GA3 Sprays Research Articles

Effect of Hormones on Yield and Economics of Mustard (Brassica juncea L.) under Southern Telangana Agro-Climatic Conditions

An experiment was carried out at student farm, College of Agriculture, Rajendranagar, Hyderabad, Telangana, in sandy loam soils during rabi 2020 to study the effect of hormones on growth and yield of mustard under Southern Telangana Agro-climatic conditions. The experiment was laid out in randomized block design with ten treatments. The treatments comprised were: T1-Control (RDF 60:40:40 N, P2O5, K2O kg ha-1), T2 (RDF + foliar spray of GA3 @ 45 ppm at flowering), T3 (RDF + foliar spray of GA3 @ 45 ppm at pod development), T4 (RDF + foliar spray of GA3 @ 45 ppm at flowering and pod development), T5 (RDF + foliar spray of humic acid @ 1.5% at flowering), T6 (RDF + foliar spray of humic acid @ 1.5% at pod development), T7 (RDF + foliar spray of humic acid @ 1.5% at flowering and pod development), T8 (RDF + foliar spray of GA3 @ 45 ppm fb humic acid @ 1.5% with 2 days interval at flowering), T9 (RDF + foliar spray of GA3 @ 45 ppm fb humic acid @ 1.5% with 2 days interval at pod development) and T10 (RDF + foliar spray of GA3 @ 45 ppm fb humic acid @ 1.5% with 2 days interval at flowering and pod development). Results indicated that, application of RDF + foliar spray of GA3 @ 45 ppm fb humic acid @ 1.5% with 2 days interval at flowering and pod development (T10) and application only at flowering (T8) gave the similar and higher yields and economic returns. As the cost of cultivation of T10 was higher than T8, BC ratio was higher for T8.

Understanding the Role of Gibberellic Acid and Paclobutrazol in Terminal Heat Stress Tolerance in Wheat.

Understanding the physiological mechanism of tolerance under stress conditions is an imperative aspect of the crop improvement programme. The role of plant hormones is well-established in abiotic stress tolerance. However, the information on the role of gibberellic acid (GA) in abiotic stress tolerance in late sown wheat is still not thoroughly explored. Thus, we aimed to investigate the role of endogenous GA3 level in stress tolerance in contrasting wheat cultivars, viz., temperature-tolerant (HD 2643 and DBW 14) and susceptible (HD 2189 and HD 2833) cultivars under timely and late sown conditions. We created the variation in endogenous GA3 level by exogenous spray of GA3 and its biosynthesis inhibitor paclobutrazol (PBZ). Tolerant genotypes had higher antioxidant enzyme activity, membrane stability, and photosynthesis rate, lower lipid peroxidase activity, and better growth and yield traits under late sown conditions attributed to H2O2 content. Application of PBZ escalated antioxidant enzymes activity and photosynthesis rate, and reduced the lipid peroxidation and ion leakage in stress, leading to improved thermotolerance. GA3 had a non-significant effect on antioxidant enzyme activity, lipid peroxidation, and membrane stability. However, GA3 application increased the test weight in HD 2643 and HD 2833 under timely and late sown conditions. GA3 upregulated GA biosynthesis and degradation pathway genes, and PBZ downregulated kaurene oxidase and GA2ox gene expression. GA3 also upregulated the expression of the cell expansins gene under both timely and late sown conditions. Exogenous GA3 did not increase thermotolerance but positively affected test weight and cell expansins gene expression. No direct relationship existed between endogenous GA3 content and stress tolerance traits, indicating that PBZ could have conferred thermotolerance through an alternative mechanism instead of inhibiting GA3biosynthesis.

