Urea Supergranules Research Articles

Performance of separated tillers of transplant Aman rice at different levels of urea super granules

An experiment was conducted at the research field of Department of Agronomy, Bangladesh Agricultural University, Mymensingh during June to December 2012 to investigate the effect of age of tiller seedlings, number of tiller seedlings hill-1 and application of urea super granules (USG) on the yield and yield contributing characters of transplant Aman rice (cv. BRRI dhan52). The experiment consisted of two ages of tiller seedlings viz. 25 and 35-days old, three levels of tiller seedlings hill-1 viz. 1, 3 and 5 seedlings hill-1 and three levels of USG viz. 0, 1.8 (55 kg N ha-1) and 2.7g USG (80 kg N ha-1) four hill-1 in every alternate row. The experiment was laid out in a Randomized Complete Block Design (Factorial) with three replications. The highest plant height, number of effective tillers hill-1, number of total tillers hill-1, number of total spikelets panicle-1, number of grains panicle-1, grain yield and harvest index were found in 1.8 g USG applied @ one granule 4-hill-1. The highest number of sterile spikelets panicle-1 was found in control treatment and the lowest in 1.8 g USG. The highest number of effective tillers hill-1, number of total spikelets panicle-1 and grain yield ha-1 was found when 5 tiller seedlings were transplanted hill-1 combined with 1.8 g USG. Application of urea super granules 1.8 g (55 kg N ha-1) at 10 days after transplanting @ one granule 4-hill-1 in every alternate row with 25 day old tiller seedlings using 5 tiller seedlings hill-1 was found beneficial for grain yield of transplant Aman rice. Tiller separation could be an alternative source of seedling during seedling scarcity.Bangladesh J. Agril. Res. 40(4): 581-590, December 2015

Utilization of Urea Super Granule in Raised Bed Versus Prilled Urea in Conventional Flat Method for Transplanted Aman Rice (Oryza Sativa)

Bed planting with urea super granule (USG) application of rice production systems is very new and research on it is still at an introductory phase. Impact of granular urea application on growth and yield of transplanted aman rice as well as evaluation of water and fertilizer use efficiency of rice-fallow-rice cropping system was investigated under raised bed cultivation method. Result showed that the USG in bed planting method increased grain yield of transplanted aman rice up to 12.32% over prilled urea (PU) broadcasting in conventional method. The USG application in bed planting method increased the number of panicle m-2, number of grains panicle-1 and 1000-grains weight of rice than the PU in conventional method. Sterility percentage and weed infestation were lower at USG application in bed planting method than the PU in conventional method. Forty percent irrigation water and time for application could be saved through the USG in bed planting than the PU broadcasting in conventional method. Water use efficiency for grain and biomass production was higher by the USG application in bed planting than the PU broadcasting in conventional method. Likewise, agronomic efficiency of the USG in bed planting was higher than the PU broadcasting in conventional method. This study concluded that the USG in bed planting method is a new approach to get better fertilizer and water use efficiency as well as higher yield compared to the existing agronomic practice in the world.

Growth and Yield Performance of Tidal Local Aman Rice as Influenced by USG Application at Non Tidal Condition

An experiment was carried out at research field of Bangladesh Rice Research Institute, Gazipur to evaluate the performance of tidal local aman rice as influenced by urea super granule (USG) at non-tidal condition. Four tidal local aman varieties such as Sadamota, Razashail, Kutiagoni and Kalagura were used as planting materials. Nitrogen was applied as USG (1.8g) at 10 days after transplanting (DAT), 25 DAT, before panicle initiation (BPI) stage (date of PI stage of these 4 varieties were identified from previous experience) and no nitrogen (control). The experiment was laid out in a split-plot design where varieties in main plot and USG in sub-plot with three replications. Varietals response was significant on plant height, effective tillers hill-1, grains panicle-1 and grain yield. All the yield and yield components were influenced significantly by the time of USG application. Higher dry matter was produced by all the varieties when USG was applied at early growth stage (10 to 25 DAT) but crop lodges at milking stage due to more vegetative growth resulting increases sterility, decreases grain fertility and yield. On the other hand, when USG was applied at BPI stage grain fertility and yield were increased. The highest grain yield (3.51 t ha-1) was recorded from Kalagura when USG applied before panicle initiation stage. So, application of USG at BPI stage in local aman rice in non-tidal condition increased yield resulting higher gross and net return in all varieties.Bangladesh Agron. J. 2015, 18(1): 71-80

