水稻不同品种耐盐限度研究初报

了解水稻不同品种的耐盐限度，对于盐渍土区稻作生产的持续、稳定发展有着重要意义。试验表明，土壤全盐5．94g／kg时，盐粳68、花粳8、辽粳294和盐粳34的发芽率均不低于90％。花粳15分蘖期最高耐盐为14g／kg，盐粳68拔节孕穗期最高耐盐为17g/k，盐丰47—6成熟期最高耐盐为12g／kg。12个供试水稻品种，其中盐粳68、花粳8、辽粳9和92—71耐盐能力强；花粳15、抗盐100、盐丰47—6、辽粳294、盐粳34和盐粳31耐盐能力次之。     

辽宁省水稻品种苗期耐盐能力评价

对辽宁省29个水稻品种苗期150mmol/L NaCl水溶液处理条件下苗高、根长、根数、单株苗干重等指标进行分析,并对品种进行聚类.结果表明,盐丰47-8、辽盐282、辽粳371、辽盐12、桥201-2、辽盐241苗期耐盐能力较强,盐粳98、辽开79-3、沈农9418、铁粳4号、辽2096、沈农9741、盐粳34、铁粳...     

水稻不同品种耐盐限度研究

对盘锦地区水稻的几个主栽品种及有生产潜力的新品系,在种子发芽和不同生育时期的耐盐临界浓度及不同盐分抑制条件下的水稻生长状况进行研究。结果表明:水稻种子耐盐能力排序为辽盐糯>辽粳294>盐丰47>辽盐188>辽优2006>辽粳263>沈农9765>辽盐166>辽粳138>辽盐92;在不同生育时期供试水稻品种的耐盐能力排序为:发芽期辽盐糯>辽粳294>盐丰47>辽盐188>辽优2006>辽粳263>沈农9765>辽盐166>辽粳138>辽盐92;分蘖期盐粳68>H522>H757>辽盐166>辽盐188>K20;拔节-抽穗期辽盐166>辽盐188>盐粳68>K20>H522>H757;成熟期辽盐166>辽盐188>盐粳68>H757>H522>K20。     

水稻品种产量对比试验总结

为实现北宁地区水稻生产良种化,对当地目前栽培面积较大的辽优7等10个品种(系)进行常规品比试验。结果表明:辽优7和辽粳294-4产量最高,分别达9217.5kg/hm2和8527.5kg/hm2,极显著和显著地超过对照品种辽盐282。这两个品种可在北宁地区推广。     

水稻新品种盐粳456

盐粳水稻是辽宁省盐碱地所以盐丰47为母本,辽粳207为父本进行有性杂交,后代按系谱法进行选择,育成的高产、优质、多抗水稻新品种。一般产量650-700kg／667m^2。该品种于2010年通过辽宁省品种审定委员会审定。全生育期163d,株高103．9cm,穗粒数123．2粒／穗,结实率92．1％,干粒重26g,主茎16片叶,茎叶夹角小。     

水稻新品种盐粳68的评价与利用

盐粳68是辽宁省盐碱地利用研究所于2003年通过辽宁省品种审定委员会审定的高产优质水稻品种。该品种较辽宁省水稻主栽品种辽粳294株型好、产量高,生产中平均产量650kg/667m2,较对照增产10%以上。具有米质优、抗病性强等特点。在生产上极具推广潜力,在水稻育种上展示出较大利用价值。     

水稻品种产量对比试验总结

为实现北宁地区水稻生产良种化，对当地目前栽培面积较大的辽优7等10个品种(系)进行常规品比试验。结果表明：辽优7和辽粳294-4产量最高，分别达9217．5kg/hm^2和8527．5kg／hm2，极显著和显著地超过对照品种辽盐282。这两个品种可在北宁地区推广。     

优质水稻新品种试验总结

通过对东展1、辽星1号、千重浪等16个品种进行生产对比试验,结果表明:辽星1号在参试的品种中产量最高为648.4 kg/667 m2,较对照辽粳294增产26.8 kg/667 m2,可做为丰产型品种推广种植;东展3、兴粳2号-4、兴粳2号-7、兴粳2号-8,产量均在550～600 kg/667 m2,商品性状较好,可做为优质米品种推广种植。     

水稻分蘖成穗率的遗传变异研究

以水稻弯穗型辽盐2号等3个品种为母本,直立穗型辽粳326等4个品种为父本,研究了水稻分蘖成穗率的配合力和遗传力。结果表明,辽粳326一般配合力相对效应值最高为9．0,辽盐282次之为5．0,特殊配合力以辽盐282／辽粳294最高为58;分蘖成穗率的广义遗传力为825％,狭义遗传力为65．3％。     

