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111.
Wheat cultivars (‘AC Barrie’, ‘Brook Field’, ‘Hoffman’, and ‘Norwell’) with different protein concentrations were compared under four nitrogen (N) levels (0, 50, 100 and 150 kg ha?1) in an environment-controlled greenhouse, and the same experiment with an additional N level (200 kg N ha?1) was repeated in the field in 2007. In the greenhouse experiment, application of 100 kg N ha?1 resulted in significantly greater grain yield due mainly to higher number of grains per spike and heavier mean grain weight; in the field study, the 150 kg N ha?1 treatment produced the greatest yield (P<0.01) primarily due to more number of grains per spike. Crude grain protein percentage was increased significantly with each increment of N up to the highest level; however, protein yield (kg ha?1) increased significantly with fertilizer up to 150 kg N ha?1. Leaf chlorophyll contents were increased linearly with increment of N levels up to 150 kg ha?1 both in the greenhouse and field trials while leaf area indices continued to increase up to the highest application rate (200 kg N ha?1). Canopy reflectance, expressed as normalized difference vegetation index (NDVI), attained maximum value with 150 kg N ha?1 in the field experiment. Among the varieties tested, “Hoffman” out-yielded other three varieties due to heavier grain weight. Although highest grain and/or plant crude protein content were recorded in ‘AC Barrie’, it was the variety ‘Hoffman’ that produced the highest total protein (kg ha?1) with largest NDVI and leaf area index (LAI) values. 相似文献
112.
S. Ullah A. S. Khan A. U. Malik I. Afzal M. Shahid K. Razzaq 《Journal of plant nutrition》2013,36(13):2067-2079
The effects of foliar application of boron (B) in the form of boric acid on vegetative and reproductive growth, yield and fruit quality of ‘Kinnow’ mandarin (Citrus reticulate Blanco.) were investigated. Kinnow mandarin was sprayed with different concentrations of boric acid viz. (0.1%, 0.2%, 0.3% and 0.4%) at fruit set stage. Leaf nitrogen (N), phosphorus (P), potassium (K), B, and zinc (Zn) along with flush length, tree height, tree spread and tree trunk diameter increased, while leaf length and leaf age showed non-significant results after foliar B application. Yield of the ‘Kinnow’ mandarin was significantly affected by foliar application of B and a significant increase in fruit weight at harvest was also observed. Soluble solid concentration (SSC): titratable acidity (TA) ratio, ascorbic acid, total sugars, total phenolic content (TPC) and total antioxidants significantly affected, while pH of juice, SSC, TA, reducing sugars and non-reducing sugars showed non- significant results. 相似文献
113.
Muhammad Asif Naeem Shahid Hussain Muhammad Khawar Khan Shamsa Kanwal 《Archives of Agronomy and Soil Science》2013,59(1):133-145
The boron (B) sufficiency range for plant growth is narrow and its management is problematic under brackish irrigation water. This study was conducted to evaluate the B requirement of mungbean at different sodium adsorption ratios of irrigation waters (SARiw) [control, 8 and 16 (mmolc L?1)1/2]. The boron adsorption characteristics of a loamy soil were first determined in the laboratory by equilibrating 2.5 g soil with 0.01 M CaCl2 solution containing different B levels. Boron rates for a pot study were computed against different soil solution levels by fitting sorption data in a modified Freundlich model [x/m = K f (EBC)1/n ]. The maximum increase in shoot dry matter was 11.9% when B was applied at 1.29 mg kg?1 soil at control SARiw. Visual leaf B toxicity symptoms appeared at higher B rates and became severe at higher SARiw. By contrast to Ca, shoot concentrations of B and Na increased significantly with B application and SARiw. For optimum shoot growth, internal and external B requirements were 25 mg B kg?1 shoot dry matter and 0.39 mg B L?1 soil solution, respectively, at control SARiw. At higher SARiw, a lower concentration of B in plant shoots and soil solution had an inhibitory effect on plant growth. 相似文献
114.
Tripathi Rahul Nayak Amaresh Kumar Dhal Biswaranjan Shahid Mohammad Lal Banwari Gautam Priyanka 《Archives of Agronomy and Soil Science》2013,59(13):1775-1787
ABSTRACTThe present study was to delineate management zones (MZs) in salt affected Mahakalpada block in eastern India by capturing both spatial variability of soil parameters along with satellite derived Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). Grid wise 237 soil samples collected from the study area were analyzed and spatial maps were generated for physicochemical properties, DTPA extractable micronutrients, i.e. iron, zinc, copper, and manganese and major nutrients, i.e. available nitrogen (AN), phosphorous (AP), and potassium (AK). Soil electrical conductivity and AK showed a high CV of 100% and 56.7%, respectively. Principal component analysis was performed using the soil spatial maps, NDVI and EVI maps and only four principal components which produced eigenvalues > 1 and accounting for 75.4% of the total variability were retained for further analysis. Further, fuzzy c-mean clustering was used to delineate the MZs based on fuzzy performance index (FPI) and normalized classification entropy (NCE) was used for identifying the three MZs. There was a significant difference between MZ1 and MZ2 for all the variables except AN and EVI whereas all the variables were significantly different between MZ1 and MZ3 highlighting the usefulness of MZs delineation technique for site-specific nutrient management. 相似文献
115.
