PDF(Pubmed)
Abstract：
BACKGROUND: Drought stress is currently the primary abiotic stress factor for crop loss worldwide. Although drought stress reduces the crop yield significantly, species and genotypes differ in their stress response; some tolerate the stress effect while others not. In several systems, it has been shown that, some of the beneficial soil microbes ameliorate the stress effect and thereby, minimizing yield losses under stress conditions. Realizing the importance of beneficial soil microbes, a field experiment was conducted to study the effect of selected microbial inoculants namely, N-fixing bacteria, Bradyrhizobium liaoningense and P-supplying arbuscular mycorrhizal fungus, Ambispora leptoticha on growth and performance of a drought susceptible and high yielding soybean cultivar, MAUS 2 under drought condition.
RESULTS: Drought stress imposed during flowering and pod filling stages showed that, dual inoculation consisting of B. liaoningense and A. leptoticha improved the physiological and biometric characteristics including nutrient uptake and yield under drought conditions. Inoculated plants showed an increased number of pods and pod weight per plant by 19% and 34% respectively, while the number of seeds and seed weight per plant increased by 17% and 32% respectively over un-inoculated plants under drought stress condition. Further, the inoculated plants showed higher chlorophyll and osmolyte content, higher detoxifying enzyme activity, and higher cell viability because of less membrane damage compared to un-inoculated plants under stress condition. In addition, they also showed higher water use efficiency coupled with more nutrients accumulation besides exhibiting higher load of beneficial microbes.
CONCLUSIONS: Dual inoculation of soybean plants with beneficial microbes would alleviate the drought stress effects, thereby allowing normal plants\' growth under stress condition. The study therefore, infers that AM fungal and rhizobia inoculation seems to be necessary when soybean is to be cultivated under drought or water limiting conditions.
RESULTS: Drought stress imposed during flowering and pod filling stages showed that, dual inoculation consisting of B. liaoningense and A. leptoticha improved the physiological and biometric characteristics including nutrient uptake and yield under drought conditions. Inoculated plants showed an increased number of pods and pod weight per plant by 19% and 34% respectively, while the number of seeds and seed weight per plant increased by 17% and 32% respectively over un-inoculated plants under drought stress condition. Further, the inoculated plants showed higher chlorophyll and osmolyte content, higher detoxifying enzyme activity, and higher cell viability because of less membrane damage compared to un-inoculated plants under stress condition. In addition, they also showed higher water use efficiency coupled with more nutrients accumulation besides exhibiting higher load of beneficial microbes.
CONCLUSIONS: Dual inoculation of soybean plants with beneficial microbes would alleviate the drought stress effects, thereby allowing normal plants\' growth under stress condition. The study therefore, infers that AM fungal and rhizobia inoculation seems to be necessary when soybean is to be cultivated under drought or water limiting conditions.
摘要：
背景：干旱胁迫是目前全球作物损失的主要非生物胁迫因素。虽然干旱胁迫会显著降低作物产量，物种和基因型在应激反应方面有所不同；有些耐受胁迫效应，而另一些则不耐受。在几个系统中，已经表明，一些有益的土壤微生物改善了胁迫效应，在应力条件下最大限度地减少产量损失。意识到有益土壤微生物的重要性，进行了一项田间试验，以研究选定的微生物接种剂的效果，即，N-固定细菌,辽宁缓生根瘤菌和供磷丛枝菌根真菌，Ambisporaleptotitcha对干旱敏感和高产大豆品种的生长和性能的影响，干旱条件下的MAUS2。
结果：在开花期和豆荚灌浆期施加的干旱胁迫表明，由B.liaoningense和A.leptitcha组成的双重接种改善了生理和生物特征，包括干旱条件下的养分吸收和产量。接种的植物显示每株植物的豆荚数量和豆荚重量分别增加了19％和34％，在干旱胁迫条件下，每株植物的种子数量和种子重量分别比未接种植物增加了17％和32％。Further,接种的植物表现出更高的叶绿素和渗透压物质含量，更高的解毒酶活性，在胁迫条件下，与未接种的植物相比，由于膜损伤较小，细胞活力更高。此外,除了表现出更高的有益微生物负荷外，它们还显示出更高的水分利用效率以及更多的养分积累。
结论：大豆植株接种有益微生物会减轻干旱胁迫的影响。从而使植物在胁迫条件下正常生长。因此，这项研究，推断，在干旱或水限制条件下种植大豆时，似乎有必要接种AM真菌和根瘤菌。
结果：在开花期和豆荚灌浆期施加的干旱胁迫表明，由B.liaoningense和A.leptitcha组成的双重接种改善了生理和生物特征，包括干旱条件下的养分吸收和产量。接种的植物显示每株植物的豆荚数量和豆荚重量分别增加了19％和34％，在干旱胁迫条件下，每株植物的种子数量和种子重量分别比未接种植物增加了17％和32％。Further,接种的植物表现出更高的叶绿素和渗透压物质含量，更高的解毒酶活性，在胁迫条件下，与未接种的植物相比，由于膜损伤较小，细胞活力更高。此外,除了表现出更高的有益微生物负荷外，它们还显示出更高的水分利用效率以及更多的养分积累。
结论：大豆植株接种有益微生物会减轻干旱胁迫的影响。从而使植物在胁迫条件下正常生长。因此，这项研究，推断，在干旱或水限制条件下种植大豆时，似乎有必要接种AM真菌和根瘤菌。
