Moisture Stress Environments Research Articles

Variability and Diversity Studies Using Morpho-physiological Traits in Wheat (Triticum aestivum L.) under Irrigated and Rainfed Conditions

A study was conducted at Rice and Wheat Research Centre, Malan and Department of Genetics and Plant Breeding, CSK HPKV, Palampur, Himachal Pradesh, India during October, 2013 to May, 2014 to identify traits for developing reliable selection criteria and conduct diversity analysis. In the present investigation, fifty-six diverse wheat genotypes were evaluated in an alpha-design using various yield attributes and drought indices under irrigated and moisture-stress environments over three environments in two locations. Results from the study indicated significant differences for almost all the traits under all three environments and pooled environments. Variability studies showed high phenotypic and genotypic coefficient of variability with high heritability coupled with high genetic advance for seedling vigour under irrigated conditions as well as under moisture-stress conditions along with membrane stability index, dry matter accumulation and grain yield. On the basis of low DSI and high DRI values and relative ranking of morpho-physiological traits, seven genotypes HPW 368, NI 5439, CM 33, CM 19, HPW 236, CM 11 and HPW 349 have been found to be moisture-stress tolerant. Association studies showed that grains spike-1, harvest index, thousand grain weight, excised leaf water loss and days to 75% maturity are most important traits for selection of tolerant genotypes. On the basis of D2 statistics, 56 genotypes were grouped into twelve main clusters and genotypes HPW 277, HPW 297 and NIAW 1415 were found superior as well as diverse for most of the traits. Hence, these genotypes can be used in breeding programmes aimed at enhancing drought tolerance.

IoT based technological support for moisture stress experimental study on plants with stress prediction using deep learning

BACKGROUND: The increased depletion of ground water resources poses the risk of higher moisture stress environment for agriculture crops. The rapid increase in the moisture stress situation imposes the need of efficient agricultural research on determining the impact of moisture stress on variety of crops. OBJECTIVE: The prime objective of the proposed work is building an IoT based Plant Phenotyping Device for moisture stress experimental study on variety of crops with deep learning model for stress response detection. METHODS: In this work, IoT technology is used for building a proposed system for conducting the moisture stress experiments on plants and adopting the image processing and convolution neural network based model for stress prediction. RESULTS: The accuracy of the proposed system was experimentally evaluated and empirical results were satisfactory in maintaining the desired level of moisture stress. Performance analysis of LeNet, AlexNet, customized AlexNet and GoogLeNet CNN models were carried out with hyper-parameters variations on the leaf images. GoogLeNet achieved a better validation accuracy of 96% among other models. The trained GoogLeNet model is used for predicting the moisture stress response and predicted results were matched with manual observation of stress response. SIGNIFICANCE: The affirmative results of proposed system would increases its adoption for in-house precision agriculture and also for conducting various moisture stress experiments on variety of crops. The confirmative detection of moisture stress tolerance level of plant provides knowledge on minimum level of water requirement for plant growth, which in-turn save the water by avoiding excess watering to plants.

Nanopriming Action of Microwave-Assisted Biofunctionalized ZnO Nanoparticles to Enhance the Growth under Moisture Stress in Vigna radiata.

Bare and stabilized zinc oxide nanoparticles (ZnO NPs) were prepared by a microwave-assisted method and used as a priming agent to improve the morphological, physiological, and biochemical quality of Vigna radiata. The priming action was made under normal and moisture stress conditions. A microwave reactor of 850 watts power was used to heat 30 mL of a nanocolloidal solution at 140 °C for 20 min. The stable spherical ZnO NPs at 50.4 mV with 28.2 nm particle size were generated and capped with different biomolecules, cysteine and PVA, to get biostabilized ZnO NPs at 48.8 and 108.5 nm with ζ potentials of -56.2 and -52.0 mV, respectively, holding distinct morphology. The nanopriming effect was studied in V. radiata seeds for bare ZnO and capped ZnO NPs under normal and moisture stress environments. Cysteine-capped ZnO NPs at 250 ppm showed improved germination (90 and 76%), radicle growth (7.6 and 3.6 cm), seedling Vigor (3064 and 1816), dry matter production (145.06 and 96.92 mg/25 seedlings), and hydrolytic (α-amylase and protease) and antioxidant (peroxidase and superoxide dismutase) enzyme activity under normal and moisture stress conditions. The improved priming action of cysteine-capped ZnO NPs is due to increased cell elongation and cell division in the radicle. The uptake and translocation of ZnO NPs in the V. radiata root are evidenced by the presence of an 11.4 ppm zinc level, which was also supported by EDAX and FITC labeling results.