Evaluation of N Efficiency Using Prilled Urea and Urea Super Granules in T. Aman Rice

An experiment was conducted at the Experimental field of Department of Agronomy, Bangladesh Agricultural University, Mymensingh, during June to December 2007 to evaluate the nitrogen use efficiency of transplant aman rice using prilled urea (PU) and urea super granule (USG). Three rice varieties (BR11, BRRI dhan30 and BRRI dhan39) were compared at three doses of nitrogen, i.e., PU@125 kg N ha-1, USG @170 kg N ha-1 and USG @ 70 kg N ha-1 in a Randomized Complete Block (RCB) design with three replications. USG each weighing 1 g and 2.6 g were placed manually at the depth of 8-10 cm in the middle of four hills in alternate rows at 12 days after transplanting and PU applied in split applications. The rice var. BR11 at USG @70 kg N ha-1 has produced the maximum grain yield (4.75 t ha-1) which was statistically identical to BRRI dhan30 at USG @ 70 kg N ha-1 (1 g pellet-1). The highest nitrogen use efficiency, partial factor productivity and marginal rate of return (1966%) were recorded from the treatment of BR11 at USG @ 70 kg N ha-1.Bangladesh Agron. J. 2015, 18(1): 59-63

Performance of Prilled Urea and Urea Super Granules on the Growth and Yield of Wheat

An experiment was conducted at the Agronomy Field of Sher-e-Bangla Agricultural University, Dhaka-1207 during the period from November 2011 to March 2012 to evaluate the performance of prilled urea and urea super granules (USG) on the growth and yield of wheat varieties. The experiment comprised of four wheat varieties viz., BARI Gom 21, BARI Gom 24, BARI Gom 25 and BARI Gom 26, and five nitrogen (N) levels viz., control (no Nitrogen), 84 kg ha-1 N from USG, and 30, 50 and 70 kg N ha-1 from prilled urea i.e., 67, 112 and 155 kg urea ha-1. The experiment was laid out in a split-plot design with three replications where wheat varieties were placed in the main plot and nitrogenous fertilizers in sub-plots. Experimental results indicated that different varieties had the significant effect on plant height, number of tillers and dry weight plant-1, and number of grains spike-1, grain and straw yield, and harvest index. The variety BARI Gom 24 produced the highest grain yield (2.49 t ha-1) that mainly attributed by the maximum number of spikes plant-1, number of grains spike-1 and 1000-grain weight. Among the different nitrogenous fertilizers 84 kg N ha-1 from USG (1.8 g) gave the highest grain yield (2.69 t ha-1) due to the maximum number of spikes plant-1, maximum number of grains spike-1 and 1000-grain weight. The variety BARI Gom 24 produced the highest grain yield (2.80 t ha-1) with 80 kg N ha-1 from USG application.Bangladesh Agron. J. 2015, 18(1): 37-48

Exploring the potential to improve energy saving and energy efficiency using fertilizer deep placement strategy in modern rice production in Bangladesh

