Final SPH -JHS Coverpage 17-1 Jan 2022 single J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 This is an open access article d istributed under the terms of Creative Commons Attribution-NonCommer cial-ShareAl ike 4.0 International License, which permits unrestricted non-commercial use, d istribution, and reproduction in any med ium, provide d the original author and source are credited. Original Research Paper INTRODUCTION Litchi (Litchi chinensis Sonn.), belonging to the family Sapindaceae is an evergreen, subtropical fr uit and popula r ly known a s ‘Queen of sub- tropical fruits’, ‘Pearl of India’ for its excellent aromatic flavour and sweet aril taste (Nakasone and Paull, 1998). Litchi flowers are of three types, st a mina t e or pu r ely ma le f lower s, f ema le or her ma p hr od it e f u nc t ioning a s f ema le a nd her ma phr odite flower functioning a s ma le or pseudo-hermaphrodite (Chaudari, 1940, Mustard et al., 1953 and Menzel, 1984). Litchi is very specific to its climatic requirement and requires seasonal temper a tur e va r ia tion for best flower ing a nd fruiting (Garcia-Perez and Martins, 2006). It is considered as the essential sub-tropical fruit crops and requires diurnal variation for flowering and fruiting. Litchi cultivation is successful in areas having average minimum temperature of 10oC from December to February and 32oC in April to June is considered more congenial. Climate is the most important limiting factor in the expansion of area under this fruit. The role of growing degree days (GDD) or heat units are often used to predict the growth stages including the date when a flower will bloom or a crop will reach to the maturity. Heat units or growing degree days is the number of temperature degrees above a certain threshold base temperature within consecutive 24 hours period. The heat unit varies among the crops or even within cultivars of the same crop (Kanzaria et al., 2015). Heat units have an important role in horticultural crops and it helps in estimating the growth stages of plants, deter mines ha rvesting index. It also assesses the suitability of a region for growing a crop to estimate the length of various phenological s t a ges a nd t o p r edic t ma t u r it y a nd qu a lit y c ha r a ct er is tics of f r u it s (K ha n et a l. , 20 07 ; Shinohara, 2013; Koshita, 2014). The effect of temper a tur e on the phenological development, flowering and fruiting performance was studied by the different workers for predicting the growth stages, yield and physiological maturity (Swan et al.,1989, Singh et al., 2007). The prevailing agro- climatic condition in the sub-Hima la ya n Tera i region is suitable for litchi cultivation. However, the information regarding the influence of heat units on flower bud development, panicle emergence, flowering and fruiting characteristics of litchi is very limited in literature. Keeping in view the utmost importance of heat units, the present study was designed to determine the effect of heat units and performance of different litchi cultivars in the foothills of eastern Indian sub-Himalayan Terai region of West Bengal. Heat unit requirement and performances of litchi under Sub-Himalayan terai region of West Bengal Subba S. and Bhowmick N.* Department. of Pomology and Post-Harvest Technology Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal-736165, India *Corresponding author E-mail : nilesh@ubkv.ac.in ABSTRACT To determine the heat unit requirement and assess its subsequent effects on flowering and fruiting characteristics, a field experiment was conducted during 2018-19 with seven cultivars of litchi viz., Calcuttia, Elaichi, Bedana, Bombai, China, Shahi and Muzaffarpur in randomized block design. Bedana showed better result in terms of maximum fruit weight (17.88g), lowest seed content (10.84%), maximum fruit diameter (3.01 cm), maximum fruit volume (18.70 ml), highest TSS (15.870 Brix), total sugar (15.96%), reducing sugar (12.61%), and ascorbic acid (29.47 mg/100g) content. Keywords: Bud break, flowering, fruiting, growing degree days and panicle. 