Halophilic soil microbial strains improve the moisture stress tolerance in oilseed crop by sustaining Photosystem II functionality

The sunflower (Helianthus annus L.) is a vital oilseed crop exposed to drought globally. A vast proportion of research is devoted to the naturally occurring microbes and their interaction with plants to alleviate stress consequences. Halophilic bacterial strains, i.e., Bacillus cereus KUB-15 (accession number NR 074540.1), KUB-27 (accession number NR 074540.1), and Bacillus licheniformis strain AAB9 (accession number MW362506), were isolated. Later, isolated strains were used for sunflower through inoculation. Plants were allowed to grow, and thirty-days-old plants were exposed to fixed moisture stress (40–45%). The functionality of photosystem II, light-harvesting ability, and physiological tolerance of cultivars were examined. Bacterial strains B. licheniformis sustained substantial electron flow in between photosystem II (PS II) and photosystem I (PS 1) that not only favored the passable photosynthetic performance but also enhanced antioxidant enzyme activity under stress condition. Compared to other halophilic strains, Bacillus licheniformis did manage reasonable relative water content (RWC), chlorophyll content index (CCI) and biomass production under stress condition. In comparison to both sunflower cultivars, bacterial inoculation was greatly restored growth and photosynthetic performance in Agsun-5264 than S-278 under moisture stress environment. Hence, it is suggested that that bacterial strain and plants cultivar compatibility are essential aspect for sustainable agriculture production.

​​Assessment of Multiple Tolerance Indices for Moisture Stress in Fenugreek (Trigonella foenum-graecum L.)

Background: Drought and moisture stress is the most limiting factor affecting growth and productivity of crop plants. The genotypes may differ in their ability to withstand drought or moisture stress. Therefore, the research was carried out to identify suitable genotypes in moisture stress environments. Methods: The forty eight genotypes of fenugreek were planted in randomized block design with three replications under two environmental conditions namely, (i) normal irrigation (E1) and (ii) staggered irrigation (E2) during rabi 2016-2017. Eight stress tolerance indices viz., stress tolerance (TOL), stress susceptibility index (SSI), stress tolerance index (STI), mean production (MP), geometric mean production (GMP), yield index (YI), stress susceptibility percentage index (SSPI) and modified stress tolerance index (MSTI) were calculated based on seed yield under moisture stress (Ys) and non-stress condition (Yp). The correlation coefficient and mean rank of stress indices were calculated to identify the moisture stress tolerant genotypes. Result: The seed yield under non-stress condition (Yp) had significant positive association with TOL, SSI, STI, MP, GMP, SSPI and K1STI. The seed yield under stress condition (Ys) had significant positive association with STI, MP, GMP, YI and K2STI, while significant negative association with TOL, SSI and SSPI. The results showed that MP, GMP and STI indices were more effective in identifying high yielding genotypes in both stress and non-stress conditions while TOL, SSI, YI and SSPI under moisture stress condition. Based upon the mean seed yield and stress tolerance indices, the genotypes UM-124, UM-60, UM-55, UM-28 and UM-4 were found tolerant to staggered irrigation conditions. Hence, these genotypes may be used further in breeding programmes for moisture stress tolerance.