水稻新品种盐粳68的评价与利用

盐粳68是辽宁省盐碱地利用研究所于2003年通过辽宁省品种审定委员会审定的高产优质水稻品种。该品种较辽宁省水稻主栽品种辽粳294株型好、产量高，生产中平均产量650kg／667m^2，较对照增产10％以上。具有米质优、抗病性强等特点。在生产上极具推广潜力，在水稻育种上展示出较大利用价值。     

水稻骨干亲本育种价值分析

在介绍粳稻丰锦、辽粳5号、盐粳32、盐粳68等来源及特点的基础上,以配合力为指标,分析了这4个品种的产量性状的遗传潜势,结合系谱分析,论证了骨干亲本的育种价值,并探讨了骨干亲本的利用方式。     

Antioxidant Defense Mechanisms of Salinity Tolerance in Rice Genotypes

In order to elucidate the role of antioxidant responses in salinity tolerance in rice genotypes under salt stress, experiments were conducted using four rice varieties, including salt-sensitive BRRI dhan 28 and three salt-tolerant varieties BRRI dhan 47, BINA dhan 8 and BINA dhan 10. Thirty-day-old rice seedlings were transplanted into pots. At the active tillering stage(35 d after transplanting), plants were exposed to different salinity levels(0, 20, 40 and 60 mmol/L NaCl). Salt stress caused a significant reduction in growth for all the rice genotypes. Growth reduction was higher in the salt-sensitive genotype than in the salt-tolerant ones, and BINA dhan 10 showed higher salt tolerance in all measured physiological parameters. The reduction in shoot and root biomass was found to be minimal in BINA dhan 10. Chlorophyll content significantly decreased under salt stress except for BINA dhan 10. Proline content significantly increased in salt-tolerant rice genotypes with increased salt concentration, and the highest proline content was obtained from BINA dhan 10 under salt stress. Catalase and ascorbate peroxidase activities significantly decreased in salt-sensitive genotype whereas significantly increased in salt-tolerant ones with increasing salt concentration. However, salt stress significantly decreased guaiacol peroxidase activity in all the rice genotypes irrespective of salt tolerance. K~+/Na~+ ratio also significantly decreased in shoots and roots of all the rice genotypes. The salt-tolerant genotype BINA dhan 10 maintained higher levels of chlorophyll and proline contents as well as catalase and ascorbate peroxidase activities under salt stress, thus, this might be the underlying mechanism for salt tolerance.     

Genetic diversity and association mapping for salinity tolerance in Bangladeshi rice landraces

Breeding for salinity tolerance using Bangladeshi rice landraces and understand genetic diversity has been limited by the complex and polygenic nature of salt tolerance in rice genotypes. A genetic diversity and association mapping analysis was conducted using 96 germplasm accessions with variable response to salt stress at the seedling stage. These included86 landraces and 10 indica varieties and lines including Nona Bokra, from southern Bangladesh. A total of 220 alleles were detected at 58 Simple Sequence Repeat(SSR) marker loci randomly distributed on all 12 rice chromosomes and 8 Sequence Tagged Site(STS) markers developed for genes SKC1, DST, and SalT. The average gene diversity was 0.5075 and polymorphism information content value was 0.4426, respectively. Cluster analysis revealed that 68 and 21 accessions were clustered into 2 distinct groups, possibly corresponding to indica and japonica groups, respectively and the remaining 7 landraces were classified as an admixed group. In addition to Wn11463, the STS marker for SKC1, RM22418 on Chr. 8 was significantly associated with salinity tolerance, at the location of a QTL detected in previous studies. Our findings of favorable alleles associated with salinity tolerance in Bangladeshi rice landraces, as well as the development of STS markers for salt tolerance genes, will be helpful in future efforts to breed salinity tolerance in rice.     

