Effect of different training system on fruit yield and quality of pear (Pyrus communis L.)

Introduction

Pear (Pyrus communis L.) is an important temperate fruit after apple in the family Rosaceae. It is originated from China. Pears rank second only to apples in importance, production, and varietal diversity among temperate fruits. Pears are mildly sweet fruits with a fibrous centre. In India, pears hold the second position among temperate fruits in both area and production, cultivated on 44,000 hectares with an annual production of 318 metric tons (Anonymous, Pear ranks second after apples as the most frequently consumed and economically important tree fruit in temperate regions worldwide (Ahmed et al., 2011) [1] . In new plantations, initial training is provided to develop a strong framework for the tree, whereas in older plantations, the goal of canopy management is to reduce tree height and improve solar radiation penetration inside the canopy by thinning excessive biomass (Wani et al., 2021) [51] . Effective canopy management practices result in better sunlight penetration and improved yield. They enable profitable cropping, consistent high yields, and enhanced farm management, ultimately leading to increased productivity. This approach produces high-quality fruits with regular yields while reducing labor requirements, helping to control rising production costs. Plant canopy is the main driver for management of energy from sunlight to the sink organs particularly the fruits. Therefore, conversion of sunlight energy into fruits is the important task. There are a number of factors affecting the availability of sunlight and energy too is like location, climate and year. Training plays a significant role in obtaining regular and prolific quality fruit production. The size, colour, nutritional quality, and postharvest shelf life of fruits are all significantly affected by the training done during the pre-harvest stages in orchard (Sharma et al. 2018) [48] . Training begins at the nursery stage of the plant. The main goal of tree training is to encourage favorable growth patterns. Training helps bring trees into production earlier, develop a strong structural framework capable of supporting heavy crop loads without breaking, promote good sunlight penetration through the canopy, and make the trees easier to manage (Hassan et al., 2010) [13] . Training helps establish a strong framework of scaffold limbs capable of supporting heavy yields and high-quality fruits, ensures regular annual crop succession, maximizes leaf exposure to sunlight, and directs tree growth to make cultural operations such as spraying and harvesting more economical. Additionally, it protects the tree from sunburn and promotes early production (Kaith et al., 2011) [14] . In pear cultivation, training systems are a preferred choice for high-density planting compared to the use of dwarfing rootstocks or cultivars. Various training systems such as Open Vase, Espalier, Cardon, Palmette, Fuestoo, Free Spindle, and Y-Trellis are employed in pears to enhance fruit quality.

Materials and Methods

The experiment titled "Studies on canopy management on

Yield attributes  Number of fruits per tree

The number of fruits per tree was recorded by counting the fruits in each of the experimental tree and it was expressed in numbers.

The number of fruit set against number of flowers recorded in previous observation was counted and percent was calculated against total number fruit set on the tagged shoot. The length and breadth of 10 fruit samples from each treatment were measured using digital Vernier calipers and expressed in centimetres.

The weight of the sampled fruits was measured using a physical balance, and the average weight was expressed in grams per fruit.

 Fruit yield (kg tree -1 ) Fruit yield per tree was estimated by multiplying the total number of fruit per tree with average fruit weight and was expressed in kg per tree.

 Fruit yield (q ha -1 ) Fruit yield in quintal per hectare was estimated by multiplying the average fruit yield per tree with total number of plants per hectare.

Fruit yield (q ha -1 ) = Fruit yield (kg tree -1 ) x Number of plants (ha -1 )

Bio-Chemical attributes  Total soluble solids ( 0 Brix) Total soluble solids in ripened fruit were measured using an electronic hand refractometer (0-32 °Brix) by

placing one to two drops of juice on the prism. The refractometer was calibrated with distilled water before each use. The results were expressed in °Brix.

The sum of reducing and non-reducing sugars was expressed as total sugars.

𝑇𝑜𝑡𝑎𝑙 𝑠𝑢𝑔𝑎𝑟 (%) = 𝑅𝑒𝑑𝑢𝑐𝑖𝑛𝑔 𝑠𝑢𝑔𝑎𝑟 (%) + 𝑁𝑜𝑛 -𝑟𝑒𝑑𝑢𝑐𝑖𝑛𝑔 𝑠𝑢𝑔𝑎𝑟 (%)

The reducing sugar content was determined by the procedure given by Rangana (1986). Weighed 5g of fruit and macerated with a small amount of distilled water, filtered in a 100 mL volumetric flask and volume was maintained with distilled water up to 100mL. 5 ml sample was taken and 5 ml of Fehling Solution 'A' and 5 ml of Fehling Solution 'B' in each tube. The solution was titrated with 1 % of glucose solution and boiled.

