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61.
Yield and nitrogen (N)-content in wheat was studied under applied treatments of crop residues (legume vs. cereal), tillage depths (deep vs. shallow) and N-fertilizer rates (0, 40, 80, 120 and 160 kg ha?1) at wheat-maize cropping systems. Experiments were conducted at Agronomy Research farm, the University of Agriculture, Peshawar Pakistan, during winter season 2009–2010 and 2010–2011 crop growth seasons. Well-chopped crop residues (5 t ha?1) on dry matter basis of legume (Vigna unguicuata) and cereal (Zea mays) were applied to soil and subsequently plowed with mold-board plow as deep tillage (DT) and cultivator as shallow tillage (ST) treatment (main plot treatments). A month after residue and tillage application, seedbed was prepared and wheat was planted with drill in rows 25 cm apart in middle of November each year. Phosphorus and potassium were applied uniformly 80 and 40 kg ha?1, respectively during seedbed preparation. N-fertilizer rates were applied in two splits: half 15 days after sowing (DAS) and other half 45 DAS (sub-plot treatment). Uniform cultural practices were applied during crop growth and development. Legumes residues amendments showed better responses than cereal but lower than no-residue treatment for N-content in leaf blade before anthesis (LBA), after anthesis (LAA), straw N-content (SNC), grain N-content (GNC), grain N-uptake (GNU), crop N-removal (CNR), recovery efficiency of added nitrogen (REAN), N-use efficiency (NUE), grain N-uptake (GNU) and grain yield. Likewise, shallow tillage proved better than deep tillage system for LBA, LAA, SNC, GNC, GNU, CNR, REAN, NUE, GNU and grain yield. Increased N-fertilizer from control onwards showed significant (p > 0.05) increments in LBA, LAA, SNC, GNC, GNU, CNR, N-uptake and grain yield. Treatments interaction was also found significant (p > 0.05). Study suggested, regardless of the given treatments, GNU and grain yield were in strong positive linear relationship. Legume residue incorporated shallow out yielded GNU and NUE of spring wheat in wheat-maize cropping system. It is concluded that LR and ST with 120 kg N ha?1 ensures production of good wheat quantity and quality. 相似文献
62.
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
63.
R. K. Naresh R. S. Rathore S. S. Dhaliwal R. B. Yadav Dipender Kumar S. P. Singh Adil Nawaz Narendra Kumar Raj K. Gupta 《Paddy and Water Environment》2016,14(3):373-386
A 3-year field experiment was carried out with tillage crop establishment (TCE) and rice nourishment in north-western India to evaluate the effect of five crop establishment methods and seven fertility treatments on crop production, water productivity, profitability, and soil physical quality. Maximum panicle length (30.9 cm) was noted with F3 treatment and minimum (22.7 cm) with F0 treatment. Zinc application methods and timing had significantly effect on paddy yield. Maximum yield (5.22 t ha?1) was achieved in treatment F3 and minimum yield (2.65 t ha?1) was noted in F0 treatment. Results also revealed that root dry weight, root volume, and root length were recorded with higher values in F3 treatment and minimum in F0 treatment. TCE methods were recorded with higher values in raised beds system than T5 at all growth stages. Treatments T1 and T2 reduced the mean maximum soil temperature at transplanting zone depth by 3.6 and 2.7 °C compared to the T3. Paddy yield in T3 was always significantly less than in T5. On average, treatment T4 recorded about 13 % lower water use and 3.7 % higher water productivity compared to T5. Treatment T5 had higher bulk density. The cumulative infiltration for 498 min was about 2 times in treatment T1, 5 times in T3 and more than 8 times in T4 of the values in T5. Mean weight diameter of aggregates was higher in T4 followed by the T1 and lowest in T5. The study reveals that TCE methods T1 and T4 with F3 nourishment could be more viable options for rice crop in order to save input costs and enhance profitability. 相似文献
64.
