Study on phenology of mango (Mangifera indica L.) commercial varieties of coastal Andhra Pradesh

Introduction

Mango (Mangifera indica L.) belongs to family Anacardieceae is one of the most important tropical and subtropical fruit crops grown in India. Mango is popularly known as 'King of Fruits' due to its excellent flavour, attractive colour, delicious taste, huge variability and varied end usage. In Andhra Pradesh Mango is the most important fruit crop grown in 1.31 lakh hectare area and producing 43.5 lakh metric tonnes (Anonymous, 2023) [1] . Phenology is the study of periodic events in biological life cycles which are influenced by seasonal variations in climate. It depends on the environmental factors and the adaption capacity of the plants to a particular environment. It helps to understand the influence of weather dynamics on vegetative and reproductive growth period and also helps in adopting better crop management practices such as pruning, water and nutrient management, better integrated pest and disease management. Flowering is a decisive factor in the productivity of mango and is more or less a varietal character but mainly influenced by weather conditions. (Davenport, 2003) [2] observed that the flowering pattern of mango cultivars expresses differentially under tropical and subtropical conditions . The process associated with mango flowering involves shoot initiation followed by floral differentiation, and panicle emergence (Murti and Upreti, 2000) [3] . All these developmental events occur in most of the mango cultivars during October-December under tropical as well as subtropical conditions. Mango flowering is greatly influenced by the weather conditions and varietal genotypes and is most important traits as it directly affects the yield (Khushboo et al., 2018) [4] . The information on the phenological behaviour of commercial varieties of Coastal Andhra Pradesh was limited, hence this study was under taken to know the phenological behaviour of commercial varieties of Mango under Coastal Andhra Pradesh .

Methodol ogy

The present investigation was taken up at College of Horticulture, Venkataramannagudem, Dr. YSR Horticiltural university, West Godavari District, Andhra Pradesh. The experimental site falls under 'Agro-climatic Zone-10, humid, East Coast Plain and Hills'(Krishna-Godavari Zone) with an average annual rainfall of 900 mm at an altitude of 34 m (112 feet) above the mean sea level. It was geographically suited at 16º 63' 120" latitude and 81º 27' 568" East longitudes with hot humid summer and mild winter climate. The experiment was laid out in randomised block design (RBD) with four replications. Two trees were selected for each replication under each treatment. For recording all the observations sixty shoots were tagged in four direction (E,W,N&S) and the observations were made on daily basis. The observations were recorded on flowering characteristics viz., Days to panicle emergence from flower bud differentiation, Length of panicle by using measuring scale, Days to 50% flowering from panicle emergence, Days to full bloom, Days to first fruit set from panicle emergence by counting the days taken from panicle emergence, Number of hermaphrodite flowers, Number of male flowers, Total number of flowers which was counted physically at full bloom stage, Sex ratio, Flowering intensity(%), Average number of flowers set/ panicle, Days to marble stage from first fruit set, Days to maturity stage from first fruit set. Sex ratio was calculated by dividing number of male flowers with number of hermaphrodite flowers by using following formula.

Sex ratio = 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑚𝑎𝑙𝑒 𝑓𝑙𝑜𝑤𝑒𝑟𝑠 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 ℎ𝑒𝑟𝑚𝑎𝑝ℎ𝑟𝑜𝑑𝑖𝑡𝑒 𝑓𝑙𝑜𝑤𝑒𝑟𝑠

Reproductive shoots per square meter area under four directions were counted and the flowering intensity was worked out with the following formula.

Flowering intensity (%) = 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑓𝑙𝑜𝑤𝑒𝑟𝑖𝑛𝑔 𝑠ℎ𝑜𝑜𝑡𝑠 𝑇𝑜𝑡𝑎𝑙 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠ℎ𝑜𝑜𝑡𝑠

Statistical analysis

The data recorded on various parameters during the experiment were subjected to statistical analysis and the mean values have been summarized as per Panse & Sukhatme (1985) [5] and presented in various tables along with graphs and photographs .

Results and Discussion

The results based on statistical analysis were presented in The difference observed for the above characters among the varieties studied might be attributed to genetic architecture and gene x environment interaction effect. In addition to this, the temperature and maturity of shoot have more significant role in determining the panicle initiation and flowering duration. These results were in line with findings of Singh et al. (2014) [6] and Singh (2002) [7] in Mango.

The results from the ). Sex ratio (male to hermaphrodite flowers) was highest (4.9) in Cherukurasam and lowest (2.5) in Suvarnarekha. Flowering intensity (%) was found to be highest (63.7%) in Peddarasam which was on par with Cherukurasam (61.4%) while lowest flowering intensity was recorded in Chinnarasam (32.0%). Among the different commercial varieties, highest number of flowers set into fruits/ panicle were observed in Cherukurasam (8.8) which was on par with Suvarnarekha (8.7) and Himampasand (7.9) whereas in Chinnarasam the number of flowers set into fruits was low (5.7). The variation in panicle length among the varieties might be due to the genetic constitution of the cultivars and their interaction with the environmental conditions and more specifically the physiological conditions of shoot on which panicle is raised (Indian et al., 2020) [8] . The variation in sex ratio might be due to physiological and environmental conditions (Davenport and Nunez-Elisea, 1997) [9] . The difference observed for number of hermaphrodite, male and total flowers per panicle may be due to inherent genetic differences of different Mango varieties (Hada and Singh, 2017) [10] . The variation in flowering intensity may be due to genetic make up of the parental mango genotype (Kumar et al., 2010) [11] .

The results based on statistical analysis were presented in Figure 1 to 11

Conclusion

From the above results it can be concluded that Cherukurasam variety of Mango was found to be early in terms of days to 50% flowering, days to full bloom, days to marble stage and days to maturity stage fruits and Suvarnarekha was performed better in terms of sex ratio and fruit set under same set of environmental conditions in coastal Andhra Pradesh.

References

1. Davenport TL. Management of flowering in three tropical and subtropical fruit tree species. HortScience. 2003;38:1331-1335.
2. Murti GSR, Upreti KK. Changes in the level of endogenous hormones in relation to shoot vigour in mango (Mangifera indica L.). Plant Physiol Biochem. 2000;25(2):167-171.
3. Khushboo A, Hidayatullah M, Ravindra K, Feza A. Study on flowering behavior of elite mango cultivars in subtropical conditions of Bihar. Int J Chem Stud. 2018;6(2):2913-2917.
4. Singh A, Srivastav M, Singh AK, Dubey AK, Lal SK. Flowering attributes of parental mango genotypes. Indian J Hortic. 2014;71(4):458-463.
5. Singh S. Evaluation of mango cultivars for their flowering, fruiting and fruit quality attributes. Prog Hortic. 2002;34:240-243.
6. Indian G, Naik E, Deenavarman M, Jagathesan K, Janani T. Studies on the growth and flowering behaviour of different mango (Mangifera indica L.) genotypes. Int J Curr Microbiol App Sci. 2020;9(6):1981-89.
7. Davenport TL, Nunez-Elisea R. Reproductive physiology. In: Litz RE, editor. The Mango: Botany, Production and Uses. Wallingford, UK: CAB International; 1997. p. 69-146.
8. Hada TS, Singh AK. Evaluation of mango (Mangifera indica L.) cultivars for flowering, fruiting and yield attributes. Int J Bioresour Stress Manag. 2017;8(4):505509.
9. Kumar R, Kant K, Kumar S. Morphological characterization of some leading mango (Mangifera indica L.) cultivars in Bihar condition. Prog Res -Int J. 2010;5:493-497.