Growth Properties and Ion Distribution in Different Tissues of Bread Wheat Genotypes (Triticum aestivum L.) Differing in Salt Tolerance

Four bread wheat genotypes differing in salt tolerance were selected to evaluate ion distribution and growth responses with increasing salinity. Salinity was applied when the leaf 4 was fully expanded. Sodium (Na⁺), potassium (K⁺) concentrations and K⁺/Na⁺ ratio in different tissues including root, leaf‐3 blade, flag leaf sheath and flag leaf blade at three salinity levels (0, 100 and 200 mm NaCl), and also the effects of salinity on growth rate, shoot biomass and grain yield were evaluated. Salt‐tolerant genotypes (Karchia‐65 and Roshan) showed higher growth rate, grain yield and shoot biomass than salt‐sensitive ones (Qods and Shiraz). Growth rate was reduced severely in the first period (1–10 days) after salt commencements. It seems after 20 days, the major effect of salinity on shoot biomass and grain yield was due to the osmotic effect of salt, not due to Na⁺‐specific effects within the plant. Grain yield loss in salt‐tolerant genotypes was due to the decline in grain size, but the grain yield loss in salt‐sensitive ones was due to decline in grain number. Salt‐tolerant genotypes sequestered higher amounts of Na⁺ concentration in root and flag leaf sheath and maintained lower Na⁺ concentration with higher K⁺/Na⁺ ratios in flag leaf blade. This ion partitioning may be contributing to the improved salt tolerance of genotypes.     

Development of salt tolerant IR64 near isogenic lines through marker-assisted breeding

Salt stress causes considerable damage to rice with a consequent reduction in grain yield, however, conventional breeding for this stress is time-consuming and costly. Recently, marker-assisted breeding has shown enormous potential to accelerate breeding of stress tolerant varieties because of its precision, time saving, and cost effectiveness. The present study was carried out to transfer Saltol, a major QTL on chromosome 1 associated with salinity tolerance, from FL478, a tolerant genotype, into IR64, a popular lowland variety through marker-assisted backcrossing (MABC). This technique considerably enhanced the recovery rate of the recurrent parent genome within three backcross generations, which could have saved several backcrosses compared with conventional schemes to achieve the same results. By using this technique, up to 99.7% of the recurrent parent genome was recovered at BC₃F₂ generation, saving at least three backcrosses compared with conventional breeding schemes. Salinity tolerance of IR64-Saltol lines was evaluated using saline culture solution adjusted to electrical conductivity of 12 dS m^-1 using NaCl. Based on selected physiological and growth parameters, the new Saltol introgression lines showed a significantly higher tolerance of salinity than their recurrent parent IR64. The results of this study confirm the benefits of using molecular markers in plant breeding to enhance tolerance of abiotic stresses.     

Variation in Salinity Tolerance in Sunflower (Helianthus annum L.)

Forty-five accessions of sunflower collected from different countries were screened for salinity tolerance after 2 weeks growth in sand culture salinized with 150 meq l^?1 of NaCl₂+ CaCl₂ (1:1 ratio equivalent wt. basis) in half strength Hoagland's nutrient solution. The results for plant biomass of 45 accessions show that there was considerable variation in salinity tolerance. In a further greenhouse experiment, the salinity tolerance of three tolerant (HO-1, Predovik, Euroflor) and two sensitive (SMH-24, 9UO-985) lines (selected on the basis of their performance in the seedling experiment) was assessed at the adult stage to evaluate the consistency of salinity tolerance at different growth stages. All three salt tolerant accessions produced significantly greater plant biomass, seed yield and seed oil content than the salt sensitive accessions. The tolerant accessions accumulated less Cl^? and more K⁺ in the leaves under saline conditions compared with the salt sensitive accessions. The salt tolerant accessions also maintained relatively high leaf K:Na ratio and K⁺ versus Na⁺ selectivity. Although statistically nonsignificant, all three tolerant accessions had greater soluble carbohydrates, soluble proteins, total free amino acids and proline in the leaves than the sensitive accessions. A field trial conducted in a salt-affected field confirmed the greenhouse results of the selected accessions. This study shows that salinity tolerance of sunflower does not vary with stage of plant cycle, so selection for increased salt tolerance can be carried out at the initial growth stage. Secondly, it is found that there is great variation of salt tolerance in sunflower. Low uptake of Cl^?, high uptake of K⁺, and maintenance of high K:Na ratios and K⁺ versus Na⁺ selectivity in the leaves and possibly the accumulation of organic osmotica such as soluble carbohydrates, soluble proteins, proline and free amino acids seem to be the important components of salt tolerance in sunflower.     

