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71.
Wang Xuemei Xu Kai Miao Wenhao Gao Linhao Ullah Saif Lyu Yueming Wang Xiangping 《European Journal of Forest Research》2022,141(5):927-938
European Journal of Forest Research - Increasing drought associated with climate warming (i.e., hotter drought) is seriously threatening tree growth and survival across the world. Previous studies... 相似文献
72.
Hafeez Abdul Ullah Zia Khan Rifat Ullah Ullah Qudrat Naz Shabana 《Tropical animal health and production》2020,52(5):2499-2504
Tropical Animal Health and Production - The current research study was designed to determine the inclusion of 2% dietary essential coconut oil with and without coccidiosis challenge on... 相似文献
73.
Fasih Ullah HAIDER Jeffrey A. COULTER Liqun CAI Saddam HUSSAIN Sardar Alam CHEEMA Jun WU Renzhi ZHANG 《土壤圈》2022,32(1):107-130
The degradation of soil fertility and quality due to rapid industrialization and human activities has stimulated interest in the rehabilitation of low-fertility soils to sustainably improve crop yield. In this regard, biochar has emerged as an effective multi-beneficial additive that can be used as a medium for the amelioration of soil properties and plant growth. The current review highlights the methods and conditions for biochar production and the effects of pyrolysis temperature, feedstock type, and retention time on the physicochemical properties of biochar. We also discuss the impact of biochar as a soil amendment with respect to enhancing soil physical (e.g., surface area, porosity, ion exchange, and water-holding capacity) and chemical (e.g., pH, nutrient exchange,functional groups, and carbon sequestration) properties, improving the soil microbiome for increased plant nutrient uptake and growth, reducing greenhouse gas emissions, minimizing infectious diseases in plants, and facilitating the remediation of heavy metal-contaminated soils. The possible mechanisms for biochar-induced amelioration of soil and plant characteristics are also described, and we consider the challenges associated with biochar utilization. The findings discussed in this review support the feasibility of expending the application of biochar to improve degraded soils in industrial and saline-alkali regions, thereby increasing the usable amount of cultivated soil. Future research should include long-term field experiments and studies on biochar production and environmental risk management to optimize biochar performance for specific soil remediation purposes. 相似文献
74.
Zahur AB Ullah A Hussain M Irshad H Hameed A Jahangir M Farooq MS 《Preventive veterinary medicine》2011,102(1):87-92
A sero survey was conducted during 2005-2006 to estimate the sero prevalence of PPR in the small ruminant population of Pakistan. A total of 2798 samples were collected including goats (1979) and sheep (819) from villages in 27 randomly selected districts. These were tested by cELISA for PPRV and true prevalence estimates were calculated by Rogan and Gladen estimator. Overall, 1273 (45.5%) were found positive; 980 (49.5%) of 1979 samples from goats and 293 (35.8%) of 819 serum samples from sheep were positive. The true sero-prevalence of PPR was estimated to be 48.5% (95% CI, 46.6-50.3), and 52.9% (95% CI, 50.7-55.1) and 37.7 (95% CI, 34.4-41.0) for goats and sheep, respectively. PPR virus is widely distributed all across Pakistan and has become an endemic infection of small ruminants. Since it is one of the leading causes of morbidity and mortality in small ruminants, it poses a serious threat to food security and the rural economy in Pakistan. 相似文献
75.
Jang Eun-Kyung Ullah Ihsan Kim Min-Sung Lee Kyeong-Yeoll Shin Jae-Ho 《植物病害和植物保护杂志》2011,118(5):178-184
Journal of Plant Diseases and Protection - Entomopathogenic nematodes symbiotically associated with Photorhabdus spp. invade the larvae of susceptible insects and Photorhabdus bacteria are released... 相似文献
76.
