Growth Of Sunflower Research Articles

Phytohormones Producing Acinetobacter bouvetii P1 Mitigates Chromate Stress in Sunflower by Provoking Host Antioxidant Response.

Different physical and chemical techniques are used for the decontamination of Cr+6 contaminated sites. The techniques are expensive, laborious, and time-consuming. However, remediation of Cr+6 by microbes is viable, efficient, and cost-effective. In this context, plant growth-promoting rhizobacteria Acinetobacter bouvetii P1 isolated from the industrial zone was tested for its role in relieving Cr+6 induced oxidative stress in sunflower. At the elevated Cr+6 levels and in the absence of P1, the growth of the sunflower plants was inhibited. In contrast, the selected strain P1 restored the sunflower growth under Cr+6 through plant growth–promoting interactions. Specifically, P1 biotransformed the Cr+6 into a stable and less toxic Cr+3 form, thus avoiding the possibility of phytotoxicity. On the one hand, the P1 strengthened the host antioxidant system by triggering higher production of enzymatic antioxidants, including catalases, ascorbate peroxidase, superoxide dismutase, and peroxidase. Similarly, P1 also promoted higher production of nonenzymatic antioxidants, such as flavonoids, phenolics, proline, and glutathione. Apart from the bioremediation, P1 solubilized phosphate and produced indole acetic acid, gibberellic acid, and salicylic acid. The production of phytohormones not only helped the host plant growth but also mitigated the harsh condition posed by the elevated levels of Cr+6. The findings mentioned above suggest that P1 may serve as an excellent phyto-stimulant and bio-remediator in a heavy metal-contaminated environment.

Influence of Farmyard Manure and Jeevamrutha on Growth and Yield of Sunflower

A field experiment was conducted during Kharif 2017 at ZARS, University of Agricultural Sciences, Bengaluru to study the influence of different levels of Farm Yard Manure (FYM) and Jeevamrutha on growth and yield of Sunflower in red sandy loam soil. There were nine treatment combinations laid out in factorial randomized complete block design, which were replicated thrice. The experimental results revealed that, the application of FYM at 150 per cent nitrogen equivalent and jeevamrutha at 1500 L ha-1significantly influenced growth parameters like plant height, number of leaves, leaf area, leaf area index and total dry matter production. The interaction effect of FYM and jeevamrutha was significant in enhancing the seed yield of sunflower due to improvement in yield attributes like head diameter, number of seeds per head, hundred seed weight and seed yield per plant.

Short-Term Waterlogging Depresses Early Growth of Sunflower (Helianthus annuus L.) on Saline Soils with a Shallow Water Table in the Coastal Zone of Bangladesh

Sunflower (Helianthus annuus L.), which is widely grown globally for its high-quality edible oil, is reasonably salt and drought tolerant but it is susceptible to waterlogging. In the saline coastal zone of the Ganges delta, sunflower is often exposed to sudden heavy rainfall during early growth but plant tolerance to such events is not known. Hence, we evaluated the effect of short-term soil inundation (referred to as waterlogging) for 0, 24, 48 and 72 h on sunflower at emergence, 2-leaf, and 4-leaf stages in early- and late-sown crops under field conditions (saline, clay-textured soil, and shallow groundwater). Waterlogging for 24 h did not affect sunflower at any stage but waterlogging for 48 and 72 h suppressed emergence and growth at the 2 and 4-leaf stages. Waterlogging for 72 h completely prevented the emergence for early sowing, whereas emergence was less affected for later sowing. Shoot and root dry weight were most affected at the emergence and 2-leaf stage, not at the 4-leaf stage. In conclusion, waterlogging caused by more than 24 h soil inundation at up to the 4-leaf stage severely depressed emergence and growth, indicating the need for effective drainage at sowing of sunflower in the low-lying coastal saline zone of Bangladesh.