Mubshar Hussain Muhammad Farooq Ahmad Nawaz Abdullah M. Al-Sadi Zakaria M. Solaiman Salem S. Alghamdi Ume Ammara Yong Sik Ok Kadambot H. M. Siddique 《Journal of Soils and Sediments》2017,17(3):685-716
Purpose
Biochar, the by-product of thermal decomposition of organic materials in an oxygen-limited environment, is increasingly being investigated due to its potential benefits for soil health, crop yield, carbon (C) sequestration, and greenhouse gas (GHG) mitigation.Materials and methods
In this review, we discuss the potential role of biochar for improving crop yields and decreasing the emission of greenhouse gases, along with the potential risks involved with biochar application and strategies to avoid these risks.Results and discussion
Biochar soil amendment improves crop productivity mainly by increasing nutrient use efficiency and water holding capacity. However, improvements to crop production are often recorded in highly degraded and nutrient-poor soils, while its application to fertile and healthy soils does not always increase crop yield. Since biochars are produced from a variety of feedstocks, certain contaminants can be present. Heavy metals in biochar may affect plant growth as well as rhizosphere microbial and faunal communities and functions. Biochar manufacturers should get certification that their products meet International Biochar Initiative (IBI) quality standards (basic utility properties, toxicant assessment, advanced analysis, and soil enhancement properties).Conclusions
The long-term effects of biochar on soil functions and its fate in different soil types require immediate attention. Biochar may change the soil biological community composition and abundance and retain the pesticides applied. As a consequence, weed control in biochar-amended soils may be difficult as preemergence herbicides may become less effective.65.
Muhammad Asif Shehzad Muhammad Maqsood Fahim Nawaz Tasawer Abbas Sanaullah Yasin 《Journal of plant nutrition》2018,41(8):943-955
Terminal drought stress (drought at reproductive growth stage) has been considered a severe environmental threat under changing climatic scenarios and undoubtedly inhibits sunflower production. A field study was conducted to explore the potential role of foliar applied boron (B) (0, 15, 30, 45 mg L?1) at late growth periods of sunflower in alleviating the adversities of terminal drought stress (75, 64, 53 mm DI) grown from inflorescence emergence to maturity stages. The plant water relations such as leaf relative water content (RWC), water potential (Ψw), osmotic potential (Ψs), and turgor pressure (Ψp) were increased significantly with B foliar sprays while exposed to terminal drought stress. Foliar B application considerably improved the nitrogen and B concentrations in leaf and seed tissues, and also chlorophyll a and b pigments under terminal drought stress conditions. Drought-induced proline accumulation prevented the damages caused by drought stress, nevertheless, B foliar spray increased its contents. Compared to well-watered conditions, terminal drought stress substantially declined the growth performance in terms of reduced leaf area index (LAI), crop growth rate (CGR), net assimilation rate (NAR), and total dry matter (TDM) production; however, foliar B supply (30 mg L?1) might be helpful for improving drought tolerance in sunflower with reduced growth losses. 相似文献
66.
Asad Shabbir Kunjithapatham Dhileepan Myron Zalucki Naeem Khan Steve Adkins 《Archives of Agronomy and Soil Science》2018,64(13):1861-1878
Parthenium weed (Parthenium hysterophorus L.; Asteraceae) is an invasive weed species in agro-ecosystems. It causes huge losses to native biodiversity and agricultural productivity. This study was conducted to assess the combined effect of a leaf-feeding beetle, (Zygogramma bicolorata Pallister; Chrysomelidae) and suppressive plant species, bull Mitchell grass (Astrebella squrossa C.E. Hubb.; Poaceae) or butterfly pea (Clitoria ternatea L.; Fabaceae) on parthenium weed under shade house conditions. The suppressive plant species significantly reduced the parthenium weed height (16%), biomass (29%) and seed production (42%), in the absence of Z. bicolorata. However, this suppressive ability was further enhanced in the presence of Z. bicolorata. The combined effect of the suppressive plant species and Z. bicolorata further reduced the parthenium weed height (46%), biomass (66%) and seed production (95%). The combination also had a significant negative effect upon seed fill, decreasing the reproductive output of the current generation. The presence of Z. bicolorata also had positive effect on the biomass (10%) and plant height (11%) of both suppressive species. So, the combined use of suppressive plant species and the biological control agent suppressed parthenium weed more effectively than their sole use. Such integrated approaches should be prioritized for future management of parthenium weed. 相似文献
67.
