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41.
Nitrogen-15 balance in transplanted and direct-seeded flooded rice as affected by different methods of urea application 总被引:1,自引:0,他引:1
H. F. Schnier M. Dingkuhn S. K. De Datta E. P. Marqueses J. E. Faronilo 《Biology and Fertility of Soils》1990,10(2):89-96
Summary Alternative N-fertilizer management practices are needed to increase productivity and the N-use efficiency of flooded rice (Oryza sativa L.). In the 1987 dry season, a field study using 15N-labeled urea evaluated the effect of the time and method of fertilizer-N application on grain yield and N-use efficiency in transplanted and direct-seeded flooded rice. Conventional fertilizer application (broadcasting and incorporation) was compared with band placement of liquid urea and point placement of urea supergranules. With band or point placement, the grain yields were significantly greater, and the partial pressure of NH3 (pNH3) in the floodwater was significantly reduced. In the transplanted rice, conventional fertilizer-N application gave a 64% total 15N recovery and 38% crop (grain and straw) recovery. Band placement of liquid urea N resulted in 92% total and 73% crop recovery. In the direct-seeded flooded rice, a conventional N application gave 72% total and 42% crop recovery; band placement, 98% total and 73% crop recovery; and urea supergranule point placement, 97% total and 75% crop recovery.Dedicated to Prof. Dr. K. Mengel, Giessen, FRG, in honor of his 60th birthday. 相似文献
42.
Tanushree Mondal Jayanta Kumar Datta Naba Kumar Mondal 《Archives of Agronomy and Soil Science》2013,59(1):55-72
Experiments were conducted on mustard (Brassica campestris cv.B9) in an old alluvial soil zone of Crop Research and Seed Multiplication Farm, Burdwan University, Burdwan, West Bengal, India, during the winter seasons of 2011–2012 and 2012–2013. The aim was to evaluate the use of vermicompost prepared from municipality waste and Eichhornia mixture and its efficacy on crop growth and yield. Different combined doses of vermicompost, dried cow dung and chemical fertilizer along with Azotobacter and phosphate-solubilizing bacteria compared to full recommended dose of chemical NPK fertilizer (100:50:50) were used to develop an alternative farming technology for sustainable crop production and conservation of natural resources. The variety B9 gave a significantly higher seed yield and oil content along with other growth and yield-contributing factors as well as being the most economically viable option against treatment T4 (i.e. 75% NPK + vermicompost at 2.5 tons per hectare) among all the treatments applied for the experiment and was found to be superior to other treatments in old alluvial soil of Burdwan, India. In both the experimental years, seed yield and oil content were found to be the best for the treatment T4 and was better than using chemical fertilizer. 相似文献
43.
Abir Dey Brahma S. Dwivedi Siba P. Datta Mahesh C. Meena Binay K. Agarwal 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):54-62
In Indian agriculture, nitrogen (N) and phosphorus (P) fertilizers are predominantly used by the farmers, often ignoring secondary and micronutrients. Significance of boron (B) in nutrient management studies has been increasingly underlined under intensive cropping systems particularly in acid soils. In order to understand the distribution of soil native B in different fractions and their contribution to plant B uptake as influenced by nutrient management, soil samples collected after wheat (2009–2010) from a long-term experiment (LTE) continuing since 1972–1973 on Typic Paleustalf of Ranchi were subjected to sequential fractionation of soil B. Treatments included N alone, NP, NPK, 150% of recommended NPK, NPK + farmyard manure (FYM), NPK + lime, and an unfertilized-control. Five soil B fractions were determined along with hot CaCl2-extractable (available) B. Averaged across the treatments, the soil had low organic carbon (C), pH and cation exchange capacity (CEC), and high free sesquioxides. Total B content was 21.7 mg kg?1. Among different B fractions, residual B was the major contributor to total B and other fractions collectively shared 7% of total B only. Application of N alone depleted readily soluble, specifically adsorbed and organically bound B bringing the contents even below unfertilized-control. Conjoint use of lime or FYM with NPK increased significantly these fractions, whereas a decrease in oxide bound B was noticed under these treatments. Available B was positively correlated with these fractions indicating their significance in controlling B availability in the soil. The study revealed that use of lime or FYM helped modifying the distribution of soil B in different fractions by way of changing soil pH and organic C content, resulting in enrichment of plant available pool. A drastically low available B content in different treatments receiving fertilizers alone, however, suggested the necessity of B fertilization at prescribed rates for maintaining soil B fertility as also high crop yields. 相似文献
44.