Effect of Spraying with Water Hyacinth and Silverleaf Extractson Growth and Yield of Sunflower (Helianthus annuus L.)

A field experiment was carried out in one of the special fields Al-Jazirah - Al-Budhiyab located at latitude 38.28° north and longitude 43.19° east, to find out the effect of different concentrations of the extract of the Water hyacinth and silverleaf plants in three varieties of sun flower. The experiment was applied using a split-plate arrangement within an RCBD design with three replications. The main plots were represented by the varieties Ishaqi, Sakha, and Iqmar, and the sub plots included the spray concentrations 0, 5, 15 and 25 mg L-1. The results showed that the Iqmar variety was superior in plant height (179.73 cm) in the spring season, and the cultivar Ishaqi (175.50 cm) in the fall season. The variety also outperforms generously in leaf area (307.4 cm2) in the fall season. As for the extracts, the water hyacinth outperformed the plant height (177.74 and 175.11 cm) in both seasons, respectively. And in the stem diameter (20.45 mm) in the spring season and in the dry weight of the weeds (0.045 and 0.053 g m2) in both seasons respectively. While silverleaf herb extract exceeded the leaf area (213.9 and 271.1 cm2) in both seasons sequentially and the stem diameter (20.86 mm) in the fall season, the silverleaf herb extract reduced the dry weight of the weeds (0.032 and 0.043 g m2) in both seasons respectively. He increased the weight of 1000 seeds (59.25 and 67.20 grams) in both seasons and the total yield (3.26 ton ha-1) in the fall season. The 15 mg L-1 concentration also increased plant height (180.02 cm) and leaf area (208.9 cm2) in the spring season, disc diameter (22.39 cm) in the fall season and the number of seeds (924 seeds per disc-1). While the concentration increased plant height (176.19 cm) and leaf area (276.8 cm2) in the fall season. The concentration outperformed 5 mg L-1 in stem diameter (19.65 and 20.32 mm) in both seasons and increased the weight of 1000 seeds (59.57 and 67.94 g) in both seasons sequentially and the overall yield (4.35 and 3.18 ton ha-1) in both seasons. Sequentially. We conclude that there is a fluctuation in the behavior of the same crop varieties due to the overlap of study factors and in different directions, so it is recommended to individualize the factors in their influence on the varieties to know the behavior of those varieties more accurately.

Effect of Humic Acid on Growth and Yield Indices of Sunflower (Helianthus annuus) in a Saline Soil

Effect of Humic Acid on Growth and Yield Indices of Sunflower (Helianthus annuus) in a Saline Soil

Contribution of biochar and arbuscular mycorrhizal fungi to sustainable cultivation of sunflower under semi-arid environment