125 Heat unit requirement and performances of litchi J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 MATERIALS AND METHODS To determine the heat unit requirement and assess its subsequent effects on flowering and fruiting cha r a c ter ist ic s of litc hi, the ex per iment wa s conducted at Instructional Farm under the Dept. of Pomology and Post-Ha rvest Technology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, situated in the foothills of ea s t er n I nd ia n H ima la ya s . S even imp or t a nt commercial litchi cultivars (T 1- Calcuttia, T 2 – Elaichi, T3 – Bedana, T4- Bombai, T5- China, T6- Sha hi a nd T 7- Muza ffa r pur ) wer e selected a s treatments and the experiment was carried out in randomized block design with three replication and two plants per replication. Heat unit was calculated by taking the average of the daily maximum and minimu m t e mp er a t u r es c omp a r ed t o a b a s e temperature, T base (usually 10°C). The formula applied for calculation of heat unit is (T max+Tmin)/ 2- Tbase(Monteith, 1984; Rai et al., 2002). The heat unit s for diff er ent p honologic a l pha ses wer e recorded. The different parameters for flowering and fruiting characteristics were recorded as per the standard methodology. The bio-chemical parameters were determined following Ranganna (1986) and A.O.A. C. (1984). For statistical analysis the mean separation for different parameter were performed using Least Significant Difference (LSD) test (Pd” 0.05).Normality of residuals under the assumption of ANOVA was tested using Kolmogrov-Smirnov, Shapiro-Wilk, Cramer-Von Mises and Anderson Darling procedure using Proc-Univariate procedure of SAS (version 9.3). RESULTS AND DISCUSSION Response of heat unit requirement on flowering of litchi The heat unit requirement of different phenological phases in litchi cultivars were recorded (Table-1). The heat unit requirement for bud break to panicle appearance was maximum in cv. China (144.03oC), which was statistically at par with cvs. Bombai, Calcuttia, Shahi and lowest in Elaichi (94.580C). Subsequently, it was observed (Table-2a) that cv. Bombai required maximum number of days (17.83 da ys ) f or b u d b r ea k t o p a nic le emer genc e, statistically at par with cv. China (17.27 days), while the cv. Elaichi recorded the minimum number of days (12.47 days). For panicle appearance to flowering, the heat unit requirement was maximum in cv. Bombai (400.16oC) which was statistically a t pa r with cvs. Ela ic hi (37 1. 3 1 o C), Beda na (340.20oC), Muzaffarpur (335.26oC) and Calcuttia (329.24oC), whereas, cv. Shahi required lowest (312. 38 o C) heat unit (Ta ble-1). However, the duration of panicle emergence was not significant a mong t he diff er ent cu ltiva r s (Ta ble- 2a ) b ut ma x imum nu mb er of da ys (3 5. 1 0 da ys ) wa s required in cv. Elaichi and lowest (29.52 days) in cv. Sha hi. T her e wa s no s ignifica nt va r ia tion observed during flowering to fruit set stage for heat u nit r eq u ir ement , howev er, it wa s r e c or ded ma ximum in cv. Muza ffa r pur (347.78 o C) a nd minimum (326.83oC) in cv. Calcuttia. The duration of flowering to fruit set was recorded maximum in c v. M u z a ff a r p u r ( 2 8 . 