RESPONSE OF PLANT GROWTH REGULATORS ON THE GROWTH, FLOWERING AND YIELD ATTRIBUTES OF AFRICAN MARIGOLD (TAGETES ERECTA. L)

Tagetes is a genus of annual, perennial or herbaceous plant in the family Asteraceae. Most of the species have pinnate green leaves. Blooms are naturally occurring in golden, orangeyellow, and white colour, often with maroon highlights. Floral heads are 4 to 6 cm in diameter, generally with both ray florets and disc florets. The present study was conducted at the post graduate research laboratory at Department of Horticulture, Faculty of Agriculture, Annamalai University to find out the “Effect of plant growth regulators on flowering and yield of African marigold (Tagetes erecta Linn)”. The experiment was laid out in Randomized Block Design with three replications. There were ten treatments, viz., GA3 100 ppm, GA3 200 ppm and GA3 300 ppm, NAA 100 ppm, NAA 200 ppm, NAA 300 ppm, Ethrel 50 ppm, Ethrel 100 ppm, and Ethrel 150 ppm and control. Among the growth regulators tried, GA3 200 ppm as foliar application on 30 and 60 days after transplanting registered the highest values for plant characters like plant height (47.1 cm), number of branches ( 35.1), days taken to first flower bud appearance (39.3 days), days taken to flower opening (37.6 days), longevity of flower (11.17 days), stalk length (12.1 cm), diameter of flower (7.8 cm), number of flowers per plant (40.3), weight of the single flower (9.1 g), yield of flowers per plant (337 g) and flower yield per plot (11.1 kg). From the present study, it is recommended that spraying of GA3 200 ppm on 30 and 60 days after transplanting improved yield and quality of African marigold flowers.

Cadmium Phytoextraction Potential of Ricinus communis Significantly Increased with Exogenous Application of Growth Regulators and Macronutrients

ABSTRACT Phytoremediation has emerged as promising technology for reclamation of metal-polluted sites. The present study was conducted with an aim to assess the hyperaccumulation potential of Ricinus communis for cadmium, with the application of exogenous substances, [nitrogen (N), phosphorus (P) and potassium (K)] and phytohormones [Gibberellic acid (GA3) and Indole acetic acid (IAA)]. These were applied to increase plant biomass, improve phytoextraction of Cd and its accumulation in aerial parts, with generation of endogenous proline and phenols in R. communis, grown in soil contaminated with 100 mg Cd/Kg. Plant hormones were used only as foliar spray while growth regulators were applied to soil and also used as foliar spray. T4 (Cd+NPK AS) significantly increased root length, T12 (GA3+ NPK FS) highly increased stem length and leaf length as compared to control C1 (plant only Cd). FBM was highly increased by N alone or in combination with P, K, and GA3 foliar sprayed in R. communis. Conclusively, it was found that NPK (foliar) in combination with GA3 followed by N and IAA, significantly increased biomass, Cd concentration and accumulation in all the treated plants of R. communis. Cadmium bio-concentration values for R. communis were higher than unity (1) i.e. ± 2.54. Highest significant concentration of phenolic and proline in R. communis were recorded in combination treatments of GA3 and NPK foliar spray while in other plants in NPK addition into soil treatment. Thus, R. communis has the natural potential as hyperaccumulator and further study is required for its industrial implementation in polluted soil.

Improved of growth and phytostabilization potential of lead (Pb) in Glebionis coronaria L. under the effect of IAA and GA3 alone and in combination with EDTA by altering biochemical attributes of stressed plants

