Mango is an important fruit crop of India grown in an area of 12.22 million ha with production of 104.1 million tonnes (NHB, 2009). In mango, the average national productivity is around 6.42 t/ha, which is very low compared to countries like Israel, Mexico, Brazil and Philippines. One of the reasons for this low productivity is presence of several old, senile mango orchards. Improving the productivity of old, unproductive mango orchards plays an important role in augmenting production and productivity of mango in the country. In old and dense mango orchards, light interception and photosynthetic potential of trees is reduced. Thinning of overcrowded branches to facilitate air circulation improves photosynthetic efficiency, fruit yield and quality. Lakso (1980) reported a close relationship between light interception, photosynthesis and fruit yield in fruit tree orchards. Gross (1997) reported judicious pruning of mango trees for maintaining a good balance between vegetative growth and fruiting. Beneficial and favourable effects of pruning in mango have been reported on light interception and chlorophyll content of leaves (Schaffer and Gauye, 1989), growth parameters (Lal et al, 2001) and fruit yield (Lal and Mishra, 2007; Rao and Shanmugavelu, 1976; Burondakar et al, 1997; Shinde et al, 2003), fruit colour (Whitey, 1984) and regularity in bearing (Rao, 1971) ‘Alphonso’ is one of the commercial varieties of Studies on rejuvenation of old, unproductive ‘Alphonso’ mango trees in orchards Y.T.N. Reddy and Reju M. Kurian Division of Fruit Crops Indian Institute of Horticultural Research Hessaraghatta Lake P.O., Bangalore-560089, India Email: nreddy@iihr.ernet.in ABSTRACT A field trial on pruning was conducted from 2004 to 2009 to induce rejuvenation of twenty six year old, unproductive ‘Alphonso’ mango trees, at Indian Institute of Horticultural Research, Bangalore. In the study, three treatments imposed comprised of two pruning treatments, namely 30cm and 45cm pruning of third order branches from the point of origin, and a control (no pruning). Pruning increased the mean cumulative fruit yield for four years, which was almost double that of control, although the two pruning treatments were on par. Maximum mean cumulative fruit yield (86.3kg/plant) was obtained with 30cm pruning, whereas control treatment recorded a fruit yield of 47.2kg/plant. Fruit quality attributes such as average fruit-weight, TSS, acidity and shelf-life were not affected by the two pruning treatments, for rejuvenation of ‘Alphonso’ mango. Key words: Pruning, rejuvenation, mango, fruit yield, fruit quality mango mainly grown in the states of Karnataka, Maharastra, Tamil Nadu, Gujarat and Andra Pradesh. It is a dual purpose variety used both for table purposes and processing. It is also exported to other countries. In Alphonso, productivity is around 4.5 t/ha, which is very low compared to other mango varieties, due to many reasons. With this in view, rejuvenation through pruning was applied in the existing, old Alphonso trees at Indian Institute of Horticultural Research, Bangalore. A field trial was conducted from 2004 to 2009 on twenty six year old Alphonso mango trees where the fruit yield was around 40 to 50 kg/plant. The trees were under rainfed conditions on red loam soils, with available soil nitrogen 262 kg/ha, available soil phosphorus 9.62 kg/ha and available soil potash 141.1 kg/ha under pH 7.26. The plants were spaced at 10mx10m. Three pruning treatments were imposed, namely, 1. Pruning of third order branches 30cm from origin. 2. Pruning of third order branches 45cm from origin and 3. No Pruning (Control). The treatments are illustrated in the following figure: The pruning treatments were decided and fine tuned based on earlier experience under an NATP trial where branches 5m and 4m from ground level were pruned for improving productivity of Alphonso mango orchards. Regular and uniform cultural practices were imposed on pruned and Short communication J. Hortl. Sci. 