QTL analysis in multiple sorghum mapping populations facilitates dissection of the genetic control of agronomic and yield-related traits in sorghum [Sorghum bicolor (Moench)

The genetic architectures of agronomic and yield-related traits are expected to involve multiple loci that are unlikely all to segregate for alternative alleles in a single biparental population. Therefore, the identification of quantitative trait loci (QTL) that are expressed in diverse genetic backgrounds of multiple bi-parental populations provides evidence about both background-specific and common genetic variants. The purpose of this study was to map QTLs for agronomic and yield related traits using three connected mapping populations of different genetic backgrounds, to gain insight into the genomic landscape of these important traits in elite Ethiopian sorghum germplasm. The three bi-parental populations, each with 207 F 2:3 lines were evaluated using an alpha lattice design with two replications under two moisture stress environments. Data analysis was done separately for each population using composite interval mapping, finding a total of 105 QTLs. All the QTLs identified from individual populations were projected on a combined consensus map, comprising a total of 25 meta QTLs for seven traits. The consensus map allowed us to deduce locations of a larger number of markers than possible in any individual map, providing a reference for genetic studies in different genetic backgrounds. The meta QTLs identified in this study could be used for marker-assisted breeding programs in sorghum after validation. Only one trait, reduced leaf senescence, showed a striking bias of allele distribution, indicating substantial standing variation among the lines that might be employed in improving drought tolerance of sorghum.

Sustainable effect of a symbiotic nitrogen-fixing bacterium Sinorhizobium meliloti on nodulation and photosynthetic traits of four leguminous plants under low moisture stress environment.

Sustainable effect of a nitrogen-fixing bacterium Sinorhizobium meliloti on nodulation and photosynthetic traits (phenomenological fluxes) in four leguminous plants species under low moisture stress (20-25% soil moisture content) environment was studied. Sinorhizobium meliloti was isolated from fenugreek (Trigonella foenum-graecum) root nodules, and later, it was cultured and purified. Nodulation and photosynthetic ability in the presence of S. meliloti were tested in four leguminous plant species, that is, kidney bean (cv. lobia-2000), black bean (cv. NM-97), mung bean (cv. NM-2006) and chickpea (cv. Pb-2008). Plants of each species were grown in sterilized soil that was previously treated with 25ml suspension containing S. meliloti at 41×106 CFUml-1 kg-1 pot. One-month-old plants were subjected to low soil moisture stress conditions for 15days, and soil moisture contents were maintained to 20-25% throughout the experimental period. The ability to fix nitrogen, nodule formation, and their subsequent effect on phenomenological fluxes in low moisture treated legumes were studied.

Tef (Eragrostis tef) variety development for moisture stress areas of Ethiopia

Worku Kebede, Yazachew Genet, Tsion Fikre, Kidist Tolosa, Solomon Chanyalew , Mengistu Demissie, Kebebew Assefa, Kidu G/Meskel, Atinkut Fantahun & Zerihun Tadele.2020.Tef (Eragrostis tef) variety development for moisture stress areas of Ethiopia.Journal of Innovative Agriculture.volume 7, issue 4, Pages 1-6. Tef is widely cultivated grain crop in Ethiopia by concerning 6.5 million smallholder farmers on about 30% of the full-scale region distributed to cereal crops. The goal of this experiment was to identify and release stable and high yielding tef genotype for moisture stress areas of country and to determine and understand the effect of genotype, environment, and their interaction on grain yield of tef. Fourteen selected tef genotypes obtained from two autonomous crosses and progressed through alternative for a minimum of eight generations, and a local and standard check varieties, were tested over a two years at seven tef growing sites in moisture stress areas of Ethiopia namely Debre Zeit, Alemetena, Dhera, Axum, Sirinka, Minjar and Mehoni, using randomized complete block design with four replications. Among the genotype tested, DZ-Cr-387 x 3774-13(RIL120B) was found predominant in terms of yield at tested moisture stress environments. This genotype was obtained through targeted cross between DZ-Cr-387 (Quncho) selected as a maternal parent for its high yielding capability and wide adaptability and, 3774-13 as a pollen parent for its extraordinarily white seed quality and earliness. The genotype DZ-Cr-387 x 3774-13(RIL120B) gave the average grain yield 2740 kgha-1 pooled across all environments. This genotype

Gene action for oil content and quality in diverse cytoplasmic sources in sunflower under varied moisture environments