Nitrogen (N) fertilizer plays an important role in modern rice production and is required in large amount because it is the most limited nutrient as well. The fertilizer deep placement (FDP) strategy is developed to improve efficiency of N fertilizer use and rice productivity. The present study estimates the extent of energy saving, productivity and efficiency impacts of FDP strategy in modern rice cultivation at the farm level in Bangladesh using a stochastic production frontier approach. A total sample of 200 rice farmers (100 FDP users and 100 conventional urea users) from a village of Jessore District is utilized. Results reveal that FDP strategy significantly improves energy balance, energy ratio, energy productivity and technical energy efficiency. Relative gains are higher for Boro (dry winter) season than the Aman (monsoon) season. The key policy implication is that a widespread diffusion of FDP strategy should be pursued with priority as it holds the potential to significantly reduce energy use from a scarce, finite and renewable resource (i.e., urea fertilizer) while supporting growth in rice-based agriculture of Bangladesh. Government should also support entrepreneurs to invest in briquetting urea into urea super granules (USG) in order to effectively improve uptake of FDP strategy nationwide.

Floodwater Nitrogen, Rice Yield and N Use Efficiency as Influenced by Deep Placement of Nitrogenous Fertilizers

An experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh during the Aus season of 2012 to investigate the effects of deep placement of nitrogen (N) fertilizers on floodwater NH4-N concentration, rice yield and N use efficiency under alternate wetting and drying (AWD) condition. The experiment was laid out in a randomized complete block design with three replications. There were eight treatment combinations viz. T 1 (Control), T 2 [52 kg N from Urea super granule (USG)], T 3 (104 kg N from USG), T 4 [78 kg N from prilled urea (PU)], T 5 (120 kg N from PU), T 6 (51 kg N from NPK briquette), T 7 (78 kg N from USG) and T 8 (78 kg N from NPK briquette). The results regarding the floodwater NH 4 -N concentration revealed that, the highest value of (NH 4M -N) was observed at the second day of PU application followed by gradual decrease with time. USG and NPK briquette treated plots showed negligible amounts of NH 4 -N in flood water during the sampling periods. The highest grain yield (5265 kg ha -1 ) and straw yield (6434 kg ha -1 ) was recorded from 104 kg N from USG (treatment T 3 ) and the lowest values were obtained from control. Apparent nitrogen recovery by rice plants was much higher when 78 kg N was applied as USG. Nitrogen use efficiency decreased with the increase in N rate either as PU, USG and NPK briquette and treatment T 7 (78 kg N as USG) showed the highest value. These results clearly indicate that the deep placement of N in the form of USG and NPK briquette minimizes the loss of N that results in higher N use efficiency and increased grain yield of rice as compared to broadcast application of N in the form of PU. DOI: http://dx.doi.org/10.3329/jesnr.v7i1.22173 J. Environ. Sci. & Natual Resources, 7(1): 207-213 2014

Growth Parameters of Transplant Aman Rice (cv. BRRI dhan 52) as Influenced by Age of Tiller Seedlings, Number of Tiller Seedlings Hill-1 and Level of USG

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, Bangladesh to investigate the effect of age of tiller seedlings, number of tiller seedlings hill-1 and application of urea super granules (USG) on the growth parameters of transplant aman rice cv. BRRI dhan52. The experiment comprised two ages of tiller seedlings viz. 25 and 35 days old, three levels of tiller seedling hill-1 viz.1, 3 and 5 seedlings hill-1 and three USG levels viz. 0, 1.8 and 2.7g USG. The experiment was laid out in a Randomized Complete Block Design with three replications. The highest and lowest plant height was found by transplanting 25-day and 35-day old tiller seedlings at all dates of observations. By transplanting 35-day old tiller seedlings total dry matter hill-1 was found highest at 15DAT and 45 DAT. Total dry matter hill-1 was the highest in 5 tiller seedlings hill-1 and it was in lowest in 1 tiller seedling hill-1. Plant height was the highest in 5 tiller seedlings hill-1 which was as good as that of 3 tiller seedlings hill-1 and the lowest one was found in 1 tiller seedling hill-1 at 15 DAT. The tallest plant and highest total dry matter hill-1 were observed in 1.8g USG and the lowest one was observed in control treatment. Transplant Aman rice can be grown by transplanting 25-day old tiller seedling, 5 tiller seedlings hill-1 and by applying 1.8g USG for the highest plant height, more tiller and total dry matter production hill-1.DOI: http://dx.doi.org/10.3329/jesnr.v6i2.22104 J. Environ. Sci. & Natural Resources, 6(2): 101-108 2013