This study evaluated the effect of EDTA, IAA and GA3 alone and in combination in improving plant growth, Pb accumulation, and management of effective mechanisms associated with alleviation of Pb-induced adverse effect in Glebionis coronaria L. grown on industrial area in Alexandria. In this regards, 10-week-old plants were subjected to IAA and GA3 as a foliar spray and EDTA was supplied in two doses 50 and 200mgkg−1 soil. EDTA significantly reduced the plant growth and dry biomass, whereas GA3 and IAA foliar spray increased growth significantly when compared with control (uncontaminated soil). In combined treatments of EDTA + GA3 +IAA, the biomass was restored, which shows that GA3 and IAA did compensate the negative effect of EDTA on plant growth and increased the Pb uptake significantly into roots. There were high GSH contents parallel with the increase of glutathione-S-transferase activity and induction of the antioxidant enzymes (SOD, CAT, APX, GR) as well as oxidized glutathione and ascorbic acid contents in leaves and roots when compared to control plants. This study suggests that G. coronaria is promising species for decontamination of Pb -contaminated soil and the application of EDTA together with IAA and GA3 could be a useful strategy for enhancing the phytostabilization capability of Glebionis coronaria L. to eliminate Pb from contaminated soils. Novelty statement: The objective of this paper is to investigate the physiological performance of Glebionis coronaria as a new native for phytoremediation by phytostabilization mechanism of Pb after treatment with EDTA and phytohormones. Chemical additives of EDTA and GA3 as well as IAA are promising alternatives to provide added benefits due to their individual credentials in improving the overall phytostabilization effectiveness and better immobilization efficiency in treating Pb contaminated soils by altering biochemical attributes of stressed plants. Currently these additives are not employed widely in large-scale field implementations, so field applications of these additives using Glebionis coronaria are essential for Phytoremediation of Pb-contaminated soils.

Productivity and Fruit Quality of Lime (Citrus aurantifolia L.) as Affected by GA3 and NAA Foliar Spray

A field trial was achieved during 2018 and 2019 seasons on 9-years old Balady lime trees, to study the effect of spraying gibberellic acid (GA3) and naphthalene acetic acid (NAA) at 10, 20 and 30 ppm three times each year on yield and fruit physical and chemical properties of the fruit, grown in sandy reclamation soil located at Cairo-Alexandria desert road (60 Km from Cairo city), Egypt. A gradual yield increment was observed, physical and chemical properties of Balady lime fruits were improved the two growth regulators concentration from 0.0 to 30 ppm. Meaningless stimulation was detected among the two higher concentrations of GA3 and NAA namely 20 and 30 ppm. The best results with regard to yield, fruit physical and chemical properties of Balady lime obtained when the trees were sprayed with GA3 combined with NAA each at 20 ppm.

Exogenous Gibberellic Acid and Cytokinin Effects on Budbreak, Flowering, and Yield of Blackberry Grown under Subtropical Climatic Conditions

In subtropical climates, inadequate winter chill limits blackberry (Rubus L. subgenus Rubus Watson) production by causing poor and erratic floral budbreak. To compensate for a lack of chilling, bud dormancy-breaking agents must be developed for subtropical blackberry production. Our previous study showed that gibberellic acid (GA3) promotes budbreak in three blackberry cultivars but has potential negative side effects on floral development in ‘Natchez’. 6-benzyladenine (6-BA) is a synthetic cytokinin that can act as an antagonist of gibberellins during floral transition. The objectives of this study were to evaluate cultivar × exogenous GA3 interactions, characterize dose effects of exogenous GA3, and examine synergistic effects of GA3 and 6-BA. Three field experiments were conducted in west central Florida. All spray treatments were applied at the end of the chilling period. In the first experiment, ‘Natchez’, ‘Navaho’, and ‘Ouachita’ were treated with GA3 at 0 or 99 g·ha−1. Budbreak was promoted by exogenous GA3 in all three cultivars (0.9% to 4.5% vs. 42.9% to 69.4%), but yield responses varied considerably. Exogenous GA3 increased the yield of ‘Navaho’ and ‘Ouachita’ by 560% to 931%, whereas it induced flower abortion and caused a 15% yield reduction in ‘Natchez’. In the second experiment, ‘Natchez’ was treated with GA3 at 0, 25, 99, or 198 g·ha−1. Budbreak increased linearly with GA3, but yield decreased exponentially with GA3 because of dose-dependent flower abortion. In the third experiment, ‘Natchez’ was subjected to five treatments: 1) water control; 2) GA3 spray application; 3) 6-BA spray application; 4) combined spray application of GA3 and 6-BA; and 5) sequential spray application of 6-BA at 9 days after GA3 application. Application rates were 99 and 47 g·ha−1 for GA3 and 6-BA, respectively. Exogenous 6-BA suppressed GA3-induced flower abortion only to a limited extent. As a result, GA3-containing treatments caused 65% to 83% yield reductions compared with the control (2382 vs. 410–823 g/plant). These results demonstrate that GA3 is a highly effective bud dormancy-breaking agent for blackberry. However, the drawback of GA3 is cultivar-dependent flower abortion, which cannot be fully mitigated by 6-BA. The use of GA3 can be an important management practice for subtropical blackberry production, but its practical implementation must consider cultivar-dependent responses.

