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11.
Apple breeding is usually done to produce higher quality apples. We crossed two late ripening high quality apple cultivars (i.e., Golden Smoothie and Red Spur) as maternal parents with two Iranian domestic early ripening apple cultivars (i.e., Golab-e Kohanz and Shafi Abadi) as pollen parents in 2005 to breed new early ripening apple cultivars. We then measured qualitative and quantitative traits of 360 off spring during 2010 and 2011. Results of recorded traits on the 5th and 6th year of growth of the progeny showed that during two evaluation years, flowering and fruit ripening time, titrable acidity, SSC/acid ratio, and fruit weight had the highest coefficients of phenotypic variations. Progenies were classified in three groups: early, mid, and late ripening. Some of the selected progeny were better than their early ripening parental cultivars being earlier in the ripening, with larger fruit size and better texture and flavor. Genotypes A31, A32, I5, I23, and I57 were in the early ripening category, B11 and A34 were in the middle, and B77 and E21 were in the late ripening categories. These characteristics were considered to present an improvement.  相似文献   
12.
苹果压缩特性的研究   总被引:2,自引:0,他引:2  
通过苹果的压缩试验,测定和分析了其力-变形曲线的特性。结果表明,压缩时的加载速率与压头型式影响生物屈服力、破裂力与变形量的大小;在一定条件和范围内,苹果硬度与压缩曲线初始区段的斜率线性显著相关,且苹果的机械损伤与其变形量有关。  相似文献   
13.
报道2003年至2004年10个引进亚麻品种在云南省8个试验点的纤维产量和品质测定结果。3个国外品种的长麻率、总麻率、纤维产量明显高于国内品种;方差分析显示,不同地点间、不同品种间纤维产量差异显著。10个亚麻品种的平均分裂度变幅为344~407公支,平均断裂强力变幅为200~248 N,平均可挠度介于49.6~56.6 mm;同一品质指标在不同试点的变幅较大。方差分析结果表明,正麻品种间的纤维品质差异不显著,地点间的纤维品质差异显著。  相似文献   
14.
风化作用对沟谷型泥石流发育环境的影响研究   总被引:1,自引:0,他引:1  
地质条件是泥石流发育环境的三大条件之一,其主要作用是为泥石流提供固体物源。风化作用对产生泥石流固体物源的影响很大。以岩石的坚固系数为基础,研究了物理及化学风化对形成泥石流固体物源的影响。研究结果表明:(1)物理风化是形成泥石流物源的主要原因,冰劈作用往往造成强烈的物理风化,有利于泥石流的发育(2)化学风化不直接提供固体物源,但碳酸根离子的存在使化学风化不利于泥石流的发育。研究得出岩石坚固系数的物理风化和化学风化修正方法,最终得到形成泥石流的地质因子。形成泥石流的地质因子在汶川地震影响区内判别泥石流的暴发与否的应用研究中取得了较好的结果。  相似文献   
15.
The gluten polymerization behavior, water content, starch crystallinity and firmness of Chinese steamed bread made from frozen dough were investigated and their correlations were also established in this study. The decreased degree of gluten polymerization in steamed bread was observed by the enhanced SDS-extractable proteins (SDSEPs) upon frozen storage. Less incorporation of glutenin in the glutenin–gliadin crosslinking of steamed bread mainly contributed to the decreased degree of gluten polymerization. The decreased moisture of steamed bread had a significant negative correlation with the sublimated water in frozen dough (r = −0.8850, P < 0.01). Frozen storage also induced an increase in starch crystallinity and bread firmness. A multiple linear regression model with SDS-extractable proteins, water content and melting enthalpy of starch crystals of steamed bread accounted for 86% of the variance in the natural logarithm of firmness and further revealed that starch crystallinity mainly contributed to bread firmness.  相似文献   
16.
床垫作为睡眠的平台,其支撑性能对人体健康和睡眠舒适性有着重要的影响。在定量化研究床垫软硬度的基础上,利用体压分布测试,通过软硬度适宜的床垫与硬度较大的床垫进行对比分析,研究床垫软硬度对人体舒适性的影响。结果表明:(1)软硬度适宜的床垫有利于人-床界面压力的分散性,有利于人体腰部支撑;(2)适宜于男性受试者的床垫的软硬度小于适宜于女性受试者的床垫软硬度。  相似文献   
17.