Rice Yield Gap Minimization in Central Bangladesh: Using and Adapting Existing Technologies

Rice (Oryza sativa L.) in the dry season (Boro) followed by rice in the wet season (Aman) is the major cereal cropping system in Bangladesh. The average productivity (7 Mg·ha﹣1) of this system is far below attainable yields (14 Mg·ha﹣1) in farmers’ fields, resulting in a large yield gap mainly due to farmers’ traditional management practices. Narrowing yield gap is a vital complementary strategy in improving rice yield and consequently enhancing food security. We evaluated BRRI recommended management practices, BRRI recommended management practices along with two N management options (leaf color chart and Urea Super Granule) and farmers’ crop management practices integrated with quality seed, leaf color chart (LCC) and Urea Super Granule (USG) in farmers’ fields of Kapasia, Gazipur over 6 contiguous seasons during 2009-2012. Across years, all the management options increased grain yields compared with the farmers’ practice (FP) by 1.12 Mg·ha﹣1 in Aman and 0.84 Mg·ha﹣1 in Boro season. The higher yield response (43%) occurred with BRRI recommended management practices followed by BRRI recommended management practices in combination with Urea Super Granule (42%) as N source (BRRI-USG). Yield advantage of 41% could be attained by BRRI recommended management practices with leaf color chart (LCC) aided N management (BRRI-LCC) while this was 22%, 13% and 13% higher than FP (farmer’s practice) when only quality seeds, USG and LCC were used with farmers’ management practice. BRRI Rec., BRRI-LCC and BRRI-USG·management options reduce the yield gap of FP by 41%, with an average of 2.87 Mg·ha﹣1. When farmers adopted FP-QS, FP-USG and FP-LCC management options, they reduced the yield gap of FP by 21%, 13% and 12%, with an average of 1.49, 0.88 and 0.81 Mg·ha﹣1, respectively. The average added net returns with BRRI Rec., BRRI-LCC and BRRI-USG·management options were US$175 to US$362 ha﹣1 in the wet season and US $158 to US $263 ha﹣1 in the dry season. BRRI management practices and BRRI management practices integrated with two N management options, either LCC or USG has the potential to boost rice yield and consequently total rice production in Bangladesh.

Nitrogen use efficiency and rice yield as influenced by the application of prilled urea and urea super granule with or without organic manure

An experiment was conducted to examine the effect of prilled urea (PU), and urea super granule (USG) alone or in combination with poultry manure or cowdung on NH4-N content of rice field with nitrogen use efficiency (NUE) and the yield of rice (cv. BRRI dhan50). The experiment was carried out at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh during Boro season of 2012 and laid out in a randomized complete block design with three replications. There were six treatments viz. T1 (Control), T2 (78 kg N ha-1 from USG), T3 (136 kg N ha-1 from PU), T4 (58 kg N ha-1 from USG), T5 (58 kg N ha-1M from USG + 3 t ha-1 poultry manure) and T6 (58 kg N ha-1 from USG + 5 t ha-1 cowdung). All plots received recommended doses of P, K, S and Zn fertilizers. The NH4-N in rice field water increased rapidly when N was applied as PU. In contrast, NH4-N release was very slow when applied as USG over the crop growth period. Application of PU, USG alone or in combination with poultry manure or cowdung significantly influenced grain and straw yield, all the yield components except 1000-grain weight of BRRI dhan50. Urea super granule with poultry manure (treatment T5) produced the highest grain and straw yield and the lowest values were recorded from control. Nitrogen content and uptake, apparent N recovery and NUE were also influenced significantly by the application of PU, and USG alone or in combination with organic manure. Among the treatments, T5 demonstrated the highest N recovery and NUE. The overall results suggest that application of USG in combination with poultry manure could be considered more effective for increasing the yield and NUE of BRRI dhan50. DOI: http://dx.doi.org/10.3329/jbau.v12i1.21237 J. Bangladesh Agril. Univ. 12(1): 37-43, June 2014

