Plant Bioregulators Research Articles

Effect of plant bioregulators on yield and quality of Kinnow mandarin

Effect of plant bioregulators was assessed on yield and quality of Kinnow mandarin (Citrus reticulata Blanco.) in the subtropical climate of Jammu. The trial was laid in randomized block design and the experiment comprised of ten plant bioregulator treatments replicated thrice. Least fruit drop (16.21%) and maximum fruit yield (31.10 kg/tree) was recorded with 20 ppm 2, 4-D application. However, maximum fruit weight (109.30 g), fruit length (66.90 mm), fruit diameter (76.70 mm), fruit volume (113.89 cm3) and juice percentage (55.80%) was recorded with 75 ppm GA3. Among different chemical parameters highest TSS (12.70 °B), acidity (1.38%), reducing sugars (3.48%), non-reducing (5.06%) and total sugars (8.65%) were observed under 15 ppm NAA application. Among the treatments applied, 20 ppm 2, 4-D resulted in least fruit drop, however fruit quality was better with the application of 75 ppm GA3 and 15 ppm NAA application.

Effect of plant bioregulator and chemical treatment on germination of papaya (Carica papayaL.) cv. Pusa Nanha

Bio inoculants have a synergistic effect on plant growth. Plant bioregulators and chemical treatment application for germination and seedling growth of papaya (Carica papaya L.) cv. Pusa Nanha was evaluated in the present study. The maximum percentage of germination was obtained in seed treated with KNO3+soaked in water + incubated in Farm Yard Manure (FYM)followed by T3 (Untreated + Soaked in water + incubated in FYM) and T12 (Treated Na2S2O3.5H2O for 24 h + incubated in FYM for 24 h). The maximum speed of germination or coefficient of velocity was obtained from T3 (Untreated + Soaked in water + incubated in FYM). Results indicate a promoter role of incubation of seed with bio inoculants, viz., potassium nitrate (KNO3) and FYM for seed germination in papaya.

Effect of plant Bio-Regulatores on Growth, Flowering and Seed yield in China Aster (Callistephus chinensisL. Nees) CV. Kamini

A field experiment was conducted to study the effect of plant bio regulators on growth, flowering and seed yield in China aster cv. Kamini at College of Horticulture, Rajendranagar, Hyderabad during rabi, 2013–14. The experiment was laid in randomized block design and replicated twice. Plant growth regulators viz., GA3, salicylic acid, maleic hydrazide, alar and paclobutrazol were used in the experiment. The treatments were imposed as foliar sprays twice at 20 and 35 days after transplanting. The observations on growth parameters were recorded at three stages of plant growth viz., 30, 60 and 90 DAT. GA3 200 mg/l spray recorded significantly higher plant height (60.10 cm), number of primary branches per plant (24.60) and number of secondary branches per plant (61.45) at 90 DAT, number of flower's per plant (84.96), flower yield per plant (109.66 g), flower yield per hectare (16.58 t), seed yield per plant (9.98 g), seed yield per ha (1509.31 kg) and 1000 seed weight (2.01 g). GA3 200 mg/l foliar spray was found to be at par with SA 200 mg/l in respect of number of primary branches (23.86), flower yield per hectare (15.90 t), seed yield per plant (9.85 g) and seed yield per hectare (1489.65 kg). SA 200 mg/l foliar spray could be recommended for increased growth, flower and seed yield in China aster cv. Kamini as it is more cheaper than GA3.

