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101.
Mukund D. Patil Bhabani S. Das Eran Barak Pratap B. S. Bhadoria Amir Polak 《Paddy and Water Environment》2010,8(2):189-198
Polymer-coated urea (PCU) is an important alternative to uncoated urea for improving nitrogen (N) use efficiency (NUE). Only
a few studies discuss their utility for lowland rice systems. A 2-year field study was conducted to examine if nitrogen loading
is reduced in lowland rice ecosystem by using mixture of PCU and uncoated urea without sacrificing yield. Five treatments
involving two mixtures of PCU with 50 and 70% coated urea each at 70 and 50% of recommended dose (80 kg N ha−1) and one with uncoated urea at 100% recommended dose were laid out in a completely randomized design. Selected plant growth
parameters and plant available N contents (NH4–N plus NO3–N) in soil solution and ponded water were measured over a period of 65 days after transplanting. Results showed no significant
difference for vegetative and yield parameters among different treatments suggesting that treatments receiving lower doses
of nitrogen exhibited higher NUE. Analysis of partial factor of productivity (PFP) for N suggested that the total N dose may
be reduced by 50% using mixtures of coated and uncoated urea. Similarly, statistically similar PFP values for treatments receiving
the same amount of total N for both years and for both total N dose suggested that the proportion of coated urea may also
be reduced to as low as 50% without sacrificing yield. Correlation analysis on nitrogen contents in ponded water and soil
solutions and the analysis of water productivity and PFP showed that soil water regime could also significantly influence
the nitrogen status in soil even when PCU are applied. In turn, both the water regime and N contents in soil ultimately influences
grain yield. Although the constant release of N from coated fertilizer ensures adequate N supply for plant uptake, it may
not completely avoid N deficit condition especially during heavy rainfall. Analysis of the developed production function suggested
that 55–65% polymer coating and about 100 cm total water input may be ideal for achieving maximum yield. The production function
was developed for PCU treatments using data observed in treatments receiving 70% recommended N dose. The range of water input
in these treatments was 86.5–174.0 cm. 相似文献
102.
Sumit Kumar Dey Radha Prasanna Devesh Pratap Shiv Dhar Singh Tapan Jyoti Purakayastha 《Archives of Agronomy and Soil Science》2017,63(13):1927-1937
Climate change, as a result of increase in the concentration of greenhouse gases, influences growth and productivity of leguminous crops. A study was carried out to analyse the impacts of elevated carbon dioxide (CO2) and cyanobacterial inoculation on growth, N2 fixation and N availability and uptake in cowpea crop, under different doses of phosphorus. Cowpea crop was grown under ambient (400 µmol mol?1) and elevated (550 ± 20 µmol mol?1) CO2 levels using Free-Air Carbon dioxide Enrichment facility. Elevated CO2 level increased chlorophyll content in leaves, improved nodulation and nitrogen fixation by the crop. Increase in P dose up to 16 mg kg?1 soil enhanced nodule development and N2 fixation under high CO2 condition. Cyanobacterial inoculation increased nodule weight, leghaemoglobin content in nodules and total nitrogenase activity. Although nitrogen concentration in cowpea seeds decreased in high CO2 treatment, higher N uptake was recorded. Under elevated CO2 condition, cyanobacterial inoculation and higher P doses led to enhanced root growth and N2 fixation and availability of soil nitrogen. The study illustrated the synergistic effect of high CO2 and cyanobacterial inoculation in enhancing crop growth and availability of soil N, mediated by biological N2 fixation in cowpea under different levels of P. 相似文献
103.
104.
Kashyap Sarvesh Pratap Kumari Nishi Mishra Pallavi Moharana Durga Prasad Aamir Mohd 《Genetic Resources and Crop Evolution》2021,68(6):2207-2233
Genetic Resources and Crop Evolution - Crop breeding for abiotic stress tolerance entails introgression of stress tolerant genes into the cultivated types. With the augmentation in salt tolerance,... 相似文献
105.
