不同储藏条件对牛肉品质的影响

为研究不同包装方式和储藏温度对牛肉品质的影响,以宰后24 h的牛背最长肌为材料,对其分别进行托盘、真空、涂膜3种方式包装,并置于（4±1） ℃冷藏及（-1.0±0.5） ℃冰温条件下储藏,并在储藏期间对牛肉的pH值、TVB-N含量、TBARS含量、微观结构以及挥发性成分进行检测。结果表明：储藏15 d后,冰温＋涂膜组牛肉的pH值和TVB-N含量最低,分别为6.23和11.59 mg/100 g;冰温＋涂膜组、冷藏＋涂膜组牛肉的TBARS值分别为0.35 mg/kg和0.39 mg/kg;电镜观察发现冰温＋涂膜组牛肉肌内膜结构相对完整,其他组都有不同程度松散和破坏;储藏期间牛肉中酮类、醛类、烃类、酯类物质的相对含量由低到高依次为：涂膜组＜真空组＜托盘组。综上所述,冰温储藏结合涂膜保鲜能更好地维持牛肉的品质,延长货架期。     

牛肉加热过程中水分迁移规律研究

采用100℃隔水加热方式加热牛肉28 min,每隔7 min采集一次样品,利用LF-NMR技术初步探讨牛肉加热过程中水分迁移规律。结果表明:随着加热时间的延长,牛肉蒸煮损失呈现上升趋势,剪切力不断增大,核磁数据显示牛肉内部水分状态组成变化显著,T2弛豫时间逐渐变短,不易流动水T22占比逐渐减少,自由水T23占比逐渐增多,且随着加热时间的延长,不易流动水和自由水很难在T2弛豫谱上分开,峰宽变大趋势明显,核磁成像结果显示加热会降低牛肉内部的水分含量。相关性分析结果表明:T21与牛肉的蒸煮损失呈显著正相关,T22与牛肉的蒸煮损失、剪切力呈显著负相关,T22峰面积占比与T2b、牛肉的蒸煮损失、剪切力呈显著负相关。由此得出加热处理对牛肉内部的水分分布和质构特性产生显著影响,同时两者之间存在相关性。     

紫色土丘陵坡地不同恢复阶段土壤生态化学计量特征

采用空间序列代替时间序列的方法,对湖南省衡阳市紫色土丘陵坡地不同恢复阶段(包括前期(Ⅰ)、中前期(Ⅱ)、中后期(Ⅲ)和后期(Ⅳ))不同土层(包括0～10 cm、10～20 cm、20～40 cm、40～60 cm、60～80 cm、80～100 cm 与0～100 cm土层)的土壤生态化学计量特征进行研究。结果表明：(1)随着植被恢复的进行,每个恢复阶段各土层土壤有机碳含量先升后降,呈现出倒“U”形规律,TN和TP的含量显著减小(P＜0.05),具有明显的“表聚性”, 每土层的4个恢复阶段的SOC的大小具有“波动性”,差异具有显著性(P＜0.05),TN和TP的含量的大小顺序均为：后期(Ⅳ)＞中后期(Ⅲ)＞中前期(Ⅱ)＞前期(Ⅰ),其差异达显著水平(P＜0.05);(2)随着植恢复的进行, 0～100 cm土壤SOC、TN和TP显著增加(P＜0.05), C/N、C/P和N/P显著减小(P＜0.05);(3)相关分析说明： C/N与SOC、SER呈极显著正相关(P＜0.01),与TN、TP、SWC、SBD呈极显著负相关(P＜0.01);C/P与SOC呈极显著正相关(P＜0.01),与SWC、SBD呈极显著负相关(P＜0.01);N/P与SOC、TN、TP、pH值呈显著或极显著正相关(P＜0.05或P＜0.01),与SBD、SER呈极显著负相关(P＜0.01)。研究结果说明,在植被恢复过程中,植被对土壤中N和P两种元素的需求相一致。     

姜黄素微胶囊对冷藏猪肉糜氧化稳定性及品质的影响

为提高冷藏猪肉糜的氧化稳定性和品质,以姜黄素为芯材,大豆分离蛋白和β-环糊精为壁材,利用冷冻干燥法将姜黄素微胶囊化。通过测定不同处理组（0.20 g/kg 姜黄素微胶囊、0.35 g/kg姜黄素微胶囊、0.50 g/kg姜黄素微胶囊、0.1 g/kg 丁基羟基茴香醚（BHA）和对照组）冷藏猪肉糜的硫代巴比妥酸反应物（TBARS）值、总巯基含量、总羰基含量、pH、蒸煮损失率及色差,研究姜黄素微胶囊对猪肉糜脂质和蛋白质的抗氧化效果及其对猪肉糜品质的影响。结果表明,添加0.50 g/kg姜黄素微胶囊的猪肉糜的TBARS值和总羰基含量显著低于对照组（P＜0.05）,总巯基含量显著高于对照组（P＜0.05）,与添加0.1 g/kg BHA效果接近,姜黄素微胶囊可以减少猪肉糜冷藏期间pH值和颜色的变化,显著降低猪肉糜冷藏过程中的蒸煮损失率。综上所述,0.50 g/kg姜黄素微胶囊能够显著抑制冷藏猪肉糜的脂肪和蛋白氧化,更好地保持其冷藏品质。     