Abstract Sunflower breeding aims to developing good heterotic hybrids which can be achieved by tapping combining ability of hybrids belongs to diverse parents. Nine diversified CMS lines along with one maintainer lines were hybridized with four male lines in a line × tester manner thereby, developing a total 40 hybrids. The experimental material was grown over two environments i.e. recommended irrigation and other moisture stress environments continuously for two years 2011 and 2012 in randomized complete block design with three replications at Punjab Agricultural University, Ludhiana, Punjab, India. The experiment was design to estimate combining ability of parental lines, gene effects and effect of divers CMS sources on oil content and quality traits. It was observed that the non-additive component of genetic variance played major role in inheritance of these traits as recommended by analysis of variance of combining abilities and analysis of genetic variance components. Further supporting this conclusion was the fact that the GCA/SCA ratio for oil content and quality traits observed in F1 generation was less than one under both the environments. These results indicated the preponderance of dominant gene action and the feasibility of hybrid sunflower development. GCA estimates revealed that CMS analogues CMS-XA (Unknown), ARG-2A (H. argophyllus) and PRUN-29A (H. praecox spp. runyonic) were very good combiner for oil content under both the environments. The pollen parents RCR-8297 and P69R were observed as very good combiners for oil content and stearic acid under moisture stress condition. The male parent P100R was recorded very good combiner for oil content under normal environment while, RCR-8297 and P100R were very good combiners for oleic acid under both the environments. A total seven crosses were identified for oil content and eight crosses for oleic acid as having high SCA effects under both the water regimes.

English

The study was conducted to characterize early maturing sorghum genotypes under moisture stress and non-stress environments based on root angle. Phenotyping of 23 early maturing sorghum genotypes was carried out under post-flowering moisture stress and non-stressed environment using randomized complete block design (RCBD) in two replications at Werer Agricultural Research Center in 2018 off season. The genotypes were selected based on root angle data that varied from 13.0 to 26.75°. The analysis of variance revealed significant variation among genotypes for most of the traits. Post-flowering drought reduced grain yield by 21% and all the traits showed a reduction in value except flag leaf area. Grain yield showed positive correlations with seedling vigor, grain filling rate, thousand grain weight and panicle weight while negative correlations with number of fertile tiller and panicle exertion for both environments. Root angle revealed positive correlation with grain yield, grain filling rate and thousand grain weight while there was negative phenotypic correlation with panicle exertion in the stressed environment. Therefore, selection for high correlated traits could aid breeding program to develop genotypes with superior yield under both environments flag leaf area, chlorophyll content, harvest index and root angle traits could be used as morphological marker for drought tolerance screening in sorghum since there was positive correlation with yield observed for stressed environment only. The result revealed the importance of intermediate to slightly wider root angle for drought tolerance of early maturing sorghum genotypes by enhancing lateral water absorption of the roots under silty clay soil. Key words: Correlation, early maturing sorghum, morphological marker, post-flowering drought, root architecture, root traits.

Physiological screening of cotton (Gossypium hirsutum L.) genotypes against drought tolerance

Cotton is a vital fiber and oilseed crop badly affected by soil moisture deficit stress. Screening of cotton germplasm is a prerequisite to classify the cotton genotypes as a drought sensitive and tolerant. With the aim to separate the distinct genotypes, eight cotton genotypes (BH-190, Ali Akbar-802, NIAB-86, NIBGE-115, FH-942, IUB-13, MNH-886, and FH Lalazar) were grown under normal moisture (08 irrigations/ 28 acre inches) and moisture stress (03 irrigations at 60, 90 and 120 DAS/ water deficit of 15 inches) environments. The assessment was done through different physiological parameters (stomatal conductance, osmotic and water potential, photosynthetic rate, relative water contents and canopy temperature). Cell injury and yield were also evaluated. The experimental design was Randomized Complete Block Design (RCBD) in factorial way with three replicates. The data obtained was investigated statistically at 5% probability and Least Significant Difference (LSD) test was used to isolate the significant means (treatment). The results indicated that water stress adversely reduced the values of all the above stated parameters. The cotton genotype BH-190 had significantly greater (p<0.05) yield and physiological attributes and found extra water deficit stress tolerant. While cotton genotype FH Lalazar had least value of these attributes as compared to all remaining cotton genotypes and thus considered as water deficit stress sensitive genotype. So, it can be concluded from the results of this experiment that the physiological screening of low soil moisture stress tolerant varieties could be a superior way to mitigate impact of drought stress on the cotton cultivated in drought susceptible regions. Keywords: Cotton (Gossypium hirsutum L.); Drought tolerant; Physiological; Screening http://dx.doi.org/10.19045/bspab.2020.90017

