Thulasi, VInduja, MKAU2021-04-152021-04-152020174968https://krishikosh.egranth.ac.in/handle/1/5810163503MScThe present study entitled “Pilot testing of fertilizer-manure blocks in Okra (Abelmoschus esculentus L. Moench.)” was undertaken at Regional Agricultural Research Station Pattambi. The objective was to develop fertilizer-manure blocks for okra (organic matrix based compacted slow release fertilizer). The study include two experiments, laboratory incubation study and a pot culture experiment. The laboratory incubation study was conducted to select the best proportion of organic materials for developing fertilizer-manure block based on the nutrient release pattern. Pot culture experiment was conducted to identify the best package of application of the fertilizer-manure block. In the experiment-I fertilizer manure blocks were developed by mixing organic materials such as coir pith, cow dung, vermicompost, neem cake, ground nut cake, humic acid and zeolite powder in five different proportions along with per plant recommended dose of nutrients calculated based on KAU-POP recommendations. The five different proportions were as fixed based on the shape retention and consistency of the product. The fertilizer manure blocks in five different proportions (treatments T1-T5) and sole fertilizers (T6) were incubated in soil up to 60 days. Destructive soil sampling was done and analyzed for available N, P, K, Ca, Mg, Zn, Cu, and B and nutrient release kinetics during the incubation period was studied. The results of the incubation study revealed that, fertilizer-manure blocks made of all five proportions (treatments T1-T5) showed slow release pattern with respect to various nutrients as compared to sole fertilizer placement. Fertilizer-manure block made with proportion-1 (T1) had released 65 per cent of applied N, 54 per cent Ca, 47 per cent S at 60 days of incubation, while almost 100 percent of applied K and Mg was released within these days. In the case of micro nutrients Zn and Cu had released 12 per cent and 32 per cent of their contents respectively, whereas almost 100 percent born was released within 60 days of incubation. When compared among the different fertilizer-manure blocks, treatment T1 (proportion-1) exhibited slow release behavior to a greater extent and synchronization with physiological need of the tested crop, low cost of production and hence, was selected for the conduct of the pot culture experiment. In pot culture study fertilizer- manure blocks were prepared in two dimensions (100 g and 25 g) using three dosage of fertilizers (100 per cent POP, 50 per cent POP, and 25 per cent POP). Okra variety Arka Anamika was used as the test crop. The experiment consisted of 11 treatments with 3 replications such as T1 : Blocks of size 100 g with nutrients as per 100per cent POP @ 1 block per grow bag, placed below the level of planting, T2 : Blocks of size 100 g with nutrients as per 50per cent POP @ 1 block per grow bag, placed below the level of planting, T3:Blocks of size 100 g with nutrients as per 25 per cent POP @ 1 block per grow bag, placed below the level of planting, T4 : Blocks of size 25 g with nutrients as per 100 per cent POP @ 4 blocks per grow bag, placed on 4 sides of the plant at soil surface, T5 : Blocks of size 25 g with nutrients as per 50 per cent POP @ 4 blocks per grow bag, placed on 4 sides of the plant at soil surface, T6 : Blocks of size 25 g with nutrients as per 25 per cent POP @ 4 blocks per grow bag, placed on 4 sides of the plant at soil surface, T7 : T3 + 50 per cent POP recommendation as top dressing, T8 : Nutrients as per general POP of KAU, T9 : Nutrients as per soil test based POP recommendation, T10 : Control( Organic manure as per POP of KAU ) and T11 : Absolute control. Fertilizer-manure blocks showed significant effect on growth and yield of okra. Days to flowering, number of fruits per plant, fruit yield per plant, length of fruits, girth of fruits, and number of seeds per fruit were significantly influenced by the treatments. Treatment T8 ( nutrients as per general POP recommendation) had recorded lowest value for days to flowering which was found to be on par with the treatments T2, T3, T5, T6, T7, and T9. Treatment T7 had recorded more number of fruits per plant (20.70), fruit yield per plant (457.9 g), fruit length (17.90 cm), fruit girth (6.326 cm) as well as number of seeds per fruit (58.67). Treatment T8 and T9 (soil test based recommendation) were found to be on par with treatment T7 with respect to fruit yield per plant. Taller plant and more number of leaves were recorded for the treatment T7 while the number of branches were on par with the treatments T8 and T9. Application of fertilizer manure blocks had shown significant influence on the available nutrient status of the post harvest soil (N, K, P, Ca, Mg, S, Zn, Cu, B ). Highest available nitrogen content was recorded in the treatment T1, T4 and T7 which was found to be on par with the treatments T2, T5 and T6. Lowest phosphorus content was recorded in the absolute control treatment. Highest available potassium content was recorded in the treatment T4 (395.64 kg ha -1) and it was on par with that in treatment T1 (386.57 kg ha-1). Highest available calcium content was recorded in the treatment T5 whereas highest available magnesium content was recorded in the treatments T7 (424.96 mg kg-1) which was found to be on par with the treatment T1(418.0). Highest sulphur content was recorded in the treatment T7 (18.01 mg kg-1). In the case of micro nutrients highest zinc, copper and boron content was recorded in the treatments T8, T9, and T7 respectively. Application of fertilizer-manure blocks showed significant influence on nutrient uptake by the crop. However, highest nitrogen uptake was recorded in the treatment T9 and lowest in T11. Highest phosphorus and potassium uptake was recorded in the treatment T7. The use of fertilizer-manure blocks made with Coirpith- 35%, Cowdung- 25%, Vermicompost-13%, Groundnut cake- 10%, Neem cake 10%, Zeolite- 2%, Humic acid- 5% in 100g size containing 25% of the recommended dose of nutrients placed 5cm below the level of planting and top dressing of 50% of KAU POP recommendation improved okra growth and yield in grow bags and saved 25% of the fertilizers in comparison with POP recommendation.EnglishThesis