Marta Vasconcelos Valerie Musetti Chee-Ming Li Swapan K. Datta Michael A. Grusak 《Soil Science and Plant Nutrition》2013,59(7):1151-1157
Iron deficient soils limit crop production on 25-30% of the world's arable land. Both grasses (Strategy 11) and dicotyledonous crops (Strategy 1) are susceptible to iron deficiency, but each respond to iron stress by different mechanisms. In order to acquire iron from the soil, Strategy I plants utilize an iron reduction and Fe2+ transporter system at the root level, whereas Strategy 11 plants use a phytosiderophore-based system. Unfortunately, in some grasses such as rice, the production of phytosiderophores is low, and thus their ability to survive in iron-deficient conditions is limited. To determine whether a Strategy I root reductase can function in a Strategy 11 plant, and enhance its iron acquisition, we inserted the FRO2 gene from Arabidopsis thaliena (AtFR02) into rice (Oryza sativa). Root reductase activity was determined and was found to be low in both transgenic and control plants grown at different iron concentrations. The low activity levels were attributed to the release of soluble reductants in the assay and not to membrane-localized root reductase activity. RT-PCR analysis of rice roots and shoots of plants grown hydroponically at different iron concentrations revealed no expression of the transgene. In this paper, we discuss the lack of functionality of the AtFRO2 gene in rice, and we perform a comparative study of the 0.6 kb promoter region by PlantCARE and PLACE analysis. 相似文献
45.
Prasenjit Ray Siba Prasad Datta Brahma S. Dwivedi 《Soil Science and Plant Nutrition》2013,59(6):628-637
Use of wastewater for irrigating agricultural crops is on the rise, particularly in the developing countries. The present study was undertaken to assess the long-term effect of irrigation with zinc smelter effluent on important soil properties including heavy metal status. Metal concentration in the edible parts of the crops grown on smelter effluent-irrigated soils was also measured. For this purpose, the agricultural lands which have been receiving the zinc smelter effluent irrigation for about five decades at Debari, Udaipur, India were selected. The adjacent tubewell water-irrigated fields were selected as reference. Long-term irrigation with smelter effluent resulted into significant buildup of ethylenediaminetetraacetic acid extractable Zn (57.7 fold), Cu (4.51 fold), Fe (3.35 fold), Mn (1.77 fold), Ni (1.20 fold), Pb (45.1 fold), and Cd (79.2 fold) in soils over tubewell water-irrigated fields. Total Zn, Cu, Mn, Ni, Pb, and Cd content in effluent-irrigated soils was also increased by 27.0, 1.60, 1.40, 1.30, 26.2, and 167 fold, respectively. Risk assessment indicated a very high to moderate potential ecological risk due to Cd, Pb, and Zn in soils close to the immediate vicinity of the smelter plant. Cadmium and Pb concentrations in edible parts of almost all the crops grown on effluent-irrigated soils were above the safe limit of CODEX commission. On an average, soil pH dropped by 0.31 units due to smelter effluent irrigation. Smelter effluent irrigation resulted into significant increase in soil organic carbon, electrical conductivity, and CaCO3 content. On an average, there was decrease in available N (21.0%) and P (20.8%) content in effluent-irrigated soils over the tubewell water-irrigated ones. An increase in available K (102%) and S (26.0 fold) was recorded in effluent-irrigated soils. Long-term irrigation with zinc smelter effluent resulted into reduced microbial activities in soil as evidenced from the level of microbial biomass carbon and dehydrogenase activity. In view of the buildup of heavy metals and subsequent imbalance in essential plant nutrients in smelter effluent-irrigated soils, appropriate remediation-cum-fertilization strategy needs to be adopted for better soil health and plant nutrition. 相似文献
46.