Isolation and antioxidative properties of phenolics-saponins rich fraction from defatted rice bran 总被引:1,自引:0,他引:1
The study presents a protocol for the preparation of phenolics-saponins rich fraction (PSRF), a new active nutraceutical from defatted rice bran followed by the determination of its antioxidant properties. PSRF was prepared by employing a simple alcoholic fractionation procedure on the crude alcoholic extract (CAE) of defatted rice bran. PSRF was found to be significantly higher in the contents of total phenolic, saponin, and steroidal saponin than CAE and its counterpart, aqueous fraction (AqF) (p < 0.05). Except for iron chelating activity, PSRF exhibited notably higher activity than CAE and AqF in all antioxidant activity assays performed (p < 0.05). HPLC-DAD analysis revealed that PSRF contained substantially higher amounts of gallic acid, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, and ferulic acid than CAE and AqF (p < 0.05). In conclusion, alcoholic fractionation of CAE simultaneously concentrated the phenolic compounds and saponins into PSRF, thus contributed to its higher antioxidant activity. Due to its elevated antioxidant properties, PSRF may be recommended for investigation as an active ingredient in the nutraceutical, functional food, and natural food preservative formulations. This is also the first report suggesting defatted rice bran as a potential and sustainable source of saponins. 相似文献
116.
M.J. Morrison E.R. Cober M.F. Saleem N.B. McLaughlin J. Frégeau-Reid B.L. Ma L. Woodrow 《Field Crops Research》2010
Future soybean [Glycine max (L.) Merr.] cultivars with elevated or reduced concentrations of isoflavones may be required to satisfy the food market. Climate influences isoflavone concentration making their prediction problematic. Our research examined the associations between precipitation and temperature during a growing season with the isoflavone concentration in the harvested seed. We grew 14 cultivars across 12 years, at one location and calculated climate parameters for readily identifiable growth stage intervals (GSI). We correlated the climate parameters within each GSI with seed daidzein, genistein and total isoflavone (TIF) concentrations. We found that cumulative precipitation from the mid-vegetative to the flowering period was correlated with daidzein and TIF concentration. Mean daily average T during early vegetative development was positively correlated with daidzein and TIF concentration and this was largely a result of higher minimum daily T. Accumulated heat stress T greater than 27 °C during seed development was significantly correlated with a reduction in genistein and TIF, but not daidzein concentration. Accumulated cold stress T's less than 20, 15 and 17 °C during seedling emergence were significantly correlated with higher seed daidzein, genistein and TIF concentrations, respectively in all short-season cultivars tested. Cold stress T during seedling emergence could be used to predict seasonal changes in isoflavone concentrations. 相似文献
117.
Zafar Iqbal Sohail Hameed Muhammad Akbar Anjum Altaf Ahmad Dasti Ahmad Saleem 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(3):391-398
Aetiology of mango malformation (MM) has intrigued the scientists since its inception. The objective of the study was to glean
an insight into association of the fungus, Fusarium mangiferae, with different malformed regions, viz. panicle-shoot juncture, apical buds, primary and secondary peduncles, in five exotic
mango cultivars. Tissue assays revealed an infection of 88.5, 84.75 and 82.5% in cvs Zill, Sensation and Tommy Atkins, respectively.
Least infection of 69.75% was found in cv. Keitt. No exotic cultivar was found to be free of fungal infection. Apical buds
proved to be the potential infection site of the fungus amongst the four malformed regions, hosting maximum within-tissue
infection of 86.2%. Determination of F. mangiferae at proximal and distant sites of the malformed panicles exhibited maximum recovery of 82.0% at 0 cm and only 3% at >30 cm
distance beneath the panicle. In the case of non-malformed panicles, an infection of 14.0% was recorded at 0 cm distance while
no detection could be made from non-malformed branches. Moreover, examination of ultra-thin bud sections under Transmission
Electron Microscopy (TEM) revealed inter- and intra-cellular ramification of fungal hyphae, indicating fungal ingress in malformed
bud tissues of local cv. Malda. The present studies explored the sites hosting the causal fungus in mango and provide convincing
evidence that F. mangiferae is responsible for turning healthy tissues into the malformed condition. These findings suggest that inoculum specific management
strategies are needed in future to curb malformation disease in mango orchards. 相似文献
118.
