Ding Haiyan, Ali Ahmad, Cheng Zhihui
School of public health, Dali University, Dali 671000, Yunnan, China.
College of Horticulture, Northwest A&F University, Yangling 712100, Shaanxi, China.
Plants (Basel). 2019 Dec 27;9(1):45. doi: 10.3390/plants9010045.
Garlic is considered to have a strong positive effect on the growth and yield of receptors under soil cultivation conditions. However, how this positive promotion is produced by changing the growth environment of the receptors or directly acting on the receptors is still not very clear. The direct influence of co-culturing with different quantities of garlic plants (the control 5, 10, 15, 20) on the growth and biochemical processes of cucumber plants was studied using a hydroponic co-culture system. Different numbers of garlic bulbs inhibited the growth of cucumber plants and increased the production and induction of reactive oxygen species, which accompanied the enhancement of lipid peroxidation and oxidative damage to cucumber. This allelopathic exposure further reduced the chlorophyll contents and photosynthesis rate, and consequently impaired the photosynthetic performance of photosystem II (PSII). Garlic root exudates increased the leaves' carbohydrates accumulation, such as soluble sugar contents and sucrose levels by regulating the activities of metabolismic enzymes; however, no such accumulation was observed in the roots. Our results suggested that garlic root exudates can mediate negative plant-plant interactions and its phytotoxic influence on cucumber plants may have occurred through the application of oxidative stress, which consequently imbalanced the source-to-sink photo-assimilate flow.
大蒜被认为在土壤栽培条件下对受体的生长和产量有很强的积极影响。然而，这种积极促进作用是通过改变受体的生长环境还是直接作用于受体产生的，目前仍不太清楚。利用水培共培养系统研究了与不同数量的大蒜植株（对照5、10、15、20）共培养对黄瓜植株生长和生化过程的直接影响。不同数量的大蒜鳞茎抑制了黄瓜植株的生长，增加了活性氧的产生和诱导，这伴随着黄瓜脂质过氧化作用的增强和氧化损伤。这种化感作用进一步降低了叶绿素含量和光合速率，从而损害了光系统II（PSII）的光合性能。大蒜根系分泌物通过调节代谢酶的活性增加了叶片碳水化合物的积累，如可溶性糖含量和蔗糖水平；然而，在根系中未观察到这种积累。我们的结果表明，大蒜根系分泌物可以介导植物间的负面相互作用，其对黄瓜植株的植物毒性影响可能是通过施加氧化应激而发生的，从而导致源库光合同化物流动失衡。