Effect of pre-harvest application of GA3, Naphthalene acetic acid and borax on fruit drop, yield and quality of Mango cv. Amrapali

To investigate the effect of pre-harvest application of GA3, Naphthalene acetic acid and borax on fruit drop, yield and quality of Mango cv. Amrapali, an experiment was carried out in the Garden, Department of Horticulture, C. S. Azad University of Agriculture and Technology, Kanpur (U.P.) during the cropping season 2018-2019. The experiment was laid out in Randomized Block Design (RBD) with three replication and ten treatments viz., GA3 @ 25 ppm (T1), GA3 @ 50 ppm (T2), GA3 @ 75 ppm (T3), NAA @ 20 ppm (T4), NAA @ 40 ppm (T5), NAA @ 40 ppm (T6), NAA @ 60 ppm (T7), borax @ 0.2% (T8), borax @ 0.4% (T9) including a control or water spray (T10). Spraying of plant growth regulators and micronutrient was done at pea stage of fruits set on 2st March, 2019.From the results obtained during present experimentation, it is reported that pre-harvest spraying of GA3 at 25 ppm results significant decrease in fruit drop (85.77%) with increase in fruit retention (14.23 %) and number of fruits per panicle (6.43). Plants sprayed with the GA3 at 50 ppm results significantly more fruit yield (50.67 kg/tree) of fruits having more polar (9.11 cm) and equatorial diameter (7.39 cm), more pulp (74.56%), pulp: stone ratio (7.12) with decrease in peel (14.94%) and stone per cent (10.51%). Increased fruit weight (244.59 g), volume (255.43 cc), specific gravity (1.09 g/cc), total soluble solids (18.36 0Brix), total sugars (17.75%), ascorbic acid (37.60 mg/100g) were also found with the pre-harvest spraying of GA3 at 75 ppm, whereas titratable acidity (0.50%) contents in the fruits ware drastically reduced under this treatment.

Effect of plant growth regulators on growth, yield and yield attributing characters of okra (Abelmoschus esculentus L.)

The field experiment was conducted at the research farm, J.N.K.V.V., College of Agriculture, Tikamgarh (M.P.), India; during kharif season of 2016-2017 to study the Effect of plant growth regulators on growth, yield and quality of Okra (Abelmoschus esculentus L.) cv. VRO-6. The experiment was laid out in Randomized Block Design with three replication accommodating ten treatments in each replication. The treatments consists of GA3 (25, 50 and 100 ppm), NAA (100, 150 and 200 ppm), Cycocel (250, 500 and 750 ppm) and Control. The result revealed that foliar spray of GA3 was found beneficial for increasing maximum plant height (96.17 cm), maximum number of leaves (23.79) and minimum number of days to 50% of flowering (36.25 days) while the maximum numbers of branches (5.77) were recorded in cycocel 750 ppm. The highest number of fruit (22.05), highest fruit yield plant-1 (301.19 g) and fruit yield ha-1 (167.38 q) was recorded with GA3 100 ppm in comparison to the rest of the treatments. Therefore, it can be concluded that the treatment GA3 is the best treatment to enhancing okra productivity.

Effects of gibberellic acid (GA3 ) application before anthesis on rachis elongation and berry quality and aroma and flavour compounds in Vitis vinifera L. 'Cabernet Franc' and 'Cabernet Sauvignon' grapes.

