Abstract：
Chitosan is an environmentally friendly natural substance that is used in crop disease management as an alternative to chemical pesticides. A significant issue restricting output in Egypt is root rot, which is a disease, caused by Rhizoctonia solani. Therefore, a greenhouse experiment was conducted to assess the effects of R. solani on 60-day-old tomato plants under fungal infection and to determine the antifungal activity of chitosan and Rizolax T fungicide against the pathogenic fungus. The findings demonstrated that 4 g/L of chitosan seed application completely obstructed the radial mycelial growth of R. solani and decreased the disease severity. Pathogenic infection significantly decreased morphological characteristics and total chlorophyll but significantly increased carotenoid, total thiol, non-protein thiol, protein thiol, antioxidant enzymes, oxidative stress, total phenolic, total flavonoid, and isoflavone compared to healthy plants. Tomato plants treated with chitosan exhibited lower rates of oxidative stress, but higher levels of all previously mentioned parameters compared to untreated infected plants. The number and molecular mass of protein banding patterns varied in all treated tomato plants as compared to the healthy control. There are 42 bands in the treatments, and their polymorphism rate is 69.55%. Moreover, the number and density of α- and β-esterase, and peroxidase isozymes in treated tomato plants exhibited varied responses. Moreover, in treated and control plants, chitosan treatment raised the expression levels of phenylalanine ammonia-lyase, pathogenesis-related protein-1, β-1,3-glucanases and chitinase. In conclusions, chitosan reduces R. solani infection by controlling the biochemical and molecular mechanisms in tomato plants during infection.
摘要：
壳聚糖是一种环境友好的天然物质，用于作物病害管理，作为化学农药的替代品。埃及限制产量的一个重要问题是根腐病，这是一种疾病，由根瘤菌引起的。因此,进行了温室实验，以评估R.solani对真菌感染下60日龄番茄植物的影响，并确定壳聚糖和RizolaxT杀菌剂对病原真菌的抗真菌活性。研究结果表明，4g/L壳聚糖种子的施用完全阻碍了R.solani的放射状菌丝生长，并降低了疾病的严重程度。病原感染显著降低了形态特征和叶绿素总量,但显著增加了类胡萝卜素,总硫醇，非蛋白质硫醇，蛋白质硫醇，抗氧化酶，氧化应激，总酚,总黄酮，和异黄酮与健康植物相比。用壳聚糖处理的番茄植物表现出较低的氧化应激率，但与未经处理的受感染植物相比，所有先前提到的参数水平更高。与健康对照相比，所有处理的番茄植物的蛋白质条带模式的数量和分子量都不同。治疗中有42个带，多态性率为69.55%。此外，α-和β-酯酶的数量和密度，处理过的番茄植物中的过氧化物酶同工酶表现出不同的响应。此外，在处理和对照植物中，壳聚糖处理提高了苯丙氨酸解氨酶的表达水平，发病相关蛋白-1，β-1,3-葡聚糖酶和几丁质酶。在结论中，壳聚糖通过控制感染过程中番茄植株的生化和分子机制来减少枯萎病的感染。