The solution was checked by the methylene blue indicator and the endpoint was marked by the appearance of brick red color.

Reducing Sugar (%) = Blank titre value (ml)-Sample titre value(ml)X Vol.made up (ml)

Weight of the sample (g)X Weight of aliquat taken (ml)

The amount of non-reducing sugar was worked out by taking the difference between total sugars and reducing sugar.

(Total invert sugarsreducing sugar) x 0.95

The titratable acidity of macerated juice samples was determined by the visual titration method (AOAC, 1984) as briefed below:

Preparation of sample: Five ml of macerated juice was taken in a 250 ml conical flask, and the volume was made up to 100 ml with distilled water, and the colour was removed with the use of activated charcoal. Then an aliquot is used.

Procedure: Ten ml of an aliquot was taken in a conical flask and titrated against 0.1N NaOH solution using 1 or 2 drops of phenolphthalein indicator (pH 8.2 to 10.0). Formation of pink colour was reckoned as the endpoint of titration. Then, the titratable acidity was calculated as follows:

 Cost: Benefit ratio analysis

In order to find out benefit cost ratio, gross return of individual treatment per hectare was divided, by their respective cost of cultivation per hectare including fixed and treatment cost.

Results and Discussion

In present investigation, yield, quality and economics parameters includes number of fruit per tree, Fruit setting (%), fruit size (cm), fruit weight (gm), fruit yield (kg tree -1 ) fruit yield (q ha -1 ), Total soluble solids ( 0 Brix), Total sugar (%), Reducing sugar (%), Non-reducing sugar, Titrable Acidity (%) and Economics of treatments which was found significant among all the treatments as compare to control and presented in Table 1, 2& 3..

Yield Parameters 1.1 Number of fruits per tree

The maximum number of fruits per tree (42.36) was recorded in variety V1 (Baggugosha), which was significantly superior to the other treatments, while the minimum average (40.37) was observed in variety V3 (Punjab Gold). The training system had a significant impact on the number of fruits per tree. The highest average number of fruits per tree (45.42) was recorded under training system T3 (Espalier), whereas the lowest average (37.32) was found with T4 (Control). The interaction between training system and variety was also significant for the number of fruits per tree. The highest average number (46.53) was observed in the combination of Espalier training system with variety V1 (V1T3), while the lowest average (35.47) was recorded in the Control with variety V3 (V3T4). Similar findings have also been reported by Moniruzzaman et al. (2007) [25] , MA et al. (2012), Fisher and Orduz-Rodriguez (2012), Lawande et al. (2014) [18] and Goncalves et al. (2014) [10] .

The maximum fruit setting (17.47 %) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (16.50 %) was recorded with variety V3 (Punjab Gold).

Training system has the significant impact on fruit setting per cent. The average maximum fruit setting (18.70 %) was found to be significantly higher with T3 (Espalier). Whereas, the average minimum (15.62 %) was found to be lower with T4 (Control). The interaction impact of training system and variety for fruit setting per cent was found significant. The average maximum fruit setting (21.01 %) was found to be significantly higher with Espalier (V1T3). While, the average minimum fruit setting (14.43 %) was recorded with Control (V1T4). Similar results were also reported by several investigators such as Hassan et al. (2010) [13] , Mohamed, [10] , Sahoo et al. (2017) [47] and Lei et al., (2021) [21] .

The maximum fruit size (5.95 cm) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (5.70

cm) was recorded with variety V3 (Punjab Gold). Training system has the significant impact on fruit size. The average maximum fruit size (6.45 cm) was found to be significantly higher with T3 (Espalier). However, the average minimum (5.38 cm) was found to be lower with T4 (Control). The interaction impact of training system and variety for fruit size was found significant. The average maximum fruit size (6.77 cm) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum fruit size (5.25 cm) was recorded with Control (V3T4). Similar findings were also reported by Robinson et al. (2006) [31] , Moniruzzaman et al. (2007) [25] , MA et al. (2012), Sharma L. K. (2014) [40] , Goncalves et al. (2014) [10] and Lordan et al. (2017) [20] .

Fruit weight (gm)

The maximum fruit weight (156.42 gm) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (150.08 gm) was recorded with variety V3 (Punjab Gold).

