Influence of different sources of nutrients on growth, yield and quality of Khasi mandarin grown under mid hills of Arunachal Pradesh (India)

Abstract: A field trial was laid out on 11 year old Khasi mandarin trees with 12 different doses organic sources (20, 40, 60, 80 kg each of FYM, pig manure and poultry manure) and three different doses (200, 100, 100; 400, 200, 200; and 600, 400, 400 g NPK / tree ) of inorganic fertilizers to evaluate the effect of different nutrient sources on growth and yield performance of Khasi mandarin. Highest number of fruits per plant was recorded with 600, 400, 400 g NPK application. Plant height (6.96 m), crop canopy (5.7 x 5.6 m) and yield were also highest with full dose of NPK. However, stem diameter (86.8 cm) was highest with the application of 80 kg pig manure. The physico-chemical characteristics of fruits showed that peel weight (32.14 g) and thickness (4.2 mm) were more with full dose application of NPK, while segment weight (87.52 g) and fruit weight (120.4 g) were highest with 80 kg application of FYM. Inorganic fertilizers other than reducing TSS have profound effect on the increase in acidity which in turn reduced the TSS: acid ratio. It can be concluded that 80 kg FYM or 80 kg pig manure application would replenish the depleted nutrients on the khasi mandarin growing soils and maintain soil health.