Search

Rose is a commercial flower crop widely grown across India. It is highly sensitive to salinity and alkalinity. In the process of identification of salt and alkalinity resistant rootstocks of rose cultivars, a survey was conducted in the rose growing areas of Uttar Pradesh (UP) and Rajasthan. Total of 28 representative surface soil samples were collected from rose fields of these regions, processed and analyzed for the soil quality parameters. Similarly water samples (20 samples) from the bore wells of these fields were collected and analyzed. The results revealed that most of the soils of rose growing fields in UP were alkaline (pH >8.0) with normal salt content (electrical conductivity, EC < 0.5 dS m-1). Many of these soils also had higher bicarbonates (> 3 meq 100 g-1). In case of Rajasthan, few samples had higher pH, EC, chloride (>2 meq 100 g-1) and bicarbonate contents. Exchangeable sodium percentage (ESP) of UP and Rajasthan samples ranged from 5.21-20.7% and 2.94-24.9%, respectively. In case of water parameters in these areas, pH was slightly in alkaline range, EC of some of the samples were high (>1 dSm-1). Sodium content was slightly higher than other cations. Soluble sodium percentage (SSP) of water samples was also slightly higher than normal range (0-50%). Few samples had slightly higher chloride above the threshold limit. From the results, it is concluded that soil and water quality of the rose growing areas of UP and Rajasthan is marginal and proper management/reclamation measures need to be carried out for sustaining the production system.

Resistance responses in the leaves of eight rose genotypes, Knock Out (highly resistant), Arka Nishkant (moderately resistant), R. multiflora (highly susceptible), Arka Swadesh (highly susceptible), IIHRR 13-4 (susceptible), Arka Parimala (susceptible), R. indica (susceptible) and IIHRR 4-15-12 (moderately susceptible), exhibiting varied levels of resistance against black spot were investigated post artificial inoculation with black spot pathogen, Diplocarpon rosae. There was consistent increase in the activities of defense related enzymes such as catalase, peroxidase, polyphenol oxidase, superoxide dismutase and phenylalanine ammonia lyase and other defense related secondary metabolites like phenols and flavonoids at different phases of black spot progression and increase was high in resistant genotypes Knock Out and Arka Nishkant. The peak activity of defense enzymes and high concentration of other metabolites was witnessed during early stages of infection in the resistant genotypes while it was during later phase in the susceptible genotypes. These results suggested that the faster and stronger activation of defense system is associated with the resistance against black spot in the rose genotypes.

Field experiments were conducted during 2015-17 at ICAR-Indian Institute of Horticultural Research, Hessaraghatta, Bengaluru, to standardize the partial root zone drying irrigation in papaya with 12 treatments in RBD design. The results indicated that better soil moisture in the root zone could be maintained under drip irrigation by shifting laterals on either side at fortnightly intervals as compared to fixed laterals with thesame amount of water. Significantly more primary roots (16.5/plant) were observed when irrigation was scheduled on one side with single emitter meeting 60% of the evaporative demand. PRD irrigation through shifting of laterals recorded significantly higher transpiration rate especially at 50% of ER (8.05 m mol m-2 s-1) as compared to the control (3.95m mol m-2 s-1). Further, the same treatment recorded significantly lower fruit cavity index (0.26) with relatively higher fruit volume (1388 cm3). Irrigating papaya only on one side with single emitter resulted in significantly higher T.S.S (13.0%). Higher water productivity (23.7 kg/m3) could be obtained by scheduling the irrigation at 40% evaporation replenishment through shifting of laterals with saving of substantial water (1285m3/ha) resulting in higher water use efficiency (237.4 kg/ha.mm).

