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51.
Tariq Aziz Iftikhar Ahmed Muhammad Farooq M. Aamer Maqsood Muhammad Sabir 《Journal of plant nutrition》2013,36(13):2006-2017
Plants have adapted a number of mechanisms to cope with widespread phosphorus (P) deficiency in arable lands. Crop species and even cultivars differ widely in one or more of these adaptive mechanisms hence, in P efficiency. Identification of these mechanisms is pre-requisite for long term breeding programs. Two independent experiments were conducted to study the possible mechanisms of P efficiency in Brassica cultivars. Eight Brassica cultivars (‘B.S.A.’, ‘Toria’, ‘Toria Selection’, ‘Brown Raya’, ‘Peela Raya’, ‘Dunkeld’, ‘Rainbow’, and ‘CON-1’) were selected on the basis of differences in growth under P deficiency from preliminary experiment. In the first experiment, cultivars were grown for 40 days in sand supplied either with sparingly soluble phosphate rock (PR) or soluble mono-ammonium phosphate (MAP). Cultivars differed significantly (P<0.05) for biomass production, P contents and P use efficiency. Low P availability in PR treatment resulted in significantly lower dry weights and P contents than those grown with MAP. The cultivars ‘Rainbow’, ‘Brown Raya’ and ‘Dunkeld’ accumulated more biomass (3.2 g/pot) and P contents (3.0 mg/pot) than other cultivars when grown with PR. Root dry weight was significantly correlated with shoot dry weight, shoot P content and total P content (r > 0.65) indicating significance of improved root growth for P acquisition. While in the second experiment cultivars were grown with adequate P for 30 days and then P was withdrawn from the nutrient solution by replacing fresh P free nutrient solution for 10 days. Induced P deficiency increased P contents in young leaves by two folds indicating remobilization of P from older leaves and shoot. Nonetheless cultivars varied for remobilization but differences in P remobilization could not explain the differences in P utilization efficiency among cultivars. Hence further experimentation to study root morphology, P uptake, and organic acid exudation by these cultivars in relation to P deficiency is recommended. 相似文献
52.
Sajid Masood Tayyaba Naz M. Tariq Javed Ijaz Ahmed Habib Ullah Muhammad Iqbal 《Archives of Agronomy and Soil Science》2013,59(3):337-347
Farmyard manure (FYM) improves various soil parameters and to a large extent, the availability of water and nutrient to crops when it is applied to the soil. This study aims to further investigate the short-term effects of different levels of FYM on maize plants and soil parameters. Maize plants grown in pot culture were treated with no FYM (control), recommended NPK (inorganic fertilizers), and FYM at 2, 4, 6, 8, and 10 t ha?1 along with recommended NPK, and the cultures were analyzed 8 weeks after germination. Soil bulk density and soil pH decreased with the increasing levels of FYM, whereas soil porosity, soil organic matter (SOM), soil water content, plant height, root and shoot yield, and NPK uptake of maize were increased compared with the control or recommended NPK, respectively. The present results indicate that short-term application of higher FYM levels improves soil properties. Furthermore, the application of FYM at only higher rates significantly increases the nutrient uptake of maize plants due to improved soil properties. The supply of different amounts of nutrients increases biomass and nutrient uptake in plants. 相似文献
53.
Model-Based Evaluation of Maturity Type of Potato Using a Diverse Set of Standard Cultivars and a Segregating Diploid Population 总被引:2,自引:0,他引:2
The objective of this paper is to evaluate the performance of the conventional system of classifying maturity type in potato and to provide a concept of maturity type based on crop physiology. We present an approach in which physiological traits are used to quantify and assess maturity type unambiguously for a set of varieties covering a wide range of maturity classes and a diploid F1 population separating for maturity and well-adapted to Dutch growing conditions, both grown in six environments. We defined physiological maturity based on four traits: the duration of maximum green canopy, the area under the green canopy cover progress curve, and the rate and duration of tuber bulking. The results indicated that physiological maturity type criteria tended to define maturity classes less ambiguously than the conventional criterion. Moreover, the conventional criterion was subject to more random noise and lacked stability and/or repeatability compared with the physiological traits. The physiological maturity criteria also illustrated the physiological trade-offs that existed between the selected traits and underlined the subtle complexities in classifying maturity type. This study highlighted the capabilities of different maturity type criteria in discriminating between different maturity classes among the large set of genotypes. Our new approach involving key physiological traits could be beneficial in offering physiology-based criteria to re-define maturity type. An improved criterion based on important physiological traits would allow relating the maturity to crop phenology and physiology. These new criteria may be amenable to further genetic analysis and could help in designing strategies for potato ideotype breeding for genotypes with specific maturity types. 相似文献
54.