Effect of variety and method of USG placement on the yield performance of transplanted aman rice

A field experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from July to December 2011 to evaluate the effect of variety and placement method of urea super granule (USG) on the yield performance of T. aman rice varieties. The experiment consisted of three aman rice varieties viz., Pajam, BR11, BRRI dhan40 and four placement methods viz., broadcasting method of prilled urea (PU), USG placement by hand, by BAU USG applicator and by BARI USG applicator. The experiment was laid out in a randomized complete block design with four replications. The highest value of grain yield (5.13 t/ha), straw yield (5.90 t/ha) and biological yield (11.04 t/ha) were found in BR11. On the other hand, the lowest grain yield (3.54 t/ha) was produced in variety Pajam. The highest grain and straw yields (5.13 and 5.21 t/ha, respectively) were obtained from the hand placement method of USG. Regarding the interaction of variety and USG placement method, BR11with hand placement method appeared as the best method among others. DOI: http://dx.doi.org/10.3329/jbau.v12i1.21183 J. Bangladesh Agril. Univ. 12(1): 7-12, June 2014

Effect of fertilizer deep placement with urea supergranule on nitrogen use efficiency of irrigated rice in Sourou Valley (Burkina Faso)

The loss of nitrogen (N) can be very high in rice (Oryza sativa L.) fields, particularly in the irrigated rice cropping systems with very poor water control. Previous studies have reported very low (30 %) fertilizer N use efficiency by broadcasting in irrigated cropping systems. The effect of fertilizer N (prilled urea—PU) and briquettes—urea supergranules (USG) on rice yield performance and nutrient uptake was investigated in West Africa. Field experiments were carried out in Sourou valley in Burkina Faso in the wet season of 2012 and dry season of 2013. PU was broadcast applied and USG were point-placed deeply into the soil at 5–7 cm using the same fertilizer N rates (52 kg N ha−1) and two different rice varieties (FKR 19 and NERICA 62N). The results indicate that Fertilizer Deep Placement (FDP) significantly increased grain yields, particularly in the wet season as compared with broadcasting. The FDP applied to NERICA 62N produced the highest tillers and panicles numbers, leading to more yields. In wet season, FDP significantly increased agronomic efficiency by 39.43 % over PU and physiological efficiency by 24.23 %. In the dry season, differences in the average nitrogen use efficiency (NUE) between FDP and PU were not significant. The studies suggest that FDP is genotype and season-specific, and that it can be used by farmers to improve NUE and increase grain yields in the irrigated rice cropping system. Further investigations are underway to understand seasonal and genetic effect on FDP performance.

Is the source–sink relationship in transplanted rice receiving deep-placed urea supergranules dependent upon the geometry of transplanting?

Deep placement of urea supergranules in wetland rice (Oryza sativa L.) or correct urea band application enables to protect nitrogen (N) from various loss mechanisms, but recovering of fertilizer N by plants depends upon geometric and agronomic factors. The objective of this study was to characterize the diffusion of ammoniacal N from the two urea sources, point or line application, in a typical paddy soil. A model of ammonia diffusion was developed for the two geometries. The relation between the N application rate and the transplanting geometry was studied in two fields using probes attached to urea supergranule of different mass (2 and 4 g). The transplanting pattern was adapted for obtaining 58 or 116 kg N ha−1 in the 4 g application. The ammoniacal nitrogen concentration was compared to the diffusion model prediction. The values of the diffusion coefficient were found to be 1.160 and 1.107 cm2 d−1. Ammonia disappearance below 10 mmol L−1 did not follow the same kinetics in the two treatments corresponding to 4 g application. Relative to the 2 g treatment, root ammonia uptake in the 4 g treatment was delayed and slowed in the classical geometry of 20 cm × 20 cm (116 kg N ha−1) when it was mainly delayed in the geometry provided with 58 kg N ha−1. This manipulation of the source–sink relationship enables to foresee possibilities for the development of new fertilizers adapted to wetland rice cultivation.

