EFFECT OF CHEMICAL FERTILIZER AND ORGANIC MANURING ON CARROT PRODUCTION UNDER LITCHI BASED AGROFORESTRY SYSTEM

Abstract

A field experiment was conducted at the Agroforestry and Environment Research Farm, Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur, during December 2015 to March 2016 to evaluate the growth and yield performance of carrot cv. New kuroda influenced by the applications of different chemical fertilizer and organic manuring under litchi based agroforestry systems along with sole cropping i.e. open field condition. The experiment was laid out in two factors randomized complete block design (RCBD) with three replications. The treatments were factor A: Four chemical and organic fertilizer applications viz. F1 = Control (no fertilizer), F2 = Full chemical, F3 = Cowdung + Poultry and F4 = Cowdung. On the other hand factor B was Two Production system viz. S1 = Sole cropping of carrot and S2 = Carrot cultivation at the floor of Litchi orchard i.e. Litchi + carrot. So the treatment combinations were: F1 S1, F1 S2, F2 S1, F2 S2, F3S1, F3S2, F4S1 and F4S2. The main effect of chemical and organic fertilizer applications on growth, yield contributing characters and yield of carrot was found significant in response of plant height, number of leaves plant-1 , fresh leaves weight plant-1 , fresh root weight, dry root weight, root diameter and yield. The plant height was measured at 30, 45, 60 and 75 days after sowing (DAS) and the tallest plant height (34.37, 38.92, 42.21 and 44.54 cm) was found in the treatment where full chemical fertilizer was applied. On the other hand the shortest plant height (27.33, 30.57, 33.04 and 33.89 cm) were found in the treatment where no fertilizer was applied (control treatment). The highest carrot yield (11.86 t ha-1 ) was found in full chemical fertilizer application and the lowest carrot yield (6.93 t ha-1 ) was also found in no fertilizer treatment. Litchi based production system was sensational on growth and yield of carrot. The highest carrot yield (11.21 t ha-1 ) was found in sole cropping of carrot production system and the lowest carrot yield (7.89 t ha-1 ) was found in litchi + carrot based agroforestry production system. Significantly the highest root diameter (2.61 cm) was recorded in treatment combination of carrot sole cropping + full chemical fertilizer and the lowest root diameter (1.82 cm) was observed in treatment combination of carrot under litchi + no fertilizer. Similarly the highest carrot yield (13.14 t ha-1 ) was found in treatment combination of carrot sole cropping + full chemical fertilizer and the lowest carrot yield (5.60 t ha-1 ) was found in carrot cultivation under litchi tree + no fertilizer application treatment combination. Among the different chemical and organic fertilizer applications, full chemical fertilizer gave the highest yield at open condition as well as it performed well under litchi based agroforestry system. However, as compare to chemical fertilization, the organic manuring i.e. only cowdung application gave 15.07% yield reduction in case of open condition and 30.52% yield reduction in case of litchi + carrot based agroforestry production system. Again if we compare the yield reduction of cowdung + poultry manure as compare to chemical fertilization, then the yield reduction was 6.62% in case of sole cropping and 24.29% in case of litchi + carrot based agroforestry production system. So, in the context of chemical free safe carrot production with the benefit of environment as well as soil health then carrot may be cultivated using cowdung + poultry manure at the both floor of litchi orchard or sole cropping.