• Biochar and AM fungi under reduced irrigation regimes were studied on sunflower. • Sunflower physiological performance, seed yield and oil content were evaluated. • Biochar combined with AM fungi improve growth and physiological plant performance. • Antioxidant enzymes were enhanced in drought stressed plants by biochar and AM fungi. • Biochar and AM fungi application may support sunflower yield under drought climate. Arbuscular mycorrhizal (AM) fungi and biochar have been successfully adopted to improve crop growth and yield under water stressed environments, however, to date little evidence of their combined effects has been reported. Field trials were conducted in 2018 and 2019 growing seasons in northern Iran to evaluate how biochar and AM fungi could improve sunflower ( Helianthus annuus L.) productivity subjected to reduced irrigation regimes. A randomized complete block design was adopted with the following treatments: three irrigation regimes [no deficit irrigation (NDI), moderate deficit irrigation (MDI) and severe deficit irrigation (SDI) that was calculated as the 50, 30, and 10 % of maximum available water, respectively]; three biochar rates [0 (B 0 ), 2.5 (B 2.5 ) and 5 (B 5 ) t ha −1 of biochar]; and two AM fungi inoculations [inoculated (AM + ) and no-inoculated (AM-) plants]. All treatments were replicated three times. Before plowing, biochar (B 2.5 and B 5 ) was uniformly distributed on the soil surface to incorporate in the soil profile, while AM fungi (AM + ) were distributed in the furrow of sunflower rows before sowing. Biochar and AM fungi were not applied in B 0 and AM- treatments, respectively. Sunflower growth rate, pigments, photosynthesis rate and associated aspects, minerals content, antioxidant enzymes, abscisic acid, total phenolics and seed yield were measured. The results showed that growth parameters, radiation use efficiency, leaf pigments and seed yield decreased under irrigation regimes (NDI > MDI > SDI), while malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ) showed opposite trends. The combination AM fungi and biochar enhanced antioxidant enzymes activities, osmoprotectants, nutrient content and relative water content resulting in a significant decrease in oxidative damage in the drought stressed plants. Seed yield ranged from 4.95 to 1.78 t ha −1 and it was increased by the biochar application (+9% and +7% in B 2.5 and B 5 , respectively) and AM fungi inoculation (+21 % in AM + ) in all irrigation regimes. Overall, the plant's performance observed in the MDI-B 5 -AM + was similar to that in NDI-B 0 -AM- indicating that AM fungi and biochar allow a reduction of water irrigation while maintaining crop yield. According to results, the combination of AM fungi and biochar rate should be adopted as a water-saving practice for sustainable production of sunflower cultivated in semi-arid environments, even if further studies should be carried out to evaluate their effects on other crops and environments.

Phytoremediation of Spent Oil and Palm Kernel Sludge Contaminated Soil Using Sunflower (Helianthus annuus) L

This study was carried out to investigate the phytotoxicity of spent engine oil and palm kernel sludge on seed germination, seedling early growth and survival of sunflower (Helianthus annuus L) and its phytoremediating potential. 8.0 kg topsoil mixed with 2, 4, 6, 8 and 10% (w/v) of spent engine oil and palm kernel sludge, while the control was not mixed with spent oil and sludge (0%). The seeds were sown on these soils and monitored daily. Parameters taken were; plant height, leaf number and stem girth. The result showed that spent engine oil treated plants adversely affected growth compared to palm kernel sludge plants and control which performed better. For plant height, the mean stem girth for control at 2nd week was 0.40±0.05 mm, spent engine oil was 5.96±0.97 palm kernel oil effluent was 14.73±1.16 and at 12th week, control was 1.30±0.05 while for SEO the plant had withered and 124.6±9.02 for POE. Number of leaves at the 12th week was 26.00±2.08 in the control, 8.66±0.66, for spent engine oil at 4%, while for palm oil effluent it was 27.66±0.66, at 4%, concentration respectively. Stem girth at 2 weeks for spent engine oil was 0.19±0.05 at 2%, 0.43±0.03 for palm kernel oil effluent and at the 12th week of planting at 10% concentration was 1.63±0.08 for palm kernel oil effluent, and all plants had withered off for spent engine oil at same concentration at the 12th week. Also, spent engine oil at all concentrations delayed the germination of Helianthus annuus by 2days compared to control. Comparison analysis test showed that growth in untreated plants were significantly higher (p>0.05) than spent oil and palm kernel sludge treated plants. Similar result was observed for leaf number and stem girth which had higher mean value in palm kernel sludge and control compared to spent oil. Sunflower grown in 8% and 10% palm kernel sludge contaminated soil also flowered eight days earlier than control plants, while spent oil treated plant did not. The result shows that sunflower cannot tolerate high (4%, 6%, 8% and 10%) concentrations of spent engine oil in soil compared to palm oil effluent. Therefore, spent engine oil should be properly disposed because of its adverse effect on the growth and yield of sunflower.

