Construction of Anti-breaking Models of the Main Veins of Flue-cured Tobacco Leaves and Principal Component Analysis

[Objective] This study aimed to explore the related mechanisms of the breaking of flue-cured tobacco leaves. [Method] Anti-breaking models of the main veins of flue-cured tobacco leaves were constructed for principal component analysis on the anti-breaking index, leaf traits and cellulose contents. [Result] The results showed that the growth traits had certain relevance with the cellulose contents while the leaf weight assumed a significant negative correlation with the anti-breaking index, indicating that the heavier the leaf weight was, the weaker the anti-breaking capacity of flue-cured tobacco would be; the cross-sectional area of main veins and the cellulose contents had shown a positive correlation with the anti-breaking index, indicating that the thicker the main vein of flue-cured tobacco was, the higher the cellulose contents would be, and the stronger the anti-breaking capacity of flue-cured tobacco leaves would be. [Conclusion] This study provided theoretical basis and reference to improve tobacco production and enhance the quality of flue-cured tobacco.

茶树根系耐铝促生内生细菌的分离鉴定及其特性研究

茶树喜酸耐铝,且低浓度的铝促进茶树生长,然而其调控机理并不清晰。从耐铝促生菌的角度,探究其可能的原因。以铝处理的茶树根系为材料,经分离鉴定,得到可培养的内生细菌38株,其中厚壁菌门27株,放线菌门11株。从利用1-氨基环丙烷-1-羧酸(ACC)能力、溶磷能力、产铁载体能力和分泌吲哚乙酸(Indole-3-acetic acid,IAA)能力对38株内生细菌进行了探究,结果表明,38株内生细菌都有一种以上的促生能力,其中厚壁菌FBA、FPC以及放线菌AMM、ACP032155等菌株的综合促生能力较好;38株内生细菌在1 mmol·L^(-1) Al^(3+)浓度下均能存活,其中放线菌AME2耐铝能力最强,在8 mmol·L^(-1) Al^(3+)浓度下仍能存活,说明铝能促进茶树耐铝促生菌的生长,从而间接促进茶树的生长,为选育具有显著耐铝促生能力的茶树内生细菌用于茶树的栽培育种奠定基础。

植物病原真菌抑制杂草的活性筛选及菌株CY-H的活性代谢产物

【目的】分离并鉴定具有较好除草活性的植物病原真菌菌株,进一步分离活性化合物,为开发新型生物源除草剂奠定一定的基础。【方法】采用固体培养基接种法分离纯化植物病原真菌,通过形态学特征观察和5.8S rDNA测序鉴定目标菌株;在活性筛选追踪下,对活性组分进行追踪分离及纯化,经波谱分析确定活性单体化合物结构;采用培养皿生物分析法测定活性单体化合物的除草活性及对常见作物的安全性。【结果】茶叶致病菌CY-H具有较好的除草活性,其发酵液对稗草和反枝苋根的抑制率分别为94.6%和77.3%。CY-H被鉴定为间座壳属菌(Diaporthe sp.)。从CY-H菌中分离得到单体化合物CY1被鉴定为cytosporaphenones C。在供试浓度为100μg/mL时,CY1具有较好的抑制反枝苋根的活性,抑制率为57.1%,且其对小麦和油菜的安全性较好,抑制率均在20%左右。【结论】茶叶致病菌CY-H具有开发成微生物源除草剂的潜力。