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41.
Abhay Omprakash Shirale Bharat Prakash Meena Priya Pandurang Gurav Sanjay Srivastava Ashis Kumar Biswas Jyoti Kumar Thakur 《Journal of plant nutrition》2013,36(19):2682-2701
Potassium (K) is one of the essential nutrients required by crops in large quantities; however, its use in agriculture by farmers is less than required in developing countries. This neglect has led to excess mining of K in soils by crop plants and has resulted in a negative balance of K in soils. This loss necessitates the need of more use of potassium fertilizers in agriculture. Rocks and minerals offer a potential fertilizer to utilize in agriculture as source of K. The crop trials revealed that feldspar, mica, glauconite, nepheline and shoenite are good sources of K for crops, especially in highly weathered acid soils. However, some researchers have reported no agronomic benefit of feldspar or granite rock application to crops. Overall the size modification, acidulation, microbial inoculants and preparation of K-enriched compost are the effective techniques to utilize K-bearing rocks and minerals. Very limited information is available on these aspects. Thus, in this review, an attempt has been to consolidate up-to-date information of indigenous rocks and minerals as possibilities for alternate sources of K for crop plants. Moreover, this area of research needs attention to utilize indigenous K sources, which can aid to limit the import and cost, of the establishment of potash fertilizer-based industries in developing countries. 相似文献
42.
Fouad H. Jaber Sanjay Shukla Peter J. Stoffella Thomas A. Obreza Edward A. Hanlon 《Compost science & utilization》2013,21(3):194-202
Experiments were conducted on calcareous and sandy soils to investigate the effects of organic amendments for vegetable production on groundwater nitrogen (N) concentration in south Florida. The treatments consisted of applying yard and food residuals compost, biosolids compost, a cocompost of the municipal solid waste and biosolids, and inorganic fertilizer. Nitrate nitrogen (NO3-N), ammonium nitrogen (NH4-N), and total N concentrations were collected for a period of two years for both soils. Statistical analysis results revealed that for the three species tested, there were no significant differences among treatments. NO3-N concentrations for all treatments remained less than the maximum contamination level (10 mg/L). NO3-N transport to groundwater was higher in calcareous soil (mean=5.3 mg/L) than in sandy soil (mean=0.6 mg/L). NH4-N concentrations ranged from 0 to 13.6 mg/L throughout the experiment. Calcareous soil had lower NH4-N concentrations (mean=0.1 mg/L) than sandy soils (mean=0.7 mg/L). Total N ranged from 0.4 to 21.7 mg/L for all treatments for both soils reflecting high adsorption of dissolved organic N in both soils. Overall, results indicated that all the compost treatments were comparable to inorganic fertilizer with regard to N leaching and N concentrations in the groundwater while producing similar or higher yields. 相似文献
43.
Md. Qumruzzaman Chowdhury Swapan Kumar Sarker Jiban Chandra Deb Sanjay Saha Sonet 《Wood Science and Technology》2013,47(4):797-813
Timber species grouping (TSG) is essential for meaningful and cost-optimal use of wood. Bangladesh forests are exceedingly diverse and comprise many woody species which are potentially suitable for versatile uses including structural materials. Traditionally, widely known tree species are used for structural timber because technological properties of most of the species are poorly known. In this study, a hierarchical agglomerative cluster analysis based on three selected wood properties [i.e., wood density, modulus of elasticity (MOE) and modulus of rupture (MOR)] of seventy-nine timber species was done. The clustering process led to the formation of four distinct species groups [i.e., very low (TSG1), low (TSG2), medium (TSG3) and high (TSG4)]. However, the species grouping patterns also varied from trait to trait. This might be due to moderate relationship between density and MOE (r 2 = 0.46) or MOR (r 2 = 0.52). Species of the TSG1 group are mainly characterized by extremely low trait values, while the TSG4 group consists of species having exceedingly high trait values. The TSG2 and TSG3 groups are characterized by low and medium trait values. Hence, it is suggested to select suitable species from these groups, particularly the lesser known high-quality species in afforestation and reforestation programs to meet future timber demand in Bangladesh. 相似文献
44.