Coupling effects of water and nitrogen on photosynthetic characteristics, nitrogen uptake, and yield of sunflower under drip irrigation in an oasis

An experiment was conducted in an oasis area in northwest China to assess the coupling effects of water and nitrogen supply through drip irrigation on photosynthetic characteristics, nitrogen uptake, and yield of sunflower (Helianthus annuus L.), as well as the nitrate distribution in the root-zone soil. The experiment included three irrigation levels (210 [W1], 300 [W2], and 390 [W3] mm), three nitrogen levels (162 [N1], 232 [N2], and 302 [N3] kg/hm2), and control treatment (no fertilization during whole growth period and only irrigated at the budding stage). A nitrogen content over-accumulation in the soil was observed under the low irrigation amount with high fertilizer supply, which cannot enhance the sunflowers’ absorption of nitrogen. Excessive irrigation caused leach of the soil nitrogen, reduced nitrogen content in the root-zone soil (0-40 cm) and limited nitrogen uptake by the crop. Although low irrigation amount with high fertilizer supply can increase the nitrogen content in the soil, it cannot enhance the sunflowers’ absorption of nitrogen. At the vegetative stage of sunflower growth, the accumulation of nitrogen in the organs was mainly concentrated in the leaves, while it was transferred to the flower disk at the reproductive growth stage. Reasonable coupling of water and nitrogen improved the transport of nitrogen from leaves and stems to the flower disk aromoted the formation of yield components. Six regression equations were established with irrigation and fertilization amount as independent variables, and seed rate, seed weight per flowerdisk, 1000 grain weight, yield, water use efficiency and nitrogen partial factor productivity as dependent variables, respectively. Multiple regression and spatial analysis suggested that the irrigation amount of 241.62- 253.35 mm and the fertilization application of 202.02-209.40 N kg/hm2 was a good irrigation strategy, under which all six factors exceed 75% of their maxima, and the yield of sunflower reached 3 229.3 kg/hm2. Keywords: fertilization, Helianthus annuus L., irrigation management, nitrogen transformation, nutrient uptake, Xinjiang DOI: 10.25165/j.ijabe.20211405.6399 Citation: Wang T Y, Wang Z H, Wu Q, Zhang J Z, Quan L S, Fan B H, et al. Coupling effects of water and nitrogen on photosynthetic characteristics, nitrogen uptake, and yield of sunflower under drip irrigation in an oasis. Int J Agric & Biol Eng, 2021; 14(5): 130–141.

Effects of AMF on nutrient and stoichiometric characteristics in different organs of sunflower

In order to explore the effects of arbuscular mycorrhizal fungi (AMF) on growth and nutrient absorption for ornamental sunflowers, explain the related physiological mechanism, four species of AMF Acaulospora scrobiculata (AS), Diversispora spurca (DS), Funneliformis mosseae (FM) and Diversispora versiformis (DV) were selected, and inoculated into potted ornamental sunflower seedlings under greenhouse condition. Effects of AMF on growth, nutrient absorption and ion balance of ornamental sunflower were analyzed. Results showed that four different AMF could infect sunflower roots. In which, DS inoculation has the highest mycorrhizal colonization; whereas, the mycelial length of DV treatment in rhizosphere soil was significantly higher than the other three AMF treatments. Four kinds of AMF markedly decreased the fresh weight in roots and leaves, but significantly increase the fresh weight in flower discs. Furthermore, the four different AMF increased the nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) contents in roots, leaves and flower discs of sunflower in varying degrees, meanwhile reduced the N:P and N:K in root and the flower discs. In addition, the four different AMF significantly reduced the sodium ion (Na+) concentration but significantly increased K+/Na+, Ca2+/Na+ and P/Na+ in flower discs. The correlation analysis showed that there was a significant positive correlation between the mycorrhizal infection rate and the content of P or K in roots, or P, K, Ca in leaves, or N, K in flower discs in various organs of sunflower. In short, AMF could promote ornamental sunflower growth by ameliorating nutrient absorption and transport, adjusting the distribution of mineral elements in organs and the balance between ions, to enhance adaptability and ecological benefits.