Gibberellic acid (GA3 ), a plant-growth regulator, is often used to obtain enlarged table grape berries and induce seedlessness in them. However, the effects of GA3 on rachis elongation and bunch compactness have seldom been reported in wine-grape production. We assessed the effects of GA3 spraying on wine-grape inflorescences and bunches and their practical implications for viticulture in the Jiaodong Peninsula, China. Various GA3 concentrations were sprayed on field-grown Vitis vinifera L. 'Cabernet Franc' (CF) and 'Cabernet Sauvignon' (CS) grapevines before anthesis in the Jiaodong Peninsula, China, in 2015 and 2016. Inflorescence length during berry development was measured, and flavonoids and aroma compounds in the fruit were detected by high-performance liquid chromatography - mass spectrometry (HPLC-MS) and gas chromatography - mass spectrometry (GC-MS), respectively. For both cultivars, 50 and 100 mg L-1 GA3 caused significant elongation of the rachis, whereas there was no significant effect on inflorescence growth and berry seed number. Anthocyanin, flavonol, and flavan-3-ol levels in mature berries were not significantly influenced by GA3 spraying, whereas C13 -norisoprenoids were modified. The application of 50-100 mg L-1 GA3 prior to grapevine anthesis caused elongation of inflorescences and bunches, and eased cluster compactness in CF and CS, and no negative effects were observed on the yield and seed numbers. The concentration and composition of flavonoids and most aroma compounds were not influenced, except that the norisoprenoids were increased by 50 mg L-1 GA3 applications. © 2020 Society of Chemical Industry.

Effect of Different Ratios Nano-Fertilizer and Gibberellic Acid on the Vegetative Growth and Chemical Compositions of Codiaeum Variegatum (L.) cv. Gold Dust

A pot experiment was conducted in greenhouse and nursery at Ornamental Farm Faculty of Agriculture, Suez Canal University, Ismailia Governorate Egypt, during the two seasons of 2018 and 2019. The aim of this work is to study the effect of different treatments of Hyper feed Nano-fertilizer NPK (19:19:19) Nano-fertilizer rates (0, 1.5, 3.0, 4.5 g/L) added every 15 days with irrigation water drench on the pot with 400 m/L and monthly foliar application with Gibberellic acid (GA3) at (0, 100, 200 and 300 ppm) either alone or in combination from the 1st of May to the 1st of October on the vegetative growth and some chemical constituents of Codiaeum variegatum (L.) cv. Gold dust plants. The results showed that Nano-fertilizer plus GA3 was the most effective compound to improving all growth parameters of Codiaeum plants, followed by Nano-fertilizer, while GA3 was the second in order. Among Nano-fertilizer treatments, the highest level of Nano-fertilizer at 4.5 g/L was optimum for growth of Codiaeum plants. Nano-fertilization every 15 days with Hyper feed Nano-fertilizer NPK (19:19:19) at 4.5 g/l combined with foliar spray of both GA3 at 300 ppm resulted in the highest significant values for plant height, stem diameter, number of leaves/plant, leaf area and fresh and dry weights of plant, fresh and dry weights of leaves, stems and roots/plant. Data also showed that the previously mentioned combination resulted in the highest contents of N, P, K, Total carbohydrates, and Total chlorophyll in Codiaeum leaves.

Effect of spraying of GA3 and Some Micronutrients on the growth and Mineral content of Cress plant (Lepidium sativum L.)

This study is conducted in aspicial farm in Adujail city\Salahaddin Governorate at the season 2015 on the cress plant. Afactorial experiment has conducted with two factors, the first is spraying with GA3 (G0 without spraying, G1 spraying with 50 mg.L-1, G2 spraying with 100 mg.L-1of GA3).the second factor is spraying with Micro Nutrients (T0 without spraying, T1spraying with 50 mg.L-1 of Fe,T2 spraying with 50 mg.L-1 of Mn, T3 spraying with amixture of 50+50 mg.L-1from Fe and Mn). The experiment is designed with (RCBD), the treatments were replicated 4 times and Duncuns Multiple Range Test at the probability 5% is used and the results are as fellowed:
 GA3 spraying causes asignificant increase in all Vegetative growth characters compared with the others which are not sprayed and also the Macro Nutrients concentration. Micro Nutrients sprayes on the Cress plants also causes asignificant increase in most Vegetative characters and Macro and Micro Nutrients content, specially the treatment of Fe and Mn mixture. Interaction between GA3 and Micronutrient is significant in all the treatment specially the treatment (100 mg.L-1 of GA3 + amixture of 50+50 mg.L-1 of Fe + Mn ) which give ahighest values of Vegetative growth and Macro and Micro Nutrients content .

