为了选择适宜松嫩地区轻度盐碱化草地种植的牧草，解决饲草蛋白质含量低的问题，发展耐盐碱的优质豆科牧草是关键。种子发芽和幼苗生长是植物生活史最关键的阶段，决定着植株的后续生长。本实验研究了盐对黄花苜蓿种子发芽和幼苗生长的影响，与紫花苜蓿ＣＷ ４００ 和紫花苜蓿公农２号对比，在０，２０，４０，６０，８０，１００，１２０，１４０，１６０，１８０，２００ｍｍｏｌ／Ｌ 浓度ＮａＣｌ胁迫条件下，研究了３种材料的种子发芽率、发芽指数（Ｇｉ），胚根、胚轴生长状况及脯氨酸含量。结果表明，随着盐浓度的升高３种苜蓿的发芽率、发芽指数（Ｇｉ）都受到不同程度的抑制，盐浓度越高，抑制作用越明显。与紫花苜蓿ＣＷ ４００ 及公农２号相比，黄花苜蓿在发芽百分数和发芽指数上显著降低，但是胚根生长不受盐浓度的影响，各处理与对照间没有显著差异。复萌实验结果显示３种苜蓿种子在盐溶液中能够保持活力。紫花苜蓿ＣＷ ４００ ，黄花苜蓿均在６０ｍｍｏｌ／Ｌ ＮａＣｌ中达到最大总发芽率100％，但只有黄花苜蓿在所有盐浓度下总发芽率全部达到９０％以上，各盐处理间复萌率无显著差异，复萌率最高。脯氨酸作为渗透调节剂在幼苗中能够迅速积累，黄花苜蓿、紫花苜蓿ＣＷ ４００ 和紫花苜蓿公农２ 号在１００ ｍｍｏｌ／Ｌ ＮａＣｌ中的脯氨酸量分别是对照的３．１，２．３和１．４倍。黄花苜蓿耐盐性较紫花苜蓿ＣＷ ４００ 和紫花苜蓿公农２号强，更适合在松嫩草地上种植。

Salinity is one of the major environmental stresses impeding crop growth, which can lead to a series of morphological, physiological, biochemical and molecular changes that severely reduces agricultural yields and productivity. The ability to tolerate salinity stresses differs widely among species of plants as well as within different varieties in the same species. As an important cash crop, productivity of soybean can be significantly hampered by soil salt stresses and high salinity can sharply decline growth and give bad impacts on variable agronomy traits, seed quality and quantity, and finally reduce its commercial yield. Although most soybean varieties are sensitive to salt stresses, soybean germplasms display a spectrum of salt tolerance capability from high to low. Moreover, the degree of salt tolerance of soybean varieties varies among different developmental stages. To achieve a better understanding of salt tolerant mechanisms of soybean varieties, and determine the most reliable indicators for distinguishing high salt-tolerance varieties, seeds of 4 soybean varieties (respectively, 21066-2, 22021-1, 22293-1 and 22451-1 provided by Harbin Agricultural Academy of Science) were sowed in soil containers(45 cm in length,32 cm in width, 13.5 cm in height) for simulating natural growth conditions, and their salt tolerance capability in emergence and seedling stages under 150 mmol/L NaCl treatments were evaluated in this paper through measuring variable morphological and physiological parameters including plant height, hypocotyls length, lateral root numbers, fresh and dry weight of shoots and roots, contents of malondialdehyde (MDA) and free proline (Pro), activity of superoxide dismutase (SOD) in emergence and seedling stages. And then the seedlings were transplanted into field for recording seed yield at their natural maturity. Our results clearly showed that NaCl treatments could strongly decrease the plant height, fresh and dry weight of shoots and roots of the 4 varieties both in their emergence stage and seedling stage, while lateral root numbers and hypocotyls length decreased in the emergence stage but increased in the seedling stage. Under the unstressed control condition, MDA content and SOD activity in the salt-tolerant 22021-1 variety were significantly higher than those in the salt-sensitive 22293-1 variety both in the emergence stage and seedling stage ( P P P P P >0.05), while these salt stresses slightly increased the SOD activity in the two stages but cannot be up to statistical significance ( P >0.05). The final commercial yield was affected by the short-term salt stress treatments, but differed in different soybean varieties. Generally, the salinity tolerance or sensitivity of soybean varieties were well related to their antioxidant response, and high salt stress tolerability in the 22021-1 variety was associated with the ability of maintaining higher SOD activity for lowering the possible lipid peroxidation. Our finding indicates that leaf MDA level and SOD activity could be used as two physiological indices for assessing the salt tolerability of variable soybean varieties.

比较了4个大豆品种出苗期和苗期的耐盐性,测定150 mmol/L NaCl胁迫下的株高、下胚轴长、侧根数、地上干/鲜重、根干/鲜重、MDA含量、SOD活性、游离Pro含量,并将幼苗移栽到田间生长至成熟。结果表明:出苗期和苗期盐胁迫下4个品种的株高都显著降低、地上干/鲜重和根干/鲜重降低;出苗期胁迫侧根数减少,下胚轴长降低;而苗期胁迫侧根数增加,下胚轴长升高。未胁迫条件下,出苗期和苗期耐盐性强的品种22021-1的MDA含量和SOD活性高于耐盐性弱的品种22293-1。胁迫后,22021-1的MDA含量降低、SOD活性升高,其MDA含量分别比对照低51.03%和21.45%,SOD活性比对照高5.85%和45.77%;22293-1的MDA含量出苗期比对照高58.97%,苗期基本无变化,SOD活性出苗期和苗期升高都不显著。MDA和SOD可以作为大豆耐盐性筛选指标。早期的短时胁迫对不同耐盐性大豆品种的经济产量影响不同。

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.

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。

A neutral salt(NaCl) solution and various mixed salt(NaCl,Na 2 SO 4 ,NaHCO 3 ,Na 2 CO 3 in different proportions) solutions with different pH values were used to imbibe Albizia julibrissin seeds to simulate alkali-salt stresses.Results indicated that there were significantly negative correlations between germination rate,germination energy,germination index and vigor index of the stressed seeds and the salt concentrations.With the increasing of salt concentrations,the activities of SOD,POD and CAT displyed a mold of increasing at beginning and then decreasing.The mixed salts exerted stronger stress on young seedlings than the neutral salt.It was found that there was an obvious synergism between salt stress and pH stress and the mixed salts were more harmful than neutral salt to the seed germination and the seedlings of Albizia julibrissin .

用不同浓度的NaCl、Na2CO3和Na2SO4盐溶液处理绿豆的种子,对绿豆种子的发芽率、发芽速度、发芽指数的影响进行测定分析.结果表明:绿豆在种子萌发出芽阶段表现出较强的耐盐性,在100～200 mmol/L的NaCl和Na2SO4胁迫下对绿豆种子发芽率影响不明显,但显著抑制幼苗生长.在低浓度Na2CO3胁迫下绿豆种子萌发、幼苗生长均受到明显抑制,说明绿豆不耐碱性盐Na2CO3.