复合香辛料提取物对冷藏猪肉糜氧化及品质特性的影响

为探究桂皮、生姜、八角茴香复合香辛料提取物对冷藏期间猪肉糜氧化稳定性及品质的影响,分别向猪肉糜中加入浓度为0.3%、0.7%、1.1%的香辛料提取物溶液,测定不同处理组的硫代巴比妥酸值（Thiobarbituric acid reactive substances,TBARS）、蛋白质羰基、总巯基、pH、蒸煮损失、色差、质构特性等指标,并通过电镜观察其微观结构。结果表明：添加复合香辛料提取物的猪肉糜TBARS值、羰基含量和巯基损失量显著低于空白组（P＜0.05）,添加浓度为0.7%和1.1%两组间无显著差异;与空白组相比,冷藏后期3个不同提取物浓度组肉糜的pH、蒸煮损失、L*值、a*值、质构特性均有显著改善（P＜0.05）,并降低了因氧化诱导引起的微观结构的改变,但1.1%浓度组肉糜a*值较其他浓度组低（P＜0.05）,说明高浓度的复合香辛料提取物对肉糜色泽有一定的负面影响。综上所述,添加浓度为0.7%的复合香辛料提取物可有效抑制冷藏猪肉糜的氧化和品质的劣变。     

微地形对大西沟野杏幼苗生境的气候和土壤温湿度的影响

摘 要：探究新疆霍城县大西沟野果林内的微地形对野杏幼苗生境的气候和土壤温湿度等环境因子的影响。在封育的野果林内设置样地，观测地形和野杏幼苗生长季的气温、光照、空气湿度和土壤温湿度，分析各环境因子和地形因子的关系。结果表明：（1）坡向与气温、光照强度和土壤温度呈极显著正相关(P＜0.01)，东南坡＞南坡＞东北坡，坡向与空气湿度、土壤含水量呈极显著负相关(P＜0.01)；（2）坡位与气温、光照强度呈极显著正相关(P＜0.01)，与土壤含水量呈显著负相关(P＜0.05)，不同坡位的环境因子没有显著性差异(P＜0.05)；（3）坡度与气温、光照强度以及土壤温度呈极显著正相关(P＜0.01)，缓中坡＞陡坡＞中坡＞缓坡，缓坡与其他坡度均呈显著差异(P＜0.05)；坡度与空气湿度以及土壤含水量呈显著负相关(P＜0.05)；（4）坡形与土壤含水量呈极显著负相关(P＜0.01)，对气候因子和土壤温度都无显著影响。地形变化对野杏幼苗生境的气候和土壤温湿度有显著影响，东南坡、上坡位、缓中坡以及凸坡形和相应的气候与土壤温湿度，是适宜野杏幼苗生存的生境条件。     

辽宁滨海稻区稻米RVA谱特征值及其与食味品质的关系

以54个水稻品种(系)为试材,研究了稻米RVA谱特征值及其与食味品质的关系.结果表明,RVA谱特征值间存在很好的相关性.食味值与回复值呈极显著负相关,与崩解值呈显著正相关,与消减值呈显著负相关,说明稻米RVA谱特征值与蒸煮食味品质关系密切.直链淀粉含量与最低粘度、最终粘度、消减值、回复值呈显著正相关,与崩解值呈显著负相关;蛋白质含量与最终粘度、消减值呈极显著正相关,与崩解值呈极显著负相关,与最低粘度、回复值呈显著正相关,与最高粘度呈显著负相关,说明RVA谱特征值能够充分反映直链淀粉和蛋白质含量.     

转反义trxs基因小麦籽粒蛋白组分的巯基含量与α-淀粉酶活性的关系

利用反义trxs基因特异引物,对扬麦5号转反义trxs基因株系00TY5的T4和T5代进行了PCR分子鉴定,并对其纯合株系籽粒蛋白质组分的巯基含量、α-淀粉酶活性及二者的相关性进行了测试.结果表明,00TY5的T4和T5代PCR分子检测均呈阳性.与非转基因植株相比,在籽粒成熟和后熟过程中,籽粒清蛋白巯基含量在开花后30 d至成熟后5 d平均降低33.2%,球蛋白巯基含量在开花后20d至成熟后5 d平均降低42.5%,均达极显著水平（P＜0.01）;醇溶蛋白和谷蛋白巯基含量有下降的趋势,但降低幅度较小;α-淀粉酶活性低,变异小,尤其在开花后35 d至成熟后10 d,平均比非转基因植株下降36.5%.各种蛋白质组分的巯基含量与α-淀粉酶的活性呈正相关关系,清蛋白巯基含量在成熟前与α-淀粉酶活性相关性达极显著水平（P＜0.01）;球蛋白巯基含量在成熟前10 d至成熟后10 d达显著水平（P＜0.05）;贮藏蛋白巯基含量与α-淀粉酶活性的相关性在各时段均较高.     