Alteration in soil arsenic dynamics and toxicity to sunflower (Helianthus annuus L.) in response to phosphorus in different textured soils

Being analogue to arsenic (As), phosphorus (P) may affect As dynamics in soil and toxicity to plants depending upon many soil and plant factors. Two sets of experiments were conducted to determine the effect of P on As fractionation in soils, its accumulation by plants and subsequent impact on growth, yield and physiological characteristics of sunflower (Helianthus annuus L.). Experimental plan comprised of two As levels (60 and 120 mg As kg−1 soil), four P (0-5-10-20 g phosphate rock kg−1 soil) and three textural types (sandy, loamy and clayey) with three replications. Among different As fractions determined, labile, calcium-bound, organic matter-bound and residual As increased while iron-bound and aluminum-bound As decreased with increasing P in all the three textural types. Labile-As percentage increased in the presence of P by 16.9–48.0% at As60 while 36.0–68.1% at As120 in sandy, 19.1–64.0% at As60 while 11.5–52.3% at As120 in loamy, and 21.8–58.2% at As60 while 22.3–70.0% at As120 in clayey soil compared to respective As treatment without P. Arsenic accumulation in plant tissues at both contamination levels declined with P addition as evidenced by lower bioconcentration factor. Phosphorus mitigated the As-induced oxidative stress expressed in term of reduced hydrogen peroxide, malondialdehyde while increased glutathione, and consequently improved the achene yield. Although, P increased As solubility in soil but restricted its translocation to plant, leading to reversal of oxidative damage, and improved sunflower growth and yield in all the three soil textural types, more profound effect at highest P level and in sandy texture.

Effect of supplemental potassium and chitosan on growth and yield of sunflower (Helianthus annuus L.) under drought stress

In the present study, we evaluated the influence of potassium (K) and chitosan (Ct) on sunflower (Helianthus annus L.) under water limitations. The plants of a drought tolerant sunflower hybrid viz. Hysun-33 were grown to flowering stage under normal conditions and later subjected to drought by withholding irrigation at 50 days after sowing (DAS) for two weeks. Foliar spray of K (1%) and Ct (0.1%) were applied to both normal and water stressed plants, whereas the control plants were treated with water spray (control). The role of exogenous K and Ct application in improving drought tolerance of sunflower was determined by measuring various yield parameters. The obtained data was statistically analyzed following Fisher’s ANOVA technique and difference among the treatments was tested by Tukey test at probability level of 5%. The results showed that the plants foliar sprayed with the combined Ct and K maintained the highest chlorophyll content, thereby increasing the yield attributes under water deficit conditions. Also, a marked increment in macronutrients uptake was observed by Ct + K application in drought stressed plants. Our findings suggest that the application of Ct + K is an effective strategy to improve sunflower yield in arid areas.

Effect of supplemental potassium and chitosan on growth and yield of sunflower (Helianthus annuus L.) under drought stress

In the present study, we evaluated the influence of potassium (K) and chitosan (Ct) on sunflower (Helianthus annus L.) under water limitations. The plants of a drought tolerant sunflower hybrid viz. Hysun-33 were grown to flowering stage under normal conditions and later subjected to drought by withholding irrigation at 50 days after sowing (DAS) for two weeks. Foliar spray of K (1%) and Ct (0.1%) were applied to both normal and water stressed plants, whereas the control plants were treated with water spray (control). The role of exogenous K and Ct application in improving drought tolerance of sunflower was determined by measuring various yield parameters. The obtained data was statistically analyzed following Fisher’s ANOVA technique and difference among the treatments was tested by Tukey test at probability level of 5%. The results showed that the plants foliar sprayed with the combined Ct and K maintained the highest chlorophyll content, thereby increasing the yield attributes under water deficit conditions. Also, a marked increment in macronutrients uptake was observed by Ct + K application in drought stressed plants. Our findings suggest that the application of Ct + K is an effective strategy to improve sunflower yield in arid areas.