Effects of PU, USG and NPK briquette on nitrogen use efficiency and yield of BR22 rice under reduced water condition

An experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University, Mymensingh during the aman season of 2012 to investigate the effects of prilled urea (PU), urea super granule (USG) and NPK briquette on NH4- N concentration in field water, yield and nitrogen (N) use efficiency (NUE) of BR22 rice under reduced water conditions. The experiment was laid out in a randomized complete block design with three replications. There were altogether eight treatment combinations viz. T1: Control (No N fertilizer), T2: 52 kg N ha-1 from USG, T3: 104 kg N ha-1 from USG, T4: 78 kg N ha-1 from PU, T5: 120 kg N ha-1 from PU, T6: 51 kg N ha-1 from NPK briquette, T7: 78 kg N ha-1 from USG and T8: 78 kg N ha-1 from NPK briquette. Water samples were collected from rice field for seven consecutive days after deep placement of USG and the first split application of PU and the samples were analyzed for NH4-N. The Highest concentration of NH4-N in water was observed at the second day of PU application followed by gradual decrease with time. The yield contributing characters like plant height, panicle length, number of effective tillers hill-1 and grains panicle-1 were significantly influenced by different treatments. The highest grain yield of 3.93 t ha-1 was recorded from 104 kg N ha-1 as USG (T3) and the lowest value of 2.12 t ha-1 was obtained from control. The N use efficiency was increased when the N was applied as USG. The overall results revealed that application of USG and NPK briquette may be practised for obtaining better yields in addition to increasing the efficiency of N fertilizer. DOI: http://dx.doi.org/10.3329/jbau.v11i2.19897 J. Bangladesh Agril. Univ. 11(2): 215-220, 2013

Performance of transplant Aman rice as influenced by tiller seedlings and nitrogen management

An experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from July to December 2012 to observe the effect of variety, age of tiller seedling used for transplanting and nitrogen management on the yield performance of transplant Aman rice. The experiment consisted of two varieties viz. BRRI dhan49 and BRRI dhan51, two ages tiller seedling viz. 25- and 35-day old, five nitrogen management viz. control (no urea), application of prilled urea @ 215 kg ha-1 (1/2 at 15 DAT+1/2 at 30 DAT), prilled urea @ 215 kg ha-1 (1/3 at 15DAT+1/3 at 30DAT+1/3 at 45DAT ), urea super granules (USG) 1.8 g and USG 2.7 g four-hill-1 in every alternate row. The experiment was laid out in randomized complete block design with three replications. The results revealed that higher plant characters, straw yield and harvest index were obtained from BRRI dhan49 compared to BRRI dhan51. Older seedlings (35-day old) produced higher grain yield to younger seedlings. The highest yield contributing characters and grain yield were obtained when 1.8g USG was applied. The grain yield was highest in 35-day old tiller seedlings of BRRI dhan51 while fertilized with 1.8g USG. This value was lowest when 25-day old tiller seedlings of BRRI dhan51 were fertilized with prilled urea in two split applications. It may be concluded that 35-day tiller seedlings of BRRI dhan51 fertilized with USG 1.8 g four-hill-1 could be used for achieving higher yield of transplant Aman rice. DOI: http://dx.doi.org/10.3329/jbau.v11i2.19903 J. Bangladesh Agril. Univ. 11(2): 249-256, 2013

Effet de l’urée et du NPK 15-15-15 perlés et super granulés sur la productivité des variétés de riz IR841 et NERICA-L14 en zone de bas-fond au Sud-Bénin