Climate conditions and spray treatments induce shifts in health promoting compounds in cherry (Prunus avium L.) fruits

Effects of repeated sprayings expected to affect phenolic, anthocyanin, carotenoid and ascorbic acid content in ‘Skeena’ and ‘Sweetheart’ cherries were observed during two years (without addition of calcium (Ca) in 2015, and with Ca in 2016). A shift in phytonutrients, with higher phenolic and carotenoid- and lower ascorbic acid content was observed when comparing Ca and the control (water) treatments in 2016 compared to 2015. Higher radiation, higher temperatures and less precipitation in 2015 compared to 2016 likely contributed to this shift.Gibberellic acid (GA3), abscisic acid (ABA), salicylic acid (SA) and glycine betaine (GB) sprays increased anthocyanin content in 2015 and for ‘Skeena’ cherries in 2016. GA3 and GB induced lower carotenoid content for ‘Skeena’- in 2015 and for ‘Sweetheart’ cherries in 2016 and lowered ascorbic acid content for ‘Sweetheart’ cherries. GA3 sprays induced the largest changes, increasing anthocyanin- (42 %), lowering carotenoid (19 %) and ascorbic acid content (53 %) compared to control. Ascophyllum nodosum, one of the novel spray treatments next to GB, appears to induce an effect opposite to GB, increasing carotenoid and ascorbic acid, but lowering phenolic content. Whether these phytonutrient shifts, due to climate conditions or to spray treatments, are beneficial to consumer health is unclear.

Effects of Gibberellic Acid Application after Anthesis on Seed Vigor of Indica Hybrid Rice (Oryza sativa L.)

Gibberellic acid (GA3) application after anthesis is an important practice in hybrid rice seed production, and it plays diverse roles in seed quality and seed yield. The main objective of this study was to determine (1) the effects of GA3 application after anthesis on seed vigor and (2) the optimal GA3 dosage applied to Indica hybrid rice seed production. Field experiments of different GA3 dosages (15 g hm−2 and 30 g hm−2, respectively) after anthesis were conducted in 2016 and 2017, and seed vigor parameters, stigma vigor index, and seed yield were determined. We found that significant differences in seed vigor parameters by a standard germination test and a cool germination test were observed among different GA3 dosages after anthesis. Compared with the water spraying treatment, the germination percentage (GP) increased by 2.5–6.3%, and the vigor index (VI) increased by 8.9–19.8% from GA3 application after anthesis, respectively. Moreover, the stigma vigor index of the female parent was enhanced with an increasing GA3 dosage, and there were significant increases (7.5–16.0%) between the water spraying treatment and GA3 spraying treatments. There were positive significant relationships between the VI and stigma vigor index. Additionally, the seed yield of the GA3 application with 30 g hm−2 was 3.9% higher on average than that of the water spraying treatment. Therefore, our study suggests that seed vigor can be increased by GA3 application after anthesis, and GA3 application should be applied at a rate of 30 g hm−2 to improve seed vigor and maintain seed yield in Indica hybrid rice seed production.

Male flower induction significantly affects androgenesis in cucumber (Cucumis sativus L.)