Evaluation of teosinte derived maize lines for drought tolerance

Maize Plants grown in subtropical and temperate regions are often subjected to moisture stress. the wild progenitors of the crop species are the important source of genes of various abiotic and biotic stress tolerance. teosinte (Z. mays ssp. parviglumis), the progenitor of maize possesses several important genes of agronomic importance, majority of which were lost during the process of domestication. In the present investigation, 203 modern maize BC1F2 introgressed lines (encoded as am-1 to am-203) were developed and evaluated under irrigated and moisture stressed environments. In order to introduce the genes of agronomic importance from the progenitor teosinte to modern maize, DI-103 inbred were crossed with teosinte. the present study involved evaluation of 203 lines (encoded as am-1 to am-203). these lines were grown in a single row in two environmental conditions i.e. irrigated and stress condition during Rabi 2016–17 for the phenotyping of morpho-physiological traits viz., anthesis silking interval (ASI), leaf rolling, leaf firing, canopy temperature depression (CTD), chlorophyll content, ear length, ear diameter, kernel rows/ear, kernels/row, tip filling, grain filling, grain yield per plants (g), and 1000-kernel weight and drought tolerance index, stress tolerance index, yield index associated with drought tolerance. Overall sum of rank scores over thirteen traits associated with drought tolerance revealed that am-39 was the most drought tolerant line among all the 203 lines under study with a total score of one hundred eight, followed by am-64, am-16, am-42, and am-102, whereas, am-116 was the most susceptible, with the least score of thirty-four.

EVALUATION OF DROUGHT TOLERANCE IN NEW COTTON CULTIVARS USING STRESS TOLERANCE INDICES

Drought is a wide-spread problem seriously influencing production and quality ofcotton (Gossypium hirsutum L.), but development of resistant cultivars is hamperedby the lack of effective selection criteria. The objective of this study was toevaluate the ability of several selection indices to identify drought tolerant cultivarsunder different environmental conditions. Thirteen cotton cultivars were evaluatedunder both moisture stress (2016) and non-stress (2013) field environments using arandomized complete block design for each environment. Six drought toleranceindices including stress susceptibility index (SSI), stress tolerance index (STI),tolerance index (TOL), mean productivity (MP), geometric mean productivity(GMP) and mean harmonic productivity (HMP) were used. The significant andpositive correlation of yield of genotype under non-stress condition (Yp) and MP,GMP and STI showed that these indices were more effective in identifying highyielding cultivars under different moisture conditions. The results of calculatedgain from indirect selection in moisture stress environment would improve yieldbetter than selection from non moisture stress environment. Coton breeders should,therefore, take into account the stress severity of the environment in choosing anindex. The varieties Viki and Avangard-264 had the highest yields under non-stressconditions. Vega and Chirpan-539 varieties had a low yield potential and showed ahigh stress tolerance to drought.

Biology of Amaranths

Amaranthus, a cosmopolitan genus including endangered species, restricted endemics and widespread weeds, is often difficult to characterize taxonomically and thus has generally been considered by systematists as a “difficult” genus. Species in this genus have high genetic variability, with diversity in growth form, plant height, number of inflorescences, seed colour, protein content, seed yield, resistance to pests and diseases, and adaptation to soil type, pH, climate, rainfall and day-length. The combination of various anatomical characteristics of Amaranthus, such as Kranz anatomy, well developed root system, stomatal conductance, and maintenance of leaf area, results in increased efficiency of using CO2 under a wide range of temperatures, and higher light intensity and moisture stress environments which enables this plant to adapt under diverse geographic and environmental conditions. Buried seeds of Amaranthus constitute an important part of the soil seed bank and position, distribution and dormancy type of these seeds in the soil play an important role in their germination and subsequent emergence, which is further influenced by factors like temperature, soil moisture, and light availability. The current review highlights the positive as well as negative role of the various species of genus Amaranthus. Many species of the genus are medicinally important and bear antiallergic, anticancer, antihypertensive and antioxidant properties, thus being used in the treatment of several aliments. Amaranthus being a rich source of fatty acids, proteins, micronutrients, vitamins and squalene, are used as cereals, dye plants, forages, medicinal plants, ornamentals, and as vegetables. However some of the Amaranthus species are noxious weeds which are known to compete with many economic crops in different parts of the world and cause great yield losses. Thus, further research is warranted to strike a balance between the beneficial and harmful species of this Pseudocereal. Moreover, understanding the weedy behaviour of these plants would provide valuable information for improving our mechanistic models of crop-weed competition and weed population dynamics.