9 8 da ys ) whic h wa s statistically at par with all other cultivars except for cv. Bombai (23.95 days). The litchi varieties ex hibited signif ica nt va r ia tion f or hea t units requirement during fruit set to harvesting stages and cv. Beda na r egister ed the ma ximum hea t unit requirement (1133.80OC) which was at par with cv. China (1076.33 OC), whereas, the cv. Shahi required the minimum (950.74oC). Flowering parameters It is believed that litchi needs a period of vegetative dormancy to initiate floral buds (Das et al., 2004). The maximum length of panicle (19.00 cm) was observed incv. Muzaffarpur, while the minimum length (16.16 cm) was recorded in cv.Bedana.The flowering duration was statistically similar for different cultivars and cv. Muzaffarpur exhibited the maximum flowering duration (25.83 days).The ma ximum number of flower s per pa nicle wa s produced by the cv. Shahi (593.87) while it was minimum for cv. Bombai (422.80). Number of hermaphrodite flowers as functional male showed significa nt va ria tion and r a nged fr om 59. 19% (Bomabi) to 67.18 %(Muzaffarpur). The highest percentage of hermaphrodite flowers as functional female (21.26%) was recorded in the cv. Bombai while China r ecor ded t he lowes t p er c enta ge (17.94%) of hermaphrodite flowers as functional female. Bedana recorded the highest percentage of male flowers (19.60%) and Muzaffarpur registered the lowest percentage of male flowers (14.46%) (Table 2b). 126 Subba and Bhowmick Table 1. Heat unit requirement by different litchi cultivars Bud break to Panicle Flowering Fruit set to Treatments panicle appearance appearance to to fruit set harvesting (oC) flowering (oC) (oC) (oC) T1 (Calcuttia) 128.72 abc 329.24ab 326.83a 1012.48b T2 (Elaichi) 94.58 c 371.31ab 329.67a 957.37b T3 (Bedana) 104.50 bc 340.20ab 334.68a 1133.80a T4 (Bombai) 136.85 ab 400.16a 336.35a 1010.06b T5 (China) 144.03 a 322.33b 347.08a 1076.33a T6 (Shahi) 121.44 abc 312.38c 347.72a 950.74b T7 (Muzaffarpur) 100.24 c 335.26ab 347.78a 962.54b S.Em. (±) 11.80 23.94 10.54 20.41 L.S.D (Pd”0.05) 36.35 73.77 NS 62.90 Means followed by same alphabet are not significantly different Treatments Total no of Hermaphrodite Hermaphrodite Male flowers per panicle male (%) female (%) (%) T1 (Calcuttia) 476.52 cd 64.41a 19.67(4.43)ab 15.84(3.98)bcd T2 (Elaichi) 457.35 de 65.70a 18.33(4.28)ab 17.20(4.15)abcd T3 (Bedana) 518.92 bc 59.64b 20.09(4.47)ab 19.60(4.42)a T4 (Bombai) 422.80 e 59.19b 21.26(4.61)a 18.11(4.24)abc T5 (China) 528.83 b 63.67a 17.94(4.23)b 18.96(4.35)ab T6 (Shahi) 593.87 a 64.83a 19.52(4.42)ab 15.56(3.93)cd T7 (Muzaffarpur) 593.83 a 67.18a 18.48(4.30)ab 14.46(3.80)d S.Em.(±) 16.97 1.30 0.12 0.12 L.S.D (Pd”0.05) 52.03 4.01 0.36 0.38 Means followed by same alphabet are not significantly different (Value in parenthesis is the square root transformed value) Table 2b. Flowering parameters of different litchi cultivars Table 2a. Flowering parameters of different litchi cultivars Days taken for Duration of Length of Duration of Treatments bud break to panicle panicle flowering panicle emergence emergence (days) (cm) (days) T1 (Calcuttia) 12.67 c 29.55a 17.42bc 24.48a T2 (Elaichi) 12.47 c 35.10a 16.69cd 24.12a T3 (Bedana) 14.83 bc 30.20a 16.16d 23.58a T4 (Bombai) 17.83 a 31.47a 17.99ab 22.90a T5 (China) 17.27 ab 29.55a 16.39cd 24.13a T6 (Shahi) 13.95 c 29.52a 17.32bcd 25.38a T7 (Muzaffarpur) 13.65 c 30.02a 19.00a 25.83a S.Em.(±) 0.84 2.41 0.40 1.21 L.S.D (Pd”0.05) 2.59 NS 1.23 NS Means followed by same alphabet are not significantly different J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 127 Fruiting characteristics Duration of fruit set, fruit set percentage and fruits per panicle was statistically similar for all the cultivars under study. Calcuttia variety showed the maximum duration (11.97 days) for fruit set and was observed minimum in cv. Bombai (10.68 days). T he fr u it set p er c ent a ge va r ied f r om 3 . 41 % (Mu za ffa r p ur ) t o 4 . 7 9% (Bomb a i), wher ea s , number of fruits per panicle was observed from 18.08 (Bedana) to 23.22 (Shahi). Physio-chemical properties of fruits were significantly varied among the different cultivars studied under this experiment. H igher fr u it weight ( 17 . 