Effectivity of Arbuscular Mycorrhyza Fungi (AMF) and Nitrogen Fertilizer on The Growth and Yield of Sunflower (Helianthus annus L.)

One of the main products of sunflower is the seed which is a producer of vegetable oil that is needed in the pharmaceutical industry and the health sector. The price of sunflower seed oil is currently very high for the market but sunflower production in Indonesia is quite low. This potential can be used as the basis for the development of sunflower cultivation in Indonesia. One of the efforts to increase the content of sunflower seed oil is to improve proper cultivation techniques and modifications in cultivation techniques. One of the cultural techniques in increasing production is to get the right dose of nitrogen (N) fertilization. The addition of Arbuscular Mycorrhiza Fungi (AMF) is expected to increase the absorption of N nutrients in the soil, thereby increasing the growth and yield of sunflowers. This study aimed 1) effectivity of AMF and nitrogen fertilizer application with various doses on growth and yield of sunflower, 2) to obtain the right dose of N fertilizer on growth and yield of sunflower The study used a Split-plot Design with 3 replications. The first factor as the main plot is AMF i.e. F0 = without AMF, F1 = with AMF 5 g hole-1. The second factor as a sub-plot is the dose of urea fertilizer with 4 levels i.e. N1 = 50 kg N Ha-1, N2 = 100 kg N Ha-1, N3 = 150 kg N Ha-1, N4 = 200 kg N Ha-1. Observations data were evaluated by analysis of variance if the obtained F count was greater than F table 5% followed by a further test of DNMRT at the 5% significant level. Result showed 1) the effectivity of AMF and nitrogen fertilization on sunflowers was able to increase the number of leaves, accelerate the initiation of flowering, increase the diameter of sunflowers, total seeds per plant, the weight of 100 seeds, and seed production per plant, 2) Economically, the application of nitrogen fertilizer with a dose of 150 kg N Ha-1 is more appropriate in increasing the growth and production of sunflowers

Dynamic metabolic and transcriptomic profiling reveals the biosynthetic characteristics of hydroxycinnamic acid amides (HCAAs) in sunflower pollen

Sunflower pollen is a natural nutritious food with a long history and multiple functions, however, the main chemical components apart from flavonoids and their biosynthesis processes have not been thoroughly investigated. In this study, seven hydroxycinnamic acid amides (HCAAs) (1–7) abundant in sunflower pollen were isolated and identified as one type of the pollen’s main chemicals. For a comprehensive understanding of HCAA biosynthesis in Helianthus annuus flowers, RNA-seq, metabolomics, and key genes related to biosynthesis in the sunflower were studied. A large number of compounds at different sunflower growth stages (the 7th, 14th, 21st, and 28th days) and high expression levels of related genes in the transcriptome were detected. A molecular network was constructed to clarify the synthetic pathway of HCAAs, which revealed high transcriptional levels of spermidine hydroxycinnamoyl transferase genes (HaSHT2795 and HaSHT2436) in 14–21-days-old flowers. HaSHT2795 enzymes catalyze tri-coumaroylspermidine formation, and virus-induced gene silencing to inhibit HaSHT2795 and HaSHT2436 could significantly reduce the synthesis of hydroxycinnamic acid amides in sunflower pollen. HCAAs were inferred to be related to the formation of pollen walls and the health effects of pollen. Analyzing HCAA biosynthesis and accumulation in H. annuus pollen will be helpful to understand the functions of HCAAs in the development of pollen and its nutritional value.

