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41.
Rasheed F Richard B Le Thiec D Montpied P Paillassa E Brignolas F Dreyer E 《Tree physiology》2011,31(11):1183-1193
Genetic differences in δ13C (isotopic composition of dry matter carbon) have been evidenced among poplar genotypes at juvenile stages. To check whether such differences were maintained with age in trees growing in plantations, we investigated the time course of δ13C as recorded in annual tree rings from different genotypes growing at three sites in southwestern France and felled at ～15-17 years. Wood cores were cut from tree discs to record the time course of annual basal area increment (BAI). The isotopic ratio δ13C was recorded in bulk wood and in extracted cellulose from the annual rings corresponding to the period 1996-2005. Discrimination against 13C between atmosphere and tissues (Δ13C) was computed by taking into account the inter-annual time course of δ13C in the atmosphere. Annual BAI increased steadily and stabilized at about 8 years. An offset in δ13C of ～1‰ was recorded between extracted cellulose and bulk wood. It was relatively stable among genotypes within sites but varied among sites and increased slightly with age. Site effects as well as genotype differences were detected in Δ13C recorded from the cellulose fraction. Absolute values as well as the genotype ranking of Δ13C remained stable with age in the three sites. Genotype means of Δ13C were not correlated to annual BAI. We conclude that genotypic differences of Δ13C occur in older poplar trees in plantations, and that the differences as well as the genotype ranking remain stable while trees age until harvest. 相似文献
42.
Wheat seed storage proteins: Advances in molecular genetics,diversity and breeding applications 总被引：1，自引：0，他引：1
Awais Rasheed Xianchun Xia Yueming Yan Rudi Appels Tariq Mahmood Zhonghu He 《Journal of Cereal Science》2014
Wheat seed storage proteins, especially glutenins and gliadins, have unique functional properties giving rise to a wide array of food products for human consumption. The wheat seed storage proteins, however, are also the most common cause of food-related allergies and intolerances, and it has become crucially important to understand their composition, variation and functional properties and interface this knowledge with the grain handling industry as well as the breeders. This review focuses on advances in understanding the genetics and function of storage proteins and their application in wheat breeding programs. These include: (1) The development and validation of high-throughput molecular marker systems for defining the composition and variation of low molecular weight glutenin subunits (LMW-GS) genes and a summary of the more than 30 gene-specific markers for rapid screening in wheat breeding programs; (2) The identification of more than 100 alleles of storage proteins in wild species provide candidate genes for future quality improvement; (3) The documentation of quality effects of individual LMW-GS and HMW-GS for improving end-use quality; and (4) The analysis of α-gliadin genes on chromosomes 6A and 6D with non-toxic epitopes as potential targets to develop less toxic cultivars for people with celiac disease. Genomic and proteomic technologies that will continue to provide new tools for understanding variation and function of seed storage proteins in wheat are discussed. 相似文献
43.
Rasheed Adnan Wassan Ghulam Mustafa Khanzada Hira Solangi Abdul Malik Han Ruicai Li Huijie Bian Jianmin Wu Ziming 《Genetic Resources and Crop Evolution》2021,68(5):1889-1903
Genetic Resources and Crop Evolution - Aluminium toxicity is adversely affecting the rice growth and production in acidic soils of developing countries. Rice is popular and stable crop which meets... 相似文献
44.
