Nitric oxide (NO) has a diverse role in plant metabolism under stressful cues. This study was carried out to evaluate the effectivity of exogenously applied (pre-sowing and foliar) NO to minimize the adversaries of salinity stress on broccoli plants. Experimental design was completely randomized along with four replicates. Two levels of nitric oxide, control (0 mM) and 0.02 mM were applied on broccoli plants subjected to salt stress (120 mM) and non-stress conditions. Data showed that salinity stress significantly reduced fresh or/and dry weights of roots and shoots, root length, chlorophyll (a and b) contents, while it significantly increased total phenolics, hydrogen peroxide (H₂O₂), malondialdehyde (MDA), glycine betaine, proline, ascorbic acid, activities of catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD) enzymes. The external application of NO via both pre-treatment as well as foliar application improved chlorophyll a, total phenolics, glycine betaine, and activities of SOD, CAT and POD enzymes while it was more helpful in lowering levels of H₂O₂ and MDA, however, it remained ineffective for shoot length. Overall, both modes of NO were effective in improving plant growth, chlorophyll a, proline and glycine betaine contents under stress conditions. The results indicated that external use of NO is beneficial for minimizing the salinity adversaries in broccoli plants.

一氧化氮（NO）在胁迫提示下在植物代谢中具有多种作用。进行这项研究以评估外源施用（播种前和叶面施用）NO的有效性，以最大程度降低西兰花植物上盐分胁迫的危害。实验设计完全随机化，一式四份。将两种水平的一氧化氮，对照（0 mM）和0.02 mM施用到经受盐胁迫（120 mM）和非胁迫条件的西兰花植物上。数据显示盐分胁迫显着降低了根和茎的鲜重和/或干重，根长，叶绿素（a和b）含量，同时显着增加了总酚，过氧化氢（H ₂ O _2）），丙二醛（MDA），甘氨酸甜菜碱，脯氨酸，抗坏血酸，过氧化氢酶（CAT），超氧化物歧化酶（SOD）和过氧化物酶（POD）酶的活性。通过预处理和叶面施用的NO外部施用均改善了叶绿素a，总酚，甘氨酸甜菜碱以及SOD，CAT和POD酶的活性，同时更有助于降低H ₂ O ₂和MDA含量，但是，它对芽的长度仍然无效。总体而言，在胁迫条件下，两种模式的NO都能有效改善植物生长，叶绿素a，脯氨酸和甘氨酸甜菜碱的含量。结果表明，外部使用NO有利于将西兰花植物中的盐分危害最小化。