Influence of plant bio-regulators on yield, physico-chemical attributes and post harvest quality of pear cv. Gola underTerairegion of Northern India

Terai region of northern India is having great potentiality for growing low chilling cultivars of different temperate fruits as this region receives sufficient amount of low temperature every year. However, the major problems of low chill cultivars are small fruit size, along with poor physico-chemical quality attributes. The present investigation was aimed at addressing these problems. For determining the influence of plant bio-regulators CPPU (5 and 10 ppm), NAA (10 and 20 ppm) and salicylic acid (50 and 100 ppm) were applied as once, twice and thrice spray at fortnightly interval after fruit set. CPPU @ 10 ppm was found most effective for increasing fruit length (6.79 cm), width (6.67 cm), fruit weight (182.84 g) and volume (179.11 ml), while TSS (13.38°Brix), total sugars (8.25%), acidity (0.55%), number of fruits per tree (285.00) and yield (47.66 kg) were found better with the application of CPPU @ 5 ppm. Higher per cent of marketable fruits (86.56) and ascorbic acid (7.08 mg/100 g) content was found in SA @ 100 ppm treatment.

Impact of Foliar Application of Plant Bioregulators on Morphological, Floral and Yield Traits in Bottle Gourd [Lagenaria Siceraria(Molina) Standl.] CV. Pusa Naveen

The present investigation entitled “Impact of foliar application of plant bioregulators on morphological, floral and yield traits in bottle gourd was conducted at the Horticultural Research Centre of SVPUA & T, Meerut, U.P. The experiment was laid out in Randomized Block Design with three replications. The field experiment consisted of five concentrations each of GA3 (5, 10, 20, 50 & 75 ppm), Ethrel (50, 75, 100, 150 & 200 ppm), NAA (50, 75, 100, 150 & 200 ppm) and control (Water Spray) were applied at 2 and 4 leaf stages on bottle gourd cv. Pusa Naveen during the years of 2013 and 2014. It was observed that GA3 75 ppm registered the maximum vine length (4.96 m) and Number of primary branches (22.01) in comparison to all other treatments. Whereas, Ethrel 200 ppm improve the female flowering time (44.46 days), narrower the sex ratio (1.30), increase the number of fruits per vine (9.95) and total yield (357.42 q/ha) followed by NAA 200 ppm and GA3 5 ppm.

Efficacy of GA3on growth and flowering regulation ofin vitroraised hybrid gerbera under shade net

Study was carried out to find out the effect of plant bioregulators on growth and flower of in vitro raised hybrid gerbera plants under shade net. The findings of the investigation revealed that GA3 100 ppm accelerated both vegetative growth and flowering characters such as stalk length, number of flowers per plant, flower diameter throughout the investigation period from January to June 2011.

Flowering, fruiting, yield and physical character of fruit of mango cv. DASHEHARI as influenced by pre-harvest foliar spray of nutrients and plant bio-regulators

The experiment was carried out in the orchard situated in district Saharanpur (U.P.) during the years 2010 and 2011 with an aim to improve the yield and physical characters of mango fruit. The treatments were comprised of mulching, borax @ 0.5 and 1.0%, potassium sulphate @ 0.5 and 1.0 %, calcium chloride @ 0.5 and 1.0 %, calcium nitrate @ 0.5 and 1.0 %, GA3 @ 25ppm and 50 ppm, NAA @ 25ppm and 50 ppm in combination with mulching and water spray without mulching as control. The spray was done three times at different stages during the year 2010 and 2011 which is given below-Ist spray on 15th January (i.e. before flower bud burst), IInd spray on 15th February (i.e. at panicle emergence) and IIIrd spray on 15th April (i.e. after fruit set). The findings of experiment were indicated that the application of borax @ 0.5 % along with mulching was most effective for increasing fruit quality. The shelf life of fruits was significantly increased by the application of growth regulators.