Variyar PS Ahmad R Bhat R Niyas Z Sharma A 《Journal of agricultural and food chemistry》2003,51(27):7945-7950
Volatile aroma principles, nonvolatile taste constituents (caffeine and chlorogenic and caffeic acids), and glycosidically bound aroma compounds of monsooned and nonmonsooned raw arabica coffee were analyzed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). Among the most potent odor active constituents known to contribute to the aroma of the green beans, 3-isopropyl-2-methoxypyrazine, 3-isobutyl-2-methoxypyrazine, 4-vinylguaiacol, beta-damascenone, (E)-2-nonenal, trans,trans-2,4-decadienal, phenylacetaldehyde, and 3-methylbutyric acid were detected by GC-MS in both samples. A decrease in content of methoxypyrazines and an increase in 4-vinylguaiacol and isoeugenol resulted in a dominant spicy note of monsooned coffee. These phenolic compounds exist partly as their glycosides, and their release from the bound precursors during monsooning accounted for their higher content in monsooned coffee. A considerable decrease in astringent chlorogenic acid as a consequence of hydrolysis to bitter caffeic acid was noted in monsooned coffee. Radiation processing of nonmonsooned beans at a dose of 5 kGy resulted in an increased rate of monsooning. At this dose a quantitative increase in most of the aroma active components could be observed in all samples studied. Hydrolysis of chlorogenic acid to caffeic acid was noted in radiation-processed monsooned coffee beans irrespective of whether the treatment was carried out before or after monsooning. These changes were, however, not observed in irradiated, nonmonsooned coffee beans, suggesting an enzymatic rather than a radiolytic cleavage of chlorogenic acid. A rationale behind the mechanism of monsooning and radiation-induced enhancement of the monsooning process is discussed. 相似文献
45.
Muhammad Ather Nadeem Asif Tanveer Rizwan Maqbool Ali Zohaib Muhammad Asif Shehzad 《Archives of Agronomy and Soil Science》2017,63(3):344-351
Little is known of glyphosate-induced hormesis in weeds and how this might influence weed management. To test the hormetic effect of low doses of glyphosate on broad-leaved weeds, two experiments were conducted, in the laboratory and the screenhouse. The hormetic effects of glyphosate solution in growth media (0, 65, 130, 250, and 500 g acid equivalent (a.e) ha?1) and foliar spray (0, 4, 8, 16, 32, and 64 g a.e. ha?1) were tested on four broad-leaved weeds (Coronopus didymus, Chenopodium album, Rumex dentatus, and Lathyrus aphaca). Glyphosate solution in the range 65–250 g a.e. ha?1 stimulated the germination and seedling growth of all tested weeds. However, at 500 g a.e. ha?1 inhibition of germination and growth was observed. Foliarly applied glyphosate in the range 4–32 g a.e. ha?1 increased root and shoot length, dry biomass, and seed production ability of all four weeds species; however, the stimulatory response was species dependent. These results indicate that glyphosate hormesis could play a significant role in altering crop/weed competition and might influence weed management. 相似文献
46.
基于优化SIFT算法的无人机遥感作物影像拼接 总被引：2，自引：1，他引：1
针对作物遥感影像因对比度低所导致的使用尺度不变特征变换算法(scale-invariant feature transform,SIFT)提取特征点数目少,拼接效果不理想的情况,提出了一种基于图像锐化的自适应修改采样步长的非极小值抑制拼接算法,该算法在图像预处理中引入锐化滤波器对平滑后的图像进行卷积,增强图像细节,增加特征点提取数目,同时通过基于尺度的自适应修改采样步长,使图像特征点分布更加均匀,根据低对比度作物遥感影像的成像特性,采用非极小值抑制,提高图像匹配效率。在查找匹配点的过程中,引入最优节点优先算法(best-bin-first,BBF)查找最近邻与次近邻,采用随机抽样一致算法(random sample consensus,RANSAC)优选特征点。通过试验验证,该文改进后的算法相比于标准SIFT算法,在处理低空作物遥感影像时,特征点提取数目平均增加77.5%,特征点匹配对数平均增加15对,对于标准SIFT算法无法匹配的低对比度作物遥感影像,提取到了8对以上的匹配点对,满足了拼接条件。该改进算法相对于标准SIFT算法更适于低对比度遥感影像的拼接。 相似文献
47.
Rizwan Muhammad Noureen Shamaila Ali Shafaqat Anwar Sarwat Rehman Muhammad Zia ur Qayyum Muhammad Farooq Hussain Azhar 《Journal of Soils and Sediments》2019,19(11):3749-3759
Journal of Soils and Sediments - The majority studies used the biochar or nanoparticles alone in metal-contaminated soils while less is known about the combined use of these amendments in... 相似文献
48.
