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961.
Linseed (Linum usitatissimum L.) is an important dual-purpose, industrial crop. Its seeds are used for the extraction of oil and stem for fibres. However, the production of linseed is not going parallel with the increasing demand of its products. The present work was carried out with an aim to find out whether exogenous application of gibberellic acid (GA3) with or without graded levels of nitrogen (N) and phosphorus (P) could improve the performance of three linseed genotypes Parvati, Shekhar and Shubhra together with minimizing the costly fertilizer input and losses. Four combinations of N and P, viz., 0 mg N+0 mg P kg?1 soil (N0P0), N13.4P4.46, N26.8P8.94 and N40.2P13.4 were constituted. Half dose of each combination was applied basally at the time of sowing and remaining half dose was given at 40 d after sowing (DAS) as foliar spray along with 10?6 mol L?1 GA3. Prior to sowing, the seeds of each linseed genotype were grouped in to two, one group of seeds was soaked in 0 mol L?1 GA3 (control) and the other group was soaked in 10?6 M GA3 solution, each for 8 hours. Treatments were comprised of (i) 0 mol L?1 GA3+N0P0 (T0, control), (ii) 10?6 mol L?1 GA3 + N134P446 (T1), (iii) 10?6 mol L?1 GA3+N26.8P8.94 (T2) and (iv) 10?6 mol L?1 GA3+N40.2P13.4 (T3). The crop performance was assessed in terms of growth, physiological and biochemical parameters at 60 and 75 DAS and yield attributes at harvest (175 DAS). The results showed a parallel increase in most of the parameters with increasing levels of N and P. However, application of 10?6 mol L?1 GA3 in association with N26.8P8.94 proved best, it enhanced seed yield, oil yield and fibre yield by 83.3, 97.3 and 78.7%, respectively accompanied with increase in net photosynthetic rate, carbonic anhydrase activity and dry matter accumulation. Among the genotypes tested, Shubhra performed best, while Parvati the least for most of the parameters studied. Thus, combined application of 10?6 mol L?1 GA3 plus N26.8P8.94 proved best and can be recommended to exploit the linseed as a dual-purpose crop for good yield of seed and fibre.  相似文献   
962.
Land evaluation is the process of predicting land use potential on the basis of its attributes. In the present study, the physical land suitability evaluation approach was investigated for specific cereal crops including irrigated wheat, barley, grain maize and sorghum, based on FAO land evaluation frameworks (FAO, 1976, 1983, 1985) and the proposed method by Sys et al. (1991) at Mashhad Plain, Northeast Iran. Twenty eight soil profiles were studied on seven land units by a precise soil survey and their morphological and physicochemical properties were determined. Climatic and land qualities/characteristics of four cereal crops were determined using the tables of crop requirements developed by Sys et al. (1993). An interpolation function was used to map values to scores in terms of land qualities/characteristics for land utilization types and the evaluation was carried out according to parametric approaches. The interpolation technique using GIS functions helped in managing the spatial data and visualizing the results. Our results indicated that the most important limiting factors for irrigated wheat and barley cultivations are soil physical and fertility/chemical properties, while the production of irrigated grain maize and sorghum is mainly limited by climatic conditions at Mashhad Plain. It was shown that all land units suitable for irrigated wheat cultivation overlap with that of barley, whereas the same limiting factors resulted in the overlapping of the irrigated grain maize production area with that of sorghum. The results of the physical land suitability evaluation for specific cereal crops indicated the priority of irrigated barley and wheat cultivations over irrigated grain maize and sorghum at the study area.  相似文献   
963.
Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran.  相似文献   
964.
965.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one.The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
966.
This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
967.
提出利用 GIS与 TM数据集成技术估算中国南方丘陵山地早稻种植面积的方法 .该方法首先利用 ARC/INFO对土地利用现状图进行数字化 ,建立拓朴关系后将其转化为栅格 ,然后进行投影变换 ,使土地利用现状图、行政图、TM数据具有相同的坐标 ,最后利用土地现状图 ,提取水田分布图 ,对水田分布图进行分类估算早稻种植面积 .不同方法比较结果表明 :非监督分类法不能用于提取丘陵山区的水稻种植面积 ;只用 TM资料估算龙游县早稻面积 ,与统计数据相比 ,平行六面体分类法、最大似然分类法分别达到 82 .83 %和 59.95% ;而用 GIS与 TM数据资料集成技术对水田分布图进行分类估算早稻面积 ,平行六面体分类法、最大似然分类法的估算精度分别达到 93 .98%和 60 .65% ,所以利用平行六面体分类法对南方丘陵山地早稻种植面积估算是可行的 .  相似文献   
968.
