Manachini B, Landi S, Tomasini V
Istituto di Entomologia Agraria - Università degli Studi di Milano, Italy.
Commun Agric Appl Biol Sci. 2005;70(4):927-35.
Few data is available on the nematodes found in Brassicaceae, except for the most important plant parasite. However, studying the structure of nematofauna could be an important database for the soil quality and in order to assess the effects of future disturbance. This is particularly important considering that the diffusion of the canola crop in the world is increasing because of its use as a bio-diesel. Very diffused is also the Bt variety of oil seed rape, and, in this case, the study of the impact on the soil health and on bio-diversity is essential. In this research we have analyzed the nematode community, used as a bio-indicator of the soil condition. The nematofauna found in canola (Brassica napus var. oleifera) fields located in Southern Italy (Metaponto - MT) was investigated. The nematode community was studied considering its abundance, genus composition and trophic structure. Maturity and biodiversity indices were also calculated. A total of 5286 nematodes were extracted. They belong to 14 families and 24 genera. Bacterial and fungal feeders, 50.18% and 42.90% of the total respectively, dominated the trophic structure. Aphelencus is the most abundant genus (23.71%) followed by Acrobeloides (20.49%) and Aphelencoides (19.18%). Among plant feeders (6.59%), Pratylenchus is the dominant genus (2.20%) and Tylenchidae the main family (3.54%). No infestation of Meloidogyne, Heterodera or Naboccus, important plant-parasitic nematodes of canola crops, was recorded. Other important phytophagous were Helycotylenchus (0.5%), Trichotylenchus (0.5%) and Filenchus (0.9%). All of them had an abundance level below injury level. The indices of biodiversity are rather low (H'=0.93, J'=0.67), as is typical for agro ecosystems. However, the nematofauna community is quite well structured (N2=6.31, D=0.16) and the maturity index rather high (EMI=1.94). These values demonstrate that oilseed rape has a lower impact on the soil compared to other crop systems and that it could be taken into consideration for crop rotation programs. Canola could follow other more stressful crops, trying to maintain soil equilibrium.
除了最重要的植物寄生虫外，关于十字花科植物中发现的线虫的数据很少。然而，研究线虫动物区系的结构可能是土壤质量的一个重要数据库，以便评估未来干扰的影响。考虑到油菜作为生物柴油的用途在世界范围内的种植面积不断增加，这一点尤为重要。转基因抗虫（Bt）油菜品种也非常普遍，在这种情况下，研究其对土壤健康和生物多样性的影响至关重要。在本研究中，我们分析了作为土壤状况生物指标的线虫群落。对位于意大利南部（梅塔蓬托 - MT）的油菜（Brassica napus var. oleifera）田中的线虫动物区系进行了调查。从线虫的丰度、属的组成和营养结构方面对其群落进行了研究。还计算了成熟度和生物多样性指数。共提取了5286条线虫。它们属于14个科和24个属。细菌和真菌取食者分别占总数的50.18%和42.90%，在营养结构中占主导地位。滑刃线虫属是最丰富的属（23.71%），其次是拟小杆线虫属（20.49%）和细杆线虫属（19.18%）。在植物取食者中（6.59%），短体线虫属是优势属（2.20%），垫刃线虫科是主要科（3.54%）。未记录到油菜作物重要的植物寄生线虫根结线虫属、异皮线虫属或矮化线虫属的侵染。其他重要的植食性线虫有螺旋线虫属（0.5%）、盘旋线虫属（0.5%）和丝尾垫刃线虫属（0.9%）。它们的丰度水平均低于损伤水平。生物多样性指数相当低（H' = 0.93，J' = 0.67），这是农业生态系统的典型特征。然而，线虫动物区系群落结构相当良好（N2 = 6.31，D = 0.16），成熟度指数相当高（EMI = 1.94）。这些值表明，与其他作物系统相比，油菜对土壤的影响较小，可考虑将其纳入轮作计划。油菜可以种植在其他压力更大的作物之后，以维持土壤平衡。