8 8 g) , fr uit dia meter (3.01cm) and fruit volume (18.70ml) were observed in cv. Bedana. Small fruit of litchi was observed in cv. China (11.23g). The maximum fruit length (3.17 cm) was observed in cv. Bombai; however, the higher peel content (29.94%) and seed content (27.90%) makes the variety with high waste index (1.51). The fruit pulp content was highest in cv. Muzaffarpur (62.09%) and it was statistically at par with cvs. Calcuttia, Elaichi, Bedana and Shahi. Seed content was lowest in cv. Bedana (10.84%). The seed size (30.65%) and peel content (28.50%) were higher in cv. China resulting maximum waste index (1.66g) among the different varieties studied under this experiment. The minimum fruit length (2.71 cm) was recorded in Bedana. The data on fr uit diameter showed tha t the ma ximum fr uit dia meter (3. 01 c m) wa s r ec or ded in Beda na , whereas, Muzaffarpur recorded the minimum fruit diameter (2.33 cm). The maximum specific gravity (1.07) was observed in Elaichi while the minimum specific gra vity (0. 84) wa s recorded in Shahi. Highest pulp content (62.09%), and lowest waste index (0.64g) was recorded in Muzaffarpur. China recorded the maximum waste index (1.66g), seed c ont ent ( 3 0 . 6 5 % ) . P er c ent a ge o f ju ic e wa s ma ximum (55. 08%) in Sha hi while ma ximum peel (29.94%), minimum juice (30.03%) and was recorded in Bombai (Table 4b). Bio-chemical characteristics Litchi cv. Bedana was recorded with maximum total soluble solids (TSS) content (15.87 OBrix), total sugar content (15.96%), reducing sugar (12.61%) a nd a s c or b ic a c id content ( 29 . 47 mg/ 10 0 g) , whereas, cvs. Elaichi, China, Muzaffarpur, and Shahi recorded with lowest amount of TSS (13.930 Brix) and total sugar (11.45%), reducing sugar (9. 68 %), a nd a s cor b ic a cid (19. 72 mg/10 0g) content, respectively (Table 5). There was a variation among the litchi cultivars for different parameters studied under this experiment which indicates the genotypic differences. Higher heat unit requirement of cv. Bedana and China for fruit set to harvesting indicates it late maturity in Heat unit requirement and performances of litchi J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 Table 3. Fruiting characteristics of different litchi cultivars Date of Duration of Duration of Percent Fruits Treatments first fruit flowering to fruit setting fruit set per setting fruit set (days) (days) (%) panicle T1 (Calcuttia) 22 nd March 27.08ab 11.97a 4.25 (2.06)a 19.83a T2 (Elaichi) 22 nd March 26.77ab 11.53a 4.29 (2.06)a 19.03a T3 (Bedana) 26 th March 26.58ab 11.02a 3.56 (1.88)a 18.08a T4 (Bombai) 2 nd April 23.95b 10.68a 4.79 (2.18)a 19.83a T5 (China) 25 th March 27.55ab 11.17a 3.86 (1.97)a 20.27a T6 (Shahi) 23 rd March 28.90a 11.57a 3.85 (1.95)a 23.22a T7(Muzaffarpur) 22 nd March 28.98a 11.90a 3.41 (1.85)a 19.75a S.Em.(±) —- 1.24 0.45 0.11 2.29 L.S.D (Pd”0.05) —- 3.83 N.S. N.S. N.S. Means followed by same alphabet are not significantly different (Value in parenthesis is the square root transformed value) 128 Table 4a. Physical characteristics of fruits of different litchi cultivars Treatments Fruit Fruit Fruit Fruit Specific weight (g) length (cm) diameter (cm) volume (ml) gravity T1 (Calcuttia) 17.30 ab 3.14ab 2.70b 17.63ab 0.99ab T2 (Elaichi) 13.85 bc 2.86bcd 2.43c 13.07c 1.07a T3 (Bedana) 17.88 a 2.71d 3.01a 18.70a 0.96abc T4 (Bombai) 13.32 c 3.17a 2.48bc 13.87c 0.97abc T5 (China) 11.23 c 3.06ab 2.35c 13.30c 0.87bc T6 (Shahi) 12.43 c 3.01abc 2.47bc 15.03bc 0.84c T7 (Muzaffarpur) 11.78 c 2.78cd 2.33c 13.70c 0.88bc S.Em.(±) 1.26 0.09 0.09 1.11 0.05 L.S.D (Pd”0.05) 3.89 0.27 0.26 3.43 0.14 Means with the same letter are not significantly different Table 4b. Physical composition and waste index of litchi fruits Treatments Juice (%) Peel (%) Pulp (%) Seed (%) Waste index (g) T1 (Calcuttia) 46.12 ab 17.80c 59.98a 22.22bc 0.79bc T2 (Elaichi) 44.48 b 22.16c 58.73a 19.11c 0.92bc T3 (Bedana) 44.11 b 29.82a 59.34a 10.84d 0.70bc T4 (Bombai) 30.03 c 29.94a 42.16b 27.90ab 1.51a T5 (China) 37.44 bc 28.50ab 40.85b 30.65a 1.66a T6 (Shahi) 55.08 a 23.14bc 52.84a 24.02bc 1.19ab T7(Muzaffarpur) 40.65 b 18.75c 62.09a 19.16c 0.64c S.Em.