Little is known about rate of photosynthesis, transpiration, stomatal conductance, intrinsic water use efficiency, endogenous phytohormones (Gibberellic acid and Indole acetic acid) concomitant with leaf chlorophyll content during flowering and fruiting stages in pomegranate. As a result, a study was conducted to determine the function of various chemicals, such as Nitrobenzene (NB) at 1.0, 1.5, and 2.0 ml plant-1, Cycocel (CCC) at 500, 1000, and 1500 ppm plant-1, Uracil 25 and 50 ppm plant-1, CCC1000 ppm + Uracil 25 ppm plant-1, CCC 1500 ppm + Uracil 50 ppm plant-1, along with control at ICAR - Indian Institute of Horticultural Research (IIHR), Bengaluru, during the flowering and fruit set stages during two seasons, namely ambe bahar (January-February 2016) and hastha bahar (September-October 2016-17). Applications of Uracil 50 ppm plant-1, Uracil 25 ppm plant-1 and nitrobenzene 1.5 ml plant-1 at flowering stage resulted in highest rate of photosynthesis (16.48 µmol m-2 s-1), transpiration (7.69 mmol m-2 s-1) and stomatal conductance (0.44 mol m-2 s-1). Foliar spray of Nitrobenzene 1.5 ml plant-1, cycocel 1000 ppm plant-1 + Uracil 25 ppm plant-1 in conjunction with application of nitrobenzene 1.0 ml plant-1 registered highest rate of photosynthesis (12.55 µmol m-2 s-1), transpiration (6.19 mmol m-2 s-1) and stomatal conductance (0.19 mol m-2 s-1) at fruit set stage. Application of Uracil 50 ppm plant-1 resulted in higher levels of endogenous IAA content (394.3 ng g-1 FW and 885.3 ng g-1 FW), lower levels of GA3 content (110.7 ng g-1 FW and 144.0 ng g-1 FW), and highest total chlorophyll content (3.14 mg g-1 and 1.99 mg g-1) in the leaves at both flowering and fruit set stages. With application of cycocel 1500 ppm plant-1 at flowering and fruit set stages, highest photosynthetic rate (17.67 µmol m-2 s-1 and 15.71 µmol m-2 s-1), transpiration rate (7.68 mmol m-2 s-1 and 6.13 mmol m-2 s-1) and higher levels of endogenous IAA (946.7 ng g-1 FW and 633.0 ng g-1 FW) were registered respectively. Following application of cycocel 1500 ppm plant-1 and 500 ppm plant-1 at both flowering and fruit set stages, lower endogenous GA3 (163.3 ng g-1 FW and 276.0 ng g-1 FW) were observed. At flowering stage, cycocel 1000 ppm plant-1 + Uracil 25 ppm plant-1 recorded the highest total chlorophyll content (2.35 mg g-1). During flowering period, cycocel 1500 ppm plant-1 application resulted in the highest stomatal conductance (0.57 mol m-2 s-1). Application of cycocel 1500 ppm plant-1 + Uracil 50 ppm plant-1 resulted in the highest stomatal conductance (0.38 mol m-2 s-1) at fruit set stage. [ABSTRACT FROM AUTHOR]

The effect of different plant growth regulators on flowering, fruiting, yield, and quality of pomegranate (Punica granatum L.) cv. Bhagwa was studied in a field trial at ICAR - Indian Institute of Horticultural Research (IIHR), Bengaluru, during two seasons, namely ambe bahar (January-February) 2016 and hastha bahar (September-October) 2016-17. Nitrobenzene (NB) 1.0, 1.5, and 2.0 ml plant-1, Cycocel (CCC) 500, 1000, and 1500 ppm plant-1, Uracil 25 and 50 ppm plant-1, CCC 1000 ppm + Uracil 25 ppm plant-1, CCC 1500 ppm + Uracil 50 ppm plant-1, and Control were among the eleven treatments studied. The application of uracil 50 ppm plant-1 resulted in a higher number of hermaphrodite flowers plant- 1 (264.7), number of fruits plant-1 (154.0), and fruit yield (27.1 kg/plant). Fruit weight (197.6 g), fruit length (6.64 cm), total aril weight (113.63 g), 100 aril weight (27.18 g), fruit juice weight (101.94 g), TSS content (19.96 OB), fruit anthocyanin content (6.46 mg 100 g) and low titrable acidity (0.41 percent) were recorded when CCC 1000 ppm + Uracil 25 ppm plant-1 was applied. During ambe bahar, the highest fruit width (6.90 cm) and volume (162.7 ml) were observed with CCC 1000 ppm and 1500 ppm plant-1, respectively. During hastha bahar, CCC 1500 ppm plant-1 resulted in a higher number of hermaphrodite flowers (287.8), the highest percentage of fruit set (86.10), the highest number of fruits plant-1 (156.66), the highest fruit yield (54.53 kg plant-1), the highest fruit weight (348.32 g), the longest fruit length (8.53 cm), and the largest fruit volume (8.53 cm) (33.93 ml), total aril weight (224.01 g), 100 aril weight (35.09 g), fruit juice weight (119.40 g) and TSS content (16.00 OB). A foliar spray of nitrobenzene 1.5 ml plant-1 compounded the high fruit anthocyanin content (6.47 mg 100g-1). As a result of the research, it can be concluded that CCC 1000 ppm + Uracil 25 ppm plant-1and CCC 1500 ppm plant-1were the most effective treatments for improving floral characters, fruiting, yield, and quality in pomegranate cv. Bhagwa during both seasons. [ABSTRACT FROM AUTHOR]