Riaz Hussain Muhammad Tariq Javed Ahrar Khan Ghulam Muhammad 《Tropical animal health and production》2013,45(8):1723-1729
The present study was carried to ascertain the association of various risk factors of mastitis in water buffaloes. The milk samples from buffaloes were collected and screened through California Mastitis Test for the presence of mastitis. In the present study, 15.2 % prevalence of subclinical mastitis was recorded both at the government (13.4 %) and private farms (15.5 %). The chi-square analysis showed significantly higher involvement of the right rear and front quarters. The analysis of variance technique showed significant difference in live body weight, milk yield, teat end to floor distance (P?<?0.001), udder depth, teat length, and teat diameter in mastitic and healthy buffaloes. The frequency analysis also revealed significant difference between various groups including lactation stage, teat and/or udder pathology, teat shape, and udder shape (P?<?0.001). The logistic regression analysis revealed significant positive association of mastitis with milk leakage, live body weight, milk yield, parity, calf suckling, pendulous udder, number of attendants at the farm, dirty hind legs, and udder depth. 相似文献
55.
Abstract Large scale field trials were undertaken with emulsifiable concentrates of different organophosphorus insecticides to control Pyrilla and whitefly, two serious pests of the sugarcane crop in the Peshawar Division of West Pakistan. All emulsifiable concentrates excepting Dimecron were applied in concentrate form without diluting with water. Of the seven insecticides tested against Pyrilla adults and nymphs, Dimecron, Lebaycid, Nexion (Bromophos) and Malathion gave superior control. In the case of whitefly, Dimecron, Lebaycid and Malathion gave almost equal mortality of adults and 3rd instar nymphs when applied at 8, 8 and 17 oz a.i./ac respectively, but much higher dosages would be required to get satisfactory control of the 4th instar nymphs. The cost of operations for the ultra-low-volume technique (excluding cost of insecticide) was 66% less than for the conventional method. 相似文献
56.
PET fabric is coated with conducting polypyrrole (PPy) by oxidative polymerization from an aqueous solution of Py using ferric
chloride hexahydrate (FeCl3) as oxidant and p-toluene sulphonate (pTSA) as dopant. The optimum concentrations for Py, FeCl3 and pTSA were found to be 0.11, 0.857 and 0.077 mol/l respectively, which yielded a conductive fabrics with resistivity as
low as 72 Ω/sq. PPy fabric gained resistivity less than one order of magnitude when aged for 18 months at room temperature.
The stabilizing effect of the dopant pTSA against thermal degradation was demonstrated; the undoped samples reached resistivity
of around 40 kΩ, whereas doped samples reached less than 2 kΩ at the same temperature and time. 相似文献
57.
Tariq M. Butt Martyn Wood James W. D. Taylor Serkan Bakirci Canan Hazir Derya Ulug 《国际虫害防治杂志》2016,62(3):261-266
This study investigated the virulence of the entomopathogenic fungus, Metarhizium anisopliae strain ARSEF 4556, and the entomopathogenic nematode Steinernema carpocapsae against adult and nymphal stages of the tick Hyalomma anatolicum excavatum. The fungus was tested at three different concentrations, 106, 107, and 108 conidia ml?1. Ticks were exposed to 4000 IJs of S. carpocapsae in 0.5 ml distilled water in Petri dishes lined with 2 layers of moist filter paper. Adult ticks were not susceptible to M. anisopliae, whereas the nymphs were highly susceptible. Nymph mortality was dose dependent with all ticks being killed at the highest dose 96 hours post-inoculation. In contrast, S. carpocapsae was much more effective against engorged adults than unfed adults or nymphs. Tick susceptibility was not influenced by gender. The mean mortalities of the unfed adult males, females, and nymphs were 30% ± 9.2%, 40% ± 7.5%, and 36% ± 4.7%, respectively. Nymphal mortality was 36% and there was a significant difference between nematode treatment and control group (P < 0.05). 相似文献
58.
