Crosses between two subspecies of bay scallop Argopecten irradians and heterosis for yield traits at harvest

In order to improve the yield of bay scallop Argopecten irradians by exploiting geographic subspecies heterosis, crosses between and within two subspecies, the northern A. i. irradians (Lamarck) and the southern A. i. concentricus (Say), were created and the offspring were cultured under the same environmental conditions. The two parental populations were collected from Bohai Bay in northern China and Beibu Bay in southern China, which were distinct in particular shell colours. The results indicated that the shell colour of bay scallop was inheritable and could be used as a morphological mark to distinguish hybrid and purebred individuals. At harvest, hybrid offspring always produced a significantly higher yield than purebred offspring. Positive heterosis was achieved for shell length, shell height, shell width, total weight and adductor weight, which was 5.02, 5.22, 3.88, 7.53 and 9.47 respectively. Hybrid gain was 10.86% for shell length, 10.48% for shell height, 9.77% for shell width, 34.90% for total weight and 41.69% for adductor weight, respectively, and all were significantly >5%. The present study reveals that it is effective for improving yield by hybridization between different geographic subspecies in the bay scallop.     

L-半胱氨酸—植酸缔合显色体系的研究

植酸和半胱氨酸的显色反应。在ｐＨ＝１００的ＮＨ３－ＮＨ４Ｃｌ缓冲体系中,植酸与半胱氨酸可以形成稳定的缔合物,缔合物的最大吸收波长为５７０ｎｍ。该体系操作方便、灵敏度高,具有很好的显色可逆性,其它氨基酸不干扰半胱氨酸的鉴定,用于混合样品中半胱氨酸的定性鉴定,结果满意。     

Hand-held chlorophyll meter: a promising tool to assess the nitrogen status of potato foliage

Summary A field experiment with potato (Solanum tuberosum L., cv. Vebeca) was conducted on a sandy soil near Wageningen (52° North) in 1992. The treatments included a zero-nitrogen control and combinations of three amounts of nitrogen, viz. 110, 180 and 250 kg N ha⁻¹, and splitting of the N dose in one (early May), two (early May and June) or three (early May, June, July) applications. The chlorophyll content of the uppermost fully grown leaves was assessed with a SPAD-502 chlorophyll meter (Minolta, Osaka, Japan) throughout the season. The pattern of change with time in SPAd-values differed between treatments. SPAD-502 readings correlated well with laboratory measurements of the chlorophyll content and with the nitrogen concentration in leaves (r ²>0.95). Data on the nitrate concentration in petiole sap (included as a reference) showed that this variable responded much more to split nitrogen applications than the SPAD-value. Future research will need to consider other factors which may affect the chlorophyll content of the foliage.     

微波高压快速消解-紫外分光光度法测定南阳彩色小麦中的微量元素硒

以南阳灰麦、紫麦、蓝麦为材料,采用微波高压快速消解-紫外分光光度法测定了样品中微量元素硒的含量。结果表明:南阳彩色小麦中硒含量为13.37~21.95 mg/kg(干基),3ε32为1.4×104,标准曲线的相关系数r为0.999 7,加标回收率为100.6%~105.7%,RSD为4.4%,因此该法具有灵敏度高、稳定性好、工作曲线线性关系好的显著优点,结果令人满意。     

玉米单交种Sc704杂交率室内鉴定方法的研究

根据玉米种子的籽粒和幼芽的品种性状不同,提出了单交玉米Sc7004杂交率的室内鉴定方法。     

Effect of controlled atmosphere,temperature and cultivar on sprouting and processing quality of stored potatoes

Summary Three crisping potato cultivars, Record, Saturna and Hermes, were stored at 5 or 10°C in gas mixtures of either 0.5% CO₂ and 21.0% O₂ (control) or 9.4, 6.4, 3.6 or 0.4% CO₂ all combined with 3.6% O₂. There was almost complete sprout inhibition, low weight loss and maintenance of a healthy skin for all cultivars stored in 9.4% CO₂ with 3.6% O₂ at 5°C for 25 weeks. When tubers from this treatment were stored for a further 20 weeks in air at 5°C the skin remained healthy and they did not sprout. The fry colour of crisps made from these potatoes was darker than the industry standard but when they were reconditioned, tubers of cv. Saturna produced crisps of an acceptable fry colour while crisps from the other two cultivars remained too dark. Reducing sugar levels were related to fry colour both after storage and after reconditioning. The other gas combinations and the controls did not have the same effect on sprouting and none of the controlled atmosphere treatments controlled sprouting at 10°C.     