A metabolomics approach to unravel the regulating role of phytohormones towards carotenoid metabolism in tomato fruit

Carotenoids are important secondary metabolites, which have been recognized as an essential component of the human diet because of their valuable beneficial health effects. With this rationale, there is a continuous aim to define the distribution of these compounds in plants, to better understand their metabolism and to increase their concentration levels in fruits and vegetables. This study aimed at deepening the knowledge on the regulatory role of phytohormones in carotenoid metabolism. More specifically, it was envisaged to reveal the phytohormones involved in the metabolism of α-carotene, β-carotene, lycopene, lutein and zeaxanthin. To this purpose, the phytohormone profiles of 50 tomato fruits were determined by high-resolution Orbitrap mass spectrometry and evaluated towards the associated carotenoid levels. Data mining was performed by differential expression and orthogonal partial least squares analyses. This metabolomics approach revealed 5 phytohormonal metabolites, which significantly influenced (Variable Importance in Projection scores ≥0.80) carotenoid metabolism. These metabolites were identified as cis-12-oxo-phytodienoic acid, cucurbic acid, 2-oxindole-3-acetic acid, 1-acetylindole-3-carboxaldehyde, and cis-zeatin-O-glucoside. The involvement of the individual phytohormones towards carotenoid metabolism was investigated by regression analysis (P values ≤0.05, R2 varying between 0.280 and 0.760) and statistical correlation (P values ≤0.01, correlation varying between 0.403 and 0.846). It was concluded that these phytohormones all have significant contributing value in the regulation of carotenoid metabolism, thereby exhibiting down- and up-regulating influences. As a result, this knowledge encloses the potential for improving tomato fruit nutritional quality by targeted control of agronomic conditions, exogenous use of plant bioregulators, or genetic engineering.

USING PLANT BIOREGULATORS TO IMPROVE PRODUCTION AND FRUIT QUALITY OF STRAWBERRY

Hydroponic production of strawberry in greenhouse conditions is ever increasing; however there are still problems such as low yield, poor fruit quality and sensitivity to unfavorable indoor conditions. Use of plant bioregulators in combination with essential elements would not only alleviate these problems but would also have a positive impact on overall growth of plants. Three separated experiments were carried out on strawberry cultivars to assess the effect of salicylic acid (SA), spermidine (Spd), putrescine (Put) and manganese sulfate on vegetative and reproductive growth of strawberry plants. In all researches daughter-rooted plants were potted in plastic pots filled with 1:1 peat moss and perlite, grown in greenhouse, and after their establishment foliar application of treatments was done. In experiment one, the effect of 1, 2 and 3 mM of SA on 'Pajaro' was evaluated. Results showed that 2 mM of SA increased total yield, number of fruits and ascorbic acid concentration. Impact of Spd and Put on 'Paros' and 'Selva' cultivars was investigated in a second study where results indicated that Spd increased chlorophyll content of both cultivars whereas Put decreased it. Polyamines spray caused an increase in diameter and weight of primary and secondary fruits. In the third investigation, the influence of manganese sulfate at two concentrations (1.5 and 3 g L-1) on 'Paros' strawberry was studied: 1.5 g L-1 of manganese sulfate increased number of fruits and vitamin C concentration. So, bioregulators and essential elements have the potential to manipulate growth aspects and therefore might be used to improve the quality and quantity of production, costs and unfavorable side effects should be taken into consideration when recommendations are made. Local studies on local cultivars may be helpful.

English

The results of effect of plant bio-regulators on yield and yield attributing characters of strawberry CV. Chandler showed that at 75 DAT the plant height attained maximum of 20.50 cm, spread (25.53 cm) leaf number per plant (23.00), petiole length (0.20 cm), leaf area (136.30 cm2) and yield (356.56 g/plant) respectively, of strawberry was obtained highest with the application of GA 75 mg/L while, cycocel 750 mg/lresulted in minimum days taken to first flowering (61.66 DAT) and fruit formation (66.66 DAT). The maximum number of flowers per plant were recorded as 30.22 and number of berries (24.80) with application of GA 75 mg/L.   Key words: Chandler, Fragaria x ananassa, bio-regulators, physico-chemical, yield.

