http://localhost:8080/handle/123456789/3660 2026-04-11T18:45:21Z http://localhost:8080/handle/123456789/3680 POTASSIUM- THE QUALITY ELEMENT IN ENHANCING PRODUCTIVITY AND ALLEVIATING DETRIMENTAL EFFECT OF ABIOTIC STRESS IN PLANTS ZANNAT, MOSAMMAT SALMA ABSTRACT Potassium fertilizer management is beneficial for improving growth, yield and yield components of field crops under moisture stress condition. Three field experiments were conducted at the research farm of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the rabi season of 2016-2018 to evaluate the effects of potassium fertilizer enhancing the productivity and alleviating detrimental effect of abiotic stress along with other recommended fertilizer on the growth, yield, nutrient management, shelf life of the plant product and soil chemical properties, the research was conducted based on selected wheat (BARI gom26), rice (BARI dhan28) and carrot (New Kuroda) variety. The experiments were laid out in Split Plot Design and RCBD method with three replications. The first experiment was conducted on wheat in rabi season with sixteen treatment combination (4 levels of irrigation X 4 levels of K doses) viz. I 0 = control (normal irrigations), I = Water stress at vegetative stage, I 2 = Water stress at flower initiation stage, I 3 = Water stress at milking stages and K = 0 kg K/ha, K 1 = 60 kg K//ha, K 2 = 90 kg K/ha, K = 120 kg K/ha. Growth and yield contributing characters mainly plant height, number of spikelet’s, thousand grains weight of wheat crop were significantly influenced by the potassium fertilizer and water stress at different growth stages. The highest grain yield of wheat (4.04 t/ha) was observed under 120 kg K/ha from I 0 K 3 3 treatment combination, while the lowest grain yield (2.29 t/ha) was recorded from I 0 K 1 and I 0 K treatment combinations respectively. Among the combined effect of water stress conditions and different doses of potassium I 2 0 K combination provided the best result. The second experiment was conducted on rice in rabi season with eleven treatments including control viz. T 3 = Control (no fertilizer), T 2 = Fertilizer recommended dose for BRRI dhan28. (FRD) N 120 P 18 K 75 S 13 Zn 1.5 , T 3 1 = 25% K supplement by cowdung (1.25 t/ha) + 75% K (56.25 kg /ha K) from MoP, T = 25% K supplement by poultry liter (2.20 t/ha) + 75% K (56.25 kg/ha K) from MoP, T 5 4 = 25% K supplement by vermicompost (1.87 t/ha) + 75% K (56.25 kg/ha K) from MoP, T 6 = 50% K supplement by cowdung (2.50 t/ha) + 50% K (37.5 kg/ha K) from MoP, T = 50% K supplement by poultry liter (4.40 t/ha) + 50% K (37.5 kg/ha K) from MoP, T = 50% K supplement by vermicompost (3.75 t/ha) + 50% K (37.5 kg/ha K) from MoP, T 9 8 = 75% K supplement by cowdung (3.75 t/ha) 1 0 7+ 25% K (18.75 kg/ha K) from MoP, T = 75% K supplement by poultry liter (6.60 t/ha) + 25% K (18.75 kg/ha K) from MoP, T 11 10 = 75% K supplement by vermicompost (5.62 t/ha) + 25% K (18.75 kg/ha K) from MoP. The study in aspect of growth and yield contributing characters mainly plant height, effective tillers/hill, panicle length, filled grain/panicle, thousand grain weight, and harvest index and grain yield of boro rice. The maximum grain yield of rice (6.55 t ha -1 ) was produced from T treatment which was significantly different from the T 1 treatment (2.35 t ha -1 8 ). The third experiment was conducted on carrot with eight treatments including control viz. T 1 = 0 kg K/ha, T 2 = 20 kg K/ha, T 3 = 40 kg K/ha, T 4 = 60 kg K/ha, T = 100 kg K/ha, T 7 = 120 kg K/ha, T = 140 kg K/ha. Storage quality of carrot indicated that after seven days the lowest moisture reduction percentage was observed in K 8 (20.39%) while the highest moisture reduction percentage was found in K 0 (61.45%) followed by K 1 5 (60.24%). After 14 and 21 days same trend of moisture reduction were found. In room temperature, K treatment provided the best result and enhanced the shelf life of carrot. So, it can be suggested that the improvement of K- nutritional status of plants might be of great importance for the survival of crop plants under environmental stress conditions and potassium fertilizer with other recommended fertilizers would be ideal for better crop growth, increasing yield and shelf life of crops. 