鱼腥草调味粉的研制

以新鲜鱼腥草为原料,研究了鱼腥草调味粉的加工工艺,重点讨论了护色处理条件。结果表明,将洗净的鱼腥草放入浓度为0.1%柠檬酸溶液中,在100℃下烫漂1min,然后在0.1%的NaHSO3溶液中护色处理30min,经漂洗后在70℃下真空恒温干燥6.5h,再用粉碎机粉碎,最后经包装可获得品质理想的产品。该产品不仅具有鱼腥草特有的天然风味,还有清火解暑、保健美容等功效。     

马铃薯块茎蒸煮品质、质构特性及加工型品系筛选

【目的】蒸煮是马铃薯食用最主要的加工方式,马铃薯商业化加工过程中需要对蒸煮加工的品质性状进行定量化分析和分类。根据商业化加工的需求在品种选育中进行蒸煮品质性状的早期选择和筛选,确定蒸煮加工型品种的品质性状特征和相关参数,同时从现有品种和品系中根据商业化加工参数筛选适合不同用途需求的蒸煮品种,是提高蒸煮加工型品种选育效率和方法的有效手段,为制定蒸煮加工型品种选育目标提供基础。【方法】在对马铃薯品种和品系的块茎产量、块茎大小、薯型、薯肉颜色、芽眼深度、抗病性和商品率的初步选择基础上,筛选14个品种和品系进行蒸煮试验,在普通蒸锅中放入块茎蒸煮25 min,蒸熟后,在室温环境冷却20 min,7 d后,分别对蒸煮前后块茎色泽变化、蒸煮前后块茎硬度、蒸煮前后软化度进行测定。同时测定这些品种和品系的干物质含量、淀粉含量、蔗糖含量、葡萄糖含量、果糖含量、游离氨基酸含量、绿原酸含量、柠檬酸含量、抗坏血酸含量,分析以上成分在蒸煮加工过程中变化对品种和品系块茎的风味、色泽和质构特性的影响,确定蒸煮加工型品种的加工参数。【结果】选育蒸煮加工型马铃薯品种,首先考虑田间综合农艺性状要能够满足商业化生产与加工过程工艺流程和加工机械要求。块茎还原糖含量是影响蒸煮风味中甜度的主要因素,含量应控制在0.4%以下。游离氨基酸含量与蒸煮风味中鲜味有关,14个品种和品系的氨基酸含量差别还不能构成显著的风味差别,所有品种和品系的氨基酸含量介于30—70μmol。块茎品种风味构成中的苦味来源主要是糖苷碱含量,蒸煮加工型品种的糖苷碱含量应控制在150 mg·kg~(-1)以下。蒸煮后冷却20 min块茎色泽变化值和蒸煮后7 d的色泽变化值ΔE差值是衡量蒸煮加工型品种色泽变化的重要参数。块茎蒸煮前后的软化度是衡量蒸煮加工型品种质地变化的重要参数。【结论】14个品种和品系块茎蒸煮后的风味、色泽变化、质构特性变化是判定蒸煮加工型品种的重要参数,通过对这些参数的全面分析表明,品种Burbank、Shepody和品系0724-58、0712-66是蒸煮后软化度比较高的品种和品系,而0744-8和0722-26是蒸煮后软化度比较低的品系。     

Ge-Gallein-CPC显色体系的研究

本文研究了在表面活性剂氯化十六烷基吡啶（ＣＰＣ） 存在下, 以茜素紫为显色剂测定微量锗的反应条件和络合物组成。试验表明, 络合物在５４０ｎｍ 处有最大吸收, 方法灵敏可靠。在试验酸度下（ｐＨ＝ １－８～２－４） , 大部分常见元素不干扰测定, 适合于煤灰及合金中微量锗的测定