Screening of Rice Accessions for Tolerance to Drought and Salt Stress Using Morphological and Physiological Parameters

• 作者: Charles Opara Chukwudi Umego Edak Aniedi Uyoh Effiom Eyo Ita Valentine Otang Ntui
• 来源期刊: 美国植物学期刊(英文)
• 学科: 农学
• 关键词: Oryza sativa Salinity Tolerance Drought Tolerance Morpho-Physiological Parameters Stress Response Indices
• 年，卷（期）: mgzwxqkyw_2020,（12）
• 页码范围: 2080-2102
• 页数: 23页
• 分类号: S51

摘要

Drought and salinity are the most widespread soil problems, posing a big threat to food security in rice growing regions. The present study evaluated the performance of eleven rice genotypes using morphological and physiological parameters, under induced drought and salinity conditions. The seedlings were raised in 5 kg of homogenous soil in plastic bags in the </span><span style="font-family:Verdana;">greenhouse</span><span style="font-family:""><span style="font-family:Verdana;">. For the drought experiment, each bag was watered with 200 ml of water twice daily until plants reached the five-leaf stage when watering was suspended for 2 weeks for the drought stressed plants but not suspended for the control plants. The experiment was a 2 × 11 factorial and the set up was arranged using the completely randomized design with three replications. Data were taken on Plant height, Number of tillers, leaf length, Number of green leaves, Number of dead leaves, Leaf rolling score (LRS) and Rate of water loss. The salinity experiment was set up in a similar manner except that the plants were irrigated twice a day for 2 weeks with 200 ml of treatment solution containing either 0 mM NaCl or 75 mM and data were collected on plant height, number of tillers, shoot fresh weight, shoot dry weight, Na</span>^{<span style="font-family:Verdana;">+</span>}<span style="font-family:Verdana;"> and K</span>^{<span style="font-family:Verdana;">+</span>}<span style="font-family:Verdana;"> concentrations, relative water content and chlorophyll content. Data from both experiments were subjected to Analysis of variance test using the GenStat software 10</span>^{<span style="font-family:Verdana;">th</span>}<span style="font-family:Verdana;"> edition and the means separated using least significant difference test. Individual stress response index (ISRI) was calculated for each parameter and the means used in grouping the varieties. Of the genotypes evaluated, four (FARO 44, NERICA 2, NERICA 8 and NERICA 5) were identifi