Number Of Achenes Research Articles

Moisture content and mycorrhizal fungi in maternal environment influence performance and composition of Lallemantia species offspring

The availability of soil water content and nutrition in the maternal plant environment plays pivotal roles in shaping the performance, physio-biochemical properties, and chemical composition of the produced seed. This study aimed to investigate the effects of water and arbuscular mycorrhizal fungi (AMF) of maternal plant environment on performance, physio-biochemical properties, and chemical compositions of Lallemantia species offspring. A split-factorial experiment was performed using a randomized complete block design (RCBD) with three replications. The main plot consisted of three drought stress (30 %, 60 % and 90 % of soil available water depletion). The subplots were the factorial combination of arbuscular mycorrhizal fungi (AMF− and AMF+) and Lallemantia species (L. iberica and L. royleana). The offspring of both Lallemantia species experienced a decrease in seed performance, superoxide dismutase, catalase, ascorbate peroxidase enzyme activities, proline, and chemical composition as well as a rise in hydrogen peroxide and lipid peroxidation due to the limited availability of water in the maternal plant environment. On the other hand, providing adequate nutrition in the maternal plant environment resulted in improved germination index, increased starch, and oil content, as well as higher levels of nitrogen and phosphorus in the offspring of both Lallemantia species. Compared to the offspring of L. royleana, the offspring of L. iberica had a higher number of achenes, seeds, seed weight, larger seed size, greater germination index, and higher levels of starch, oil, nitrogen, phosphorus, potassium, and calcium. In contrast, the offspring of L. royleana exhibited higher longevity, enhanced germination under osmotic and salinity stress, increased proline levels, and higher activities of antioxidant enzymes such as superoxide dismutase, catalase, and ascorbic peroxidase as well as sucrose and total soluble sugar. The study concludes that the best seed performance, antioxidant enzyme activities, and carbohydrate levels were observed in the offspring of both Lallemantia species produced under 60 % soil available water depletion with AMF inoculation in the maternal plant environment. These findings highlight the significant impact of the soil available water depletion and AMF inoculation on the seed performance, physio-biochemical properties, and chemical composition of the offspring, providing valuable insights for optimizing seed production and performance.

Comparative Analysis of Morphological and Biochemical Traits in Fragaria × ananassa (Cv. Chandler) under Varied Cultivation Systems

The present research was carried out at Khalsa college Amritsar during 2018-19 to investigate the effect of different cultivation systems on the morphological and biochemical attributes of strawberry cv. Chandler under subtropical conditions of Punjab. The experiment was laid out in Randomized Block design by using eight treatments, each comprising three replications. The different planting systems including flat beds, raised beds, ridges, soilless media, polythene bags, cement pots, plastic crates and low poly tunnels were employed during this research. The runners of strawberry collected from Dr Y S Parmar University of Horticulture and Forestry, were utilized for the experiment. The morphological parameters such as fruit size, weight, number of achenes and biochemical parameters like Total soluble solids, acidity, sugars and ascorbic acid content were analyzed. The results of this present study revealed that maximum fruit length, breath, number of achenes were observed underlow poly tunnels. Similarly, the maximum TSS, total sugar content, ascorbic acid and minimum acidity level was recorded under low under poly tunnels. These outcomes strongly suggest the superiority of utilizing low poly tunnels for strawberry cultivation, emphasizing their potential to enhance both morphological traits and biochemical compositions compared to the other employed planting systems.

NITROGEN USE EFFICIENCY IN SUNFLOWER (HELIANTHUS ANNUUS L.) INFLUENCED BY VARIOUS FERTIGATION AND BED PLANTING TECHNIQUES