Naveed-ul-Haque Muhammad Akhtar Muhammad Uzair Munnawar Rizwan Anwar Saba Khalique Anjum Tipu Murtaza Ali Ahmad Fayyaz Shahid Muhammad Qamer 《Tropical animal health and production》2018,50(5):1125-1130
Nitrogen efficiency of lactating buffalo can be increased by providing dietary crude protein (CP) precisely to the requirement. Twelve lactating Nili-Ravi buffaloes (6 primiparous and 6 multiparous) at 76?±?37.5 days in milk (DIM) were used in this study. The treatments were diets providing three levels of CP (% DM basis): (1) low-protein?=?11%; (2) medium-protein?=?13.1%; (3) high-protein?=?14.2% according to a 3?×?3 Latin square design. The period length of each treatment was 21 days and the total duration of experiment was 63 days. The diets were designed to provide similar energy. The nitrogen intake of buffalo increased linearly by increasing CP levels. Dry matter intake showed a tendency toward decrease in quadratic fashion, whereas milk yield decreased linearly in high-protein diet. No effect was observed on milk protein yield and content. Increasing the dietary CP levels increased plasma urea nitrogen, whereas glucose and triacylglycerol levels remain unaffected. Efficiency of dietary nitrogen utilization to milk averaged 21% and showed both linear and quadratic decreases by increasing the protein supply levels. In conclusion, low CP level showed higher milk production with low plasma urea nitrogen and high nitrogen efficiency in this experiment.
相似文献49.
Naila Jabeen Muhammad Iqbal Muhammad Rizwan Abdul Jabbar Mujahid Farid 《Archives of Agronomy and Soil Science》2016,62(5):648-662
A pot experiment was conducted to evaluate the role of glycinebetaine (GB) in chromium (Cr) tolerance in mung bean (Vigna radiata L.) grown in Cr-stressed soil. Three concentrations of Cr (0, 250 and 500 µM) were tested with three (0, 50 and 100 mM) concentrations of foliar-applied GB. Cr alone led to a significant decrease in plant growth, biomass, and concentrations of chlorophyll a, b and carotenoids. Cr concentration and electrolyte leakage significantly increased in plants with increasing Cr levels in the soil. Lower Cr stress enhanced the activities of superoxide dismutase (SOD), peroxidases (POD) and catalase (CAT), while higher Cr concentrations decreased the activities of these enzymes. Foliar application of GB successfully alleviated toxic effects of Cr on mung bean and increased plant growth, biomass and chlorophyll contents under Cr stress. GB application reduced Cr accumulation and electrolyte leakage in plants and enhanced the activities of antioxidant enzymes in both shoots and roots as compared with Cr treatments alone. These findings suggest that foliar-applied GB alleviated Cr-induced oxidative stress in mung bean by reducing Cr uptake. The protective effect of GB against Cr stress varies with the concentrations of GB and Cr stress applied. Thus, further studies are still needed to specify the concentrations of GB required for detoxification of specific Cr concentrations under various climatic conditions. 相似文献
50.
Nowshad M. Rasheed 《Journal Of Applied Aquaculture》2013,25(4):352-358
EXCEL is a new breed of O. niloticus developed by combining improved within family selection and rotational mating. A study was carried out to investigate early growth performance in an indoor recirculating aquaculture facility. The first study compared average body weight (ABW), average daily growth rate (ADGR), survival and food conversion efficiency (FCR) of first generation fry of imported EXCEL and non improved O. niloticus (NS) fry over an initial nursery stage from swim-up to 5.0 g (56 days, test 1) and a second nursery stage from ～3 to 15 g (28 days, test 2). ABW and ADGR of EXCEL fry was 4–5 times that of non improved tilapia during the first 56 days, which advantage was maintained over the second nursery stage also. In addition, FCR was lower in EXCEL compared with NS. 相似文献