Qasim Ali Muhammad Tariq Javed Ali Noman Muhammad Zulqarnain Haider Muhammad Waseem Naeem Iqbal 《Archives of Agronomy and Soil Science》2018,64(1):84-102
Drought stress hampers firm crop stand establishment and yield in arid and semiarid regions. The present study was conducted to examine the drought tolerance of various mung bean cultivars/lines based on the seed germination characteristics in relation with the seedling’s antioxidative potential and nutrient uptake. Activities of germination enzymes, seed germination attributes, seedling biomass production and nutrient uptake of studied cultivars/lines were adversely affected due to PEG-induced drought but the total soluble proteins (TSP) and malondialdehyde (MDA) contents were increased. The activities of catalse (CAT) and ascorbate peroxidase (APX) increased in all cultivars/lines being the maximum in cv./line NM-2006 and 8005. The activities of superoxide dismutase (SOD) and peroxidase (POD) were increased in cv./line NM-2006 and 8005 under drought condition. The ascorbic acid (AsA) and total phenolic content (TPC) decreased and total flavonoid content (TFC) increased in all cultivars/lines due to drought. Significant reduction in N, P, K, Ca and Mg was found in all cvs./lines but Fe remain unchanged. In conclusion, cultivars/lines NM-2006, 8005 were recommended as drought tolerant and 97,006 and 97,001 as drought sensitive ones. The study outcomes will likely be helpful for the farmers growing mung bean in rain fed areas for the better productivity. 相似文献
59.
Kylie D. Swisher Grimm Tariq Mustafa W. Rodney Cooper Joseph E. Munyaneza 《American Journal of Potato Research》2018,95(6):709-719
Two haplotypes of the pathogen, ‘Candidatus Liberibacter solanacearum,’ (Lso) and four haplotypes of the insect vector, Bactericera cockerelli, are associated with zebra chip disease of potato. Whether disease severity or incidence is influenced by pathogen or insect haplotype is poorly understood. The role of Lso ‘A’ and ‘B,’ transmitted by three haplotypes of B. cockerelli, on disease severity and incidence in eight potato cultivars was analyzed. Both haplotypes of Lso induced tuber symptoms. In general, Lso B caused higher incidence of symptoms, and greater reduction in tubers compared with Lso A. Lso B was associated with more severe tuber symptoms, producing fewer mild or moderate tuber symptoms. Lso A was associated with less severe tuber symptoms, despite being able to induce severe symptoms. Disease incidence, tuber yield, and symptom severity ratings were not dependent upon the psyllid haplotype transmitting the pathogen, suggesting that pathogen, not insect haplotype affects Lso transmission. 相似文献
60.
Asad M. F. AlKhader Muien M. Qaryouti Tariq Yousef Mohammed Okasheh 《Journal of plant nutrition》2019,42(7):737-748
A two-year field experiment was conducted during the growing seasons 2016 and 2017 to investigate the response of drip fertigated watermelon to different rates of nitrogen (0, 10, 20, 30, and 40?g/m3 N) applied in the form of ammonium sulfate (AS). The combined effect of nitrogen (N) and sulfur (S) was investigated. Irrigation water use efficiency (IWUE) under the different N levels was, also, evaluated. N levels in the irrigation water induced a significant effect on yield parameters (total and commercial yields, dry matter yield, plant yield, and fruit number). Increasing the level of N also induced significant increases in fruit length and fruit fresh weight. IWUE was also significantly improved at high levels of N. Fertigation using modern techniques can be considered an efficient method in the delivery of N to the crop at N levels of 30–40?g/m3, as ammonium sulfate. 相似文献