Low nitrogen fertilizer use efficiency and high losses of nitrogen are the critical challenges being faced by sunflower grower. To address these concerns, an experiment was carried out during spring 2021 at the Agronomic research area of the Agriculture University, Faisalabad. The randomized complete block design experiment was used with three replications under split plot arrangement. The 5m x 3m net plot size was kept with sowing procedures retained in the main plot and nitrogen application techniques kept in the sub plot. The experiment was planted on 20-02-2021. The matured crop was reaped on 18 June, 2021 manually. The single row hand drill was used to sow sunflower crop. The 75 cm line to line and 25 cm plant to plant distance was maintained. The results indicated that plant population ranged from 73 to 74 with maximum plant height of 174.33 cm, stem diameter (3.70 cm), head diameter (23.13 cm), number of achenes per head (1237.6), 1000-achene weight (68.17 g), highest biological yield (10.92 t ha-1), achene yield (3.22 t ha-1), harvest index (29.48 %) and protein contents (29.03 %) was observed in treatment where nitrogen was applied by fertigation method and sunflower was sown on beds. But maximum oil contents (41.78 %) were observed where nitrogen was side dressed and flat sowing technique was adopted for crop sowing. It is found that use of fertigation method of nitrogen application and bed planting techniques proved to be the best combination for improving growth, yield & yield relating attributes and improve fertilizer use efficiency with lower nitrogen losses for sunflower (Hybrid-33) under agro-climatic conditions of Faisalabad.

Artificial defoliation and its impact on the agronomic performance of sunflower in a non-preferential season

The objective of this work was to evaluate the partitioning of photoassimilates in sunflower plants sown in a non-preferential season coincident with the occurrence of fallow areas in the region, submitted to artificial defoliation with 100% intensity, in different phenological stages of the reproductive period. The experimental design used was randomized blocks with six treatments and three replications, consisting of 18 experimental units and all plants were defoliated. The treatments performed were artificial defoliation, I: No defoliation (control); II: Defoliation at the R1 phenological stage; III: Defoliation at the R3 phenological stage; IV: Defoliation at the R5 phenological stage; V: Defoliation at the R7 phenological stage and VI: Defoliation at the R8 phenological stage. Artificial defoliation performed at 100% intensity at different phenological stages influences the morphological attributes and yield components of sunflower in a distinct way. Defoliations performed at R1 phenological stage have a negative effect on most of the variables analyzed, which provided lower plant height, stem diameter, capitulum diameter, number of rows of achenes, number of achenes per row, achene length, achene width, thousand achene mass and, consequently, in grain yield. This phenological stage was marked by the beginning of the reproductive period, which has a high demand for photoassimilates to maintain plant metabolism and yield. Defoliation performed at R8 phenological stage had better performance for plant height, capitulum diameter, capitulum mass, number of rows of achenes, number of achenes per row, number of plants per hectare and grain yield (>1000 kg ha-1). The plants of experimental units without defoliation had results similar to those defoliated in the R8 phenological stage, however, they still had better performance for thousand achene mass, achene length, achene width, volume index and even a smaller diameter of missing seeds.

Exploring the effect of zinc and boron application on oil contents, protein contents, growth and yield of sunflower

Sunflower is sensitive to boron (B) and zinc (Zn) deficiency when grown on deficient soil, A field experiment was conducted to determine the main and interactive effects of soil applied Zn and B on total production of sunflower at Agronomic Research Area, University of Agriculture, Faisalabad. Experiment was laid out in randomized complete block design (RCBI) with factorial arrangement using three replications with net plot size of 6 m x 4.5 m. The soil application of variable levels of Zn (0, 10, 20 and 30 kg ha-1) and B (0, 1, 2 and 3 kg ha-1) in the form of zinc sulphate and boric acid, respectively were applied at time of sowing. All other agronomic and plant protection practices were kept uniform. The data regarding growth, yield and quality parameters were noted by using standard procedures. Results showed that Zn @ 20 kg ha-1 and B @ 3 kg ha-1 significantly increased the number of plants per plot at harvest, stem diameter, head diameter, number of achenes per head, 1000-achene weight, biological yield and days to maturity, achene yield kg per, harvest index, leaf concentrations or Zn at heading stage, leaf concentrations of B at heading stage (ppm), achene oil content (%), achene protein contents as compared to control. This study concluded that higher growth and yield of sunflower can be achieved by application of Zn at 20 kg ha-1 and B at 3 kg ha-1 under Faisalabad conditions.

Effect of Foliar Application of Boron, Zinc and Manganese on Growth, Yield and Oil Contents of Sunflower (Helianthus annuus L.)