(±) 3.41 1.81 3.43 2.08 0.18 L.S.D (Pd”0.05) 10.50 5.58 10.57 6.42 0.54 Means followed by same alphabet are not significantly different Table 5. Biochemical properties of litchi fruits Treatments TSS Total Reducing Acidity TSS:acid Ascorbic acid (oBrix) sugar (%) sugar (%) (%) ratio (mg/100g) T1(Calcuttia) 14.63 bc 13.15abc 11.55b 0.42b 34.80bcd 23.83b T2 (Elaichi) 13.93 d 14.71ab 10.87c 0.42b 33.11cd 28.82a T3 (Bedana) 15.87 a 15.96a 12.61a 0.54a 29.86d 29.47a T4 (Bombai) 15.20 b 12.60bcd 12.41a 0.40b 38.36bc 20.37c T5 (China) 14.37 cd 11.45b 10.62cd 0.52a 27.89d 23.62b T6 (Shahi) 14.87 bc 12.30a 10.95cd 0.32c 47.41a 19.72c T7(Muzaffarpur) 14.80 bc 11.72b 9.68d 0.36bc 41.34ab 23.40b S.Em.(±) 0.21 0.17 1.02 0.03 2.50 0.40 L.S.D (Pd”0.05) 0.63 0.53 3.16 0.08 7.71 1.24 Means followed by same alphabet are not significantly different Subba and Bhowmick J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 129 this agro-climatic situation. The wide variation in heat unit may be due to the varied maturity period of different cultivars indicates that each genotype needs certain amounts of accumulation of heat units for completion of different phenopha ses which cause the variation in maturity period (Rai et al., 2003). Flowering span might be differed in case of climatic condition, but flowering span of particular variety is over only when the required heat units are accumulated (Byrne and Bacon, 1992). The flowering parameters result shows similar trends as obser ved by Baner jee a nd Cha udhar y (1944), Mustard et al (1953), Chadha and Rajpoot (1969), Pivovar o (1974) and Kuma r (2000). T he data indicated that the maximum titrable acidity (0.54%) was recorded in Bedana while the minimum titrable a c idit y c o nt ent ( 0 . 3 2 % ) wa s r ec or ded in Shahi.TSS:acid ratio was maximum (47.41) in Shahi and the minimum TSS:acid ratio (27.89) was recorded in China. The differences of fruit physio- chemica l p r oper ties indic a te t he r ela t ionship between cultivars and heat unit requirement. CONCLUSION There was a varietal difference regarding the heat unit requirements for different phonological phases r esult ing va r ia t ion on flower ing a nd fr uiting characteristics. Bedana required maximum heat unit (1133.80oC) for attaining the harvesting stage from fruiting cultivar and it was lowest in cv. Shahi (950.74oC). Litchi cv. Bedana exhibited promising results in terms of flowering, fruiting and quality pa r a meter s with r es pec t t o high fr u it weight (17.88g), fruit diameter (3.01cm), fruit volume (18.70 ml), TSS (15.87OBrix), total sugar content (1 5. 96 %) , r educ ing su ga r content ( 12 . 6 1% ), ascorbic acid content (29.47 mg/100g) and may be recommended as promising cultivar in terms of better-quality characters under the sub-Himalayan Terai region of West Bengal condition. ACKNOWLEDGEMENT Authors ar e thankful to the authority of Uttar Banga Krishi Viswavidyalaya for supporting to conduct the experiment. REFERENCES A. O. A. C. 1984. Official methods of analysis, 14th edition, Association of Official Agriculture Chemist, Washington, D.C. Banerjee, J. and Chaudhary, K.L. 1944.A contribution to the life history of Litchi chinensis Sonn. Proc. Indian Acad. Sect, 19:19-27. Byrne, D.H. and Bacon, T. 1992. Chilling estimation: its impor ta nce a nd estima tion. Texas Horticulturist, 18(8-5): 8–9. Chaudari, J.K. 1940. A note on the morphology and chromosome number of Litchi chinensis Sonn. Current Science, 9: 416. Chadha, K.L. and Rajpoot, M.S. 1969. Studies on floral biology, fruit set, and its retention and quality of some litchi varieties. Indian Journal of Horticulture, 26: 129-4. Da s, B. , Na th, V. , Ra i, M. a nd Dey, P. 2004.Investigation on flushing and panicle emergence in litchi under sub-humid subtropical