延迟和缩短苹果气调处理时间对贮藏效果的影响   总被引:3,自引:1,他引:3  
 以新红星苹果为试材探讨延迟和缩短低氧气调新组合(10 ℃, 2 %O2 + 7. 5 %CO2) 处理时间对其贮藏效果的影响。结果表明, 贮藏123 d 时, 冷藏对照(0 ℃, 空气) 和常规气调处理(0 ℃, 3 %O2 + 3 %CO2) 果实的虎皮病果率分别为25. 6 %和1. 02 % , 果肉硬度分别为5. 79 和6. 52 kg/ cm2, 而低氧新组合处理无虎皮病, 果肉硬度(6. 63 kg/ cm2) 显著高于冷藏对照, 而与常规气调处理无显著差异。10 ℃空气中放15 d 后再用低氧新组合处理108 d 的果实虎皮病果率6. 67 % , 果肉硬度(4. 8 kg/ cm2) 显著低于冷藏对照和常规气调处理。这些结果说明果实采后及时进行低氧气调处理是必要的。冷藏对照、常规气调处理和在10 ℃下低氧新组合处理123 d 的果实再于0 ℃空气中放58 d , 其虎皮病果率分别为46. 9 %、36. 4 %和0 , 果肉硬度分别为5. 28 、5. 21 和4. 5 kg/ cm2。在10 ℃下低氧新组合处理96 d 再冷藏的苹果, 在贮后50 d 时无虎皮病果, 果肉硬度为4. 67 kg/ cm2 。综合来看, 计划贮期约5 个月时, 10 ℃下低氧新组合处理的时间可由4 个月缩短为3. 3 个月。低氧气调新组合处理的苹果在气调期间α2法尼烯和共轭三烯的形成受到显著抑制。  相似文献   
18.
基于高光谱图像的蓝莓糖度和硬度无损测量   总被引:6,自引:3,他引:3  
李瑞  傅隆生 《农业工程学报》2017,33(Z1):362-366
为了对蓝莓硬度和糖度进行无损检测,采用近红外光谱仪(900~1700 nm)分别对490个"蓝丰"蓝莓的果柄侧和花萼侧进行高光谱成像,并测量整个果实的硬度和糖度。应用偏最小二乘回归法分别对果柄侧、花萼侧和整个果实的平均光谱建立硬度和糖度预测模型。试验结果表明,蓝莓硬度呈双峰分布,表明实际生产中有望分为2类;蓝莓糖度呈正态分布;硬度和糖度的相关性仅为?0.15,说明不能通过二者之中的任何一个来估计和评价另一个。采用整个果实的平均光谱数据建模效果最好,硬度的校正集相关系数RC和验证集相关系数RV达到0.911和0.871,糖度的为0.891和0.774,但主成分数都有所增加。结果表明,采用高光谱技术对蓝莓硬度和糖度进行快速、无损检测是可行的。  相似文献   
19.
《Journal of plant nutrition》2013,36(11):1991-2006
Abstract

The response of “Jonathan” apple trees (Malus domestica, Borkh.) grafted on EMLA 111 to frequent application of calcium chloride (CaCl2) was studied at Topeka, Emporia, and Conway Springs, Kansas, orchards in 2002. Trees were sprayed one to eight times with foliar applications of calcium chloride at the rate of 8.971 kg ha?1. First spray was made when fruits were 1.4, 0.9, and 1.6 cm diameter at Topeka, Emporia, and Conway Springs, respectively. More than six applications of CaCl2 improved fruit quality at harvest. Improvement included an increase in fruit weight, size, appearance, skin redness, and reduction of scald incidents. Although CaCl2 applications had no effect on percent of soluble solids, the ratio of soluble solid content to titratable acidity was increased by frequent CaCl2 application. Fruit skin redness was the most improved quality of “Jonathan” apple as the result of CaCl2 applications. No symptoms of fruit russetting or leaf scalding resulting from frequent CaCl2 application were observed. Increase in fruit quality was attributed to a linear increase in Ca concentrations in fruit and leaf tissues. Increase in Ca concentrations in fruit and leaf tissues of treated trees coincided with increases in potassium (K), magnesium (Mg), phosphorus (P), and nitrogen (N) concentrations compared with untreated control trees. Potassium, Mg, P, and N were correlated with fruit quality as much as, or in some cases more than, Ca. This information suggests that changes in mineral balance with CaCl2 applications contributed to improvement of fruit quality and is evidence that frequent Ca application improved “Jonathan” apple quality in Kansas.  相似文献   
20.
Little is known regarding the impact of calcium chloride applications during growth and development on tomato postharvest quality. This trial investigated supplemental calcium chloride applications on yield, nutrient content, texture, and postharvest quality of tomato fruit. Calcium (Ca) nutrient solution concentrations were: 60, 180, and 360 mg·L?1 calcium, while foliar applications were (0, 1, and 2% calcium chloride w/v). Plants grown with 60 mg·L?1 Ca had a high incidence of blossom end rot, which was not affected by calcium chloride sprays. Fruit nutrient concentrations were affected by calcium delivered through the nutrient solution. As fruit cluster position increased, fruit nutrient concentrations significantly decreased. Foliar calcium chloride sprays affected fruit soluble solids content and dry weight, but did not affect texture. Pericarp elasticity increased concomitantly with calcium in the nutrient solution. Postharvest disease incidence was not affected by calcium treatment, though weight loss during storage was negatively affected by calcium chloride sprays.  相似文献   
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