优化雪莲果烫漂护色条件的研究

采用正交试验筛选雪莲果果块烫漂护色的工艺条件。试验结果表明,雪莲果最佳烫漂护色条件为:温度80℃,时间3 min,柠檬酸质量分数0.25%。     

真空糖制雪莲果的工艺优化

以雪莲果块根为原料,研究了护色、热烫、硬化、糖浓度、果胶和柠檬酸的添加量、真空度、抽空时间、抽空温度、烘制温度等因素对果脯品质的影响。通过试验得到适宜的工艺条件为:柠檬酸护色液0.5%,热烫时间2 min,氯化钙硬化液0.3%,糖质量分数60%,果胶0.25%+柠檬酸0.2%,真空度0.06 MPa,抽空时间20 min,抽空温度60℃,并在60℃下烘制24 h。该工艺条件下制作的产品质量好。     

不同护色剂处理对雪莲果果脯护色效果的影响

以雪莲果为材料制备雪莲果果脯，研究不同护色剂对雪莲果果脯护色效果的影响，通过单因素试验和正交试验优化雪莲果果脯护色剂的配方。结果表明：雪莲果片厚度6 mm，护色剂最佳配方为：植酸0.25%、柠檬酸1.0%、抗坏血酸1.2%和氯化钠1.2%。在此条件下，制备的雪莲果果脯呈现淡黄色，且软硬适中，感官品质最佳。     

响应面法优化雪莲果果脯加工工艺

以雪莲果为主要原料,利用单因素试验结合响应面法优化雪莲果果脯加工工艺。结果表明,雪莲果果脯最优加工工艺为：采用浓度为3 g/L的柠檬酸护色,蔗糖添加量30%,糖渍时间30 h,60 ℃干燥12 h。在此工艺条件下加工的雪莲果果脯色泽金黄,晶莹剔透,口味甜度适中,口感软糯,具有浓郁的雪莲果风味,感官评分（91.6±0.3）分,理化指标及微生物指标均符合相关要求,是一款特色果脯类产品。本研究成果可为雪莲果产业发展提供一定的理论参考。     

雪莲果果浆护色配方的研究

选用VC、柠檬酸、亚硫酸钠3种护色剂对雪莲果果浆进行护色正交试验．分析比较不同护色剂对雪莲果果浆的护色效果。试验结果表明,3种护色剂的护色效果先后顺序依次为亚硫酸钠〉柠檬酸〉VC。最佳护色配方是：0．20％VC,0．20％柠檬酸,0．15％亚硫酸钠,3者共同使用时可取得良好的护色效果。     

低糖玫瑰果果酱的加工工艺

玫瑰果中含有大量对人体有益的营养成分,且果胶含量较高,适合制作果酱。本试验研究了低糖玫瑰果果酱的制作工艺和配方。结果表明,在玫瑰果果浆中添加20％白砂糖、0．1％柠檬酸、0．03％氯化钙和0．1％琼脂＋0．1％果胶复合稳定剂,浓缩时间20min,制成的玫瑰果果酱产品可溶性固形物含量为26％,组织状态均匀,口感细腻滑润,色泽鲜红,具有淡淡的玫瑰果香味。     

速冻紫皮洋葱护色工艺的研究

紫皮洋葱速冻后会因花青素的损失而导致色泽变浅,品质下降。本文采用色差分析的方法,对速冻紫皮洋葱的护色工艺进行了研究。结果表明,加热护色可较大程度地提高速冻紫皮洋葱花青素的保存量,其最佳护色工艺为:速冻紫皮洋葱经浓度为1.2%的CaCl2溶液浸泡15 min后,进行加热护色,加热温度为60℃,加热时间维持32 s。在此护色工艺条件下的速冻紫皮洋葱TCD(总色差)为1.27,护色效果最好。     

低糖雪莲果蛋糕的研制

以雪莲果果浆、面粉、白砂糖、鸡蛋等为原料,研制营养丰富、品味纯正、适合广大消费者及特殊人群需求的低糖雪莲果蛋糕。通过正交试验确定最佳产品配方为：鸡蛋500 g、白砂糖70 g、面粉300 g、雪莲果果浆125 g,可生产出风味独特、营养丰富的低糖雪莲果蛋糕。     

烘烤型雪莲果薯片加工工艺研究

以雪莲果为原料,将果汁加入到马铃薯全粉中,制作烘烤型雪莲果薯片,考察雪莲果汁替代水用量百分比、糖添加量、油添加量、盐添加量、烘烤时间、烘烤温度对烘烤型薯片品质的影响.通过响应面试验优化得到烘烤型雪莲果薯片的最佳工艺条件为:马铃薯全粉30 g,白砂糖10 g,油2 g,食盐0.6 g,雪莲果汁36 mL,水4 mL,烘烤温度120℃,烘烤时间16 min.采用该工艺制得的薯片色泽金黄、口感松脆、咸味与甜味比例适中,具有较高的营养和保健价值.     