The field trail was conducted at ICAR-IIHR, Bengaluru to assess the effect of different chemicals (Nitrobenzene @ 1.0 ml, 1.5 ml and 2.0 ml/litre, Cycocel @ 500 ppm, 1000 ppm and 1500 ppm, Uracil @ 25 ppm and 50 ppm, Cycocel @ 1000 ppm + Uracil @ 25 ppm and Cycocel @ 1500 ppm + Uracil @ 50 ppm) on flower induction, fruiting and yield parameters in tissue cultured plant propagules of pomegranate (Punica granatum L.) cv. 'Bhagwa' during 2016-17 at ICAR-IIHR, Bengaluru. The foliar application of Cycocel @ 1500 ppm gave a significantly increased number of hermaphrodite flowers (287.84) and intermediate flowers (254.14) per plant, thereby increasing the percentage of fruit setting (86.10 %) and number of fruits (156.66) per plant. Thus fruit yield (54.53 kg/plant and 21.81 tonnes/ha), fruit weight (348.32 g), fruit length (8.53 cm) and fruit volume (333.93 ml) increased significantly. Consequently, foliar application of Cycocel @ 1500 ppm led to a significant reduction in number of male flowers (219.70) produced per plant. However, fruit width was non-significant among treatments. [ABSTRACT FROM AUTHOR]

Dominant vegetative phase, if not regulated, can adversely affect the mango production particularly under high density planting systems. Pruning after fruit harvest and use of paclobutrazol (PBZ) have been identified as common strategies for tree vigour regulation and productivity enhancement in mango. The objective of the present study was to investigate the effects of 50% pruning of current and previous season vegetative growth and PBZ (3 mL/ m canopy diameter) on tree vigour, flowering and phenol contents in three mango cvs. Raspuri, Dashehari and Amrapali. Suppression of plant height, tree girth, canopy spread, shoot length and girth was witnessed with PBZ application in trees pruned to 50% of current season growth followed by trees pruned to 50% of previous season growth and unpruned trees. Early flowering witnessed as a result of PBZ application led to advanced fruit harvest by 20.4, 13.0 and 14.7 days in trees pruned to 50% of current season growth and 18.7, 13.7 and 15 days in trees pruned to 50% previous season growth in the cvs Raspuri, Dashehari and Amrapali, respectively. Drastic increase in total phenols, total flavonoids and phenolic acid contents were observed at 75 days after PBZ application in PBZ treated unpruned trees and in trees pruned to 50% of current season growth followed by in trees pruned to 50% of previous season growth. The high levels of o-coumaric acid, 4-hydroxy benzoic acid and salicylic acid and low levels of caffeic acid and t-cinnamic acid were observed following PBZ application in tree pruned to 50% of current season growth and unpruned trees compared to control. From the study it was apparent that the pruning of trees to 50% of current season growth and PBZ application are vital for regulating tree size, early flowering and advancing fruit harvest in mango and such beneficial effects of treatments were mediated through increases in phenols and flavonoids contents. [ABSTRACT FROM AUTHOR]