Objectives: The study was carried out on the site of Koussin and Lélé in the southern Benin, exploring the efficiency of the supply of the pearl and super granule urea (46%) and NPK 15-15-15 for rice production in the inland valley. Specifically, the study aims to assess the effect of the different forms of urea and NPK 15- 15-15 on the growth and yield parameters of two inland rice varieties (IR841 and NERICA-L14) widely adopted in cultivated lowland of Benin. Methodology and results: The experimental design is a split-plot with two rice varieties, four forms of fertilizer (pearl urea + NPK; pearl urea + super granule NPK; super granule urea + pearl NPK and super granule urea + super granule NPK) in four replications. The growth and yield parameters were assessed. Super granule urea + super granule NPK and super granule urea + pearl NPK have significantly (P < 0.0001) induced higher plant height, numbers of tiller and rice grain per panicle compared with the other treatments whatever the rice variety. However, mean yields of paddy rice and straw were significantly higher (P < 0,0001) for super granule urea + super granule NPK (paddy rice yield : 5,52 ± 0,26 t/ha ; straw yield : 12,19 ± 0,54 t/ha) and super granule urea + pearl NPK (paddy rice yield: 4,82 ± 0,22 t/ha ; straw yield : 10,79 ± 0,61 t/ha). In general with these treatments, the highest yields were recorded with IR841 rice variety. Conclusion and application: The super granule fertilizers are recommended for improving rice production in the inland valley as they improve substantially the yields. In order to improve the efficiency of these fertilizers especially the sources of nitrogen, the study suggests to supply urea super granule + NPK super granule or urea super granule + pearl NPK to improve growth and yields parameter of IR841 rice variety.Keywords: inland valley; super granule fertilizer; soil fertility; irrigated rice production; Benin.

Effet de l’urée et du NPK 15-15-15 perlés et super granulés sur la productivité des variétés de riz IR841 et NERICA-L14 en zone de bas-fond au Sud-Bénin

Objectives: The study was carried out on the site of Koussin and Lélé in the southern Benin, exploring the efficiency of the supply of the pearl and super granule urea (46%) and NPK 15-15-15 for rice production in the inland valley. Specifically, the study aims to assess the effect of the different forms of urea and NPK 15- 15-15 on the growth and yield parameters of two inland rice varieties (IR841 and NERICA-L14) widely adopted in cultivated lowland of Benin. Methodology and results: The experimental design is a split-plot with two rice varieties, four forms of fertilizer (pearl urea + NPK; pearl urea + super granule NPK; super granule urea + pearl NPK and super granule urea + super granule NPK) in four replications. The growth and yield parameters were assessed. Super granule urea + super granule NPK and super granule urea + pearl NPK have significantly (P < 0.0001) induced higher plant height, numbers of tiller and rice grain per panicle compared with the other treatments whatever the rice variety. However, mean yields of paddy rice and straw were significantly higher (P < 0,0001) for super granule urea + super granule NPK (paddy rice yield : 5,52 ± 0,26 t/ha ; straw yield : 12,19 ± 0,54 t/ha) and super granule urea + pearl NPK (paddy rice yield: 4,82 ± 0,22 t/ha ; straw yield : 10,79 ± 0,61 t/ha). In general with these treatments, the highest yields were recorded with IR841 rice variety. Conclusion and application: The super granule fertilizers are recommended for improving rice production in the inland valley as they improve substantially the yields. In order to improve the efficiency of these fertilizers especially the sources of nitrogen, the study suggests to supply urea super granule + NPK super granule or urea super granule + pearl NPK to improve growth and yields parameter of IR841 rice variety.Keywords: inland valley; super granule fertilizer; soil fertility; irrigated rice production; Benin.

