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Evaluation and quantification of fruit quality parameters like carbohydrates, phenolics, flavonoids, ascorbic acid, titrable acidity, Total Soluble Solids (TSS), carotenoids and lycopene content was done in fruits of mango cv. Royal Special, at ICAR-Indian Institute of Horticultural Research, Bengaluru, India, during the off-season (October, 2012) and main-season (June, 2013), respectively. 'Royal Special' is a typical off-season bearing cultivar, often characterized by multiple flushing and flowering under South Indian conditions. Major phytonutrients such as total sugars, reducing sugars, starch, total carotenoids, lycopene, total phenols, flavonoids, ascorbic acid, TSS, titrable acidity and average fruit yield per plant, were recorded during the off- and main- seasons. Results indicated that fruits from off-season were higher in the major chemical constituents studied compared to the main-season crop, except for fruit yield per plant. This may be attributed to poor competition for nutrients among the developing fruits which act as a sink, besides fluctuating environmental conditions during the off-season, compared to the main-season.

The effects of tree spacing (5x2m, 5x2.5m, 5x3m, 5x3.5m and 5x4m) and pruning (8 buds/cane, 6 buds/cane and 4 buds/cane) on vegetative growth, physiological parameters, fruit yield and quality were studied in fig (Ficus carica L.) cv. Deanna in the 3rd and 4th year of its growth during the period 2010-12. It was observed that with increase in tree spacing, growth parameters like leaf number, shoot length, internode length, tree-spread, tree height and tree circumference, along with fruit yield both in terms of fruit number and fruit weight per tree, declined gradually under different pruning levels. Increase in pruning level from 8 buds/cane to 4 buds/cane resulted in increased leaf number, shoot length and internode length. Yield characters, viz., fruit number/tree, fruit weight/tree, fruit number/hectare and fruit weight/hectare were marginally influenced by pruning. However, interaction effects of pruning and spacing were found to be non-significant. Consistently declining trends in photosynthesis rate and stomatal conductance, along with increase in leaf water potential value were observed with increase in spacing. Effects of spacing were more conspicuous than those of pruning. Best results for maintenance of vigour and fruit yield were observed under a spacing of 5x2m or 5x2.5m, and 4 buds/cane pruning. Although there was reduction in average fruit size under closer spacing when compared to wide spacing, fruit quality attributes like TSS and acidity were not affected by various treatments. Effects of closer spacing on growth and yield parameters were more pronounced in the 3rd year as compared to the 4th year, showing better response to treatments in young trees. Fruit yield calculated on per hectare basis showed highest fruit number of 116500-133750 and 274500-299500, and fruit weight of 54.5-62.0 and 158.77- 173.30 quintals/ha, respectively, during the 3rdand 4th year of planting under closer spacing of 5x2m and 4 buds/cane pruning.

Paclobutrazol application restricts vegetative growth while improving flowering and fruiting in mango. In the present study, effect of soil drenching with Paclobutrazol @ 3.0ml m-1 canopy diameter, applied during the 3rd week of August, on fruit quality attributes was investigated in cv. Totapuri. Parameters like fruit weight, total soluble solids (TSS), % acidity, and content of ascorbic acid, carotenoids, lycopene and individual sugars was estimated. Paclobutrazol application increased average fruit weight, TSS and content of ascorbic acid and total carotenoids, and reduced the acidity in fruits compared to fruits in untreated trees. Lycopene content was only marginally influenced by paclobutrazol. In fruits of paclobutrazol treated trees, increase of 23.4% in total sugars, 29.6% in reducing sugars, 77.4% in glucose and 27.8% in sucrose content was recorded over fruits from the untreated trees. Results indicated that, paclobutrazol application improved quality in mango fruit.

The present review provides an insight into the relationship between plant growth regulators and water stress with emphasis on metabolic events that regulate growth regulator balance and physiological responses. Possible mechanisms by which ABA controls stomatal function and growth under stress, and interacts with proteins and important osmo-protectants, have been discussed. ABA involvement in signal transduction and root-shoot communication through its effects on gene and gene products is also included. A brief description of involvement of other growth regulators such as cytokinins, ethylene, polyamines and brasssinosteroids in water stress tolerance is also provided. Salient achievements in exploiting the potential of growth regulators in the resistance to water stress in some horticultural crops are also given. Gaps in existing information on plant growth regulator research in water stress tolerance have been summarized.

Studies on root and shoot morphology, endogenous hormones and water use efficiency in five grape rootstocks namely Dogridge, 1613 C, Salt Creek, St. George and Vitis champinii clone (VC Clone) at three levels of moisture stress viz., no stress (100% irrigation), 50% stress (50% irrigation) and 100% stress (without irrigation) for 14 days revealed that Dogridge and Salt Creek rootstocks maintained the highest ratios of root to shoot length and root to shoot dry weight as compared to other rootstocks. Water use efficiency increased with increased soil moisture stress and was the highest in Dogridge and Salt Creek. The abscisic acid content in the leaves of Dogridge was maximum at 50% stress followed by that of Salt Creek. Similarly the cytokinin content (both t-ZR and DHZR) was minimum in Dogridge and Salt Creek at 50% stress while it was maximum in 1613 C and St.George. The root to shoot length ratio was positively correlated with ABA content under moisture stress conditions. The higher levels of abscisic acid content in Dogridge and Salt Creek under soil moisture stress suggested their better drought tolerance capacity through a reduction of stomatal conductance and increased water use efficiency.