Training system has the significant impact on fruit weight. The average maximum fruit weight (169.55 gm) was found to be significantly higher with T3 (Espalier). However, the average minimum (142.99 gm) was found to be lower with T4 (Control). The interaction impact of training system and variety for fruit weight was found significant. The average maximum fruit weight (177.03 gm) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum fruit weight (139.26 gm) was recorded with Control (V1T4). Similar results were also reported by Feng et al. (2014) [8] , Sharma, L. K. (2014) [40] , Dallabetta et al. (2014) [6] , Rutkowski et al., (2015) [38] , Sahoo et al.

(2017) [47] , Ranjit and Ghosh (2019) [28] and Kiramani, S. (2020) [16] .

The maximum Fruit yield (7.09 kg tree -1 ) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (6.44 kg tree -1 ) was recorded with variety V3 (Punjab Gold).

Training system has the significant impact on Fruit yield. The average maximum fruit yield (8.46 kg tree -1 ) was found to be significantly higher with T3 (Espalier). Whereas, the average minimum (5.49 kg tree -1 ) was found to be lower with T4 (Control). The interaction impact of training system and variety for fruit yield was found significant. The average maximum fruit yield (10.89 kg tree -1 ) was found to be significantly higher with Espalier (V1T3). While, the average minimum fruit yield (5.28 kg tree -1 ) was recorded with Control (V3T4). Similar results were also reported by several investigators such as Lu et al. (2003), Rufato et al.

(2004) [32] , Morgan (2005), Rivas (2008) [30] , Komaya et al.

(2012) and Lei et al. (2021) [21] .

The maximum Fruit yield (72.16 q ha -1 ) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (69.99 q ha -1 ) was recorded with variety V3 (Punjab Gold).

Training system has the significant impact on Fruit yield. The average maximum fruit yield (79.65 q ha -1 ) was found to be significantly higher with T3 (Espalier). However, the average minimum (62.99 q ha -1 ) was found to be lower with T4 (Control). The interaction impact of training system and variety for fruit yield per tree was found significant. The average maximum fruit yield (87.65 q ha -1 ) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum fruit yield (60.03 q ha -1 ) was recorded with Control (V3T4). Similar results were also reported by Sosna and Czaplicka (2008) [45] , Caruso et al. (2008) [3] , Kiprijanovski et al. (2009) [15] , Lavee et al. (2012) [19] , Ramirez and kallarackal (2015) [27] and Seki et al., (2018) [39] .

Bio-Chemical parameters 2.1 Total soluble solids ( 0 Brix)

The maximum Total soluble solids (13.69 0 Brix) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (12.82 0 Brix) was recorded with variety V3 (Punjab Gold). Training system has the significant impact on Total soluble sugar. The average maximum Total soluble solid (14.24 0 Brix) was found to be significantly higher with T3 (Espalier). However, the average minimum (12.81 0 Brix) was found to be lower with T4 (Control). The interaction impact of training system and variety for Total soluble solids ( 0 Brix) was found significant. The average maximum Total soluble solid (14.43 0 Brix) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum Total soluble solid (12.05 0 Brix) was recorded with Control (V2T4). Similar findings were reported by Ferina et al. (2005) [7] , Cortell and Kennedy (2006) [5] , Moniruzzaman et al. (2007) [25] , Ristic et al.

(2007) [36] , Nilsson and Gustavsson (2007) [26] , Sousa et al.

(2008) [46] , He et al. (2008) [12] , Feng et al. (2014) [8] , Goncalves et al. (2014) [10] , Sharma, L. K. (2014) [40] , Rahmani et al. (2015) [35] , Lordan et al. (2017) [20] , Ranjit and Ghosh (2019) [28] and Gill et al., (2021) [11] .

The maximum Total sugar (11.64 %) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (10.89 %) was recorded with variety V3 (Punjab Gold).

Training system has the significant impact on Total sugar per cent. The average maximum Total sugar (11.82 %) was found to be significantly higher with T3 (Espalier). Whereas, the average minimum (10.61 %) was found to be lower with T4 (Control). The interaction impact of training system and variety for Total sugar (%) was found significant. The average maximum Total sugar (12.43%) was found to be significantly higher with Espalier (V1T3). While, the average minimum Total sugar (9.51 %) was recorded with Control (V2T4). Similar findings were also reported by Singh, (2001) [43] , Cortell and Kennedy (2006) [5] , Li et al. (2006) [22] , Ristic et al. (2007) [36] , Rahmani et al. (2015) [35] , Sahoo et al. (2017) [47] and Ranjit and Ghosh (2019) [28] .