Effect of spacing of transplanting, rate and depth of placement of urea super granules (USG) on the yield of BORO rice

Effect of spacing of transplanting, rate and depth of placement of urea super granules (USG) on the yield of BORO rice

Physiological Attributes of Transplant <i>Aman</i> Rice (Cv. Brri Dhan52) as Affected by Tiller Seedlings and Urea Super Granules

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, Bangladesh to investigate the effect of age of tiller seedlings, number of tiller seedlings hill-1 and application of urea super granules (USG) on some physiological attributes of transplant Aman rice cv. BRRI dhan52. The experiment consisted of two ages of tiller seedlings viz. 25- and 35-day old, three levels of tiller seedlings hill-1 viz.1, 3 and 5 seedlings hill-1 and three USG levels viz. 0, 1.8g and 2.7g USG per four hills in every alternate row. The experiment was laid out in a randomized complete block design with three replications. The effect of age of tiller seedlings, number of tiller seedlings hill-1 and USG application were significant on crop growth rate (CGR), relative growth rate (RGR), net assimilation rate (NAR) and leaf area index (LAI). The highest CGR and RGR were found by transplanting 35-day old tiller seedlings during the period at 15-30 and 60-75 DAT when 5 tiller seedlings hill-1 were transplanted. The highest NAR was observed at 60-75 DAT with transplanting 5 tiller seedlings hill-1 and the lowest one was recorded at 30-45 DAT. The highest LAI was found at 35-day old tiller seedlings during the period at 60 and 75 DAT when 5 tiller seedlings hill-1 were transplanted. CGR and RGR were found highest by applying 1.8 g USG at 45-60 and 60-75 DAT while NAR was the highest with application of 2.7g USG at 60-75 DAT and lowest one was found in control (0 g USG) at 45-60 and 60-75 DAT. The highest LAI was found by applying 1.8g USG at 15, 30, 45 and 60 DAT and the lowest one was found at 60 DAT in control and at 15, 30 and 45 DAT when 2.7g USG was applied. The highest LAI and CGR were found in older tiller seedlings (35- day old) by transplanting five tiller seedlings hill-1 fertilized with 1.8g USG whereas the highest RGR and NAR were obtained in younger tiller seedlings (25-day old) by transplanting single tiller seedling hill-1 fertilized with 1.8g USG per four hills of every alternate row.DOI: http://dx.doi.org/10.3329/pa.v24i1-2.19094 Progress. Agric. 24(1&2): 17 - 27, 2013

Evaluation of Urea Super Granule as a Source of Nitrogen in Transplant <i>Aman</i> Rice

An experiment was carried out at Bangladesh Agricultural University, Mymensingh to evaluate the effect of urea super granule (USG) as a source of nitrogen on the yield and yield components of transplant Aman rice cv. BRRI dhan39, BRRI dhan46 and BINA dhan7. Five levels of N (viz., 0, 60, 120 kg ha-1 as prilled urea and 60 and 120 kg ha-1 as USG) were taken as experimental treatments. The experiment was laid out in a randomized complete block design with three replications. Plant height, effective tillers hill-1, grains panicle-1 and grain yield varied significantly due to different cultivars. All the yield and yield components except 1000-grain weight were influenced significantly by the levels of nitrogen fertilizer. The highest grain yield (4.82 t ha-1) was recorded in BINA dhan7 and the lowest one (4.30 t ha-1) was recorded in BRRI dhan39. Nitrogen @ 120 kg ha-1 as USG performed the best among the treatments in respect of yield and yield components of rice. The highest grain yield (5.46t ha-1) was obtained from BINA dhan7 with 120 kg N ha-1 as USG which was statistically identical with 60 kg N ha-1 as USG. A considerable amount (31.25%) of prilled urea (PU) nitrogen could be saved by using USG. It may be concluded that USG could be used as N management to achieve better nitrogen use efficiency in reducing N loss than the PU.DOI: http://dx.doi.org/10.3329/pa.v24i1-2.19095 Progress. Agric. 24(1&2): 29 - 37, 2013