不同灌溉技术条件对冬小麦生产的影响 总被引:3,自引:0,他引:3
为了研究并得到3种不同灌溉技术(滴灌、喷灌、漫灌)对冬小麦产量及其构成的影响,在中国农业大学吴桥实验站设计了滴灌、喷灌、漫灌的大田试验.3种灌溉技术条件下,其灌溉总量相同,漫灌和喷灌采用浇底墒水加浇两水,滴灌采用浇底墒水加浇四水的方式;从冬小麦整个生长期内的作物高度、叶面积指数、籽粒重等指标,考察不同灌溉技术对冬小麦生产及其构成的影响.结果表明:滴灌条件下,表层含水量下降速度最小,整个生长期,含水量高于喷灌和漫灌;滴灌处理的叶面积指数最高,其次是喷灌;在成熟期,滴灌条件下,作物高度比漫灌高12%,比喷灌高5%;滴灌和喷灌的条件下产量分别比漫灌高8.63%,7.75%;滴灌、喷灌、漫灌的籽粒千粒重分别为43.36,42.17和41.17 g,滴灌和喷灌籽粒重明显高于漫灌,且生物量分别比漫灌提高了6.9%,3%.这说明3种灌溉技术中,滴灌技术最有利于实现节水保墒、小麦增产,其次是喷灌. 相似文献
77.
Interesting physical models of threads, rouleaux of red blood cells, and other flexible structures (including macromolecules) have been prepared with chains of spheres and discs. When suspended in a viscous liquid undergoing shear flow, the aggregates rotate as nearly rigid bodies, even though they have no tensile strength or stiffness until shear rates high enough to cause bending and then breaking are reached. By adding a second liquid phase which causes a meniscus to bridge adjacent particles, sufficient tensile strength can be provided to cause bending without breakage. 相似文献
78.
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
79.
Optimizing row spacing in wheat cultivars differing in tillering and stature for higher productivity
M. Hussain M.B. Khan Z. Mehmood A.B. Zia K. Jabran 《Archives of Agronomy and Soil Science》2013,59(11):1457-1470
Five wheat cultivars differing in tillering capacity and stature, Sahar-2006 (SH-06) (tall and low tillering), Faisalabad-2008 (FSD-08) (tall and low tillering), Lassani-2008 (LS-08) (medium stature and low tillering), Abdulstar-2002 (AS-02) (medium stature and high tillering) and Triple dwarf-1 (TD-1) (dwarf and low tillering), were planted in 10-, 20- and 30-cm spaced rows in a two-year study with same plant density. Higher grain yield in 20-cm spaced rows during both years and 30-cm spaced rows during the first year of the study in tall and low tillering wheat cultivars was attributed to more productive tillers, grains per spike and 1000-grain weight. However, the higher number of productive tillers resulted in better grain yield of the dwarf and low tillering cultivar under narrow row spacing. Higher leaf area index and crop growth rate were observed in 20- and 30-cm spaced rows 90 days after sowing, thereafter a drastic decrease was observed in 30-cm spaced rows. In conclusion, for harvesting maximum wheat productivity, tall and low tillering cultivars should be planted in 20-cm spaced rows. Medium stature and low tillering cultivars may be planted in 20 or 30-cm spaced rows, whereas low tillering dwarf cultivars should be planted in 10-cm spaced rows. 相似文献
80.
This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Province(KPK) of Pakistan. The primary data were collected by a direct elicitation method from 510 maize growers of KPK Province. Stochastic frontier model techniques were used for technical efficiency analyses. The results revealed that the mean technical efficiency difference between the two groups was 10.2%. The results of technical inefficiency effect modeling demonstrated that education of the household head, family size, number of married family members, off-farm income, farming experience, tractor drill, water irrigation through a lined course, certified seed, extension services, household saving variables, and a credit size variable had positive effects on technical efficiency for both credit constrained farmers(CCFs) and credit unconstrained farmers(UCCFs). In addition, age of household head and fragmented land values had negative effects on technical efficiency for both groups. However, the interest rate had positive and negative impacts on the technical efficiency of CCFs and UCCFs, respectively. Our results have significant implications for policies related to land use, interest rate, and banking sector expansion in the rural areas of Pakistan. 相似文献