Sohail Irshad Muhammad Ashfaq Wahid Muhammad Farrukh Saleem Shahzad Maqsood Ahmed Basra Muhammad Tariq Saeed 《Journal of plant nutrition》2016,39(6):856-865
Influence of different phosphorus (P) sources on growth, yield and oil quality of linola was evaluated when randomized in complete block design using three replications. Treatments were control (No P), hydropriming, soil phosphorus (50 kg ha?1), seed inoculation with phosphate solubilizing bacteria (PSB, Bacillus spp.) and seed priming with single super phosphate (2%) alone and combined with reduced soil phosphorus (25 kg P ha?1). Among treatments, hydropriming and seed inoculation reduced seedling 50% and mean emergence time with highest emergence index, seedling fresh and dry weights and chlorophyll contents. Seed inoculation with soil P (25 kg ha?1) produced highest seeds per capsule, 100-seed weight, seed and biological yield, harvest index. Maximum oil percentage, low protein contents and high cost benefit ratio with net economic returns were also found for seed inoculation combined with soil phosphorus. Nonetheless, soil phosphorus application can be reduced when seed inoculation with PSB is employed. 相似文献
119.
Muhammad Saleem Kashif Zahid Ata Cheema Ahmad Nawaz 《Archives of Agronomy and Soil Science》2016,62(4):580-592
In this 2-year field study, we investigated the allelopathic effects of three wheat cultivars (Shafaq-06, Faisalabad-08 and Sehar-06) against different density levels (0, 100, 200 and 300 plants m?2) of littleseed canarygrass (Phalaris minor Retz.). Crop was sown on 1 and 3 December during 2010–2011 and 2011–2012 cropping seasons, respectively. The results showed that wheat cultivar Shafaq-06 produced more phenolic compounds at all density levels of littleseed canarygrass during both years, which caused more inhibition of littleseed canarygrass growth. More suppressive advantage of cultivar Shafaq-06 against littleseed canarygrass was responsible for its better morphological and yield related traits, and grain yield than cultivars Faisalabad-08 and Sehar-06. Among the tested cultivars, cultivar Sehar-06 had minimum allelopathic potential in suppressing littleseed canarygrass. In crux, Shafaq-06 possesses allelopathic potential to suppress littleseed canarygrass and may be used for breeding future wheat cultivars with high allelopathic activity for better weed suppression. 相似文献
120.
Muhammad Saleem ARIF Muhammad RIAZ Sher Muhammad SHAHZAD Tahira YASMEEN Shafaqat ALI Muhammad Javed AKHTAR 《土壤圈》2017,27(6):1049-1061
Legume plants are an essential component of sustainable farming systems. Phosphorus (P) deficiency is a significant constraint for legume production, especially in nutrient-poor soils of arid and semi-arid regions. In the present study, we conducted a pot experiment to evaluate the effects of a phosphorus-mobilizing plant-growth promoting rhizobacterial strain Bacillus cereus GS6, either alone or combined with phosphate-enriched compost (PEC) on the symbiotic (nodulation-N2 fixation) performance of soybean (Glycine max (L.) Merr.) on an Aridisol. The PEC was produced by composting food waste with addition of single super phosphate. The bacterial strain B. cereus GS6 showed considerable potential for P solubilization and mobilization by releasing carboxylates in insoluble P (rock phosphate)-enriched medium. Inoculation of B. cereus GS6 in combination with PEC application significantly improved nodulation and nodule N2 fixation efficiency. Compared to the control (without B. cereus GS6 and PEC), the combined application of B. cereus GS6 with PEC resulted in significantly higher accumulation of nitrogen (N), P, and potassium (K) in grain, shoot, and nodule. The N:P and P:K ratios in nodules were significantly altered by the application of PEC and B. cereus GS6, which reflected the important roles of P and K in symbiotic performance of soybean. The combined application of PEC and B. cereus GS6 also significantly increased the soil dehydrogenase and phosphomonoesterase activities, as well as the soil available N, P, and K contents. Significant positive relationships were found between soil organic carbon (C) content, dehydrogenase and phosphomonoesterase activities, and available N, P, and K contents. This study suggests that inoculation of P-mobilizing rhizobacteria, such as B. cereus GS6, in combination with PEC application might enhance legume productivity by improving nodulation and nodule N2 fixation efficiency. 相似文献