香蕉和大蕉果实在不同温度下催熟后的色泽变化

 香蕉和大蕉在20℃和30℃条件下果实催熟期间果皮色泽及几种色素含量的变化结果表明: 在20℃下香蕉、大蕉具有正常的呼吸和乙烯释放高峰, 果皮色泽由绿转黄, 叶绿素含量逐渐降低, 类胡萝卜素含量逐渐上升; 但在30℃下, 香蕉果实虽然出现了正常的呼吸和乙烯释放的高峰, 但叶绿素的降解受到了一定的抑制, 果皮不能正常褪绿, 出现了青皮熟现象, 而大蕉却能正常褪绿转黄。     

不同薄膜覆盖对冬季茶树扦插发根率的影响

在扦插苗圃用不同颜色的塑料薄膜进行覆盖 ,观察地温、气温和空气湿度的变化对扦插苗发根的影响。结果表明 ,用薄膜覆盖的茶苗发根率比对照高十几倍 ,各种薄膜处理的发根效果以黄色膜 >红色膜 >黑色膜 >白色膜 >蓝色膜 ,地温和湿度与茶苗发根的相关系数显著。     

白菜型油菜种皮和种胚硫甙总量及其分量分析

试验结果表明,不论硫甙含量高低,白菜型黑籽油菜皮壳率约为19％,黄籽为14％。普通油菜的种胚和种皮的硫甙含量分别占种子硫甙含量的96％和4％,优质油菜的种胚和种皮的硫甙含量分别占种子硫甙含量的89％和11％。种子和种胚中以3—丁烯基硫甙为主,种皮中则以3—了烯基硫甙和2—羟基—3—丁烯基硫甙为主。     

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.     

谷子黄叶色突变体光合特性研究

为解析谷子黄叶色突变体高光合特性机理,以野生型豫谷1号为对照,分析了谷子全生育期黄叶色突变体ylm-1和ylm-2的光合色素、光合速率、气孔特性、荧光参数、光合关键酶活性和产量性状。结果表明,突变体光合色素含量为野生型豫谷1号的50%~60%,强光下突变体光合速率(Pn)较野生型显著提高,且无明显的“午休睡眠现象”;ylm-1和ylm-2气孔导度(Gs)显著增加。荧光参数结果显示,与野生型相比,突变体的光能利用效率和转化效率明显增加,光合关键酶1,5二磷酸核酮糖羧化酶(Rubisco)活性明显降低,而ylm-1和ylm-2磷酸烯醇式丙酮酸羧化酶(PEPCase)和苹果酸酶(NADP-ME)活性分别增加了23.3%、24.4%和12.9%、15.5%。产量相关性状分析表明,突变体单穗质量、穗粒质量及千粒质量较野生型显著增加。本研究结果为谷子高光效及分子标记辅助选择育种提供了重要的理论依据。     

半番鸭及其母本AFLP标记与羽色性状相关分析

为分析AFLP标记与羽色性状的相关性,本研究在利用64对引物对黑、白羽半番鸭及其母本（闽农白鸭和莆田黒鸭）池DNA进行AFLP标记全面筛查,获得3个差异带(H1、H2和H3)的基础上,再次利用AFLP技术分别对上述4个群体的全部个体进行检测,进一步验证这3个AFLP标记是否为半番鸭白羽性状特有或与其相关。结果发现,H1、H2和H3这3个差异带在黑羽半番鸭和莆田黒鸭中均不表达;在白羽半番鸭中以H1的频率最高达89%,H3的频率最低只有52%;在闽农白鸭中H1的频率也达到81%。以此表明差异带H1可作为半番鸭白羽性状辅助选择的一个分子标记。     

半番鸭白羽性状AFLP标记的筛选与分离

采用EcoRⅠ/TaqⅠ系列的64对引物对半番鸭羽色性状进行AFLP标记筛查,结果表明：经重复试验,最终获得3个白羽性状特异片段,它们分别由引物组合E-AAG/T-AAC、E-AAG/T-AGT、E-AGC/T-AAT扩增得到。对这3个白羽性状特有的AFLP片段测序分析,其中引物组合E-AGC/T-AAT差异片段序列与鸡的WAG-9005基因全序列相似性为73%;引物组合E-AAG/T-AAC和引物组合E-AAG/T-AGT两个差异片段与数据库中相似性较低,推测可能是新的与半番鸭白羽性状相关的基因片段。     

Tagging quantitative trait loci for dormancy, tuber shape, regularity of tuber shape, eye depth and flesh colour in diploid potato originated from six Solanum species

Potato breeding aims at breeding diversified cultivars not only suitable for different purposes, but also resistant to diseases, such as late blight caused by Phytophthora infestans , which is a major constraint in potato production. Resistance to P. infestans has been previously introduced into the diploid hybrid population 98-21 from Solanum verrucosum and Solanum microdontum . In the present study, we assessed the segregation of tuber dormancy, tuber shape, regularity of tuber shape, eye depth and flesh colour in this population. Quantitative Trait Loci (QTLs) affecting these important quality traits were tagged using the genetic map developed for this population to locate QTLs for late blight resistance. The most prominent QTL for dormancy was detected on chromosome II and explained 7.1% of the variance. The most important QTLs for tuber eye depth, flesh colour, shape and shape regularity were identified on chromosomes X ( R ² = 14.7%), IV ( R ² = 5.8%), II ( R ² = 8.0%) and III ( R ² = 10.4%) respectively. All traits were also affected by minor QTLs. The obtained results improve our understanding of the inheritance of traits relevant for variety development in potato.     

湄江翠片加工工艺中香气与色泽的相关性初探

详细介绍了湄江翠片茶各种工艺组合,并根据制茶原理,分析了制茶因子对湄江翠片的品质影响,通过分析对比,找出了湄江翠片比较合理的工艺组合。     

桃蚜体色生物型的研究

本文根据桃蚜Myzus persicae(Sulzer)的体色将其分成黄绿色型、红色型和褐色型等三种体色生物型。三种体色生物型比较稳定,可能是由遗传基因控制的。测定表明,各体色生物型不仅体色有差别而且形态上也有一定区别。三种生物型对温度的适应性不同,以褐色型最为抗高温、抗低温,但在适温15—25℃的范围内γm比其它两型都要小;相反,黄绿色型对温度的适应范围最小,但在适温范围内γm最大;而红色型则居于两者之间。