Identification of pearl millet [Pennisetum glaucum (L.) R. Br.] lines tolerant to soil salinity

Crop tolerance to salinity is of high importance due to the extent and the constant increase in salt-affected areas in arid and semi-arid regions. Pearl millet (Pennistum glaucum), generally considered as fairly tolerant to salinity, could be an alternative crop option for salt affected areas. To explore the genotypic variability of vegetative-stage salinity tolerance, 100 pearl millet lines from ICRISAT breeding programs were first screened in a pot culture containing Alfisol with 250 mM NaCl solution as basal application. Subsequently, 31 lines including many parents of commercial hybrids, selected from the first trial were re-tested for confirmation of the initial salinity responses. Substantial variation for salinity tolerance was found on the basis of shoot biomass ratio (shoot biomass under salinity/ non-saline control) and 22 lines with a wide range of tolerance varying from highly tolerant to sensitive entries were identified. The performance of the genotypes was largely consistent across experiments. In a separate seed germination and seedling growth study, the seed germination was found to be adversely affected (more than 70% decrease) in more than half of the genotypes with 250 mM concentration of NaCl. The root growth ratio (root growth under salinity/control) as well as shoot growth ratio was measured at 6 DAS and this did not reflect the whole plant performance at 39 DAS. In general, the whole plant salinity tolerance was associated with reduced shoot N content, increased K⁺ and Na⁺ contents. The K⁺/Na⁺ and Ca⁺⁺/Na⁺ ratios were also positively related to the tolerance but not as closely as the Na⁺ content. Therefore, it is concluded that a large scope exists for improving salt tolerance in pearl millet and that shoot Na⁺ concentration could be considered as a potential non-destructive selection criterion for vegetative-stage screening. The usefulness of this criterion for salinity response with respect to grain and stover yield remains to be investigated.     

Screening sorghum genotypes for salinity tolerant biomass production

Genetic improvement of salt tolerance is of high importance due to the extent and the constant increase in salt affected areas. Sorghum [Sorghum bicolor (L.) Moench] has been considered relatively more salt tolerant than maize and has the potential as a grain and fodder crop for salt affected areas. One hundred sorghum genotypes were screened for salinity tolerance in pots containing Alfisol and initially irrigated with a 250-mM NaCl solution in a randomized block design with three replications. Subsequently 46 selected genotypes were assessed in a second trial to confirm their responses to salinity. Substantial variation in shoot biomass ratio was identified among the genotypes. The performance of genotypes was consistent across experiments. Seven salinity tolerant and ten salinity sensitive genotypes are reported. Relative shoot lengths of seedlings were genetically correlated to the shoot biomass ratios at all stages of sampling though the relationships were not close enough to use the trait as a selection criterion. In general, the whole-plant tolerance to salinity resulted in reduced shoot Na⁺ concentration. The K⁺/Na⁺ and Ca²⁺/Na⁺ ratios were also positively related to tolerance but with a lesser r ². Therefore, it is concluded that genotypic diversity exists for salt tolerance biomass production and that Na⁺ exclusion from the shoot may be a major mechanism involved in that tolerance.     