Genetic variation and trait association of tef [Eragrostis tef (Zucc.) Trotter] evaluated under optimal and moisture stressed environments

Tef ['Eragrostis tef' (Zucc.) Trotter] is one of the major cereal crops grown in the Horn of Africa for food and as an export commodity for its unique nutritional qualities. Moisture stress is the leading yield limiting factor of tef production in northern Ethiopia. The objectives of this study were to assess the genetic variability present among 144 tef genotypes of varied population and to identify important agronomic traits with high heritability and correlations for effective breeding. The genotypes were evaluated using four experiments laid down in a 12 x 12 lattice design under moisture stressed and non-stressed conditions in the northern Ethiopia. Main shoot panicle seed weight had high genotypic coefficients of variation (GCV) of 22.4% and 25.9% under non-stressed and stressed conditions, respectively. Grain yield had GCV values of 17.6% and 20.0% in the corresponding environments. Heritability was highest under optimum condition than the moisture stressed, which is valuable to conduct effective selection. A path-coefficient analysis indicated that direct selection for high biomass, harvest index and late maturity could increase grain yield under optimal conditions, while under moisture stress conditions early maturity, high biomass and harvest index were important direct selection criteria for tef breeding aiming for drought tolerance.

Evaluation of selection indices for drought tolerance in some bread wheat genotypes

This study was undertaken to evaluate various selection indices of moisture stress and their applicability in identifying drought stress tolerant wheat genotypes which can acclimatize to various moisture stressed environments in different wheat growing agro climatic zones of Gujarat. Advance lines of wheat genotypes were tested under moisture stress condition of different irrigation regimes. Two sets of irrigation regime i.e one set as irrigated and second as limited irrigation. Ten wheat advance lines along with five check varieties were tested for water stress tolerance at two locations representing North Gujarat and Saurashtra region. Stress intensity at both the locations was markedly differed which indicates differences in soil type, properties and environmental conditions. On the basis of this study, it can be concluded that along with SI, the use of stress indices follows the order of DSI, STI, MP and GMP for selection of drought tolerant genotypes under stress conditions and they may be used to screen wheat varieties tolerant to moisture stress conditions. On the basis of findings of these indices wheat varieties GW 487, GW 488 anf GW 173 were found having higher stress tolerance and with better yield potential under both normal and restricted irrigation conditions. The irrigation criteria under stress condition at Junaghadh location may be revised.

Physiological characterization and grain yield stability analysis of RILs under different moisture stress conditions in wheat (Triticum aestivum L.)

Drought stress is the major environmental constraint contributing to grain yield instability of wheat. In the present study, the recombinant inbred line population derived from DBW43/HI1500 cross was characterized for various morpho-physiological traits as well as grain yield stability analysis under moisture stress. The population was evaluated for grain yield under three different moisture stress environments viz., restricted irrigation, rainfed and late sown rainfed during the cropping season of year 2013–2014. Based on principal component analysis, the first five components explained over 60.40% of genetic variation. Grain yield per plot showed significant correlation with biomass and physiological traits viz., NDVI3, NDVI4, NDVI5, CT1, CT2 and CT3. The combined analysis of variance on grain yield data showed that mean squares of environments, genotypes and GEI were highly significant (p < 0.01). To determine effects of GEI on grain yield, data were subjected to AMMI and GGE biplot analysis, which identified G4, G69, G28, G67, G55 and G112 as the most stable and high yielding genotypes. Hence, the physiological traits NDVI and CT can be effectively used to screen out the line for drought tolerance. In addition, the stable wheat genotypes identified could be used in future wheat breeding programme.

