% through Neem Cake, T₈- 100% RDF as Goat manure, T₉- 100% RDF as Neem Cake. The observation on growth parameters of acid lime tree, fruit yield and yield attributes and fruit quality were recorded to study the effect of treatments and their interpretation. Results of the investigation revealed that treatment T₆ (50% RDF + 50% through goat manure) performed best among all treatments. The maximum vegetative growth and yield (7.58 kg tree^-1) of fruits having highest fruit length (4.43 cm), fruit diameter (3.99 cm) and fruit weight (35.71 g) was recorded under T₆ treatment. Similarly best quality fruits were also produced with maximum juice (43.37%), TSS (10.42%) and Ascorbic acid (86.33 mg/100 g juice) content and minimum seed (1.15%) and acidity (6.06%) content under the same treatment.

Key words: Integrated nutrient management, acid lime, vegetative growth, fruit yield, fruit quality.