低糖苹果脯制备工艺研究

以新鲜苹果为原料,在新的制备工艺中用新的、安全、低热量甜味剂取代传统工艺中的蔗糖制备低糖苹果脯。结果表明,最佳的制备工艺条件为切片厚度0.4～0.6 cm,护色硬化过程中氯化钙添加量1.5%,亚硫酸钠添加量0.3%,处理时间2 h;糖液甜味剂质量分数0.75%,糖煮时间15 min;糖煮糖液用于糖渍,糖渍时间40 h;烘烤温度65℃,烘烤时间8 h。新工艺得到的苹果脯感官品质得分93.8±4.5分,总糖含量34.5%;而传统工艺制备的苹果脯感官品质得分88.1±3.2分,总糖含量70.3%。新工艺制备的苹果脯色泽浅黄、均匀一致、块形完整、滋味和气味俱佳,适合糖尿病患者食用。同时,新工艺显著降低了用糖量,有利于环境保护。     

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.     

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.     

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.     

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.     

Breeding apomictic bahiagrass (Paspalum notatum Flügge) with improved turf traits

The development of a turf‐type bahiagrass could have a remarkable impact on the billion‐dollar turf industry in the south‐eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H²) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H² indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation.     

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.     

Genetic constitution and diversity in four narrow endemic redwoods from the family Cupressaceae

The genetic constitution and diversity of four relictual redwoods are discussed in this review. These include monotypic genera of the family Cupressaceae: coast redwood (Sequoia sempervirens), giant sequoia (Sequoiadendron giganteum), dawn redwood (Metasequoia glyptostroboides), and alerce (Fitzroya cupressoides). All four species are narrow endemics, share a number of common phenotypic traits, including red wood, and are threatened species. Fossil history suggests that the ancestors of redwoods probably originated during the Cretaceous and Tertiary periods and flourished thereafter for millions of years. Towards the end of the Tertiary period began their decline and struggle for existence that continued during the subsequent geologic upheavals and climate changes, until the survival of the present-day redwoods in the current restricted locations in the world (USA, China, and South America). Although two species, Sequoiadendron and Metasequoia, are diploids (2n = 22), and the other two are polyploids: Fitzroya a tetraploid (2n = 4x = 44), and Sequoia a hexaploid (2n = 6x = 66); they all share the same basic chromosome number x = 11. The genome size in the hexaploid Sequoia is one of the largest (31,500 MB) in the conifers, while the genome sizes of diploid Metasequoia and Sequoiadendron are about one-third (~10,000 MB) of Sequoia. Genetic diversity in the redwoods is lower than most other gymnosperms, except in Sequoia, which seems to rank near the upper quarter of the coniferous forest trees. Genomic research is sparse in the redwoods, and should be pursued for a better understanding of their genome structure, function, and adaptive genetic diversity.     

Inheritance of fruit colour in a wild Russian red raspberry seedling

Summary A new gene, i, from a self-incompatible wild Russian Rubus idaeus seedling is described. The gene i interacts with the fruit colour gene T, Tii plants having apricot instead of red fruits, and spines, leaves and stems pigmented to varying degrees. A deficit of apricot-fruited seedlings in progenies segregating for i could be explained by linkage between i and the self-incompatibility S locus with a crossover value of approximately 26.7%.Segregations for spine colour in crosses and backcrosses of the Russian seedling with two green-spined (ttII) raspberries selected for their yellow fruit colour, showed that both the latter carried the spine colour intensifier gene P. This suggests that earlier authors were incorrect in attributing the apricot fruit colour developed by some tt plants to a pleiotropic effect of P.     

The induction in vitro of adventitious shoots in Rosa

Summary Adventitious shoots were formed on excised leaves, roots and callus of Rosa persica x xanthina and on excised leaves of R. laevigata and R. wichuraiana on culture media that included BAP and NAA as growth regulators. Shoots formed freely on freshly cultured callus of R. persica x xanthina but their production declined in successive cultures and ceased after twelve weeks. Transplantation to soil was improved by rooting plantlets in cellulose plugs in vitro and transferring plantlets to soil while still in the plugs.