Genetic variation in sorghum as revealed by phenotypic and SSR markers: implications for combining ability and heterosis for grain yield

AbstractHybrid breeding relies on selection of genetically unrelated and complementary parents for key traits. The objective of this study was to examine genetic variation and identify unique sorghum genotypes using phenotypic and simple sequence repeat (SSR) markers and to determine their relationships with combining ability and heterosis for grain yield. A total of 32 landraces and four cytoplasmic male sterile (CMS) lines were phenotyped using 25 agro-morphological traits and genotyped with 30 polymorphic SSR markers. The landraces were crossed with four CMS lines using a line × tester mating design. The 128 hybrids, 36 parentals and four check varieties were field-evaluated using a 12 × 14 alpha lattice design with three replications. General combining ability (GCA), specific combining ability (SCA) and heterosis for grain yield were determined. Genetic distance estimates ranged from 0.39 to 0.60 and 0.50 to 0.79, based on phenotypic and SSR markers, respectively. Landraces 72572, 75454, 200654, 239175, 239208, 244735A and 242039B and CMS lines ICSA 743 and ICSA 756 displayed positive and significant GCA effects for grain yield. Based on the SCA effects of yield, lines were classified into three heterotic groups aligned to the different cytoplasmic systems of testers. Lines with high GCA effects rendered hybrids with highly significant SCA effects with high mid-parent heterosis (MPH) for grain yield. Both marker systems were effective in demarcating sorghum genotypes that provided desirable cross-combinations with high combining ability effects and MPH for grain yield. The selected genotypes are recommended as potential parents for sorghum hybrid breeding in moisture stress environments.

Analysis of tolerance indices for germplasm evaluation in safflower (Carthamus tinctorius L.) subjected to terminal drought stress

In order to evaluate quantitative drought resistance criteria in some safflower genotypes, fiftheen genotypes were evaluated both under moisture stress and non-stress field environments using a randomized complete block design for each environment. The genotypes showed significant differences in grain yield and other traits. Grain yield under irrigated conditions was adversely correlated with water deficit condition, suggesting that high potential yield under optimal conditions does not necessarily result in improved yield under stress conditions. Genotypes G64, G92 and PI253527 showed lower yield reduction than the average of other genotypes. Surprisingly, most of the genotypes showed more than 30% yield reduction under drought stress. The positive correlation between TOL and irrigated yield (Yp) and the negative correlation between TOL and yield under stress (Ys) suggest that selection based on TOL will result in reduced yield under well-watered conditions. We conclude that GMP and STI are able to discriminate tolerant group of genotypes under both environments. Therefore, genotypes G47, G64, G42 and S411 are superior genotypes for both environments. Genotypes S310 , S149 and Almaneriz are more suitable for non-moisture stress than moisture-stress environment.

Morpho-Physiological Attributes of Cultivated Wheat Germplasm for high yield potential under Rain fed condition

Wheat is the most important cereal crop and staple diet for more than one third of the world population and contributes more calories and protein to the world diet than any other cereal crop. In view of global climate change drought stress is becoming major constraints for the productivity of wheat and hence the breeding for drought tolerance is gaining more importance. More accurate and precise phenotyping of genetic resources is the demand of the new generation quantitative geneticists and plant breeders as this is the most critical research area which will lead to identification of trait specific donor germplasm. In the present study, Wheat germplasm accessions (1483 acc.) were evaluated at Issapur farm in Augmented Block Design with four checks based on morpho-physiological parameters. Irrigation was provided at Crown root initiation stage (CRI) and afterwards moisture deficit was maintained throughout the crop duration. There was wide variability in wheat germplasm for the phonological, agronomical and physiological traits. This experiment identified correlated traits responsible for high grain yield under rainfed conditionsuch as biological yield, harvest index, days to maturity, spike length, spikelets per spike, grains per spike, cholorophyll content, grain weight and 1000 grain weight. Based on stepwise multiple regression analysis, major role of prediction on yield was found through biological yield, including harvest index, grain weight spikelets per spike and chlorophyll content. Based on predictor variables, accessions were selected and will be further validated under controlled condition and will be used for introgression purpose in the background of elite varieties to enhance yield and its stability under moisture stress environments.