The maximum Reducing sugar (6.30%) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (6.15 %) was recorded with variety V3 (Punjab Gold). Training system has the significant impact on Reducing sugar per cent. The average maximum Reducing sugar (6.59 %) was found to be significantly higher with T3 (Espalier). However, the average minimum (5.49 %) was found to be lower with T4 (Control). The interaction impact of training system and variety for reducing sugar (%) was found significant. The average maximum Reducing sugar (6.95 %) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum Reducing sugar (5.32 %) was recorded with Control (V3T4). Similar results were also reported by several investigators such as Robinson et al. (1997) [37] and Singh and Chauhan (1998) [44] .

The maximum non-reducing sugar (5.08%) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (4.77 %) was recorded with variety V3 (Punjab Gold). Training system has the significant impact on nonreducing sugar. The average maximum non-reducing sugar (5.26%) was found to be significantly higher with T3 (Espalier). While, the average minimum (4.55%) was found to be lower with T4 (Control). The interaction impact of training system and variety for non-reducing sugar (%) was found significant. The average maximum non-reducing sugar (5.58 %) was found to be significantly higher with Espalier (V1T3). Whereas, the average minimum Nonreducing sugar (4.37%) was recorded with Control (V3T4). Similar findings were also reported by Rather, G. H. ( 2006) [33] , Kaith et al. (2011) [14] , Singh et al. (2012) [41] , Sharma, L. K. (2014) [40] and Marini, R. (2014) [23] .

The maximum Acidity (0.39 %) was recorded with variety V1 (Baggugosha) which was found significantly superior over the treatments and the average minimum (0.38 %) was recorded with variety V3 (Punjab Gold) and it was also at par with V2 (Punjab Beauty). Training system has the significant impact on Acidity per cent. The average maximum Acidity (0.45 %) was found to be significantly higher with T3 (Espalier). However, the average minimum (0.34 %) was found to be lower with T4 (Control). The interaction impact of training system and variety for Acidity (%) was found significant. The average maximum Acidity (0.47%) was found to be significantly higher with Espalier (V1T3). Moreover, the average minimum Acidity (0.34 %) was recorded with Control (V3T4) and it was also at par with Control (V2T4). Similar findings were also reported by Rathi et al. (2001) [34] , Choi et al. (2014) [4] , Rahmani et al. (2015) [35] , Mmoradiedigehsara et al. (2015) [24] , Rutkowski et al. (2015) [38] and Lordan et al. (2017) [20

A perusal of data presented in Table 4.4 and Figure 4.4 indicated that total cost of cultivation varied as variation in different treatments. The total cost of cultivation was recorded highest (163647.00 Rs./ha ) with the treatments T3 (Espalier system and Baggugosha variety), T7 (Espalier system and Punjab Beauty variety) and T11 (Espalier system and Punjab Gold variety). Whereas, the minimum (62922.00 Rs./ha) total cost of cultivation was recorded for the treatments T4 (Control), T8 (Control) and T12 (Control), respectively. Similar results were also reported by Tiwari and Lal (2007) [49] and Singh, G. (2010) [42] .

Data on grass return was calculated under different treatment. The maximum grass return (701200.00 Rs./ha) were obtained with the treatment T3 (Espalier system and Baggugosha variety). While, the lowest gross return (158730.00 Rs./ha) was recorded with the treatment T4 (Control).

Data presented in Table 4.4 revealed that the maximum net return (537553.00 Rs./ha) was recorded with the treatment T3 (Espalier system and Baggugosha variety). However, the minimum Net return (95808.00 Rs./ha) was obtained with the treatment T4 (Control).

Cost: Benefit ratio analysis

Data pertaining to costs benefit ratio shown in Table 4.4 revealed that the maximum cost: benefit ratio (1:4.28) was recorded with the treatment T3 (Espalier system and Baggugosha variety). Whereas, the minimum cost: benefit ratio (1:2.52) was obtained with the treatment T4 (Control).

Conclusion

Based on the above investigation, It can be concluded that the training system had a significant effect on pear yield, influencing parameters such as number of fruits per tree, fruit setting (%), fruit size (cm), fruit weight (g), fruit yield (kg tree⁻¹), fruit yield (q ha⁻¹), total soluble solids (°Brix), total sugar (%), reducing sugar (%), non-reducing sugar (%), acidity (%), and the economics of the treatments. The best results were observed with the Espalier training system using the Baggugosha variety. This combination is recommended for achieving higher pear yields under the conditions of western Uttar Pradesh.

Acknowledgement

AcknowledgmentI extend my sincere thanks to my advisor and committee members for their invaluable guidance throughout my course of study. I am also very grateful to the Department of Fruit Science, College of Horticulture and Forestry for their support, ANDUA & T, Ayodhya, Utter Pradesh, India

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