A field trial was conducted to assess the effect of exogenously applied boron, zinc and manganese on growth, yield and oil contents of sunflower at Research Area, University of Agriculture, Faisalabad during Spring, 2019. Randomized Complete Block Design (RCBD) was used for the allocation of treatments with 3 replications. Seed was sown using dibbler on 75 cm apart ridges. Foliar treatments included T0= Control, T1= Water spray, T2= 0.6% boron (B), T3= 0.6% zinc (Zn), T4= 0.6% manganese (Mn), T5= 0.3% B+0.3% Zn, T6= 0.3% B+0.3% Mn, T7= 0.3% Zn+0.3% Mn and T8= 0.2% B+0.2% Zn+0.2% Mn). Boron, Zinc and Manganese were sprayed at 35 days and 55 days after sowing keeping Borax (H3BO3), Zinc Sulphate (ZnSo4) and Manganese Sulphate (MnSo4) as sources of B, Zn and Mn, respectively. Various phenological, physiological and agronomical traits were monitored and analysed. Spray of 0.2% B+0.2% Zn+0.2% Mn gave the high values of traits including number of achenes per head, 1000-achene weight (g), achene yield (kg ha-1), biological yield (kg ha-1), harvest index (%), oil yield (kg ha-1) and achene-oil content (%).

Magnetic Seed Treatment Modulates Phenolic and Fatty Acid Metabolism of Sunflower under Water Scarcity

Environmental and anthropogenic activities are pushing the earth towards warmer years, which is reducing agricultural land and causing water scarcity. It is well documented that sunflower (being drought tolerant) crops can be grown under water deficit conditions with some additional supportive priming applications to compensate for drought-induced challenges. However, finding the most efficient and eco-friendly priming tools is always a top priority among researchers to improve plant growth, adaptive traits, and productivity. In this study, an experiment was performed on oil-producing crops (sunflower) using seed magnetic treatment. The seeds were subjected to 0.1, 0.2, and 0.3 Tesla for 20 min, respectively. Plants were exposed to water limitation (100 and 50%) after 30 days of germination. Sunflower showed its tolerance to water limitation by maintaining the majority of growth parameters, nutritive value, metabolizable energy, and higher proline content. Nevertheless, a reduction in the achene number per capitulum, capitulum weight, chlorophyll, catalase activity, unsaturated to saturated fatty acids, anthocyanin, and hydroxyl derivatives of cinnamic acid supported our hypothesis about the need for some supportive techniques. Better metabolic adjustment and percentage of oil yield were manifested by 0.3 T magnetic seed treatment, which was used for phenolic and fatty acid profiling. To conclude, magnetic treatment of seeds may improve their primary metabolic capacity and antioxidation potential, which in turn may activate their secondary metabolism as evidenced by an excess of gallic acid, quercetin, benzoic acid, curcumin acid, sinapic acid, and chlorogenic acid.

Grain yield, yield components and nitrogen economy of irrigated second-crop common Buckwheat (Fagopyrum esculentum Moench) in a cold-temperate region

Common buckwheat (Fagopyrum esculentum Moench) is a species with great nutritional value and promising to be cultivated as a second crop in irrigated fields of cold-temperate regions with short growing seasons. However, little information exists regarding the nitrogen (N) economy of common buckwheat as a second crop following a high-yielding winter cereal. This study aimed to quantify grain yield, its components, and the grain protein content, and to evaluate N economy processes such as the initial N use efficiency (INUE), the N uptake efficiency (NUptE), the N internal efficiency (NIE) for biomass and grain yield and the N harvest index (NHI) among different treatments of N availability at sowing in four site-year experiments of common buckwheat as a second crop in irrigated fields of the southwestern Pampas of Argentina. The variety Mancan, used in this study, lasted between 73 and 92 days (888–1073 °C days) from sowing to harvest. Grain yield was highly correlated with achene number but not with achene weight. Grain yield ranged from 405 to 2725 kg ha-1, with an interaction between treatments and experiments, with major differences among experiments and minor differences among N availability treatments. Relative N uptake was maximized at a higher value of N availability (160 kg N ha-1) than grain yield (50 kg N ha-1), associated with higher responses of N uptake, vegetative N uptake and grain protein content than grain yield to N availability. However, NUptE featured a negative response to N availability in all experiments. NHI was highly variable among experiments, ranged between 0.51 and 0.83 and was affected by N availability in only two experiments. NIE for biomass and grain yield were 80 kg kg-1 and 36 kg kg-1, respectively, which were lower than those of most cereals but higher than those of other non-cereal grain crops. A short crop cycle of the variety Mancan, an average grain yield of 1594 kg ha-1 among experiments in this study, a low N availability requirement to maximize grain yield and high values of NIE for biomass and for grain yield suggest that buckwheat is a promising species for second crop sowing in cold-temperate regions.