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The trial was laid out in Randomized Block Design with 10 replications and single tree as a unit/ treatment. Pruning treatments were imposed during September, 2004 and trees were pruned with a hand-saw. After pruning, the cut ends were applied with copper oxychloride paste. This was followed by three insecticidal sprays after emergence of sprouts, at intervals of 20 days, for control of shoot borer and other pests. Shoots were thinned to manageable levels thus avoiding overcrowding and only the healthy and vigorous ones were retained. No flowering was observed during December 2004/ January 2005 in any of the pruned trees. Fruit yield and quality parameters were recorded during the fruiting season (May- June) of 2006 to 2009, and data were statistically analyzed as per standard procedures (Panse and Sukhatme, 1985). Fruit quality parameters were estimated as per standard procedures (Ranganna, 1986). Fruit yield: Fruit yield as influenced by different pruning treatments during 2006 - 2009 are presented in Table 1. Fruit yield in terms of number of fruits plant-1 and fruit yield per plant were found to be significant during the years 2007 to 2009. During all the years of study, pruning treatments improved fruit yield and a pronounced effect was seen with pruning of third-order branches 30cm from their point of origin. Although difference in fruit yield among 30 and 45cm pruning treatment was not much and at par among the treatment. In case of pruning third order branches 30cm from origin the fruit yield was almost double compared to no pruning treatment (control). Mean cumulative fruit yield was higher for pruning treatments of 30 and 45cm. Similar result of increased fruit yield was reported by Lal and Mishra (2007, 2008) in mango cvs. Chausa and Dashehari, respectively. Rao and Shanmugavelu (1975, 1976), Rao and Khader (1979) and Shanmugavelu and Selvaraj (1985) also reported increased yield of mango growing to the redistribution of the endogenous normonal substances to favour flowering and fruiting in different varieties. Fruit yield in seven cultivars improved with pruning (Anon., 1979). It appears that the apparently quiescent fruit-bearing buds were activated by pruning treatment owing to redistribution of the endogenous hormonal substances, to favour flowering and fruiting. Pooled fruit yield data for four years showed increased fruit yield by pruning 30 and 45cm away third- order branches from point of origin. Fruit quality attributes: Fruit quality attributes such as average fruit weight, TSS, acidity and shelf-life as influenced by different pruning treatments are presented in Table 2. The average fruit weight during 2007 and 2008, TSS during 2008 and acidity during 2009 were found to be vary significantly among different pruning treatments. In general, pruning treatments reduced the fruit size due to a higher number of fruits plant-1. TSS, acidity and shelf-life were not affected by different treatments. Similar results were reported by Lal and Mishra (2008) in Dashehari mango. Table 1. Fruit yield of Alphonso mango as influenced by pruning Treatment No of fruits plant-1 Fruit yield plant-1 ( kg plant-1 ) 2006 2007 2008 2009 Cumulative Mean 2006 2007 2008 2009 Cumulative Mean T 1 -Pruning third order 273.6 596.7 235.6 400.4 1506.3 376.6 65.7 145.2 51.8 82.4 345.2 86.3 branches 30 cm from origin T 2 -Pruning third order 270.9 502.2 255.3 356.9 1385.3 346.3 67.7 121.5 54.1 72.5 315.8 78.9 branches 45 cm from origin T 3 -Contro(No Pruning) 206.3 190.0 186.2 211.1 793.6 198.4 49.5 48.4 46.9 44.2 189.0 47.2 F. test NS ** * ** * NS ** * ** * S.Em± 33.5 41.3 20.1 34.7 49.3 8.4 10.5 2.7 6.37 15.6 C.D. (P=0.05) __ 124.0 63.6 104.2 137.9 __ 31.4 8.5 19.1 46.8 C.D. (P=0.01) __ 170.9 __ 140.8 __ __ 48.3 __ 26.4 __ Reddy and Kurian NS = Non-significant, ** = Significant at P0.01 and * = Significant at P0.05 J. Hortl. Sci. Vol. 6(2):145-147, 2011 Prinect Color Editor Page is color controlled with Prinect Color Editor 4.0.70 Copyright 2008 Heidelberger Druckmaschinen AG http://www.heidelberg.com You can view actual document colors and color spaces, with the free Color Editor (Viewer), a Plug-In from the Prinect PDF Toolbox. Please request a PDF Toolbox CD from your local Heidelberg office in order to install it on your computer. 