Effect of plant bio-regulators on fruit growth, quality and productivity of pear [ Pyrus pyrifolia (Brum.) Nakai] cv Gola under tarai condition

Effect of plant bio-regulators on fruit growth, quality and productivity of pear [ Pyrus pyrifolia (Brum.) Nakai] cv Gola under tarai condition

English

Bioregulators are chemicals that affect the expression of biological responses in plant tissues. Their use is a unique facet of biotechnology and a new approach of manipulating plant biochemistry for enhancing productivity and quality. They act in low concentrations without any biocidal or nutritive action. Applications of bioregulators are reported to reduce biotic and abiotic stress in plants. Recent studies show that their application increases the growth, yield and nutritive value of food crops. Their use at different times or concentrations elicits diverse effects and in some cases significantly alters virus multiplication and pathogenesis. Increasingly, plant bioregulators are being recognised as important tools in pest and disease management. They have been instrumental in understanding morphological and growth phenomena in-vitro and are potential tools for elucidating biochemical pathways in plants. Plant growth and development are influenced by physical, chemical and biological components in the plants’ environment. Though, bioregulators are commonly used to improve plant growth, development, defence and productivity, the molecular mechanisms of their effects still remain to be fully elucidated. This article reviews the biochemical importance of bioregulator application in plants, current state of research on their effects and discusses their roles in insect and pest invasion as well as possible mechanism of action. Key words: Bioregulation, plant growth, plant development, plant improvement, stresses

Effect of growth hormones on some antioxidant parameters and gene expression in tomato

Bioregulators have a great effect on vital processes of plant growth and development. Known plant bioregulators include Naphthalene acetic acid (NAA), Indole-3-butyric acid (IBA) and Indole-3-acetic acid (IAA). Natural or synthetic plant bioregulators are organic compounds that affect the physiological processes in the plant, either to control some of these processes or to modify them. For example these bioregulators can affect the nature of the process, either by accelerating or decelerating plant growth, rates of maturation and also by altering the behavior of the plants or their products. Also, enhancement of important nutrients in human diet could be achieved by bioregulators. This study uses the model crop plant Tomato (Lycopersicon esculentum). Tomato is affected by a group of bioregulators, this group contains compounds which are powerful antioxidants in vitro. The current study aims to find out the effect of some plant bioregulators (IAA, IBA and NAA) on tomato growth, total protein content and enzyme activities of ascorbate peroxidase (APX), superoxide dismutase (SOD) and catalase (CAT). This study also investigates the effect of the above mentioned bioregulators on the level of RNA expression for SOD, CAT and TPX1 genes. The analytical quantification of target gene expression showed the induced effect of NAA on SOD expression and reducing effect of the other bioregulators (IAA and IBA) on CAT and TPX1 expression. However, at the protein level, we found that IBA and IAA caused a minor effect on total protein content while a significant effect was recorded on the total protein level using NAA. Upon measuring the enzyme activity of ascorbate peroxidase and catalase, we found that both the exogenous NAA and IBA stimulated ascorbate peroxidase activity in tomato while there was no considerable difference detected in IAA treated plants. Also, there was no considerable difference detected in catalase activity of all bioregulator-treated plants compared with the control.

Effect of plant bio-regulators on physico-chemical characteristics of three apple varieties 124 during ambient storage

Effect of plant bio-regulators on physico-chemical characteristics of three apple varieties 124 during ambient storage

Interaction between different pre- and postharvest treatments on shelf life extension of ‘Oregon Spur’ apple

Introduction Fruit quality characteristics are governed by preharvest factors, mainly climate, nutrition and plant bio-regulators, of which the latter two can easily be manipulated in the grower’s interest. Likewise, the postharvest treatments with the best performance can maintain quality during storage and distribution. Therefore, it is important to embrace a holistic approach to combine the pre- and postharvest practices in view of attaining maximum quality and satisfaction at the consumer level. Materials and methods . Various combinations of mineral nutrients (calcium and boron) and bio-regulators (salicylic acid and gibberellic acid) were applied at the pre- and postharvest stages of apple fruits to study their influence on postharvest behavior of these fruits during 60 days of storage under ambient conditions. Results and discussions Among the different treatments tried, fruits treated with either salicylic acid or calcium showed significant improvement with regards to improved physico-chemical characteristics and reduced fruit infection percentage. Integration of pre- and postharvest application of chemicals was verified as the most effective choice for the improvement of shelf life of apple fruits amongst the treatment combinations applied either at the pre- or postharvest stage. The application of salicylic acid in combination with calcium or boron renders an alternative to the use of fungicides to control decay during apple fruit storage.