Salinity tolerance determination in four sunflower (Helianthus annuus L.) hybrids using yield parameters and principal components analysis model

Globally, around 800 million hectares are affected by salinity. This abiotic stress causes plant growth inhibition, disruptions in physiological processes in plant cells, and yield losses in many crops. Sunflower is the third-most oilseed crop globally produced, and it is considered moderately tolerant to salinity. There are few studies about the genotypic variability existing in sunflower for responses to salinity, especially the changes in yield and oil content and quality under salinity. The present work aimed to study the effects of salinity on achene yield in four sunflower genotypes and their components and on the oil content and quality and their relationships. Four sunflower hybrids (ACA885, TRITON MAX, SRM769 and SRM779) were grown at 130 mM NaCl irrigation solution under controlled environmental conditions. The achene yield, the yield components, and the content and oil quality were determined. Based on the four studied genotypes, salinity decreased achene yield by 75.1 %. SRM779CL had a lower achene yield reduction by salinity. Yield component that most explained this tolerance was the number of achenes per plant. SRM779CL was the hybrid with the highest oil percentage loss. Contrarily, salinity increased the oil content in ACA885. Salinity decreased the ratio between oleic (18:1) and linoleic acid (18:2) in all genotypes. Therefore, salt stress increased the percentage of unsaturations in the four genotypes examined in this work. Finally, considering the 12 parameters measured, principal components analysis could determine that SRM779CL showed the best performance under control conditions while ACA885 was the most tolerant under salinity.

Titanium Organic Complex Improves Pollination and Fruit Development of Remontant Strawberry Cultivars under High-Temperature Conditions

Heat stress negatively affects pollination, fertilization, and consequently, the development of strawberry fruits. It was proved that foliar application of titanium organic complex improved pollination and fertilization processes of some plant species, which resulted in better fruit development. Therefore, a three-year experiment was designed to determine the effect of the titanium organic complex on pollination and fertilization processes and consequently on fruit development of three remontant strawberry cultivars grown under canopies, under conditions of high temperature. The experiment demonstrated that high temperature disrupted the flowering physiology of strawberry. Under such conditions, the viability and germination of pollen as well as the receptivity of stigma were significantly reduced. The application of titanium organic complex during flowering had a beneficial effect on the pollination and fertilization processes of strawberries. Plants treated with the titanium organic complex were characterized by higher pollen viability, better pollen germination, a higher number of achenes in fruit, and a higher weight of individual fruit, compared to the not treated plants. The obtained results suggest that application of titanium organic complex during flowering may alleviate the stress caused by high temperature and contribute to the improvement of the quantity and quality of a crop.

Оценка фертильности пыльцы гибридов подсолнечника методом сплит-опыления

The main objective of the study was to study the effect of pollen from sunflower hybrids on the real seed productivity and setting of achenes in CMS-tester plants as the final indicators of pollen fertility. The studies were carried out in 2019 and 2021 at V.S. Pusotvoit All-Russian Research Institute of Oil Crops, Krasnodar. The object of the study was cultivated sunflower plants of Helianthus annuus L.: Oksi and NK Brio hybrids as paternal forms, as well as the sterile hybrid Kubansky 93 and the line VK1-klp A as CMS testers. On one vertical part of a separate head, the pollen of the Oksi hybrid was applied, and on the other, the pollen of the NK Brio hybrid was used, i.e. we applied the split-pollination method. The number of fiiled seeds on the head of the CMS tester when pollinated with the pollen of the hybrid Oksi was significantly less than that of the standard hybrid NK Brio. On average, over two years, a decrease in real seed productivity was observed in the hybrid Oksi by 1.97 times in relation to the hybrid NK Brio. The development of a larger number of achenes to technical maturity led to the progressive growth of a part of the head pollinated by the pollen of the NK Brio hybrid. A similar pattern was also noted for the seed set. On the heads of the CMS-tester, on average for two years, the pollen of the hybrid Oksi showed a significant decrease in the setting of achenes in relation to the standard – by 2.24 times. Our earlier data on the presence of morphological anomalies in the pollen of the Oksi sunflower hybrid are consistent with the facts of reduced seed productivity and seed set when evaluating the pollen quality of this hybrid crossed with the CMS-tester, established in this work. The question remains open at what stages the negative impact of the genetic factors of the reproductive function of the pollen of the Oksi hybrid occurs: pre- or post-zygotic.