ABSTRACTMale flower induction and androgenesis in three genotypes of cucumber (Cucumis sativus), two Beth alpha F1 hybrids (BT1 and BT2, gynoecious) and Dastgerdi (DTG, monoecious), were evaluated. Induction of male flowers in gynoecious cucumber cultivars was assessed by single and combinatorial spraying of AgNO3 (3 mM), GA3 (1.5 mM) and CoCl2 (3 mM) after the first true leaf emergence. After 6 weeks from the beginning of treatments, the average numbers of male flowers induced by spraying AgNO3, GA3, and CoCl2 were 42, 14.5, and 0, respectively. Androgenesis was performed in two gynoecious cultivars, in which the donor plants were treated with AgNO3 (3 mM) or GA3 (1.5 mM) and the DTG cultivar without treatment. Among the three cultivars, the DTG showed the highest percentage of embryogenic calli formation (62.2%) and number of embryos per anther (1.81). In the gynoecious cultivars, the percentage of embryogenic calli formation (27.1%) and number of embryos per anther (0.23) in the anthers of GA3 treated plants were significantly higher than those treated by AgNO3. Cytological and SSR marker analysis of regenerants showed that 16 plants were spontaneous doubled haploid, 2 plants were diploid and one plant was tetraploid.

Effect of GA3 and NAA on growth and yield of cabbage

A field experiment was conducted at the Plant Physiology Field of Horticulture Research Center (HRC), Bangladesh Agricultural Research Institute, Gazipur during the rabi seasons of 2015-16 and 2016-17 to study the response of cabbage (var. Krishibid Hybrid-1 and Atlas-70) to foliar application of GA3 and NAA with different concentrations. The experiment was laid out in a Randomized Complete block Design with three replications. The experiment consisted of eight treatments viz., three levels of GA3 (at 50, 75 and 100 ppm) and four levels of NAA (at 40, 60, 80 and 100 ppm) along with distilled water as control. The varieties Krishibid Hybrid-1 and Atlas-70 were used in 2015-16 and 2016-17, respectively. Foliar spray of GA3 and NAA was given at 25 and 45 days after transplanting of seedling. The results of the investigation indicated significant differences among the treatments on most of the parameters studied. In Krishibid Hybrid-1, application of 50 ppm GA3 and 60 ppm NAA increased plant height, plant spread, number of leaves, chlorophyll content, head height, head diameter, single head weight without unfolded leaves as well as head yield (81.18 t/ha for 50 ppm GA3 and 78.57 t/ha for 60 ppm NAA) than the control (67.29 t/ha) and other treatments. But, in Atlas-70, application of 75 ppm GA3 gave the maximum values of most of the growth parameters, yield components and yield (102.40 t/ha), which was followed by 50 ppm GA3 (94.96 t/ha). In Krishibid Hybrid-1, application of 60 ppm NAA gave the highest benefit-cost ratio (BCR) of 3.63 followed by 75 ppm GA3 (3.59) while in Atlas-70, 75 ppm GA3 recorded the highest BCR of 4.79 followed by 50 ppm GA3 (4.54) and 60 ppm NAA (4.37). Therefore, application of GA3 @ 50-75 ppm or NAA @ 60 ppm concentration can be recommended for increasing the yield of cabbage with higher return.
 Bangladesh J. Agril. Res. 44(2): 367-376, June 2019

Effect of foliar spray of GA3 and NAA on sex expression and yield of bitter gourd

A field experiment was conducted at the Plant Physiology field of Horticulture Research Center, BARI, Gazipur during two consecutive years of kharif 2014 and 2015 to assess the effect of GA3 and NAA on sex expression, yield and yield components of bitter gourd (Momordica charantia L.) var. BARI Karola-1. Eeleven treatments comprising five concentrations each of gibberellic acid (50, 100, 150, 200 and 300 ppm) and naphthalene acidic acid (50, 100, 150, 200 and 300 ppm) along with distilled water considered as control were evaluated in randomized complete block design with three replications. Gibberellic acid (GA3) and Naphthalene acidic acid (NAA) were sprayed at 4 leaf stage; second spray was done at 35-38 DAS and third spray done at flowering stage. All the treatments improved the flowering and yield characters over control. Foliar spray of NAA @ 150 ppm and 200 ppm was found better in terms of sex expression, yield and yield attributes of bitter gourd as compared to control and other treatments. Spray of NAA @ 150 ppm gave the lowest number of male flowers and the highest number of female flowers thereby produced the lowest sex ratio (male:female). Number of fruits/plant, individual fruit weight and fruit yield/plant were also found maximum from NAA 150 ppm. Maximum fruit yield was recorded with the application of NAA @ 150 ppm. Spraying of NAA @ 150 ppm gave the maximum gross return and net return with the highest BCR of 3.17.
 Bangladesh J. Agril. Res. 44(2): 281-290, June 2019

