Browsing by Author "Amarnath, C.H."
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Item Coconut (Cocos nucifera L.) Pollen Cryopreservation(2014) Anitha Karun; Sajini, K.K.; Niral, V.; Amarnath, C.H.; Remya, P.; Rajesh, M.K.; Samsudeen, K.; Jerard, B.A.; Florent EngelmannBACKGROUND: Coconut genetic resources are threatened by pests and pathogens, naturalhazards and human activities. Cryopreservation is the only method allowing the safe and costeffectivelong-term conservation of recalcitrant seed species such as coconut. OBJECTIVE: The objective of this work was to test the effect of cryopreservation and of cryostorage duration on coconut pollen germination and fertility. MATERIALS AND METHODS: Pollen of two coconut varieties (West Coast Tall WCT and Chowghat Orange Dwarf COD ) was collected in March-May over three successive years, desiccated to 7.5% moisture content (FW) and cryopreserved by direct immersion in liquid nitrogen. RESULTS: Germination and pollen tube length (PTL) of desiccated and cryopreserved pollen were not significantly different for both WCT and COD over the three harvest months of the three consecutive years of study. Pollen germination ranged from 24 to 32% in desiccated pollen whereas it was between 26 and 29% in cryopreserved COD pollen. In the case of WCT, germination ranged from 30 to 31% in desiccated pollen, while it was between 28 and 32% in cryopreserved pollen. PTL of cryopreserved pollen ranged between 224-390 m and 226-396 m for COD and WCT, respectively. Germination of COD pollen varied between 29.0 and 44.1% after 4 years and 1.0/1.5 years cryostorage, respectively. Germination of WCT pollen did not change significantly between 0 and 6 years cryostorage, being comprised between 32 (24 h) and 40 % (1.5 years). Germination and vigour of cryopreserved pollen were generally higher compared to that of pollen dried in oven and non-cryopreserved. Normal seed set was observed in COD and WCT palms using pollen cryostored for 6 months and 4 years. Cryopreserved pollen of five Tall and five Dwarf accessions displayed 24-31% and 25-49% germination, respectively. CONCLUSION: These results show that it is now possible to establish pollen cryobanks to contribute to coconut germplasm long-term conservation.Item COCONUT(COCOS NUCIFERA L.)POLLEN CRYOPRESERVATION(2014) Anitha Karun; Sajini, K.K.; Niral, V.; Amarnath, C.H.; Remya, P.; Rajesh, M.K; Samsudeen, K; Jerard, A.; Florent EngelmannItem A complimentary conservation strategy for coconut (Cocos nucifera L.) through pollen cryopreservation(2012-11) Sajini, K.K.; Anitha Karun; Amarnath, C.H.; Rajesh, M.K.Item Cryopreservation of Coconut (Cocos Nucifera L.) Zygotic Embryos by Vitrification(2011) Sajini, K.K.; Anitha Karun; Amarnath, C.H.; Florent EngelmannThe present study investigates the effect of preculture conditions, vitrification and unloading solutions on survival and regeneration of coconut zygotic embryos after cryopreservation. Among the seven plant vitrification solutions tested, PVS3 was found to be the most effective for regeneration of cryopreserved embryos. The optimal protocol involved preculture of embryos for 3 days on medium with 0.6 M sucrose, PVS3 treatment for 16 h, rapid cooling and rewarming and unloading in 1.2 M sucrose liquid medium for 1.5 h. Under these conditions, 70-80% survival (corresponding to size enlargement and weight gain) was observed with cryopreserved embryos and 20-25% of the plants regenerated (showing normal shoot and root growth) from cryopreserved embryos were established in pots.Item Diversity of coconut accessions for fruit components(2005) Ratnambal, M.J.; Muralidharan, K.; Krishnan, M.; Amarnath, C.H.Using Mahalanobis generalized distance, 70 accessions of field conserved coconut germplasm maintained at Central Plantation Crops Research Institute, Kasaragod were classified for fruit characteristics. In the dendrogram showing hierarchical clustering, 4 the largest group consisted of 47 accessions. Amalgamation of clusters in this group was at shorter distance. Classification of the accessions into distinct groups was also attempted. The pattern of amalgamation observed in the dendrogram was taken as the guideline for deciding the cut-off points in the partition method which resulted in twenty seven clusters. The cluster size varied between 1 to 7: there were two clusters each of sizes 7 and 5; five clusters of size 4; eight clusters of size 2 and the remaining 12 were singletons. It was noticed that the popular cultivars known across the world (West ~ o a s Tta ll, Tiptur Tall (both from India), West African Tall, Philippines Ordinary Tall and Sri Lanka Tall) have many fruit characters in common. In other words, in most of the coconut growing countries, the cultivators considered the fruit type of these cultivars as the ideal. The three dwarfs of Malaysian origin appeared in the same cluster. However, the dwarfs did not exclusively form a cluster, except for the one consisting of Surinam Brown Dwarf and Chowghat Green Dwarf. The accessions that are distinct apart are all of Tall type. The accessions from the Pacific Ocean and South-East Asian regions were spread throughout the dendrogram, confirming bat these regions offered maximum variability. The indigenous collections also exhibited enormous variability. The correlation among the fruit characters was attributed to three causative factors, the first one related to weight measurements, second is for nut-constituents and third for the husk. The important characters that cause divergence as obtained from the canonical analysis were, weight of fruit, length of fruit, volume of cavity, weight of shell and per cent husk to fruit weight.Item Field evaluation of forecasting model for cashew yield in large plantations(2007-02) George, M.V.; Amarnath, C.H.; Bhagavan, S.; Vijayakumar, K.A method to forecast the cashew yield from large