Wind dispersal of seeds of Parthenium hysterophorus L. (Asteraceae) contributes to its steady invasion and spread

AbstractWind dispersal is considered to be a potentially important mode of spread for parthenium weed (Parthenium hysterophorus L.), an invasive Asteraceae herb of worldwide significance. However, empirical evidence of the role of wind dispersal on the seeds (achenes) of parthenium weed in natural landscapes is lacking. The results of a simulation study undertaken at a wind tunnel facility, Australia, indicated that the dispersal distance of parthenium weed achenes is largely determined by wind velocity (109–131% increase in distance where wind velocity is doubled) and plant release height (75–80% increase when release height is doubled). Glasshouse harvested achenes released from 1 m in height could travel up to 2 m under a 2 m s−1 wind velocity, with the majority of achenes reaching more than 1 m. Smaller‐sized achenes travelled 5% further than larger‐sized achenes. The terminal velocity was calculated to be 1.256 ± 0.006 m s−1, indicating a moderate wind dispersal ability for the weed. A complementary field study in Southeast Queensland, Australia, indicated that the cumulative wind velocity and wind direction, instead of the mean wind velocity, determined the direction of dispersal of the achenes. Further post‐dispersal surveys suggested the number of achenes outside of a standing population declined rapidly as distance from the population increased. Most achenes were dispersed less than 2 m from their parent plant, while the maximum distance achieved was less than 5 m under natural conditions in North Queensland. In conclusion, the natural wind dispersal of parthenium weed consists of small, but measurable increments each year, thus contributing to the weed proliferation and spread at the landscape scale level.

Environmental Response in Sunflower Hybrids: a Multivariate Approach

Seed yield stability, being strong influenced of environmental factors, remains the most important objective of sunflower breeding. In present research have been assessed 8 yield related traits at 25 sunflower hybrids, in two growing season (2019, 2020), under different weather conditions in Soroca district from the northeast of the Republic of Moldova. The principal component analysis, correlative and multicollinearity statistics highlighted their clustering according to different categories: commercial, experimental and in testing phase for hybrid performance, indicating the diverse nature of hybrids. The correlation profile of yield related traits at the commercial hybrids contrasts with that of the tested and experimental hybrids which in both evaluated years, is more heterogeneous in context of the strength and direction of correlation. The parameters achene weight per head and number of achene per head, followed by seed yield and head diameter have the highest degree of variation related to growing season. Most negative correlations are found for correlation pairs with variables 1000 seed weight and hectolitre mass of seeds, which are moderate and high for the tested and experimental hybrids, and predominantly low for the commercial ones. The commercial hybrids were more sensitive to the drought stress of the 2020 growing season, responding by a greater decrease of the majority of analyzed agronomic indices. At the same time the correlations between different traits indicated a pattern similar to previous year. Contrary, the experimental hybrids and those in the testing phase showed small changes in the values of agronomic traits that suggest a greater tolerance to drought conditions, as well as less correlations between different indices. The results have several implications for the future breeding, genotype evaluation and recommendation of sunflower hybrids for production in the local regions of growth.

Resistance of sunflower lines and hybrids to major pathogenes in the Northern Steppe of Ukraine