Herbicides are typically used as the primary method of weed control. Since common reed (Phragmites australis subsp. australis) infestations in terms of density are relatively large in the State of Nebraska, USA, determining the most appropriate timing of herbicide application is critical for developing a weed management programme. Therefore, several field studies were conducted in 2007 and 2008 at three locations along the Platte River, Nebraska, with the aim of assessing the effect of herbicide selection and timing of application on common reed control. Three herbicides (glyphosate, imazapyr, and imazamox) were applied either alone at two doses or as two-way mixtures on three growth stages of common reed, including vegetative, flowering, and seed filling stages. Both doses of imazapyr (280 and 560 g active ingredient [a] ha?1) provided the highest level of control (≥ 92%) across all three timings, while imazamox provided the lowest level of control. For example, imazamox applied alone at 280 and 560 g a ha?1 provided poor control (≤ 60%) across all three timings at the highest rating date. Imazapyr and glyphosate provided the highest levels of control (90%) by the end of the first growing season and into the next growing season (390 to 450 days after treatment, DAT), regardless of the herbicide application time. Imazamox and glyphosate provided the lowest level of control (< 30%) at the first application time at 450 DAT, but slightly improved control with later timings (74% and 85% control at the flowering and seed filling stages, respectively). Stem density decreased in all herbicide applications and timings except for imazamox at both doses during the vegetative growth stage, which was not significantly different than the untreated control. 相似文献
47.
Santiago M. UlloaAvishek Datta Chris BrueningGeorge Gogos Timothy J. ArkebauerStevan Z. Knezevic 《Crop Protection》2012,31(1):1-7
Time of day has been observed to affect flaming efficacy. The basis for the differential plant response is not well understood; however, daily variation in leaf relative water content (RWC) is thought to contribute to the response. Leaf RWC is the ratio of the amount of water in the leaf tissue compared to when fully turgid. To determine the influence of leaf RWC in plant response to propane flaming, greenhouse experiments were conducted during April and repeated in September of 2009. Two crops [4-leaf maize (Zea mays) and second trifoliate soybean (Glycine max)] and two weed species [5-leaf velvetleaf (Abutilon theophrasti) and 6-leaf green foxtail (Setaria viridis)] were flamed with four propane doses of 0, 29, 43 and 87 kg ha−1 at 0, 4, 8 and 12 h after sunrise-HAS. Leaf RWC was measured before treatment application. Flaming treatment was conducted utilizing a hand flamer with one VT 2-23 C vapor phase burner positioned 20 cm above soil surface and angled horizontally at 30°. The propane pressure was 120 kPa and the application speeds were 1.6, 3.2 and 4.8 km h−1. The plant responses evaluated were plant injury and fresh weight at 7 days after treatment (DAT). All plant species were more susceptible to flaming during the afternoon when they had lower leaf RWC at 8 HAS; however, the response of these plants did not differ with the plants flamed at 12 HAS. Green foxtail flamed at 87 kg ha−1 at 0, 8 and 12 HAS had injury of 62, 76 and 82%, respectively. The same response was observed in velvetleaf which had 80% injury when flamed with 87 kg ha−1 at 0 HAS and 93% injury when flamed at 12 HAS with the same propane dose at 7 DAT. Similar trends occurred for maize and soybean suggesting that leaf RWC could be one of the factors affecting plant response to flaming. Practical implication is that flaming operation should be conducted in the afternoon in order to improve efficacy of weed control and reduce propane consumption rate. 相似文献
48.
Krishna Datta Puri Sunder Man Shrestha Gopal Bahadur Khhatri Chhetri Krishna Dev Joshi 《Euphytica》2009,165(3):523-532
Rice blast (Magnaporthe
oryzae) is the most destructive and epidemic disease of rice. Use of host resistance is the best alternative for disease management.