Identification of a new bioregulator acting in ultralow doses in bulb onion (Allium cepa L.)

A bioregulator that has physicochemical and biological properties similar to a group of bioregulators isolated from various animal tissues has been found in the bulb onion (Allium cepa L.). It was determined that the biological action of the plant bioregulator is determined by a peptide with molecular weight of 4036 +/- 2 Da whose 18-C-terminal amino acid sequence consisted of 18 residues. On models of seed germination of some vegetable cultures, the ability of the bioregulator isolated from supernatant of onion extract in ultralow doses (10(-13) mg of protein/ml) to inhibit growth and development was demonstrated.

Influence of Plant Bioregulators on Pecan Flowering and Implications for Regulation of Pistillate Flower Initiation

Mitigation of alternate bearing (AB) through regulation of floral initiation of pistillate flowers is central to improving cropload management of pecan [Carya illinoinensis (Wangenh.) K. Koch] trees and orchards. The present study examines the influence of key bioregulators {i.e., an auxin [as B-napththaleneacetic acid (NAA)], a cytokinin [6-benylamino purine (6-BA)], an ethylene generator (ethephon), and an auxin transport inhibitor [2,3,5-triiodobenzoic acid (TIBA)]} on subsequent season pistillate flowering. Gibberellic acid (i.e., GA3) and NAA inhibited, whereas prohexadione–calcium (P-Ca; calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate), ethephon, and BA + TIBA promoted floral initiation when topically applied to canopies before the kernel filling stage of seed development. These bioregulators exhibit potential for integration into a bioregulator-based strategy to mitigate pecan AB by selective and timely use in “off” or “on” cycle years, depending on the bioregulator. Field studies provide evidence that a “cytokinin–gibberellin balance,” with partial modulation by auxin and ethylene, acts in the endogenous primordial environment of floral meristems as a “second-level signal” regulating a key step in a three-step process for initiation of pistillate flowers in pecan. This establishes a new model for explaining pistillate flower initiation in pecan and a basis for designing future research on the control and management of pistillate flowering and AB.

EFFECT OF PLANT BIO-REGULATORS AND NUTRIENTS ON FRUIT CRACKING AND QUALITY IN POMEGRANATE (PUNICA GRANATUM L.) 'G-137' IN HIMACHAL PRADESH

ISHS II International Symposium on Pomegranate and Minor - including Mediterranean - Fruits: ISPMMF2009 EFFECT OF PLANT BIO-REGULATORS AND NUTRIENTS ON FRUIT CRACKING AND QUALITY IN POMEGRANATE (PUNICA GRANATUM L.) 'G-137' IN HIMACHAL PRADESH