盐逆境对水稻产量、光合特性及品质的影响

【目的】江苏沿海滩涂种植水稻是促进盐土脱盐改良和开发利用滩涂的主要技术之一,研究盐逆境对水稻产量、光合特性和稻米品质的影响,可为发展滩涂种稻提供参考和理论依据。【方法】以耐盐性较好的通粳981、盐稻12、盐稻10号和南粳5055等4个粳稻品种为材料,设置非盐逆境(S₀, 电导率0.207 dS/m)和逆境(S₁,电导率1.112 dS/m)2个处理,分别测定产量及其构成因素、光合参数、稻米品质和淀粉黏滞特性。【结果】与非盐逆境相比,盐逆境下水稻产量显著下降,仅为非逆境的40.5%,单位面积穗数差异不显著,每穗粒数和千粒重显著减少;光合速率、胞间CO₂浓度显著下降,而气孔导度和蒸腾速率差异不显著;稻米加工品质显著下降,外观品质变化不大,直链淀粉含量显著下降,蛋白质含量显著增加;峰值黏度、热浆黏度、最终黏度、崩解值和回复值均未发生显著的变化,消减值和起始糊化温度显著增高。【结论】盐逆境对水稻产量、光合参数、稻米品质等均有不利的影响,可在盐逆境对产量、品质影响的关键时期孕穗期和灌浆结实期采取措施缓解盐逆境的危害。     

Selection of Rice Genotypes for Salinity Tolerance Through Morpho-Biochemical Assessment

The present study reported the morpho-biochemical evaluation of 15 selected rice genotypes for salt tolerance at the seedling stage. Growth parameters including shoot length, root length, plant biomass, plant turgid weight, plant dry weight along with relative water content were measured after exposure to saline solution （with electrical conductivity value of 12 dS/m）. Genotypes, showing significant differential responses towards salinity in the fields, were assessed through 14 salinity-linked morpho-biochemical attributes, measured at 14 d after exposure of seedling in saline nutrient solution. Relative water content, chlorophyll a/b, peroxidase activity and plant biomass were identified as potential indicators of salt tolerance. Principal component analysis and successive Hierarchical clustering using Euclidean distance revealed that Talmugur, Gheus, Ghunsi, Langalmura, Sabitapalui, and Sholerpona were promising genotypes for further breeding programmes in rice. The maximum Euclidean distance was plotted between Thavallakanan and Talmugur （7.49）, followed by Thavallakanan and Langalmura （6.82）, indicating these combinations may be exploited as parental lines in hybridization programmes to develop salinity tolerant variety.     

盐逆境对水稻产量、光合特性及品质的影响

【目的】江苏沿海滩涂种植水稻是促进盐土脱盐改良和开发利用滩涂的主要技术之一,研究盐逆境对水稻产量、光合特性和稻米品质的影响,可为发展滩涂种稻提供参考和理论依据。【方法】以耐盐性较好的通粳981、盐稻12、盐稻10号和南粳5055等4个粳稻品种为材料,设置非盐逆境(S0,电导率0.207 d S/m)和逆境(S1,电导率1.112 d S/m)2个处理,分别测定产量及其构成因素、光合参数、稻米品质和淀粉黏滞特性。【结果】与非盐逆境相比,盐逆境下水稻产量显著下降,仅为非逆境的40.5%,单位面积穗数差异不显著,每穗粒数和千粒重显著减少;光合速率、胞间CO2浓度显著下降,而气孔导度和蒸腾速率差异不显著;稻米加工品质显著下降,外观品质变化不大,直链淀粉含量显著下降,蛋白质含量显著增加;峰值黏度、热浆黏度、最终黏度、崩解值和回复值均未发生显著的变化,消减值和起始糊化温度显著增高。【结论】盐逆境对水稻产量、光合参数、稻米品质等均有不利的影响,可在盐逆境对产量、品质影响的关键时期孕穗期和灌浆结实期采取措施缓解盐逆境的危害。     

Inheritance and QTL Mapping of Salt Tolerance in Rice

An F2 population derived from the cross between Jiucaiqing (japonica) and IR36 (indica) was used to analyze the inheritance of salt tolerance in rice by genetic model of major-genes plus polygenes, and to map the corresponding QTLs by SSR molecular markers. Rice plants of P1, P2, F1 and F2 at 5- to 6- leaf stage were treated under 140 mmol/L NaCI for 10 days. Three indices representing the ability of salt tolerance of rice seedlings were measured, including salt tolerance rating (STR), Na^ /K^ ratio in roots and dry matter weight of shoots (DWS). STR, Na^ /K^ and DWS were all controlled by two major genes with modification by polygenes. Heritability of these traits from major genes was 17.8, 53.3 and 52.3%, respectively. The linkage map constructed by 62 SSR molecular markers covered a total length of about 1 142 cM. There were three QTLs detected for STR located on chromosome 1, 5 and 9, two QTLs for DWS on chromosomes 8 and 9, and two QTLs for Na^ /K^ on chromosomes 2 and 6, one on each chromosome respectively. Single QTL accounted for 6.7 to 19.3% of phenotypic variation. Identification method of salt tolerance in rice and breeding of rice varieties with salt tolerance based on molecular markers assisted selection had been discussed.