Sanjeev Gupta Debjyoti Sen Gupta Tuba K. Anjum Aditya Pratap Jitendra Kumar 《Euphytica》2013,193(1):27-37
Yellow Mosaic disease (YMD) is one of the most destructive diseases of blackgram (Vigna mungo) causing heavy yield losses every year. Mungbean Yellow Mosaic India Virus (MYMIV) is one of the YMD causing begomoviruses prevalent in the major blackgram growing area (northern and central part) of India. Inheritance of MYMIV resistance gene was studied in blackgram using F1, F2 and F2:3 derived from cross DPU 88-31(resistant)× AKU 9904 (susceptible). The results of genetic analysis showed that a single dominant gene controls the MYMIV resistance in blackgram genotype DPU 88-31. The F2 population from the same cross was also used to tag and map the MYMIV resistance gene using SSR markers. Out of 361 markers, 31 were found polymorphic between the parents. However, marker CEDG 180 was found to be linked with resistance gene following the bulked segregant analysis. This marker was mapped in the F2 mapping population of 168 individuals at a map distance of 12.9 cm. The validation of this marker in nine resistant and seven susceptible genotypes has suggested its use in marker assisted breeding for developing MYMIV resistant genotypes in blackgram. 相似文献
106.
Joykrushna Jena Pratap Chandra Das Suman Mondal & Rupa Das 《Aquaculture Research》2007,38(10):1061-1065
The compatibility and growth performance of silver barb Puntius gonionotus (Barbonymous gonionotus) with the three Indian major carps, i.e., Catla catla, Labeo rohita and Cirrhinus mrigala, were assessed in a 10‐month carp polyculture trial. Treatments T‐1, T‐2, T‐3 and T‐4 were stocked with three of the above four carp species, with an absence of silver barb, mrigal, rohu and catla, respectively, while all four species were stocked in treatment T‐5. The treatments were stocked at 6000 fingerlings ha−1, with an equal species ratio maintained in each treatment. Incorporation of silver barb into the polyculture system neither affected the survival of any carp irrespective of species combination nor yielded significant changes in biomass production among treatments, except for the one without catla, where it was significantly low. The study revealed a higher extent of competition between silver barb and rohu, perceptible from the lower growth of one in the presence of the other. Although a certain level of competition of silver barb with mrigal was evident, competition with catla was not perceptible. Irrespective of species combination with silver barb as a component species, similar total biomass production in treatments revealed the feasibility of its incorporation into the Indian major carp‐based polyculture practice without affecting the total yield. 相似文献
107.
The study was undertaken to evaluate the relative efficiency of different Gramineae genera for haploid induction in triticale (x Triticosecale) and triticale × wheat (Triticum aestivum) hybrids through the chromosome elimination (wheat × maize, Zea mays) system. Eight intergenotypic triticale and 15 triticale x wheat crosses were subjected to hybridization with nine different Gramineae genera viz., Z. mays, Sorghum bicolor, Pennisetum americanum, Setaria italica, Festuca arundinacea, Imperata cylindrica, Cynodon dactylon, Lolium temulentum and Phalaris minor in two separate experiments. This was followed by in vivo auxin treatment of the crossed spikes and subsequent rescue of the haploid embryos to regenerate green haploid plantlets. All the triticale and triticale x wheat crosses resulted in seed set in variable frequencies when hybridized with maize, I. cylindrica, pearl millet and sorghum. Seed set was also obtained with S. italica, F. arundinacea and P. minor in a few crosses in both groups. In general, all the triticale x wheat crosses, except for one in each case, resulted in embryo formation and green haploid plantlet regeneration when hybridizations were carried out with maize and I. cylindrica. However, the latter outperformed the former in embryo formation (25.48% vs. 20.0%) and regeneration (34.17% vs. 15.10%) frequencies, the differences being significant for regeneration frequencies. In the case of triticale hybrids, no significant differences between maize and I. cylindrica were observed for the three parameters of haploid induction. Embryo formation and regeneration were also observed in some of the triticale as well as triticale × wheat F1 hybrids when hybridized with sorghum and pearl millet. 相似文献