Estimation of genetic components of variation for salt tolerance in chickpea using the generation mean analysis

Chickpea (Cicer arietinum L.) is known to be salt-sensitive and in many regions of the world its yields are restricted by salinity. Recent identification of large variation in chickpea yield under salinity, if genetically controlled, offers an opportunity to develop cultivars with improved salt tolerance. Two chickpea land races, ICC 6263 (salt sensitive) and ICC 1431 (salt tolerant), were inter-crossed to study gene action involved in different agronomic traits under saline and control conditions. The generation mean analysis in six populations, viz. P₁, P₂, F₁, F₂, BC₁P₁ and BC₁P₂, revealed significant gene interactions for days to flowering, days to maturity, and stem Na and K concentrations in control and saline treatments, as well as for 100-seed weight under salinity. Seed yield, pods per plant, seeds per plant, and stem Cl concentration were controlled by additive effects under saline conditions. Broad-sense heritability values (>0.5) for most traits were generally higher in saline than in control conditions, whereas the narrow-sense heritability values for yield traits, and stem Na and K concentrations, were lower in saline than control conditions. The influence of the sensitive parent was higher on the expression of different traits; the additive and dominant genes acted in opposite directions which led to lower heritability estimates in early generations. These results indicate that selection for yield under salinity would be more effective in later filial generations after gene fixation.     

Inheritance of cellular thermotolerance in bread wheat

Leaf membrane stability (LMS) and the tetrazolium triphenyl chloride (TTC) test, heat susceptibility index (HSI), heat response index (HRI) and grain yield were used to evaluate 20 diverse wheat genotypes under normal and heat stress conditions for 2 years. The varieties ‘Seri’ and ‘Raj 3765’ had a desirable combination of cellular thermotolerance (TTC and LMS), heat tolerance (HRI) and high grain yield potential under heat stress, while ‘WH 730’ and ‘WH 533’ were better in cellular thermotolerance and heat tolerance. The varieties ‘PBW 373’ and ‘Kauz’ also performed better under heat stress in terms of grain yield and HSI/HRI. The varieties ‘Kanchan’, ‘PBW 373’, ‘NIAW 34’ and ‘GW 173’ were avoiders/escapers, ‘Seri’ and ‘HUW 234’ were tolerant to heat stress, while ‘WH 730’, ‘WH 533’, ‘Nesser’, ‘Raj 3765’ and ‘Kauz’ showed a combination of both. Correlation coefficients revealed that HRI was the most important trait, followed by TTC because the genotype having high HRI also had high grain yield and was better in mitochondrial viability and membrane stability under heat stress. Significance of GCA and SCA variances indicated the presence of both additive and dominant types of gene action. The use of the parents with high GCA effects, namely, ‘Raj 3765’ and ‘WH 730’ in a crossing programme for thermotolerance may provide desirable segregants through selection.     

New quantitative trait loci for enhancing adaptation to salinity in rice from Hasawi,a Saudi landrace into three African cultivars at the reproductive stage

Salinity is a major constraint affecting rice productivity in rainfed and irrigated agro-ecosystems. Understanding salinity effects on rice production at the reproductive stage could improve adaptation for this trait. Identifying quantitative trait loci (QTLs) controlling adaptation to salinity may also accelerate breeding rice germplasm for environments prone to this stress. We used the salt tolerant landrace ‘Hasawi’ as a donor parent to generate three F₂ offspring (consisting each of 500 individuals) with three African cultivars (‘NERICA-L-19’, ‘Sahel 108’ and ‘BG90-2’) used as recipient parents (RP). The F₂s and F_2:3s were evaluated for grain yield and other traits in saline fields. Salinity caused reduction in all measured traits across the F₂-derived offspring, e.g. grain yield reduced between 65 and 73 %, but some offspring had twice the RP’s grain yield. QTL analysis revealed 75 QTLs for different traits in all 3 genetic backgrounds (GBs): 24 of them were common among all the 3 GBs while 31 were noted in 2 GBs, and 17 in one GB. ‘Hasawi’ contributed on average 49 % alleles to these QTLs. Two yield and yield related QTLs (qGY11 and qTN11) common in all 3 GBs were mapped on the same chromosomal segment suggesting these QTLs might be stable across different GBs. Four other QTLs were strongly associated with salinity tolerance with peak marker RM419, representing a potential candidate for MAS due to high LOD score and relatively large effect QTLs.     