The leaf and neck blast resistance of 182 rice breeding lines were assessed for leaf and neck blast and classified relative
to a susceptible check-Masuli and resistant check-Laxmi, from greenhouse experiment in 2005 and 2006. The test plants were
inoculated with 105 conidial suspension/ml of M. oryzae at 21 days old seedlings for the leaf blast, and at neck base for the neck blast. Among them, for leaf blast, 77 rice lines
were resistant, 43 were moderately resistant, 39 were moderately susceptible and 23 were susceptible. While among the selected
31 rice lines evaluated for neck blast, 4 lines were resistant, 4 were moderately resistant, 16 were moderately susceptible
and 7 were susceptible. Leaf and neck infection was significant and positively correlated (r = 0.30, P = 0.05). The rice lines, Barkhe 1032, Barkhe 1034, Barkhe 1035, Barkhe 1036, Barkhe 2014, Barkhe 2024, Barkhe 3019, Super
3004 were resistant to leaf blast and Barkhe 1006, Barkhe 1032, Barkhe 1035, Barkhe 3004 were resistant to neck blast. The
rice lines with identification # 11, 69, 137, 168, 182 from Masuli × MT4 parentage, and Barkhe 3017 were susceptible to both
leaf and neck blast. Progenies of Irradiated Pusa Basmati (IPB), Kalinga III/IR64 (KIII/IR64), and Masuli/IR64 were resistant
to both leaf and neck blast. However, most progenies from Masuli/MT4 showed susceptible reaction to both leaf and neck blast.
Thus, rice lines form the IPB, KIII/IR64 and Masuli/IR64 will be promising resistant sources for rice blast in breeding programme. 相似文献
49.
Trisha Roy Samar Chandra Datta Abhijit Sarkar Siddhartha Sankar Biswas 《Archives of Agronomy and Soil Science》2018,64(11):1564-1581
Non-renewable nature of rock phosphate (RP) reserves coupled with open ended nature of P cycle makes it imperative for maximum utilization of available P resources. In this context, use of Indian RPs from Purulia and Udaipur along with citric acid loaded nanoclay polymer composite (CA-NCPC) as P source to costly diammonium phosphate (DAP) was investigated through an incubation experiment followed by a greenhouse experiment with wheat-rice cropping sequence in a Luvisol (pH 5.14, available P 13.5 mg kg?1). Soil available P, crop yield parameters and dynamics of soil P fractions were taken to judge the efficacy of CA-NCPC in solubilizing RPs. Application of CA-NCPC and DAP resulted in 82% and 69% increase in available P over control, respectively under incubation study. Direct effect of treatment receiving CA-NCPC + RP on yield and P uptake by wheat was comparable with DAP but residual impact of CA-NCPC + RP (16.7 g pot?1) was better than DAP (13.8 g pot?1) in rice. The changes in inorganic P fractions were also significant as inclusion of RP increased calcium-P from 16.1 to 61.5 mg kg?1. Results indicated potentiality of RPs treated with CA-NCPC as an alternate P source which could prove promising amidst P scarcity. 相似文献
50.
A. Purohit S. Ganguly G. Ghosh R. Kundu Chaudhuri S. Datta D. Chakraborti 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):73-84
Soft rot of Chinese cabbage is a disease of great economic importance to the State of Pernambuco, Brazil. The present study aimed to evaluate the effect of two calcium sources in different concentrations (calcium nitrate [Ca(NO3)2] at 0, 0.15 and 0.3 g l?1 and calcium chloride (CaCl2) at 0, 1 and 5 g l?1) that were applied through two methods (leaf spraying and soil drenching) on the control of soft rot. Further, it aimed to analyze calcium absorption by the plant and to determine calcium’s role in leaf and cell structure using microscopy. Ca(NO3)2 applied by both methods was effective in controlling soft rot caused by Pectobacterium carotovorum subsp. carotovorum, as it reduced the disease by up to 48.5 % when sprayed onto the leaves (0.15 g l?1). A significant increase in the leaf calcium content was observed only in the plants that were sprayed with higher doses of Ca(NO3)2 and CaCl2. In all of the calcium treatments, light microscopy analyses revealed an increased number of chloroplasts and improved structuring of the palisade parenchyma, while transmission electron microscopy analyses revealed an increased cell wall thickness that was especially evident for the 0.15 g l?1 Ca(NO3)2 treatment applied by leaf spraying and soil drenching. 相似文献