Effect of Sulphur Levels on Growth, Yield Parameters, Yield, Nutrient Uptake, Quality and Economics of Sunflower: A Review

Sunflower is an important crop cultivated all over world owing to its versatile nature of adaptation to different agro-climatic and soil conditions. In India sunflower gains momentum as an edible oil and ranks fourth substantially by reducing the shortage of vegetable oil. Nutritionally sunflower oil benefits human due to presence of high linoleic acid content and absence of linolenic acid content. The productivity is lower due to different factors among which nutrient management especially sulphur that plays pivot role in governing the growth, yield and quality of sunflower. Sulphur contains aminoacids viz., cystein, methionine, cystine, vitamins B, biotin and thiamine. The protolytic enzymes aids in improving the oil content, protein content and quality of seeds by sulphur supplement. Extensive investigations of research scientist on sulphur levels were critically reviewed. Application of sulphur at 40 to 60 kg ha-1 was found to increase the growth and yield attributes, yield, quality as well as higher benefit cost ratio sustaining the livelihood of sunflower growers.

DESENVOLVIMENTO DO GIRASSOL SOB DOSES DE BIOFERTILIZANTE BOVINO EM CULTIVO AGROECOLÓGICO

Sunflower production in the Northeast is still incipient. It would be an important challenge for Piaui to produce sunflower, in quantity and quality, as it would certainly add to the State's agricultural GDP, especially with regard to the production of edible oil, extracted from achenes. The effects of a liquid bovine biofertilizer on sunflower growth and biomass under agroecological cultivation were analyzed. The experiment was carried out in DIC, with five treatments and six repetitions, totaling 30 experimental units. The four treatments with the biofertilizer were 50, 75, 100 and 125% of the optimal recommendation, and the control (without application). It was analyzed: plant height (AP), stem diameter (DC), chapter diameter (DCAP), shoot dry matter production (MSPA) and root system (MSSR). The results were subjected to analysis of variance and later regressions were performed. Despite the non-significant results, the sunflower plants that received the biofertilizer showed better performance when compared to plants that did not receive the liquid organic input; furthermore, in the variables AP and MSSR, the best results were found in plants that received the highest concentrations of biofertilizer. As for the other variables, the maximum points (concentration of biofertilizer) were between 79 and 167%, with a suggestion of toxic effect in more concentrated doses of the organic input.

Sulfur Application Combined with Planomicrobium sp. Strain MSSA-10 and Farmyard Manure Biochar Helps in the Management of Charcoal Rot Disease in Sunflower (Helianthus annuus L.)

Sunflower (Helianthus annuus L.), a member of the Asteraceae, is one of the major oilseed crops around the world. Charcoal rot caused by Macrophomina phaseolina (Tassi) Goid is the most damaging disease of sunflowers globally. Fungicides are mostly used to control charcoal rot; however, these cause environmental pollution and pose adverse effects on the ecosystem. Therefore, ecofriendly management options are inevitable for the management of charcoal rot disease. Plant mineral nutrition, the use of plant growth-promoting rhizobacteria and biochar have recently been manipulated for the management of different plant diseases. However, the interactive effects of all these treatments have rarely been tested on charcoal rot suppression in sunflowers. This study assessed the influence of sulfur (0 and 2.25 mg/kg) combined with farmyard manure biochar (2%), NPK (20:20:20 mg/kg) and three different plant growth-promoting rhizobacteria (PGPR) strains on the charcoal rot suppression growth, yield, biochemistry and physiology of sunflower. The PGPR strains included in the study were Bacillus sp. strain MR-1/2 (regarded as PGPR1), Achromobacter sp. strain FB-14 (regarded as PGPR2) and Planomicrobium sp. strain MSSA-10 (regarded as PGPR3). The charcoal rot infestation was induced by inoculating the soil with M. phaseolina, and the impacts of the different treatments were studied on the disease infestation, growth, yield, biochemistry and physiology of sunflowers under 0 and 2.25-mg/kg S application. The results revealed that farmyard manure biochar and Planomicrobium sp. strain MSSA-10 in combination with 2.25-mg/kg S proved effective for the management of charcoal rot disease through regulating the antioxidant enzymes’ activities and strengthening the immune system of sunflower plants. The studied health markers (total chlorophyll content and carotenoids) and stress markers (total protein content, catalase and peroxidase) were significantly altered by the applied treatments under 0 and 2.25-mg/kg S applications. The findings of the experiment indicated that both farmyard manure biochar and Planomicrobium sp. strain MSSA-10, combined with 2.25-mg/kg S, could be used to enhance the crop yield and manage charcoal rot disease in sunflowers. Farmyard manure biochar and Planomicrobium sp. strain MSSA-10 are an easy-to-apply, cost-effective, ecofriendly and sustainable option for the management of charcoal rot disease in sunflowers.