Reproductive stage tolerance to salinity and alkalinity stresses in rice genotypes

Salinity and alkalinity (sodicity) seriously threaten rice production in south Asia. Improving screening methodologies for identifying sources of tolerance is crucial for breeding salt tolerant rices. Rice genotypes of varying tolerance (tolerant, semi‐tolerant and sensitive) were screened in saline soil of electrical conductivity, ECe 4 and 8 dS/m and alkali soil of pH 9.5 and 9.8 in lysimeters. Vegetative growth events were less affected by both the stresses in comparison to reproductive stage. Grain yield was reduced by 26.7%, 45.7% and 50.3% at ECe 8 dS/m in three tolerance groups respectively. At pH 9.8 the reduction was 25.1%, 37.2% and 67.6% in the three groups respectively. Higher floret fertility contributed to higher seed set and grain yields in tolerant genotypes whereas higher spikelet sterility led to poor seed set and lower grain yields in sensitive genotypes. The 1000 grains weight was also significantly reduced at ECe 4 or pH 9.8. Screening at reproductive stage for morphological traits like floret fertility is thus more useful to identify rice genotypes tolerant to both salinity and alkalinity stress. Genotypic (G) and environmental (E) effects and GE interactions were highly significant for the growth attributes and grain yield. Based on analysis of variance, genotypes tolerant to salinity and alkalinity as well to both the stresses were identified.     

Redox halopriming: A Promising Strategy for Inducing Salt Tolerance in Bread Wheat

New strategies to enhance growth and productivity of food crops in saline soils represent important research priorities. This study has investigated the role of certain priming techniques to induce salt tolerance of bread wheat. Wheat grains were soaked in 0.2 mm sodium nitroprusside as nitric oxide donor (redox priming), diluted sea water (halopriming) and the combination of both (redox halopriming). Grains were also soaked in distilled water (hydropriming); in addition, untreated grains were taken as control. Our results indicated that priming treatments significantly improved all growth traits and increased leaf pigments concentration as compared to the control. Priming treatments markedly enhanced membrane stability index, proline, total soluble sugars and K⁺ concentration with simultaneous decrease in the concentration of Na⁺ and malondialdehyde (MDA). Furthermore, yield and yield‐related traits such as plant height, spike length, total number of tillers, 1000‐grain weight, straw and grain yield considerably affected by priming treatments. Moreover, the grain yield of both genotypes was positively affected by redox halopriming treatment. However, the extent of enhancement was more prominent in Gemmiza‐9 (salt sensitive) than that in Sakha‐93 (salt‐tolerant). Overall, this study clearly indicated that redox halopriming treatment is a promising and handy technique to induce salinity tolerance of wheat genotypes.     

Mapping QTLs for salt tolerance in an introgression line population between Japonica cultivars in rice

