Integrated nutrient management for arrow root (Maranta arundinacea L.) under partial shade

Abstract

A field experiment was conducted in the Instructional Farm, College of Agriculture, Vellayani from June 1999 to March 2000 to study the efficacy of conjoint use of varying levels of organic manure and fertilizers for yield improvement of arrow root under partial shade. The treatments included three levels each of FYM (10, 15 and 20 t ha"), Nand K (40,80 and 120 kg each of Nand K20 ha-I). A uniform dose of 50 kg P20S ha-I was applied to all the plots. The experiment was laid out in a 33 partially confounded RBD confounding MNKin replication I and M2NK in replication 11. Application of FYM had profound influence on growth characters like plant height, sucker number, leaf number and dry matter production. Nitrogen also exerted significant influence on growth characters like plant height, sucker number, leaf area index and dry matter production. The effect of K was significant on dry matter production at the harvest stage and 80 kg K20 ha-I was found sufficient for higher dry matter production. Number of rhizomes per plant at harvest showed an increasing trend with increasing levels of FYM. Girth of rhizome and weight of rhizome per plant were influenced by the combined application of FYM and fertilizers. Higher rhizome yields were realised at the medium levels of FYM (15 t ha-I), N (80 kg ha") and K (80 kg K20 ha-I). The combined application of 20 t FYM, 40 kg Nand 120 kg K20 ha-I or 20 t FYM and 80 kg each of Nand K20 ha-I produced higher yields closely followed by lOt FYM + 120 kg N +

80 kg K20 ha"l. FYM @ 15 t ha', N @ 80 kg ha"1 and K @ 80 kg K20 ha"1 produced higher utilization index. The highest starch content and the lowest crude fibre content of the rhizome were recorded by the highest level of K (120 kg K20 ha ") tried while the highest protein content was recorded by the highest level of FYM (20 t ha') and N (120 kg ha ") applied. Application of FYM @ .20 t ha"1 enhanced the uptake of N, P and K as well as the post-harvest soil nutrient status. For higher N uptake, application of 80 kg N ha"1 was found sufficient. Uptake of K as well as available K in the soil after the experiment showed an increasing trend with increasing levels of K application. The study indicated that combined application of lOt FYM, 120 kg N and 80 kg K20 hal along with 50 kg P205 ha"1 is most advantageous for arrow root intercropped in coconut garden which resulted in the highest net income and benefit-cost ratio in the laterite soils of Vellayani.