5 5 = 80 kg K/ha, T 6 A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN SOIL SCIENCE SEMESTER: JANUARY - JUNE, 2019 2019-06-01T00:00:00Z http://localhost:8080/handle/123456789/3661 EFFECTS OF INDUSTRIAL POLLUTION AND ARSENIC CONTAMINATION ON YIELD AND METAL ACCUMULATION IN RICE GRAIN AND SOIL BEGUM, MOST. NASRIN Heavy metal accumulation in rice grain appears to be a perilous problem because of application of chemical fertilizers, irrigation with arsenic (As) contaminated groundwater and use of industrial effluents. The present study was done to assess the yield and metal accumulation in Boro (BRRI dhan 28) and T. Aman (BRRI dhan 33) rice grown in industrially polluted and arsenic (As) contaminated soils. Treatments of the first pot culture experiment were T 0 (100% RDCF) and T 2 - N 75 P 15 K 30 S 10 – Control treatment; T 1 Zn 1.5 ii - N 150 P 30 (50% RDCF) + 6 ton cowdung ha ) in industrially polluted soils (S 1 – Non-polluted soil, S 2 – Polluted soil-1 and S 3 – Polluted soil-2). For the second pot experiment, different levels of irrigation (I 1 – Traditional irrigation and I 2 – Alternate wetting drying) were added along with fertilizes and manure doses (T 0 – Control; T 1 - N 150 P 30 K 60 S 20 Zn 3.0 K 60 S 20 (100% RDCF); and T 2 - N 150 P 60 K 60 S 20 Zn 3.0 ; T 3 –(N 75 P 15 K 30 S 10 Zn 1.5 (50% RDCF)+ 6 ton cowdung ha - N 75 P 15 K 30 S 10 Zn 1.5 (50% RDCF)+ 5-ton compost/ha) were considered as treatments for As-contaminated soils. Both the pot experiments were carried out in the net-house during December 2015 to November 2016. The experiments were laid out in a 2- factor Randomized Complete Block Design (RCBD) with three replications. Results indicated that heavy metal accumulation and yield reduction were more prominent in both types of contaminated soils compared to non-contaminated (control) soils. In contaminated soils, the minimum yield of Boro and T. Aman rice were observed in T 0 S 3 and the maximum yield was in T 2 S 1 followed by T 1 S 1 treatment. However, the maximum value of Cd, Pb and Zn accumulation in the grains of both Boro and T. Aman rice was found in the T 1 S 3 treatment, while the lower values were noted in T 0 treatment. Elevated levels of heavy metals such as Zn, Cd, Pb, Cr and Ni were found in soils receiving T 1 S 3 treatment. In case of As contaminated soils, the minimum yield for both Boro and T. Aman rice was obtained in T 0 I 2 followed by T 1 , and the maximum yield was in T 4 I 1 followed by T 3 I 1 treatment. Higher accumulation of Cd and Zn in both Boro and T. Aman rice, As in Boro rice, and Pb in T. Aman rice grains were recorded in the treatment T 2 I 2 I 2 , while the lowest values were noted in T 0 treatment. The higher and lower values of the heavy metals were recorded in T 4 and T 0 I 2 treatments, respectively. In addition to pot experiments, a field survey was done in Gazipur Sadar upazila to investigate the effect of toxic heavy metals and the contaminated wastewater on the livelihood and food safety of the people living adjacent to industrial areas. The survey results revealed that industrial effluent contamination remarkably affected rice production and further it caused deterioration of grain quality leading to low market price. Nevertheless, industrial effluents are directly or indirectly causing several socioeconomic, health and environment-related problems. A Thesis Submitted to the Faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka, in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN SOIL SCIENCE 2019-01-01T00:00:00Z