QTL analysis of physiological traits related to salt tolerance was carried out using 117 BC₃F₅ lines derived from a cross between “Ilpumbyeo” as a recurrent parent and “Moroberekan” as a donor parent. The 117 introgression lines with the parents were evaluated for five traits; dry weight, fresh weight, leaf area, seedling height, and survival rate under control and salinity conditions (55 mM) at the seedling stage. To identify QTLs related to salt tolerance, 125 SSR markers showing polymorphisms between the parents were genotyped for the 117 BC₃F₅ lines. A total of eight QTLs were detected on chromosomes 1, 6, and 7. These include two QTLs on chromosomes 6 and 7 for reduction rate of dry weight (R² = 10.2∼13.6%), three QTLs on chromosomes 1, 6, and 7 for reduction rate of fresh weight (R² = 10.9∼13.9 %), two QTLs on chromosomes 1 and 7 for reduction rate of leaf area (R² = 12.1%), and one QTL on chromosome 7 for reduction rate of seedling height (R² = 10.5%). The Moroberekan alleles contributed the positive effect at these eight QTL loci. Although the parents, Ilpumbyeo and Moroberekan, were not salt tolerant as the salt tolerant check variety, Pokkali, some lines displayed a similar level of tolerance as Pokkali. The effect of the QTL on chromosome 7 was further confirmed by evaluating four lines containing the target QTL for fresh and dry weight, turgid weight, and relative water content (RWC). Significant differences between each line and Ilpumbyeo were detected for dry and fresh weight, and RWC values, and these results seem to indicate the beneficial effect of the Moroberekam alleles for salt tolerance. A set of introgression lines are being developed containing only few chromosomal segments from Moroberekan in the Ilpumbyeo background. These would be useful in developing salt tolerant lines in the breeding program.     

Inheritance of Aluminum Tolerance and its Effects on Grain Yield and Grain Quality in Oats (Avena Sativa L.)

Summary Aluminum toxicity due to the cation Al⁺³ is a major factor limiting yields in acid soils. Wide genetic variability to aluminum tolerance is found in oat genotypes. The objectives of this study were to determine the number of genes controlling aluminum tolerance in oats and to verify if any detrimental effects were present of the aluminum tolerance genes on grain yield and grain quality in Al⁺³free soils. Aluminum tolerance was estimated as the average regrowth of the main root after exposure to toxic levels of Al⁺³ in a hydroponic solution under controlled conditions. The number of genes controlling that trait was estimated from the distribution of the average root regrowth frequencies in a population of 333 recombinant inbred lines (RIL's) in generations F_5:6 and F_5:7. The effects on grain yield and grain quality were assessed in a subpopulation of 162 RIL's chosen based on their aluminum tolerance response. Aluminum tolerance in the evaluated population was controlled by one dominant major gene with the tolerant genotypes carying Al _a Al _a and the sensitive ones al _a al _a alleles. No detrimental effects of the Al _a allele on grain yield or grain quality were detected.Part of the Master of Science dissertation of the first author     

Nutrient culture media with agar is effective for early and rapid screening of iron toxicity tolerance in rice

The breeding for iron toxicity tolerant rice needs an effective, efficient, and reliable screening method. The study was aimed to evaluate the best method for screening iron tolerant genotypes at the seedling stage in the greenhouse. Two rice genotypes, Mahsuri (tolerant) and IR64 (sensitive) were grown in three modified media solutions namely, Yoshida-conventional solution (YCS), Yoshida with etylenediamintetraacetic acid (1:2) (YES), and Yoshida with 0.2% agar (YAS). Three levels of iron were tested to observe the severity of their leaf bronzing score (LBS). The optimized solution in the greenhouse was then evaluated using 24 rice genotypes. Using the same genotypes interrelationship, the LBS in the greenhouse with grain yield and its attributes was validated under acute and moderate Fe toxicity in the field. The results showed that the optimized media culture was YAS with 400 mg L^-1 of FeSO₄. This media had more stable pH and redox potential, it could maintain sufficient Fe²⁺ supply over 10 days, and it could discriminate of LBS between tolerant and sensitive genotypes. Evaluation using the optimized media solution showed that there was a significant variation among genotypes in shoot dry weight and a significant correlation of relative reduction of shoot dry weight with LBS. The LBS in the greenhouse was correlated with LBS in acute iron stress in the field (r=0.673**) and the grain yield (r= -0.618**). This study has proven that YAS culture media can be used as early identification of iron toxicity tolerant genotypes for supporting breeding programs.     