THE DEVELOPMENT AND USE OF PLANT BIOREGULATORS IN TREE FRUIT PRODUCTION

The discovery of plant hormones and their ability to regulate all aspects of plant growth and development were defining moments in horticulture. Plant bioregulators (PBRs) were soon identified that could improve yield, quality and postharvest life. No where has their impact been more vividly chronicled than in tree fruit production. Tree fruit are considered high value crops and even small modifications in production efficiency, product quality or enhanced cosmetic appeal have the potential to significantly increase product value. Following the discovery of auxins, NAA was found to both to useful in counteract two of the most serious problems of apple production, biennial bearing and preharvest drop. NAA continues to be an important PBR. The discovery of gibberellins and cytokinins led to commercial uses of products in these hormone categories that include improved shape of fruit, enhanced market value by reducing blemishes, improved tree architecture that may be accomplished the by overcoming apical dominance. PBRs were later discovered that could either advance ripening or extend postharvest life, thus greatly expanding the effective period when high quality fruit could be harvested and marketed. Other areas of fruit production where PBRs are especially useful include prevention of preharvest fruit drop, control of vegetative growth, enhanced flower bud formation and control of fruit ripening. Future uses of PBR will emerge. Prohaxadione calcium, an inhibitor of gibberellin biosynthesis, not only retarded shoot growth but it can also alter plant metabolism to impart resistance to insects and diseases. The naturally occurring hormone abscisic acid is showing potential for overcoming plant stress and also enhancing early fruit drop. Recently 1-MCP, a competitive inhibitor of ethylene, has revolutionized storage of pome fruit by extending the postharvest life and improving storage quality of fruit. Recently, great progress in PBR use has come in areas of fruit thinning and retardation of preharvest drop. In these areas greater understanding of fundamental processes, the use of molecular biology techniques and continued empirical research has lead to more effective control of these important process in tree fruit production.

1-MCP CAN PREVENT ETHYLENE-INDUCED DAMAGE TO FRUIT TREES DURING COLD STORAGE

At present, about 50% of the young fruit trees is stored for more than one month in cold rooms between lifting in the nursery and planting in spring in the orchard with a maximum storage duration of 5-6 months. Storage of fruit trees requires the absence of ethylene in the storage room, as this gaseous plant growth regulator may induce damage to the trees during storage, which eventually may lead to the death of branches or the whole trees after planting the tree in the orchard. In 2007 a series of experiments was carried out to find out the sensitivity of ‘Conference’ pear trees to ethylene. In addition, the possible use of 1-MCP treatment before storage of the pear trees was examined as a means to prevent ethylene-induced damage. Tree damage was monitored during and directly after storage as well as after planting the trees in the orchard in spring following the storage period in winter. Ethylene-induced symptoms are the discoloration and death of local areas of bark tissue, death of buds and the occurrence of local cracks in the bark followed by the growth of callus tissue. Ethylene-induced damage was observed only when trees were exposed to 5 mg/L ethylene for 1 month at a temperature of 4°C. No damage occurred in case trees were only exposed to this concentration for 1 week at 4°C or for up to 1 month when stored at a temperature of 0°C. Trees treated with 1-MCP before storage did not develop any damage when exposed to 5 mg/L ethylene for 1 month at 4°C, demonstrating that 1-MCP is also taken up by trees harvested after leaf drop. Sensitivity towards ethylene seemed to be dependent on the time of lifting of the trees in the nursery. A trend was observed that trees grubbed in January developed less symptoms after a month exposure to 5 mg/L ethylene at 4°C than trees given the same treatment but lifted in November or March. This suggests that fully dormant trees are less sensitive to ethylene than trees lifted in autumn or spring. Amelioration of the damage after planting the trees in the field was strongly dependent on the amount of damage occurred during storage. Trees with only a little damage recovered quite well, but those with more severe damage often did not recover. Branches or even the whole tree died as result of the damage symptoms developed during storage. Trees treated with 1-MCP before storage showed a normal development after planting in the orchard and were indistinguishable from the untreated control trees. Further research is needed to more accurately determine the concentration, duration and temperature during exposure at which ethylene becomes harmful to pear trees in storage in order to prevent damage and optimise the use of 1-MCP. INTRODUCTION In the Netherlands many growers prefer to plant young fruit trees in spring when soil and weather condition are usually better than those in the autumn or early winter. At present, about 50% of the young fruit trees planted in spring is stored in cold rooms for more than one month between the moment of lifting in the nursery and planting in spring, with a maximum storage duration of 5-6 months. Occasionally, this cold storage results in damage to the young fruit trees, especially in ‘Conference’ pear trees. Visible damage occurred as local areas of discoloured bark tissue, death buds, and local cracks in the bark Proc. XI IS on Plant Bioregulators in Fruit Production