The purpose was to establish the manifestation peculiarities of sunflower diseases and their combination with valuable economic traits depending on the genotype, as well as to select the best lines and hybrids for further use in production. To complete this purpose, the following objectives were achieved: to create a stationary infectious background for sunflower; to investigate the manifestation of major diseases of sunflower depending on the year conditions; to assess lines and hybrids for valuable economic characteristics and resistance to several pathogens; to select the best lines and hybrids.
 Materials and methods. The phytopathological studies were conducted on a long-term (2005–2020) sunflower monocrop, against artificial field infectious backgrounds, for the creation of which we used parts of naturally infected plants and laboratory infectious material. We studied resistance of sunflower lines and hybrids to pathogens widespread in the Northern Steppe of Ukraine: downy mildew (Plasmopara helianthi Novot.), dry head rot (Rhizopus nigricans Ehrend) and embellisia blotch (Embellisia helianthi (Hansf.) Pidolp). The infectious background level was determined by calculating the percentage of sunflower plants affected by pathogens related to the total number of sown achenes of an accession. The valuable economic characteristics of the genotypes were determined in accordance with the competitive trial methods. A total of 60 accessions, sunflower lines and hybrids bred by IOC NAAS and PPP nd a V.Ya. Yuriev NAAS, were studied.
 results and discussion. The infectious background level, defined as the percentage of infected plants, fluctuated over the study years. The variability ranges were as follows: for downy mildew in 2005–2020 – 7.2–27.3%; for dry head rot in 2012–2020 – 47.1–82.2%; for embellisia blotch in 2012–2020 – 11.0–88.8%. A line – sterile analogue (ZL70A), a line – pollen fertility restorer (Kh 114 V) and hybrids (Khazar, Koliada, Pervistok and Pryz) with high (score 7 points) or very high (score 9 points) resistance to the three studied pathogens have been identified. High resistance to downy mildew and dry head rot was recorded in line Kh 720 V and simple sterile hybrid KhZ 1701 A. Lines Skh 1008 A, ZL72A, ZL42A, and ZL260V as well as hybrid Haichur were distinguished due to their high resistance to downy mildew.
 During the years of studying valuable economic characteristics (2017–2020), high levels of the infectious backgrounds of the major pathogens of sunflower were observed, which made it possible to identify the best accessions combining high resistance (resistance score 7 and 9 points) with high yield, high 1000-seed weight (up to 58.6 g), high oil content in seeds (up to 52.12%) and low huskness (£ 24.6%). The ‘germination – physiological ripeness’ period in the best resistant hybrids was 95–105 days and, in the lines, it lasted 85–105 days. Hybrid Koliada jointly bred by PPI nd a V.Ya. Yuriev NAAS and IOC NAAS was the best in terms of yield (3.61 t/ha). Since 2020, Koliada has been the State Register of Plant Varieties Suitable for Dissemination in Ukraine.
 Conclusions. A possibility of identifying genotypes (lines and hybrids) with group resistance to the major sunflower pathogens, which are common in the Northern Steppe of Ukraine, has been proven. Lines and their hybrids combining high resistance to the major pathogens with high levels of economic characteristics have been identified.

Safflower assimilate remobilization, yield, and oil content in response to nitrogen availability, sowing time, and genotype

In rainfed cropping systems, crops are typically subjected to terminal stresses, which diminish the assimilation process. Information regarding safflower (Carthamus tinctorius L.) dry matter dynamics during the seed-filling period and its association with yield-forming components is lacking. Field experiments over two years were conducted to assess the influence of nitrogen (N) fertilization levels (0, 100 and 200 kg ha−1), sowing time (autumn vs. spring) and genotype (two hybrids and an open-pollinated variety) on growth, assimilate remobilization, achene- and oil yield of safflower, and to identify early crop attributes as predictors of yield. Greater than 100 kg N ha-1 were required to optimize achene yield (> 4 Mg ha-1). On average, N promoted early growth and increased capitula and achenes per unit area compared with the non-fertilized control. The higher the availability of assimilates at the source, the greater their remobilization to sink (r = 0.823, P < 0.01), which was in turn associated with achene yield (r = 0.53, P < 0.05), provided that a critical sink size (number of achenes) had been established during flowering. Dry matter remobilization efficiency ranged between 29.5 % and 39.1 %. Under favorable conditions, hybrids exhibited higher achene- and oil yield than the variety. Oil yield was almost entirely (98 %) determined by achene yield. Autumn sowing increased the average achene yield (28 %) and oil production (20 %) compared with spring sowing. Harvest index (HI) ranged from 0.17 to 0.35 and was associated with achene yield (r = 0.703, P < 0.01). Achene yield could be predicted by measurements of dry matter at anthesis, while the estimation of biomass from plant height measurements was not applicable in safflower. Findings highlight the value of properly designed cropping systems for safflower production based on environmental variables and crop management practices, which can support high yields and improve N management.