Genetic analysis of salt tolerance at seedling and reproductive stages in rice (Oryza sativa)

Salinity is a major abiotic stress that limits rice production across rice areas as high‐yielding modern rice varieties are generally sensitive to salt stress. The study was conducted to deduce heritability and combining ability estimates of rice for various morphological and physiological traits using a 7 × 7 full‐diallel‐cross analysis at seedling and reproductive stages. The salinity stress treatment was 12 dS m^?1 at the seedling stage and 8 dS m^?1 at the reproductive stage. Diallel analysis revealed high for salinity tolerance scores and shoot height, moderate for shoot dry weight and root dry weight and low for Na⁺ and K⁺ concentrations and K⁺/Na⁺ ratio. The low‐to‐moderate narrow‐sense heritability for number of panicles, number of fertile spikelets, grain weight, spikelet fertility and K⁺/Na⁺ ratio suggests a large breeding population and delayed selection for tolerance until later generations. Significant maternal effects indicate that selection of the female parent is very important for desired trait development. The results of this study confirmed that salinity tolerance at the seedling and reproductive stages is regulated by a different set of genes that could be pyramided using different donors to enhance the level of tolerance.     

Marker‐assisted backcross breeding for improvement of drought tolerance in bread wheat (Triticum aestivum L. em Thell)

Drought stress is presently a major productivity limiting factor in wheat. This study developed five wheat lines with inbuilt tolerance to drought stress using marker‐assisted backcross breeding (MABB) approach employing three linked quantitative trait loci (QTLs) in an initial population of 516 BC₁F₁ plants. The high‐yielding wheat cultivar ‘HD2733’ grown over last few years extensively in the eastern plains of India is largely sensitive to drought and is used as the recurrent parent. ‘HI1500’ released for water‐limiting conditions and carrying drought‐tolerant QTLs was used as donor parent. MABB lines were advanced using foreground and background selection, coupled with stringent phenotyping. We identified 29 lines that were homozygous for targeted QTLs in different combinations with background recovery range of 89.2%–95.4%. Further evaluation of selected lines for physiological traits and distinctness, uniformity and stability (DUS) characters under rainfed condition identified five potential varieties for national varietal evaluation programme in the zone. The report is first of its kind in implementing known QTLs for the development of drought‐tolerant wheat lines through MABB approach.     

The mechanism of genetic control for low soil nitrogen (N) tolerance in common beans (Phaseolus vulgaris L.)

The study was conducted to determine the mode of inheritance and the genetic mechanisms associated with bean nitrogen use efficiency under low soil nitrogen. Eight widely grown and well adapted low soil N tolerant lines (CAL143, CIM9314-36, and AFR708) and non-tolerant varieties (E5, E8, GLP-2, CAL96, and SCAM80-CM/15) were crossed in a half diallel mating design. The parents and their F₁ generations were evaluated under low soil N and moderate soil N conditions. Significant genetic differences were observed for basal root length, root dry weight, nodule numbers, leaf area and grain yield for both N conditions. Inheritance of the traits associated with better performance under low soil N was found to be under both additive fixable and non-fixable genetic effects. Genotypes that had well-developed basal root systems performed better than those with less developed basal roots. F₁ hybrids from crosses between low N tolerant and non-tolerant parents performed better under nitrogen stressed conditions compared with those between susceptible parents. Hybrids involving CAL143 as one of the parents showed high levels of tolerance to low soil nitrogen conditions. Among parents, CAL143 showed the best performance for basal root length, root dry weight, nodule numbers, leaf area, and grain yield. This parent had highly significant GCA effects for the traits under both N conditions, except basal root length which was significant at Kabete and non-significant leaf area at Thika. The results show that CAL143 would be a good parent to use in a low soil N bean breeding program.     