The effects of moisture content (8%, 10%and 12%), variety (Tarom and Fajr) and parboiling on milling quality of rice as a function of milling recovery (MR), head rice yield (HRY), degree of milling (DOM) and whiteness were investigated. The parboiled grains was prepared with three soaking temperatures of 25 oC, 50 oC and 75 oC and three steaming times of 10, 15 and 20 min. As a result of parboiling, the increasing rates of MR and HRY values were 7.8%and 14.3%for Tarom and 9.8%and 10.0%for Fajr, respectively, and the decreasing rates for DOM and whiteness were 6.6%and 10.8%for Tarom and 6.8% and 10.5% for Fajr, respectively. Moreover, decreasing moisture content to 8%maximized MR (75.8% for Tarom and 74.3% for Fajr) and HRY (65.8% for Tarom and 57.0% for Fajr) while increasing that to 12%revealed maximum values of DOM (6.1%for Tarom and 6.2%for Fajr) and whiteness (24.8%for Tarom and 28.2%for Fajr).  相似文献   
969.
There is a growing interest to develop environmentally friendly surfactants for utilization with supercritical carbon dioxide (scCO2), which is a "green" solvent with many industrial applications. The goal of the present work was to separate the commonly used soybean lecithin into a phospholipid-rich fraction, acetylate this fraction, and then test its solubility in scCO2 to gauge its suitability as a surfactant for potential scCO2-based applications. Soybean lecithin was first purified by fractionation using acetone and ethanol and then acetylated with acetic anhydride. The acetylated lecithin was further purified by fractionation with acetone to separate the acetylated fraction from the nonacetylated fraction. High-performance liquid chromatography and electrospray ionization mass spectrometry were utilized to characterize these fractions. The various acetylated phospholipid fractions were then tested for solubility in scCO2 under various pressures and temperatures using both a cloud-point and a Fourier transform infrared apparatus. Acetylation was found to increase the solubility of the phospholipids in scCO2, and N-acetylated phosphatidylethanolamine (NAc-PE) was found to be the most soluble component of the acetylated phospholipids.  相似文献   
970.
BACKGROUND: Progressive cognitive decline is one of the hallmark symptoms of Alzheimer's disease (AD) which can be modeled by beta-amyloid injection into specific regions of brain. Since epigallocatechin-3-gallate (EGCG) is a potent antioxidant agent which its role against oxidative stress and inflammation has been shown in prior studies, we tried to determine whether EGCG administration protects against beta-amyloid-induced memory and coordination impairment in rats. METHODS: Animals (male Wistar rats) were divided into four groups: sham operated, EGCG-pretreated sham operated (sham+EGCG), untreated lesion (lesion), and EGCG-pretreated lesion (lesion+EGCG). Animals in lesion, lesion+EGCG, and sham+EGCG groups received sterile saline or saline plus EGCG (10 mg/kg) intraperitoneally one day pre-surgery and every other day for three weeks. The lesion was induced one day after EGCG pretreatment by injection of 4 microl of sterile saline or water containing 2 nmol/microl beta-amyloid (1-40) into the hippocampal fissure. For behavioral analysis, psychomotor coordination (PMC) index and spontaneous alternation behavior were assessed using Rota-rod Treadmill and Y-maze, respectively at the third week post-lesion. RESULTS: We found that beta-amyloid (1-40) injection into hippocampus can decrease these behavioral indexes in lesion group in comparison with sham group which is similar to behavioral changes in AD. On the other hand, pretreatment with EGCG can improve the PMC index and spatial Y-maze alternation in the lesion+EGCG group in comparison with lesion group. CONCLUSION: We concluded that EGCG can be effective in restoring beta-amyloid-induced behavioral derangements in rats regarding coordination and memory abilities.  相似文献   
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