Positive effects of foliar application of Ca, B and GA3 on the qualitative and quantitative traits of pomegranate (Punica granatum L.) cv. ‘Malase-Torshe-Saveh’

Fruit cracking and sunburn are two main disorders that adversely affect pomegranate production in Iran. Proper horticultural practices during growing season can highly affect the fruit quality. In the present study, an experiment was conducted to assess the individual and combined effects of Calcium (Ca) (0, 0.75% and 1.5%), Boron (B) (0 and 3000 ppm) and gibberellic acid (GA3) (0, 75 and 150 ppm) spraying on the fruit of pomegranate cv. ‘Malase-Torshe-Saveh’. The treatments were repeated three times during growing season. A factorial experiment was conducted based on the completely randomized block design with 18 treatments and 3 replicates and data was analyzed with SAS and JMP software. Results indicate that most of the qualitative and quantitative traits were affected by foliar spraying of these substances. The control plants resulted in the inferior fruits attributes and the highest fruit cracking and sunburn was recorded from untreated plants. Although all of the individual treatments, increased physical attributes of pomegranate fruit, however, GA3 was the most effective and resulted in the highest fruit length and diameter, fruit and 100 arils weight as well as tree yield. We observed that B application not only improved different fruit qualitative traits including size, weight and yield, but also reduced fruit cracking mainly through improving water content of fruit peel. Ca treatment was the most effective for improving fruit qualitative characteristics including TSS and reducing the cracking disorder. Altogether, our results indicated that combinatorial spraying of Ca, B and GA3 is more efficient than their individual treatment and resulted in the highest fruit yield and quality as well as the lowest cracking and sunburn disorders, which propose there are synergistic effects between these compounds. Therefore, simultaneous spraying of these three substances is suggested in orchard management for improvement the qualitative and quantitative characteristics of pomegranate cv. ‘Malase-Torshe-Saveh’.

Cooperative effects of pre-harvest calcium and gibberellic acid on tissue calcium content, quality attributes, and in relation to postharvest disorders of late-maturing sweet cherry

Six Ca(NO3)2 sprays at 0.3% and 0.6% from pit hardening (PH) to 1 week before harvest (1WBH) most effectively increased Ca uptake in sweet cherry (Prunus avium). Low concentration (<0.3%) did not affect the absorption of Ca; high concentration (> 1.6%) caused burning of leaf margins. Fruit treated with Ca had greater fruit firmness (FF), soluble solids content (SSC) and titratable acidity (TA) and fewer disorders than untreated fruit while retaining marketable color and size. A single, low concentration of GA3 combined with Ca sprays enhanced Ca uptake, cracking resistance, and FF without delaying maturation. When Ca plus GA3 sprays were reduced to four times, Ca uptake was retarded, but had an equal or greater benefit than Ca sprays alone. The 5-d harvest delay in combination-treated fruit did not affect skin color, but these fruit had reduced Ca levels at harvest and displayed stem browning after storage.

Effect of some Micro-nutrients, Silicon and GA3 Spraying on Yield and Fruit Quality of Pomegranate

Little is known about the response of pomegranate to the foliar application with nutrients and gibberellic acid. A randomized complete block design (RCBD) experiment was conducted on 40-years old Manfalouty pomegranate trees grown on Upper Egypt. The study aims to investigate the effect of foliar application with gibberellic acid (GA3), potassium silicate (PS), zinc sulphate (ZS) and fetrilon compi (FC) which is a mixture of micronutrients on fruiting of pomegranate trees.