Major gene control of tolerance of bread wheat (Triticum aestivum L.) to high concentrations of soil boron

Summary The genetic control of tolerance of wheat to high concentrations of soil boron was studied for five genotypes. Each genotype represented one of five categories of response to high levels of boron, ranging from very sensitive to tolerant. Tolerance to boron was expressed as a partially dominant character, although the response of an F₁ hybrid, relative to the parents, varied with the level of boron applied. The F₁ hybrids responded similarly to the more tolerant parent at low B treatments and intermediate to the parents at higher treatments. Ratios consistent with monogenic segregation were observed for the F₂ and F₃ generations for the combinations (WI^*MMC) × Kenya Farmer, Warigal × (WI^*MMC) and Halberd × Warigal. The three genes, Bo1, Bo2 and Bo3, while transgressive segregation between two tolerant genotypes, G61450 and Halberd, suggested a fourth locus controlling tolerance to boron.     

Improving the Performance of Wheat by Seed Priming Under Saline Conditions

Salinity is one of a major threat in harvesting good wheat stand on sustained basis. In this study, potential of seed priming techniques to improve the performance of wheat varieties (SARC‐1 and MH‐97) in a saline field was tested. For priming, wheat seeds were soaked in aerated solution of ascorbate (50 mg l^?1; ascorbate priming), salicylic acid (50 mg l^?1; salicylicate priming), kinetin (50 mg l^?1; kinetin priming) and CaCl₂ (50 mg l^?1; osmopriming) for 12 h. For comparison, seeds were also soaked in simple water (hydropriming); in addition, untreated seeds were also taken as control. Seed priming treatments substantially improved the stand establishment; osmopriming (with CaCl₂) was at the top however. Likewise maximum fertile tillers, grains per spike, 1000‐grain weight, grain yield and harvest index were observed in plants raised from seeds osmoprimed (with CaCl₂) followed by ascorbate priming in both the varieties tested. As an index of salinity tolerance, seed priming treatments also improved the leaf K⁺ contents with simultaneous decrease in Na⁺ concentration, osmopriming being the best treatment. Similarly, maximum total phenolic contents, total soluble proteins (TSP), α‐amylase and protease activities were observed in osmoprimed (with CaCl₂) seeds followed by ascorbate priming. Economic analysis also indicated that osmopriming is more viable with maximum net return and benefit‐to‐cost ratio. In conclusion, different seed priming treatments in wheat seeds improved the salinity tolerance nonetheless osmopriming (with CaCl₂) was the most effective treatments to get higher grain yield and net return in both wheat varieties whereas kinetin was the least effective.     

Salinity Effects on the Growth and Ion Contents of Some Chickpea (Cicer arietinum L.) and Lentil (Lens culinaris Medic.) Varieties

The effect of salinity on seed germination, plant yield parameters, and plant Na, Cl and K concentrations of chickpea and lentil varieties was studied. Results showed that in both crops percentage emergence was significantly reduced by increasing NaCl levels (0–8dSm^?1). From the plant growth studies it was found that differences existed among chickpea and lentil varieties in their response to NaCl application. In chickpea, the variety Mariye showed the comparatively lowest germination percentage and the lowest seedling shoot dry weight in response to salinity and was also among the two varieties which had the lowest relative plant height, shoot and root dry weight and grain yield at maturity. Similarly, variety DZ-10-16-2, which was the second best in germination percentage and the highest in terms of seedling shoot dry weight, also had the highest relative plant height, shoot and root dry weights, and grain yield at maturity. In lentil, however, such relationships were less pronounced. Chloride concentration (mg g^?1) in the plant parts at salt levels other than the control was about 2–5 times that of Na. K concentration in the plants was significantly reduced by increasing NaCl levels. Chickpea was generally more sensitive to NaCl salinity than lentil. While no seeds were produced at salinity levels beyond 2dSm^?1 in chickpea (no seeds were produced at this salt level in the most sensitive variety, Mariye), most lentil varieties could produce some seeds up to the highest level of NaCl application. Overall, varieties R-186 (lentil) and Mariye (chickpea) were the most sensitive of all varieties. On the other hand, lentil variety NEL-2704 and chickpea variety DZ-10-16-2 gave comparatively higher mean relative shoot and root dry weights, and grain yield, thus showing some degree of superiority over the others. The observed variations among the varieties may be useful indications for screening varieties of both crops for salt tolerance.