Utilization of plant defence mechanism against insect pests is considered to be a viable and environmentally safe strategy. In the present study, attempt was made to decipher the morphological and biochemical factors contributing towards resistance/susceptibility of sugarcane genotypes against top borer, Scirpophaga excerptalis Walker, a major insect pest in subtropical region of India. The experiment was conducted at the experimental farm of ICAR-Indian Institute of Sugarcane Research, Lucknow, India. Nine sugarcane varieties, viz. CoS 94257, CoSe 92423, CoPant 97222, CoS 96268, CoS 767, Co 0238, CoLk 94184, CoJ 64 and CoLk 8102 were selected from a diverse group in terms of growth period, degree of pest infestation and other morphological characters. Observations taken on various morphological characters of different sugarcane varieties showed a significant difference on pest incidence. Out of these morphological parameters studied, the thickness of leaf midrib (r = − 0.56) and plant height (r = − 0.44) recorded significant and negative linear correlation with incidence of top borer. However, leaf breadth showed significant and positive correlation (r = 0.52) with incidence of top borer. Amongst the biochemical parameters, such as reducing sugar, total phenol, poly phenol oxidase-specific activity, proteinase inhibitory activity, total soluble protein, nitrogen, phosphorus, potassium contents, correlation study revealed that the reducing sugar was significantly positively correlated (r = 0.77) while proteinase inhibitor activity (r = − 0.82) showed significantly negative correlation. It is noteworthy that the total phenol and polyphenol oxidase activity were significantly positively correlated to proteinase inhibitory activity. The study holds promise for future varietal development programme.

中文翻译：

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甘蔗抗顶生exc蛾的形态学和生化依据的确定

利用植物抵御害虫的防御机制被认为是一种可行且对环境安全的策略。在本研究中，试图破译有助于甘蔗基因型对顶级bore虫Scirpophaga excerptalis的抗性/敏感性的形态和生化因素。沃克，印度亚热带地区的主要害虫。该实验是在印度拉克瑙的ICAR-印度甘蔗研究所的实验农场进行的。九个甘蔗品种，即。CoS 94257，CoSe 92423，CoPant 97222，CoS 96268，CoS 767，Co 0238，CoLk 94184，CoJ 64和CoLk 8102从生长时期，害虫侵染程度和其他形态特征方面进行了选择。对不同甘蔗品种的各种形态特征进行的观察显示，害虫发生率有显着差异。在研究的这些形态学参数中，叶片中脉的厚度（r  = − 0.56）和植物高度（r = − 0.44）记录了与上bore钻的发生率呈显着负相关。然而，叶宽 与顶bore的发生率呈显着正相关（r = 0.52）。在还原糖，总酚，多酚氧化酶比活性，蛋白酶抑制活性，总可溶性蛋白，氮，磷，钾含量等生化参数中，相关性研究表明，还原糖呈显着正相关（r  = 0.77）。 ）而蛋白酶抑制剂活性（r = − 0.82）显示出显着的负相关。值得注意的是，总酚和多酚氧化酶活性与蛋白酶抑制活性显着正相关。该研究对未来的品种开发计划有希望。