Sanjay Gairola Arvind Bhatt Yanadayalan Govender Himansu Baijnath Şerban Procheş Syd Ramdhani 《Urban Forestry & Urban Greening》2013,12(3):315-322
Relatively few studies have investigated mistletoe infestation of tree species in urban settings, and even fewer considered infestation of alien tree species. Here, mistletoe infestation incidence and intensity were studied in Durban, South Africa. The relationship of infestation to tree CBH and height was examined in detail for the mistletoe species Erianthemum dregei. Although E. dregei is known to have a wide range of host taxa, we report E. dregei infestation on 27 new host species for the first time. E. dregei occurred on 30 host species with a preference for the alien host tree Melia azedarach in our study area. The relationship between infestation and CBH indicated that the trees (irrespective of species) of ≥200 cm were more susceptible to the mistletoe attack. The implications of this pattern, as well as those of high host diversity and especially of infestation of alien trees are discussed in a conservation perspective. 相似文献
45.
Arun Prasad Sanjay Kumar Ankit Pandey Sukhmal Chand 《Biology and Fertility of Soils》2012,48(1):117-122
Rose-scented geranium (Pelargonium sp.) is a highly valued aromatic crop. Its growth is limited by soil salinity and sodicity stress. Arbuscular mycorrhizal
(AM) fungus, phosphate-solubilizing bacteria (PSB), and P fertilizers may enhance the growth and secondary metabolism in geranium
plants. In this context, a pot experiment was conducted to study the effects of PSB, AM fungi (Glomus intraradices), and P fertilizer on the yield, chemical composition of essential oil, and mineral element acquisition of geranium. The
dry matter yield of shoot and essential oil yield, and mineral element (P, K, Ca, Mg, Na, Fe, Cu, and Zn) uptake in shoot
tissues of geranium were significantly increased by the inoculation with AM fungi, co-inoculation with AM fungi and PSB, and
P fertilization as compared to control. While the co-inoculation of geranium with AM fungi and PSB significantly enhanced
the content of the monoterpenes such as citronellol, geraniol, geranial, and a sesquiterpene (10-epi-γ eudesmol), the P fertilization only enhanced the content of a sesquiterpene, 10-epi-γ eudesmol in the volatile oil. We conclude that the co-inoculation of PSB and AM fungi could be the best natural alternative
to phosphate fertilizers to enhance the yield and quality of essential oil from geranium plants grown in sodic soils. 相似文献
46.
Wani AA Rewal HS Sahoo S Singh B Bhat JA 《Pakistan journal of biological sciences: PJBS》2012,15(1):44-48
The persistence of fungicides on two commercial cultivars of potato was determined under field conditions at Punjab Agricultural University, Ludhiana, Punjab. Initial deposits of mancozeb on potato leaves were found to be 26.9 and 38.7 mg kg(-1), following application of ready mixture of fungicide metalaxyl 8% + mancozeb 64% (Ridomil MZ) at the rate of 1260 and 2520 g a.i. ha(-1), whereas metalaxyl residues were found to be 35.1 and 49.5 mg kg(-1), respectively. The residue level of mancozeb in potato leaves 15 days after application at single and double doze were 19.0 and 27.0 mg kg(-1) showing a loss of 29.6 and 30.3%, whereas the values for metalaxyl at single and double doze were 0.40 and 0.80 mg kg(-1) showing a loss of 98.9 and 98.4%, respectively. Residues of mancozeb and metalaxyl were not detected at 0.04 and 0.02 mg kg(-1) level in potato tubers at harvest (PHI = 53 days) at both the dosages, respectively. The persistence and dissipation of mancozeb with the application of Ridomil MZ followed similar trend as in Indofil M-45. The rate of fungicide dissipation increased with time after application in both the potato cultivars 'Kufri Chandramukhi' and 'Chipsona'. No significant difference was observed on initial deposit, persistence and dissipation of the two molecules between the two potato cultivars. 相似文献
47.
