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11.
Eleven Pakistani hard white spring wheat cultivars, along with one durum wheat and two hard white American‐grown wheat cultivars, were evaluated for their high‐molecular‐weight (HMW) glutenin subunit composition via sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). The relationships among different quality characteristics and between these characteristics and HMW glutenin subunits were computed. Three to six HMW glutenin subunits were observed in Pakistani bread wheat cultivars. The presence of HMW glutenin subunits was not affected by growth locations or crop years. However, variations in intensities were observed. Correlations were noticed between certain HMW glutenin subunits and some quality attributes, such as protein, farinograph dough development time, farinograph water absorption, loaf volume and mixograph peak height. The presence of HMW glutenin subunit 20 in the older wheat cultivars C591 and C273, known for excellent chapati quality, indicated a possible relationship between this band and chapati quality. This observation will need to be confirmed by testing a larger number of wheat samples known to have characteristics for both good and poor chapati quality. © 2000 Society of Chemical Industry  相似文献   
12.
为深入研究和评价烤烟新品种的丰产性、稳定性和品种生态布局,通过引入新型分析工具GGE模型,对2011年中间香型烟叶产区7个试点、11个烤烟新品种(系)的产量和产值进行了直观比较分析。结果表明,GGE双标图解释了产量总变异的71.9%和产值总变异的64.4%,具有真实代表性。GGE双标图显示,参试材料间丰产和稳产性差异很大,有些材料对某些环境具有特殊适应性。11个新品种(系)中,毕纳1号和贵烟1号总体表现为丰产、稳定和广适,同时毕纳1号、秦烟98和HB032分别为区1(遵义、武隆、桑植)、区2(旬阳、蒙阴)和区3(贵定、成丰)的丰产新品种(系)。这为中间香型烟叶产区烤烟新品种的筛选和评价提供了借鉴。  相似文献   
13.
Various cultivars of almonds (“Ferragnes,” “Guara,” “Largueta,” and “Marcona”) and hazelnuts (“Negret,” “Pauetet,” and “Tonda”), particularly their virgin oils and by‐products, are evaluated in this study. The almond and hazelnut virgin oils present high contents of oleic acid (59–73% and 76–80%, respectively) and α‐tocopherol (420–542 and 310–378 mg kg–1, respectively), as compared with other virgin vegetable oils. Aldehydes are the major contributors to their aromatic profile (54–74% almond oil and 30–40% hazelnut oil of total content), especially, benzaldehyde in almond oils (1.35–7.52 mg kg–1), and hexanal in hazelnut oils (0.99–1.27 mg kg–1). Statistical differences exist between the virgin almond and hazelnut oils and their varieties, for most of the chemical compounds studied. While all the nut varieties are high in polar phenolic compounds, “Ferragnes” almonds (1262 mg kg–1) and “Negret” hazelnuts (1720 mg kg–1) stand out. Accordingly, high antioxidant activity is also observed. Finally, the residual cakes may be considered a good source of polar phenolic compounds (823–2064 mg kg–1 almond cakes, 2261–4179 mg kg–1 hazelnut cakes), possessing high antioxidant capacity with potential applications of these by‐products as functional ingredients in food and non‐food formulations. Practical Applications: Virgin nut oils are gaining consumers’ preference due to their unique organoleptic attributes and potential health effects. It is therefore very relevant to establish their specific chemical composition, directly related to their properties, and that are greatly affected by the cultivar.  相似文献   
14.
吴林 《计算机科学》2001,(6):469-472
概述了近20年来波兰水果产量,栽培的果树品种构成,主栽品种,以及各种水果产品的供需状况和果树科研情况。  相似文献   
15.
The effects of genetic, pre-harvest (season of harvest, spear diameter, spear portion and spear tip color) and post-harvest factors (storage and domestic preparation practices, e.g., peeling and cooking) on total phenolic, flavonoid and ascorbic acid content of white asparagus spears and their correlation with antioxidant capacity (DPPH and FRAP) were studied. Results showed that genetic material was important for the total phenolic content but not season of harvest, spear diameter or storage. Violet spear tips and apical spear portions showed the largest amount of total phenolics. Peeling did not affect total phenolics in fresh asparagus, whereas it reduced their content in stored asparagus, while cooking resulted in an increase in both fresh and stored asparagus. However, the soluble extract of total phenolics and flavonoids were minor and the missing significance of phenolics and flavonoids in antioxidant capacity of white asparagus spears depends on these small amounts.  相似文献   
16.
As a part of a global project aimed at comparing the physiology of several grapevine ( Vitis vinifera L.) cultivars, we tested plant cultivation in trenches under semi-controlled conditions. Vegetative growth of vines of two cultivars, Pinot Noir and Merlot, from different locations, were followed during a 3-year period. Roots of trench-grown vines grew widely, leading to a root architecture closer to that observed under field conditions than that of potted vines. In addition, the root system could be sampled exhaustively for analyses. Although morphologically different, vines of the two cultivars exhibited similar patterns in dry matter production during the whole period, except at early flowering in year 3. Surprisingly, perennial parts accounted for this difference, though both cultivars were grafted onto the same SO4 rootstock clone. Consistently, vines exhibited root necrosis at any sampling date throughout spring, this process affecting more roots for the Pinot Noir/SO4 combination than for Merlot/SO4.  相似文献   
17.