Potassium fertilization improves growth, yield and seed quality of sunflower (Helianthus annuus L.) under drought stress at different growth stages.

Water scarcity is a major concern for sunflower production in the semi-arid and arid regions of the world. Potassium (K) application has been found effective to alleviate the influence of drought stress; however, the impact of drought stress on seed quality of sunflower has not been reported frequently. Therefore, a field experiment was performed to determine the optimum K requirement for mitigating the adverse effects of water stress and improving growth and seed quality of spring-planted sunflower. Sunflower plants were exposed to water stress at different growth stages, i.e., Io = no stress (normal irrigation), I1 = pre-anthesisi stress (irrigation skipped at pre-anthesis stage), I2 = anthesis stress (irrigation skipped at anthesis stage) and I3 = post-anthesis stress (irrigation skipped at post-anthesis stage). Potassium was applied at four different rates, i.e., Ko = 0, K1 = 50, K2 = 100 and K3 = 150 kg ha-1. The results revealed that water stress at pre- and post-anthesis stages significantly reduced plant height, head diameter, number of achenes, oleic acid contents, and phosphorus (P) uptake. However, pre-anthesis stress improved linoleic acid contents. Treatment IoK3 (stress-free with 150 kg ha-1 K) was optimum combination for 1000-achene weight, biological and achene yields, oil contents, protein contents, and N and P uptake. Results indicated that a higher amount of K and irrigation resulted in higher yield, whereas yield and yield components decreased with early-stage water stress. Nevertheless, potassium application lowered the impacts of waters stress compared to no application. Keeping in view these results, it is recommended that sunflower must be supplied 150 kg ha-1 K in arid and semi-arid regions to achieve higher yield and better seed quality.

VARIABILITY OF SUNFLOWER HEAD/CAPITULUM BY NEW MORPHOLOGICAL CHARACTERS

New studies on the morphological characteristics of sunflower plants could provide new systems and directions in the complex progress of the future improvement of hybrids. Through the complex (Encheva &amp; Shindrova, 2014) and wide genetic dowry together with the concrete cultivation conditions of the sunflower, the characteristic expression of the plant morphology takes place. In the recent improved Hysun 162 IT hybrid, some new characters were found, specific to the semi-early maturity group. Thus, the diameter of the sunflower head/capitulum had an average of 17 cm. The weight of the sunflower head was 105 g together with the achenes produced and only 39 g empty head, without achenes. The average of number of achenes/ head was 1470, and their weight was 65 g. The percentage of empty achenes was 2-3%, and the mass of one thousand seeds was on average 44 g. The seeds had a length of 10 mm and width of 5 mm. Positive correlations were generally obtained between the morphological characters of the sunflower head. Though this study carried out on the components of the heads of this new sunflower hybrid, a good adaptability to the current zonal agriculture was found.

Influence of Foliage Applied Zinc on Growth and Yield of Hybrids Sunflower (Helianthus Annus L.)

The aim of study was to evaluate the influence of foliage applied zinc on growth, yield and oil contents of hybrid sunflower. Experimental treatments comprise of two sunflower hybrids viz. H1= Hysun-33 and H2= S-278 and three zinc levels viz. T1= Control (no application), T2=1% ZnSO4 and T3 = 2% ZnSO4. The experiment was laid out in Randomized Complete Block Design (RCBD) with split plot arrangement and repeated thrice. Data regarding growth, yield and oil contents was collected by using standard procedures. Results revealed that sunflower hybrid Hysun-33 gained maximum plant height (210.67cm), stem diameter (2.427), Head diameter (15.533) achene number (852), achene yield (189.19 t ha-1), leaf area (789.56cm2) and oil contents (40.423%) followed by sunflower hybrid S-278. Zinc application significantly improved the yield and oil contents. In this regard, maximum plant height (194.67 cm), stem diameter (2.718cm), head diameter (14.633 cm), achene number (842.17), achene yield (194.56 t ha-1), leaf area (782.5cm2) and oil contents (40.12%) from 2% foliar application of zinc followed by 1% foliar application of zinc. Whereas, minimum plant height, stem diameter, head diameter, achene number, achene yield, leaf area and oil contents were recorded from control where no zinc was applied. Interaction of sunflower hybrids with zinc was also significant. In this contest, maximum plant height (231.67cm), stem diameter (2.917cm), head diameter (15.7cm), achene number (925.0), achene yield (205.89 t ha-1), leaf area (801.33cm2) and oil contents (41.65%) were recorded from sunflower hybrid hysun-33 with 2% application of zinc followed by sunflower hybrid S-278 with 1% zinc foliar application. In Conclusion, sunflower hybrid along with the 2% foliar application of zinc is most suitable combination to achieve higher yield and oil contents.