68.
Deosai Plateau in Northern Pakistan was designated a national park to protect the largest remnant population of brown bears in Pakistan. The natural resources of this high elevation (3500-5000 m) park make a significant contribution to the livelihood of local and nomad communities. The present legislation excludes people from a park, which increases conflicts between management and local people. However, a pragmatic approach was adopted to involve people in conservation in Deosai. Community participation, achieved by recognizing rights and introducing incentives, reduced resistance against the conservation efforts, reduced grazing pressure in bear habitat and helped reduce poaching. The size of the brown bear population was set as an indicator of park success, and was monitored annually from 1993 through 2006. We observed a 5% annual growth of the brown bear population, suggesting that the conservation program has been successful due to a successful cooperation between an NGO, people, and the park management.The increase of the bear population is significant, because we observed an extremely low reproductive rate, due to late age of first reproduction (8.25 years), a long reproductive interval (5.7 years), and a small litter size (1.33). The reproductive rate of the Deosai population is the lowest yet documented for brown bear populations. Poor habitat quality, low quality food, high seasonality, and extreme weather conditions in the Himalaya probably explain the poor reproductive performance. Considering such low reproduction and known exchange of individuals with neighboring populations, we believe that the observed growth was a sum of reproduction and immigration. Brown bears are declining throughout South Asia and often have low-productive rates. Therefore, conservation efforts for brown bears in this region must target reducing human-caused mortalities, particularly of adult females. Involvement of people can increase efficiency in conservation, in addition to reducing cost and conflicts. 相似文献
69.
Ahmad Sher Abdul Sattar Abdul Qayyum Muhammad Ijaz Ahmad Nawaz Abdul Manaf 《Journal of plant nutrition》2019,42(13):1556-1565
The production of oil from the conventional oilseed seed crops (viz. mustard, rapeseed) is not sufficient to meet the demands of Pakistani people. Due to this reason, a surplus quantity of oil is imported every year from different countries to fulfill the domestic demands of the cooking oil. This 2-year study was aimed to optimize the dose of NPK for profitable production of white mustard. Nitrogen (0, 60, 90?kg ha?1), phosphorous (0, 30, 60?kg ha?1) and potassium (0, 75, 100?kg ha?1) were applied in various combinations. The results indicated that highest seed yield and profitability was recorded with NPK at 90–60–100?kg ha?1, which was attributed to improvement in crop growth. In crux, application of NPK at pre-optimized rate might be a viable option to improve the growth, yield, oil quality, and economics of white mustard production under arid climates in Pakistan. According to the results, a balanced use of NPK fertilization is a key management strategy for white mustard growing farmers of arid region. 相似文献
70.
M Nawaz 《Nordisk veterinaermedicin》1979,31(3):129-136
The pharmacokinetics studies in 48 experiments on the animals of different ages showed that the half-life of CPZ in kids (new born, 1 week and 3 weeks old) and goats (3 months old and adult animals) ranged from 1.47 to 1.86 hour while distribution half-life was only 0.11 to 0.17 hour. Volume of distribution of CPZ in kids and goats was much higher than 1 which indicated that the drug was extensively localized in the tissues. The elimination of CPZ was more rapid in the adult goats than in the kids. The half-life of CPZ was short and elimination was rapid in the goats as compared to the literature values for man, rat and dog. The differences are attributed primarily to the more rapid metabolism of CPZ in the goats than in the kids or man, rat and dog. 相似文献