花生苗期耐盐性评价及耐盐指标筛选

评价鉴选耐盐品种对于盐碱地花生生产具有重要意义。采用盆栽试验,设置不同盐胁迫浓度,对200个花生品种(系)萌发至幼苗期通过出苗速度、植株形态和生物量等指标进行耐盐性系统评价。结果表明,随盐胁迫浓度的增加,出苗时间延长,植株形态建成抑制加重,物质积累减少。鉴选花生品种耐盐性强弱的适宜盐胁迫浓度为0.30%—0.45%,超过此浓度不能出苗。地上部形态和生物量可作为耐盐评价的首选指标,主根长和出苗速度可作为辅助指标用以判断花生品种的综合耐盐能力。200个品种(系)在不同盐胁迫浓度下均可分成高度耐盐型、耐盐型、盐敏感型和高度盐敏感型4组。耐盐品种数量随盐胁迫强度加大而下降,盐敏感品种数量则上升。0.15%浓度下200个品种全部出苗,4个类型品种数分别占供试材料的29.0%、39.0%、27.5%和4.5%;0.30%浓度下185个品种出苗,4个类型品种数分别占供试材料的5.5%、34.5%、23.5%和29.0%;0.45%浓度下107个品种出苗,4个类型品种数分别占供试材料的5.5%、5.5%、20.0%和22.5%。14个品种在各盐浓度胁迫下均表现耐性,10个品种在各盐浓度胁迫下均表现敏感,为花生耐盐机理研究及生产应用提供了不同类型材料。

Evaluation and selection indices of salinity tolerance in peanut seedling

Soil salinity has become the most important problems for agricultural production. The damaging effect of salt accumulation in agricultural soils has become an important environmental concern. Peanut (Arachis hypogaea L.) is an economically important oil seed crop in the world. The supply for the world peanut production could not meet the increasing demand for peanut oil and food in recent years. To date, due to the increase in the area of land planted with alimentary crops, peanut planting was decreased. Therefore, it is important to evaluate and select salinity tolerant varieties for peanut production in saline land. In the present study, the degree of salinity tolerance of two hundred peanut materials including germplasm resources and varieties was investigated from emergence to seedling stage. The seeds of peanut were pot-planted with salinity levels of 0, 0.15%, 0.30% and 0.45% NaCl in the soil.. The degree of salinity tolerance was systematically evaluate to select high salinity tolerant varieties according to the 10 indices including relative emergence rate, relative plant height, relative stem height, relative taproot length, relative shoot fresh mass, relative root fresh mass, relative shoot dry mass, relative root dry mass and relative plant dry mass. The results showed that the emergence time was prolonged in the treatments with high soil salinity; and plant morphology establishment and biomass accumulation were inhibited seriously. Statistic analysis for the 10 indices showed large variations among the 200 varieties, but each index showed a normal distribution trend. The optimal salinity level for evaluating salinity tolerance in peanut was from 0.30% to 0.45% NaCl. Peanut seeds could not emerge when the soil salinity level exceeded 0.45% NaCl. Principal component analysis was used to extract the effective information for salinity tolerance evaluation because of the significance of relation among the ten indices. The shoot morphology and biomass could be used as the first candidates for evaluating salinity tolerance in peanut varieties/lines, and the taproot length and emergence rate could be used as the second candidates to comprehensively evaluate salinity tolerance. According to the total score, the 200 varieties were divided into 4 groups, i.e., high salinity tolerance, salinity tolerance, salinity sensitive and high salinity sensitive, by cluster analysis at soil salinity level of 0.15%, 0.30% and 0.45% NaCl, respectively. The number of salinity tolerant varieties was decreased with the increasing salinity level, while the number of salinity sensitive varieties was increased. Two hundred varieties/lines could emerge under soil salinity level of 0.15% NaCl and accounted for 29.0%, 39.0%, 27.5% and 4.5% in high salinity tolerance group, salinity tolerance group, salinity sensitive group and high salinity sensitive group, respectively. One hundred and eighty-five varieties/lines could emerge under soil salinity level of 0.30% NaCl and accounted for 5.5%, 34.5%, 23.5% and 29.0%, respectively, in each group. One hundred and seven varieties/lines could emerge under soil salinity level of 0.45% NaCl and accounted for 5.5%, 5.5%, 20.0% and 22.5%, respectively, in each group. Especially, fourteen varieties/lines (Luhua 11, HLY2, Huayu 32, 561, Yueyou 26, Yueyou 85, Xianghua 11, Xiangxiang, XE019, 555, Fuhua 11, Yueyou 186, 543 and HZ13) showed tolerance and 10 varieties/lines (Yuhua15, Z8, Z6, Huayu 24, Weihua 6, 1018, Silihong, D1035, HR4 and Yueyou 101) showed sensitive under soil salinity levels of 0.15%, 0.30% and 0.45% NaCl, which could be provided for further research on salinity tolerant mechanism and production application in peanut plant.