plateau region of eastern India. Journal of Horticulture, 61: 1- 5. Ga r c ia -P er ez , E. a nd M a r tins , A. B. G. 2 00 6. Flowering and fruiting lychee trees due to the girdling branches. Journal of Fruit Growing, 28(1): 14–7. Kanzaria, D., Chovatia, R., Polara, N., Varu, D. 2015.Impact of GDD on phenology of mango (M an gi fe ra in di ca ) . I nd ia n Jo u rn al o f Agricultural Sciences, 85 (8): 1114–1117 Khan, A.R., Ullah, H., Siddique, I. M. and Hafeez, M. 2007. Ecological nexus for the qualitative production of citrus fruits. Proceedings of the international symposium on prospectus of horticultural industry in Pakistan, Institute of H or t ic u lt u r a l S c ienc es , Univ er s it y of Agriculture, Faisalabad, Pakistan, pp 83–86. Koshita, Y. 2014. Effect of temperature on fruit color development. In: Yoshinori Kanayama and Alexey Kochetov. Abiotic Stress Biology in Horticultural Plants. Springer, Japan, pp 44–58. Heat unit requirement and performances of litchi J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 130 Subba and Bhowmick J. Hortl. Sci. Vol. 17(1) : 124-130, 2022 Kumar, A. 2000. Effect of foliar spray of multi-K on yield, quality and shelf life of litchi (Litchi chinensis Sonn.) cv. Rose Scented. Thesis, M . S c . Ag. ( H or t ic u lt u r e) , G. B. P a nt University of Agriculture and Technology, Pant Nagar. M u s t a r d, M. J . , L iu , S . Y. a nd Nels on, R . O . 1953.Observa tions of flor al biology and fruit- setting in Lychee varieties. Proceedings of Florida. State Horticulture Society, 66: 212-20. Menzel, C.M. (1984): The pattern and control of reproductive development in lychee. A review Sci. Hort., 22(4): 333-345. Monteith, J.L. 1984. Consistency and convenience in the choice of units for agriculture science. Exptl Agric., 20: 105-117 Nakasone, H.K. and Paull, R.E. 1998. Tropical Fr u i t s . p p 4 4 5 . C AB I nt er na t iona l, Wallingford UK Pivovaro, S.Z. 1974. Studies on the floral biology and the influence of growth regulators on fruit set, size and drop of Litchi chinensis Sonn. Thesis, M.Sc. Ag., Hebrew University of Rehovot, pp39 Rai, M., Nath, V. and Das, B. 2002. Heat unit summa tion- an index for predicting fruit maturity in litchi (Litchi chinensis Sonn.). Indian J. Hort., 59 (1): 34-38. Ranganna, S. 1986. Handbook of a nalysis and qua lity cont r ol f or f r uit a nd veget a ble p r odu c t s ( 2 n d ed) Ta t a M c G r a w H ill Publishing Company Ltd New Delhi. Shinohara, T. Usui, M., Higa, Y., Igarashi, D. and I nou e, T. 20 1 3. Eff ec t of a c cu mula ted minimum temperature on sugar and organic acid content in passion fruit. Journal of International Society for Southeast Asian Agricultural Sciences,19: 1–7. Singh, I. A., Rao, U. V. M., Singh, D. and Singh, R. 20 07. St udy on a gr o- met eor ologic a l indices for soybean crop under different gr owing envir onment. Jour nal of A gro- meteorology, 9:81-85 Swa n, J. B. , Schneider, E. C. , Moncr ief, J. E. , Pa ulson, W.H. and Peterson, A. E. 1989. Estima ting crop gr owth yields a nd gra in moistur e from gr owing degree da ys a nd residue cover. Agronomy Journal, 79:53-60. (Received: 28.10.202; Revised: 05.02.2022; Accepted: 05.02.2022) 00 A Final SPH -JHS Coverpage First 2 pages.pdf 00 Content and in this issue.pdf 01 Mohan Kumar G N.pdf 02 Meera Pandey.pdf 03 Biradar C.pdf 04 Varalakshmi B.pdf 05 Vijayakumari N.pdf 06 Barik S.pdf 07 Sajid M B.pdf 08 Ranga D.pdf 09 Usha S.pdf 10 Manisha.pdf 11 Amulya R N.pdf 12 Akshatha H J.pdf 13 Adak T.pdf 14 Sujatha S.pdf 15 Gowda P P.pdf 16 Subba S.pdf 17 Dhayalan V.pdf 19 Ahmed S.pdf 20 Vishwakarma P K.pdf 21 Deep Lata.pdf 22 Udaykumar K P.pdf 23 Nayaka V S K.pdf 24 Sahel N A.pdf 25 Bayogan E R V.pdf 26 Rathinakumari A C.pdf 27 Yella Swami C.pdf 28 Saidulu Y.pdf 29 Sindhu S.pdf 30 Neeraj.pdf 31 Sivaranjani R.pdf 32 Rashied Tetteh.pdf 34 Sangeetha G.pdf 35 Shareefa M.pdf 36 Last Pages.pdf