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REFERENCES Anonymous, 1979. Mango Workers’ Meeting, Panaji, Goa, 2-5 May, 1979. Research report on mango. pp357 Burondakar, M.M., Gunjate, R.T., and Magdum, M.B. 1997. Rejuvenation of old and overcrowded Alphonso mango orchards with pruning and use of paclobutrazol. Acta Hort., 409:209-210 Gross, E.R. 1997. Pruning mango to increase yield. Acta Hort., 455:538-542 Lakso, A.N. 1980. Aspects of canopy photosynthesis and productivity in the apple tree. Acta Hort., 114:100- 109 Lal, B., Rajput, M.S., Rajan, S. and Rathore, D.S. 2001. Effect of pruning on rejuvenation of old mango trees. Ind. J. Hort., 57:240-242 Lal, B. and Mishra, D. 2007. Effect of pruning on growth and bearing behaviour of mango cv. Chausa. Ind. J. Hort., 64:268-270 Lal, B. and Mishra, D. 2008. Studies on pruning in mango for rejuvenation. Ind. J. Hort., 65:405-408 National Horticultural Board. 2009. Database of Horticultural crops 2009 gurgaon, India Panse, V.G. and Sukhatme, P.V. 1985. Statistical Methods for Agricultural Workers. Fourth edition, ICAR, New Delhi Table 2. Fruit quality of Alphonso mango as influenced by pruning Treatment Average fruit weight (g) TSS (0Brix) Acidity (%) Shelf life (Days) 2006 2007 2008 2009 Mean 2006 2007 2008 2009 Mean 2006 2007 2008 2009 Mean 2006 2007 2008 2009 Mean T 1 - Pruning 241.5 243.9 220.3 206.1 227.9 17.5 17.0 18.0 16.9 17.3 0.201 0.268 0.202 0.201 0.218 13.2 12.5 13.2 12.9 12.9 third order branches 30 cm from origin T 2 - Pruning 250.2 242.3 213.7 205.9 228.0 17.0 17.9 18.2 16.8 17.5 0.268 0.268 0.201 0.268 0.251 13.5 13.0 13.5 13.5 13.3 third order branches 45 cm from origin T 3 -Control 245.7 256.1 253.3 210.4 241.4 16.5 17.2 17.1 17.0 16.9 0.268 0.201 0.268 0.201 0.234 13.0 13.0 13.0 13.2 13.0 (No Pruning) F. test NS * * NS NS NS * NS NS NS NS * NS NS NS NS S.Em± 3.9 2.5 1.9 3.3 1.2 0.9 0.3 0.5 0.4 0.2 0.5 0.02 0.6 1.0 0.4 0.3 C.D. (P=0.05) __ 7.5 5.7 __ __ __ 0.9 __ __ __ __ 0.06 __ __ __ __ Ranganna, S. 1986. Handbook of analysis and quality control for fruit and vegetable products Second edition, Tata McGraw Hill Publication Co. Ltd., New Delhi Rao, V.N.M. 1971. A note on pruning as a remedy for irregular bearing mango. Andhra Agri. J., 16: 242-245 Rao, V.N.M. and Shanmugavelu, K.G. 1976. Studies on the effect of pruning in mango. Prog. Hort., 8:21-28 Rao, V.N.M. and Shanmugavelu, K.G. 1975. Pruning – A new technique for mango growers. Agri. Agro. Industries J., September. pp 5-7. Rao, V.N.M. and Khader Abdul, J.B.M. Md. 1979. More about mango pruning. Ind. Hort., 25:135. Shanmugavelu, K.G. and Selvarajan, M. 1985. Studies on the effect of pruning on certain varieties of mango. Second Int’l. Symp. Mango (Abstract) p37 Schaffer, B. and Gauye G.O. 1989. Effects of pruning on light penetration, specific leaf density and chlorophyll content of mango. Sci. Hort., 41:55-61 Shinde, A.K., Patil, B.P., Pujari K.H. and Godse S.K. 2003. Pruning management in Alphonso mango for sustainability of fruit yield. Ind. J. Agril. Sci., 73: 641-644 Whitey, A.W. 1984. Crop management – A review. Proceedings of the First Australian Mango Research Workshop, Cairns, Queensland and CSIRO, Melbourne, pp196-201 (MS Received 28 September 2010, Revised 13 June 2011) Rejuvenation of old, unproductive mango trees NS = Non-significant, ** = Significant at P0.01 and * = Significant at P0.05 J. Hortl. Sci. Vol. 6(2):145-147, 2011 Prinect Color Editor Page is color controlled with Prinect Color Editor 4.0.70 Copyright 2008 Heidelberger Druckmaschinen AG http://www.heidelberg.com You can view actual document colors and color spaces, with the free Color Editor (Viewer), a Plug-In from the Prinect PDF Toolbox. Please request a PDF Toolbox CD from your local Heidelberg office in order to install it on your computer. 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