Kanitz W Bhojwani S Becker F Schneider F 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(11-12):512-515
The objective of the experiment was to study follicular dynamics and characteristics of ovulations in dairy heifers after application of the Ovsynch protocol in the last third of estrous cycle. Therefore, altogether 27 regular cycling Holstein heifers were given an injection of GnRH on day 14, 16 or 18 (9 heifers each in group 1 to 3) of the estrous cycle. All heifers were administered PGF2alpha seven days later. Blood was collected for progesterone determination, just before, 24 hours and 48 hours after the PGF2alpha injection. A second injection of GnRH was administered 48 hours after the PGF2alpha injection. Ovarian follicular dynamics were monitored by frequent ultrasound scanning of the ovaries after first and second GnRH injection. Altogether 22 of 27 heifers (81.5%) ovulated 27 to 33 h after first GnRH injection. In 4 heifers ovulations were recorded 45 to 51 h after first GnRH application. Mean intervals between GnRH application and ovulation were 33.0, 33.6 and 28.3 h, respectively. At the time of PGF2alpha injection mean progesterone concentrations were similar in groups 1 and 2, but significantly lower than in group 3. After the second GnRH treatment 5,6 and 8 heifers had ovulations.The average intervals from the second GnRH treatment to ovulation were 24.8, 24.0 and 24.4 h respectively.The results show that Ovsynch is not sufficient to ensure synchronisation of oestrous and ovulation in each animal treated. 相似文献
48.
Singh K Rani A Kumar S Sood P Mahajan M Yadav SK Singh B Ahuja PS 《Tree physiology》2008,28(9):1349-1356
Tea (Camellia sinensis (L.) O. Kuntze) leaves are a major source of flavonoids that mainly belong to the flavan 3-ols or catechins. Apart from being responsible for tea quality, these compounds have medicinal properties. Flavanone 3-hydroxylase (F3H) is an abundant enzyme in tea leaves that catalyzes the stereospecific hydroxylation of (2S)-naringenin to form (2R,3R)-dihydrokaempferol. We report a full-length cDNA sequence of F3H from tea (CsF3H Accession no. AY641730). CsF3H comprised 1365 bp with an open reading frame of 1107 nt (from 43 to 1149) encoding a polypeptide of 368 amino acids. Expression of CsF3H in an expression vector in Escherichia coli yielded a functional protein with a specific activity of 32 nmol min(-1) mg protein(-1). There was a positive correlation between the concentration of catechins and CsF3H expression in leaves of different developmental stages. CsF3H expression was down-regulated in response to drought, abscisic acid and gibberellic acid treatment, but up-regulated in response to wounding. The concentration of catechins paralleled the expression data. Exposure of tea shoots to 50-100 microM catechins led to down-regulation of CsF3H expression suggesting substrate mediated feedback regulation of the gene. The strong correlation between the concentration of catechins and CsF3H expression indicates a critical role of F3H in catechin biosynthesis. 相似文献
49.
Sanjay K. Sharma Ankita Sharma Surinder Rana Naveen Kumar 《Journal of plant nutrition》2018,41(6):782-792
Sixty soil samples (0–0.15 m depth) collected randomly from different districts of Himachal Pradesh were used to evaluate ammonium bicarbonate-diethylenetriaminepenta acetic acid (AB-DTPA) and acid ammonium acetate-ethylene diamine tetra acetic acid (AAAc-EDTA) over standard methods for P, K, and micronutrient cations. Among Olsen P, Bray P1, AB-DTPA P, and AAAc-EDTA P, available P (kg ha?1) varied from 7.8 to 44.3, 9.5 to 61.1, 6.5 to 38.8, 10.5 to 52.1; available K (kg ha?1) among NH4OAc, AB-DTPA, and AAAc-EDTA ranged from 103.6 to 372.3, 86.6 to 364.9, and 74.6 to 362.5. In case of micronutrients cations, AB-DTPA in general, extracted more amounts as compared to DTPA alone. AAAc-EDTA correlated highly with the Olsen P. AB-DTPA-K and AAAc-EDTA-K correlated well with standard method (NH4OAc) however; AAAc-EDTA had higher correlation with AB-DTPA for K extractability. Among methods for micronutrients highest significant correlations were observed between AB-DTPA and DTPA for Cu, Fe, and Zn. 相似文献
50.
One of the major applications of plant tissue culture technology is that the regenerants are genetically identical to the
mother plant. Although, of the various methods of in vitro propagation, axillary branching method is regarded as the safest,
the possibility of genetic variation (somaclonal variation) cannot be ruled out even in this method. In the present study,
inter simple sequence repeat (ISSR) marker assay was employed to validate the clonal fidelity of in vitro raised Bambusa balcooa plantlets multiplied by enhanced axillary proliferation up to 33 passages. Fifteen ISSR primers generated a total of 99 amplicons
among the tissue-cultured progenies. Analysis of ISSR patterns revealed that the bands were shared by both the parent clump
and the in vitro raised plants confirming the genetic stability in the latter. 相似文献