Assimilate translocation in mature grapevines (cv. Gewürztraminer and cv. Harslevelü) under field conditions was investigated during the growth season by quantifying individual sugars and organic acids in mature leaves, shoot bark and berries, as affected by girdling the shoot just above the bunches. Tissue was sampled at berry set, pea size, veraison and ripeness stages of the vine. Invertase activity was determined in the shoot bark at ripeness. In the leaves, malic acid concentrations reached lowest levels at pea size, but increased thereafter. Tartaric acid decreased after peaking at pea size stage. Tartaric acid concentrations increased with girdling. Despite the increase in leaf age, sucrose concentrations remained virtually stable during the season, emphasising the importance of mature leaves for nourishing bunches. Girdling resulted in a build‐up of sucrose in the leaves. In the bark, malic and tartaric acid stayed more or less the same during the growth period, but increased above the girdle. As a result of phloem disruption, sucrose also increased. The increase in glucose and tartaric acid is believed to result from catabolic cleavage of sucrose by invertase. Invertase activity was evident in the bark (of mature Harslevelü vines) at ripeness, which may indicate involvement in osmotic adjustments and gradients in the bark/phloem structure. In the berries, malic and tartaric acids reached peak concentrations at pea size. The volume increase during the ripening period, and in the case of malic acid also respiratory loss, resulted in a decrease in organic acid concentration. Malic acid continued to decrease after the initial decline, whereas tartaric acid stayed virtually stable. Girdling had no marked effect on organic acid accumulation in the berries. Sucrose concentrations were low during the first part of the season, but increased thereafter. Sucrose concentrations during ripening increased with girdling, which may represent a concentration effect and/or import from the rest of the vine. Sucrose concentrations (in mature Harslevelü vines) were indeed lower below than above the girdle. Comparison of sucrose concentrations in the leaves, bark and berries showed the existence of a decreasing concentration gradient, in line with the source:sink transport concept. An equally prominent decrease in sucrose:glucose ratio in the berries from the start of the ripening period indicates that vacuolar integrity (compartmentation) was affected in the ripening berry, most probably allowing hydrolysis of sucrose by invertase and decreasing osmotic potential within the berry. The results provide further evidence for the hypothesis of an osmotic gradient driven transport to the berry.  相似文献   
18.
19.
The life table parameters and digestive enzymatic activity of Sitotroga cerealella Olivier (Lepidoptera: Gelechiidae), an important insect pest of grains, were studied under laboratory conditions (25 ± 1 °C, relative humidity of 65 ± 5% and a photoperiod of 16: 8 (L: D) h). Seeds of ten barley cultivars including Bahman, CB-84-10, Fajr30, Makuyi, Nosrat, Yousof, 12A1, 13A1, 18A1 and 19A1 were used as host diet. S. cerealella showed the shortest developmental time and the highest survival and fecundity after feeding on cultivar 19A1. The longest developmental time and the lowest fecundity were on cultivars Bahman and Fajr30, respectively. The gross and net reproductive rates and intrinsic rate of increase were the highest when S. cerealella was reared on cultivar 19A1. However, a corresponding decrease in these parameters was observed on cultivar Fajr30. Fourth instar larvae fed on cultivar 19A1 showed higher α-amylase activity than those fed on other barley cultivars. However, S. cerealella larvae exhibited no significant difference in proteolytic activity among barley cultivars. Correlation analyses showed that high correlations existed between the life table parameters and α-amylase activity on one side and particle size index on the other. It is suggested that nutritional quality, especially seed hardness, may be the major factor responsible for the susceptibility of barley cultivars to S. cerealella.  相似文献   
20.
BACKGROUND: Quality of tea depends on the cultivar and climatic conditions. Biochemical pathways within the plant and climatic factors can result in noticeable changes in chemical composition, which determine the quality of tea. Black tea quality attributes are influenced by various forms of catechins, namely gallated, non‐gallated, dihydroxylated and trihydroxylated catechins and their ratios. Hence the variations in grouped catechins and their synthesizing enzyme in relation to quality of south Indian black tea grown in different seasons and different cultivars were studied. RESULTS: Gallated, non‐gallated, dihydroxylated, trihydroxylated catechins and catechin index were significantly higher in crop shoots harvested during summer. A significant and wide diversity in various forms of catechins was noticed among the cultivars tested. Among the cultivars, UPASI‐3 registered the higher amount of various forms of catechins and activity of phenylalanine ammonia lyase (PAL), followed by UPASI‐9 and UPASI‐17 respectively, while the lowest amount was exhibited by ‘Assam’ seedlings and TRI‐2043. CONCLUSION: Overall quality as evaluated by tea tasters was positively correlated to the cultivars and seasons tested. This positive correlation can be attributed to higher levels of grouped catechins and PAL activity. Thus the contents of various forms of catechins could be the most important quality parameter of the south Indian black teas. Copyright © 2010 Society of Chemical Industry  相似文献   
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