Effect of deficit irrigation on yield and water productivity of sunflower in East and South-eastern coastal plains of Odisha

Aim: To study the effect of deficit irrigation on yield and water productivity of sunflower in East and South eastern coastal plains of Odisha. Methodology: The present study on water productivity was undertaken using hybrid sunflower (Swathi: NSFH-145) with application of deficit irrigation having Management Allowable Deficit level of 20%, 40%, 60% and one farmers’ practice of 70% MAD level of irrigation. Growth attributes like leaf area Index, plant height, and head diameter were recorded at 20, 45, 65 and 80 days after sowing. Yield attributes like 1000 seed weight (test weight), above ground biomass and grain yield, were recorded after threshing. Results: The growth, yield and water productivity of sunflower were significantly influenced by different irrigation levels. Irrigation scheduling at 20% MAD level showed the highest grain yield, while the lowest yield was obtained from the farmers’ practice. Irrigation at 60% MAD level showed the highest water productivity when compared with farmer’s practice as it produced the highest yield per unit quantity of water application of 0.85 kg m-3 and also produced the highest average benefit to cost ratio of 2.08. Interpretation: Taking the yield, water productivity and benefit-cost ratio into account, irrigation at 60% MAD level was found to be the best. However, irrigation at 50% to 60% MAD level may be suggested for growing sunflower under water scarce conditions in sandy loam soil for increasing water productivity.

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.

Effect of different soil moisture regimes on plant growth and water use efficiency of Sunflower: experimental study and modeling

BackgroundClimate change and increasing demand in non-agricultural sectors profoundly affect the availability and quality of water resources for irrigated agriculture. The FAO AquaCrop simulation model provides a sound theoretical framework to investigate crop yield response to environmental stress. This model has successfully simulated crop growth and yield as influenced by varying soil moisture environments for crops. Integrating crop models that simulate the effects of water on crop yield with targeted experimentation can facilitate the development of irrigation strategies for high yield procurement and improving farm level water management and water use efficiency (WUE) under climatic condition of District Hyderabad, Sindh, Pakistan.ResultsThis study was based on completely randomized block design with three treatments including T1 (30% soil moisture depletion), T2 (50% soil moisture depletion) and T3 (70% soil moisture depletion) with three replicates. In order to determine the crop water requirements under desired treatments, the gypsum blocks were used for computing the daily soil moisture depletion. The result shows that total volume of water applied to crop under T1, T2 and T3 was 9689, 5200 and 2045 m3 ha−1, respectively. As a result, the grain yield under T1, T2 and T3 was 13.2, 12.1 and 14.3 t ha−1, respectively. These results advocate that total yield of crop under T1 and T2 was less as compared to T3. The T3 gave higher yield and WUE compared than other treatments. On the other hand, results revealed that the simulated sunflower yields showed a good agreement with their measured under T3. The simulated grain yield was 15.5 t ha−1, while the measured yield varied from 12.1 to 14.3 t ha−1. This study suggested that WUE under T3 was more as compared to T1 and T2. The results showed that the T3 gave the highest crop yield in relation to WUE and optimize yield of sunflower crop under water scarcity.ConclusionThe Aquacrop model could very well predict crop yield and WUE at T3 under experiential region for sunflower production.