He-Ne Laser Seed Treatment Improves the Nutraceutical Metabolic Pool of Sunflowers and Provides Better Tolerance Against Water Deficit.

Water-scarce areas are continually increasing worldwide. This factor reduces the quantity and quality of crops produced in affected areas. Physical seed treatments are considered economical and ecofriendly solutions for such problems. It was hypothesized that a moderately drought-tolerant crop grown from seeds treated with a He-Ne laser utilizes water-limited conditions better than plants grown from untreated seeds. A field study was conducted, growing a moderately drought tolerant crop (sunflower) with supportive seed treatment (He-Ne laser treatment at 300 mJ) for 0, 1, 2, and 3 min. Thirty-day-old plants were subjected to two irrigation conditions: 100% (normal) and 50% (water stress). Harvesting was done at flowering (60-day-old plants) at full maturity. The sunflowers maintained growth and yield under water limitation with a reduced achene number. At 50%, irrigation, there was a reduction in chlorophyll a, a+b and a/b; catalase activity; soluble sugars; and anthocyanin, alongside elevated proline. The improved chlorophyll a, a+b and a/b; metabolisable energy; nutritional value; and yield in the plants grown from He-Ne-laser-treated seeds support our hypothesis. Seeds with 2-min exposure to a He-Ne laser performed best regarding leaf area; leaf number; leaf biomass; chlorophyll a, a+b and a/b; per cent oil yield; 50-achene weight; achene weight per plant; carotenoid content; and total soluble phenolic compound content. Thereafter, the leaves from the best performing level of treatment (2 min) were subjected to high-performance-liquid-chromatography-based phenolic profiling and gas-chromatography-based fatty acid profiling of the oil yield. The He-Ne laser treatment led to the accumulation of nutraceutical phenolic compounds and improved the unsaturated-to-saturated fatty acid ratio of the oil. In conclusion, 2-min He-Ne laser seed treatment could be the best strategy to improve the yield and nutritional value of sunflowers grown in water-limited areas.

The effect of pollen source on seed traits and dispersability in the heterocarpic annualCrepis sancta

AbstractAimsThe evolution and expression of dispersal-related traits are intertwined with those of other life-history functions and are manifested within various physiological constraints. Such a relationship is predicted between inbreeding levels and dispersability, which may be anatomically and ontogenetically linked so that the selection pressures on one may affect the other. While both the effect of inbreeding on reproductive success and on dispersal strategies received much attention, only a few studies considered both simultaneously. Furthermore, such studies often rely on two dichotomic representations of breeding and dispersal: using selfing versus outcrossing as a representation of breeding level, and dispersal ratio as the sole representation of dispersal strategy.MethodsHere, we used pollination experiments in the heterocarpic Crepis sancta (Asteraceae) to expand in two different manners on the common practice of using dichotomic representations of breeding and dispersal. First, we used pollination treatments that represent a continuum from selfing through pollination by kin to pollination by a distant neighbor. Second, we measured a whole set of continuous morphological and dispersal-related traits, in addition to measurements of reproductive success and dispersal ratio.Important FindingsThe proportion of developed capitula and the number of both dispersed and non-dispersed achenes were significantly lower in the self-pollination treatment in comparison to the outcrossed treatments. The effect of pollen sources on dispersal ratio was not statistically significant, though self-pollinated plants rarely produced non-dispersing seeds. Achene’s biomass increased with distance between parent plants, but pappus width did not, leading to a nonsignificant effect of pollination on falling velocity. Overall, pollen source affected mainly traits that were associated with reproductive output, but it had no clear effect on predominately dispersal-related traits. Such differences in the response of reproduction and dispersal traits to variation in pollen source suggest that dispersal-related selection is probably weak and/or masked by other forces.