Effects of tree spacing (5x2 m, 5x2.5 m, 5x3 m, 5x3.5 m and 5x4 m) and pruning (8 buds/cane, 6 buds/cane and 4 buds/cane) on growth, physiological parameters, fruit yield and quality were studied in fig cv. Poona during 3rd and 4th years of planting. Results indicated that the fig responded more to tree spacing than the pruning levels in terms of morpho-physiological characters and yield. With increase in in-row tree spacing from 5x2.5 m to 5x4 m, the vegetative growth parameters like leaf number, shoot length, internodal length, tree spread, tree height and tree circumference and the fruit yield both in terms of fruit number and fruit weight per tree declined under different pruning levels and closer tree spacing of 5x2.5 m recorded higher values. Physiological parameters like photosynthesis rate and leaf water potential remained at higher levels under closer spacing as compared to the wider spacing under different pruning levels. The increased pruning levels from 8 buds/cane to 4 buds/cane resulted in reduction of tree height while yield characters were marginally influenced by the pruning. The interaction effects between pruning and spacing levels were, however, non-significant. Under 5x2.5 m, the average fruit size and TSS recorded the highest values with no marked differences in acidity. The fruit yield calculated on per tree basis showed highest fruit number of 84.3-253.0 and 232.3-321.5 and fruit weight of 2.69-8.61 and 7.43-9.44 kg, respectively during 3rd and 4th year of planting under closer spacing of 5x2.5 m with 8 buds/cane pruning. The yield per hectare under various pruning levels recorded high values under the closer spacing of 5x2.5 m or 5x2.0 m with 8 buds/cane pruning. Overall results showed that 5x2.5 m tree spacing in combination with light pruning level of 8 buds/cane is ideal for achieving higher growth and yield in fig during 3rd and 4th year of planting. [ABSTRACT FROM AUTHOR]

Studies were conducted at Indian Institute of Horticultural Research, Bangalore, India, to compare the role of carbohydrate and its metabolizing enzymes in “off” season bearing cultivar Royal Special and regular bearing cultivar Totapuri during the time of flowering. Totapuri is a regular bearing cultivar mainly used for processing and has high yielding potential. “Off” seasonal cropping in mango is the unique feature of mango cultivar Royal Special which contributes to “off” season mango production under South Indian conditions. During the bud swelling stage, the maximum reducing sugars contents were recorded while higher chlorophyll a and b values were recorded during bud break stage in ‘Royal Special’ as compared to ‘Totapuri’. Higher acid invertase activity was recorded during emergence of panicles, and increased amylase activity was observed during pre-swelling stage in ‘Royal Special’. Sucrose and its metabolizing enzymatic activities increased during flowering, indicating their decisive role in the flowering process in the case of both cultivars of mango. [ABSTRACT FROM PUBLISHER]

The present study, aimed at advancing Alphonso mango harvest season through manipulation in time of soil application of paclobutrazol (PBZ) [soil application on 15th of May, June, July, and August]; foliar spray of KNO3 (3%) [August and September], was conducted during 2010 to 2012 cropping seasons in red lateritic rocky soil of Konkan (Maharashtra, India). Results of individual years and mean for three years revealed that significant earliness in flowering (85.4 day) and advancement in harvesting (82 day) was achieved with the application of PBZ on 15th May. PBZ application on 15th June was relatively less effective in inducing early flowering (56 day) and harvesting (69 days). However, the greater extent of flowering (72.23 %) and fruit yield per tree (40.72 kg/tree) were recorded with PBZ applied at recommended time i.e., on 15th August. Individual fruit weight was higher in KNO3 sprayed tree in the months of August (268g) and September (265.5 g), whereas fruit T.S.S. was higher (19.37 ºBrix.) in trees receiving PBZ on 15th August. The findings of study indicated huge potential for realizing about 5-6 times higher returns from Alphonso produced in February-March months as compared to May harvest. [ABSTRACT FROM AUTHOR]