南方根结线虫初始种群密度对不同抗性番茄品种生长的影响

Effect of initial population densities of Meloidogyne incognita on growth of susceptible and resistant tomato plants

在温室条件下,通过盆栽试验,测试了土壤根结线虫初始种群密度对番茄感病品种‘硕源东洋’和抗病品种‘仙客6号’不同生长期的根部危害程度和植株生长的影响。结果显示:南方根结线虫对不同抗性番茄品种的危害均随着土壤线虫密度的增加和生长期的延长而逐渐加重,但感病品种根部形成的卵囊数量、病情指数和最终线虫密度均显著高于抗病品种。依据Seinhorst模型,分别以茎叶鲜重和茎叶干重为指标,确定感病品种和抗病品种对根结线虫的最低忍耐值T分别为4.3N/mL和3.9N/mL,相对最小产量m分别为0.09和0.39,表明番茄感病品种和抗病品种的最低忍耐值没有显著性差异,但抗病品种的相对最小产量高于感病品种,表现较强的抗病性。

Glasshouse pot experiments were conducted at （25 ±3） ℃ to investigate the relationship between the initial population densities of Meloidogyne incognita and the growth of susceptible ＇Shuoyuandongyang＇ and resistant ＇Xianke No. 6＇ tomato plants. The results showed that the damage was severely with the increasing densities of M. incognita and the growing stage for both of resistant cultivar and susceptible cultivar. The number of egg mass, disease index and final nematode population densities in susceptible cultivar plants were higher than those in resistant cultivar plants. The tolerance limit was calculated based on the relationship between the fresh or dry weigh and the nematode densities with the Seinhorst model. The final tolerance limit value of the susceptible and the resistant tomato to M. incognita was 4.3 and 3.9 nematodes per milliliter soil, respectively. The minimum relative yield of the susceptible and the resistant tomato to M. incognita was 0.09 and 0.39, respectively. The tolerance limit values of the susceptible and resistant tomato cultivars were close to each other, but the mini- mum relative yield of resistant tomato was sig suggesting that the resistant tomato had high resistance to the disease.