甘蓝型黄籽油菜主要品质性状分析

以不同来源的51份甘蓝型黄籽油莱种质为材料,对粒重、色泽、蛋白质、硫甙和芥酸含量等主要性状进行研究,结果表明:种质间千粒重差异大,变幅在1.54～4.76 g之间,平均为3.65 g,多数集中在3.4～3.8 g之间;影响种皮色泽的主要是黑色素和花色素;根据其含量的不同,可分为高花色素类、高黑色素类和低色素3个类群;种子颜色等级与种子含油量呈极显著的正相关,种子颜色等级与种子蛋白质含量呈极显著的负相关;种子舍油量为31.8%～46.4%,蛋白质含量为23%～34.9%,芥酸含量为0.56%～5.40%,硫甙含量为6.95%～76.43%;且种子的含油量与蛋白质含量呈极显著负相关,芥酸含量与硫甙含量呈极显著正相关,硫甙含量与含油量呈显著正相关.     

甘薯贮藏期呼吸强度与主要品质的变化研究

摘要：研究了6个甘薯品种在适温贮藏期间呼吸强度、干率、淀粉、可溶性糖、还原糖、蛋白质的变化及其相关性分析。结果表明,甘薯适温贮藏期间呼吸强度、可溶性糖含量变化呈高到低再到高的趋势曲线,且与其干率密切相关;淀粉含量在贮藏期呈现缓慢下降的趋势;甘薯块根干率与淀粉含量、呼吸强度呈极显著正相关,与蛋白质含量呈显著正相关;干率、淀粉含量和蛋白质含量都与还原糖含量呈极显著负相关;蛋白质与可溶性糖呈极显著负相关;可溶性糖与还原糖呈极显著正相关。     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Mechanisms and diversity of resistance to sorghum shoot fly,Atherigona soccata

Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums.     

Reaction of tritordeum to Fusarium culmorum and Septoria nodorum

Summary Hordeum chilense is a wild barley extensively used in wide crosses in the Triticeae. It could be a valuable source of resistance to Fusarium culmorum and Septoria nodorum. Some H. chilense x Triticum spp. amphiploids, named tritordeums, were more resistant than the parental wheat line to these diseases, others were not. Average contents of ergosterol and deoxynivalenol (DON) suggested that resistance to colonization by Fusarium was the highest for Hordeum chilense, followed by tritordeum and wheat in decreasing order. In particular, the H. chilense genotypes H7 and H17 enhanced the wheat resistance to F. culmorum in its tritordeum offsprings. Resistance to S. nodorum in tritordeum was not associated with tall plant height. There is sufficient genetic variation for resistance to F. culmorum and S. nodorum among tritordeum to allow the breeding of lines combining short straw and resistance to both diseases.     

Disease resistance in protected crops and mushrooms

Summary Cultivars of tomatoes, cucumbers, lettuce and peppers have been bred for resistance to one or more pathogens. Some tomato and cucumber cultivars have resistance to a wide range of diseases. Resistance has been transient in many cases and a succession of cultivars with new genes or new combinations of resistance genes has been necessary to maintain control. There has been a number of notable exceptions and these have included durable resistance to such pathogens asFulvia fulva and tomato mosaic virus. With lettuce the resistance situation is complicated by the occurrence of fungicide resistant pathotypes. There are no strains ofAgaricus bisporus purposely bred for disease resistance.In protected flower crops only resistance to Fusarium wilt in carnations has been purposely bred but differences in disease resistance are apparent in cultivars of many ornamental crops. This is particularly so in chrysanthemums where there are cultivars with resistance to many of the major pathogens. Similar situations occur with other flower crops and pot plants. Cultivars of some species have not been systematically investigated for resistance.The need for genetic resistance will increase with the further reduction, in the limits on pesticide use and an increasing public awareness and importance of pesticide pollution.ADAS is an executive agency of the Ministry of Agiculture, Fisheries and Food and the Welsh Office.     

Relation between wheat-rye crossability and seed set of common wheat after pollination with other species in the Hordeae

Summary Cultivars of common wheat (Triticum aestivum L. em. Thell.) of high wheat-rye (Secale cereale L.) crossability set more seed with pollen of other related species than did wheats of low wheat-rye crossability. This was found to be true for pollen parents from the genera Triticum, Aegilops, Secale, Agropyron and Elymus.     

Evolution under domestication involving disturbance of genic balance

Summary An hypothesis is developed that the rapid change from wild plants into domesticated crops principally involves the selection of alleles with non-functional gene products which leads to reduced control of the highly integrated metabolism and morphogenesis previously accumulated by lengthy natural selection. Such disturbance of the genome produces altered physiological and morphological development which, although deleterious in nature, serves mankind better and has been selected.