Niblack T L, Hussey R S, Boerma H R
J Nematol. 1986 Oct;18(4):444-50.
Greenhouse and field microplot studies were conducted to compare soybean shoot and root growth responses to root penetration by Heterodera glycines (Hg) and Meloidogyne incognita (Mi) individually and in combination. Soybean cultivars Centennial (resistant to Hg and Mi), Braxton (resistant to Mi, susceptible to Hg), and Coker 237 (susceptible to Hg and Mi) were selected for study. In the greenhouse, pot size and number of plants per pot had no effect on Hg or Mi penetration of Coker 237 roots; root weight was higher in the presence of either nematode species compared with the noninoculated controls. In greenhouse studies using a sand or soil medium, and in field microplot studies, each cultivar was grown with increasing initial population densities (Pi) of Hg or Mi. Interactions between Hg and Mi did not affect early plant growth or number of nematodes penetrating roots. Root penetration was the only response related to Pi. Mi penetration was higher in sand than in soil, and higher in the greenhouse than in the field, whereas Hg penetration was similar under all conditions. At 14 days after planting, more second-stage juveniles were present in roots of susceptible than in roots of resistant plants. Roots continued to lengthen in the greenhouse in the presence of either Mi or Hg regardless of host genotype, but only in the presence of Mi in microplots; otherwise, responses in field and greenhouse studies were similar and differed only in magnitude and variability.
进行了温室和田间微区试验，以比较大豆地上部和根部对大豆胞囊线虫（Hg）和南方根结线虫（Mi）单独侵染及混合侵染时根系穿透的生长反应。选择了大豆品种百年（对Hg和Mi均有抗性）、布拉克斯顿（对Mi有抗性，对Hg敏感）和科克237（对Hg和Mi均敏感）进行研究。在温室中，花盆大小和每盆植株数量对科克237根系的Hg或Mi侵染没有影响；与未接种对照相比，在任何一种线虫存在的情况下，根重都更高。在使用沙子或土壤介质的温室试验以及田间微区试验中，每个品种都在Hg或Mi初始种群密度（Pi）增加的条件下种植。Hg和Mi之间的相互作用不影响植株早期生长或穿透根系的线虫数量。根系穿透是与Pi相关的唯一反应。Mi在沙子中的穿透率高于在土壤中的，在温室中的高于在田间的，而Hg在所有条件下的穿透率相似。种植后14天，感病植株根系中的二龄幼虫比抗病植株根系中的多。无论寄主基因型如何，在温室中，在Mi或Hg存在的情况下，根系都继续伸长，但在微区试验中仅在Mi存在的情况下根系伸长；否则，田间和温室试验中的反应相似，只是在程度和变异性上有所不同。