plantations based on biometrical characters and yield attributes was developed and field tested in the four cashew estates at Muliyar, Periya, Adhur and Perla in Northern Kerala covering an area of about 2100 ha belonging to the Plantation Corporation of Kerala in Kasaragod district and at National Research Centre for Cashew (Experimental Station), Shanthigodu, D. K., Karnataka covering an area of about 40 ha. Tne yield estimates arrived at were found to be reasonably precise with an average deviation of 6.7% ai Kasaragod and 17.9% at Shanthigodu with the actual yield.Item Field evaluation of forecasting model for cashew yield in large plantations(1989-03) George, M.V.; Amarnath, C.H.; Bhagavan, S.; Vijayakumar, K.A method to forecast the cashew yield from large plantations based on biometrical characters and yield attributes was developed and field tested in the four cashew estates at Muliyar, Periya, Adhur and Per la in Northern Kerala covering an area of about 2100 lia belonging to the Plantation Corporation of Kerala in Kasaragod district and at National Research Centre for Cashew (Experimental Station), Shanthigodu, D. K., Karnataka covering an area of about 40 ha. Tne yield estimates arrived at were found to be reasonably precise with an average deviation of 6.7% ai Kasaragod and 17.9% at Shanthigodu with the actual yield.Item Forecast of annual yield of coconuts, based on biometrical characters(1991-01) Jacob Mathew; Vijayakumar, K.; Nambiar, P.T.N.; Amarnath, C.H.Item Forecasting of cashew yield from plantations(2007-02) George, M.V.; Vijayakumar, K.; Amarnath, C.H.A method to forecast the cashew yield from targe plantations based on biometrical characters/yield attributes from small sample of trees was attempted. For this purpose, data collected during 1982 and 1983 from Cashew Plantations at Muliyar and Perla and during 1982, 1983 and 1984 from Periya belonging to the Plantation Corporation of Kerala were made use of. A double sampling procedure was used to get a ratio estimate by which a small sample (n) is used for detailed observations and a large sample (n)is used for recording an easily observable character. In gardens ranging between 100 to 300 cashew trees a maximum of 200 trees for recording the character condition of flowering graded 0 to 5 and a sub sample of 20 trees for recording the canopy area and estimated number of nuts at all stages of maturity are sufficient to give an yield estimate of the garden with 20 per cent deviation at 5% level of significance. Double sampling was relatively two to three times efficient than simple random sampling. This methodology can be safely adopted to forecast the total yield from large plantations by subdividing the area into blocks of 150 to 300 trees considering the natural boundaries and selecting a small sample of such blocks, according to any suitable sampling design.Item Forecasting of yield in coconut by using weather variables(2007-02) Vijayakumar, K.; Nambiar, P.T.N.; Jacob Mathew; Amarnath, C.H.; Balakrishnan, T.K.Influence of monthly averages of 11 weather variables viz. max. and min. temperature, vapour pressue (PN & AN) rel. humidity (FN & AN), wind velocity, hours of sunshine, rainfall, evaporation and number of rainy days up to 36 months prior to harvest of nuts was studied for two sets of data at Kasaragod. Based on regression analysis re), humidity (FN), hrs. of sunshine and vapour pressure (FN) of 17-20 meteorological weeks of the previous year, temperature (Min) of 21-24 weeks, humidity (FN) of 25-28 weeks two years previous and temperature (Min.) of 29-32 weeks three years previous were identified as important for prediction of coconut yield. The prediction model using these variables could explain 91% of the variation in yield.Item Harvest and post harvest technology of plantation crops(CPCRI, 1998-08) Bosco, S.J.D.; Sairam, C.V.; Muralidharan, K.; Amarnath, C.H.Item Harvest and post harvest technology of plantation crops(2007-02) Bosco, S.J.D.; Sairam, C.V.; Muralidharan, K.; Amarnath, C.H.Item Influence of weather on coconut yield(2007-02) Vijayakumar, K.; Jacob Mathew; Amarnath, C.H.; Nambiar, P.T.N.; Jose, C.T.; Balakrishnan, T.K.Studies were conducted on the relationship between four weekly averages of 11 weather variables viz., temperature (maximum and minimum), vapour pressure —VP (forenoon and afternoon), relative humidity—RH (FN and AN), wind velocity, hours of sunshine—HRS, rainfall, evaporation and rainy days and quarterly yield of coconut. Theseven lag periods viz., 6-8, 10-12, 17-18, 22-23. 30-31, 35-36 and 44-46 months prior to the harvest of nuts were identified as important. Of these, the last five periods correspond to some of the important developmental phases of the inflorescence like differentiation of ovary and development of stamens, growth of branches of inflorescence and formation of primordia of male flower, process of beginning of the primary bract of the inflorescence, differentiation of the outer or second bract and initiation of primordium of inflorescence.Item Optimum Plot Size for Field Trials with Coffea Arabica(1994) Sreenivasan, C.S.; George, M.V.; Subbalaksmi, V.; Amarnath, C.H.Item Pilot Sample Survey on the Incidence and Yield Loss Due to Eriophyid Mite on Coconut in Alappuzha District(2001-05) Muralidharan, K.; Jacob Mathew; Thamban, C.; Amarnath, C.H.; Anitha Kumari, P.; Chandrika Mohan; Vijayakumar, K.; Sairam, C.V.; Nair, C.P.R.; Arulraj, S.Item Pre-Harvest Forecasting of Cashew Yield Based on Biometrical Characters(2007-02) George, M.V.; Amarnath, C.H.; Vijayakumar, K.A study conducted for three years during 1978-81 to standardize a technique for forecasting cashew yield based on seven biometrical characters recorded at weekly intervals, revealed that yield can be forecast with reasonable precision (R2=o.64) by a single spot observation made during the peak flowering period (February-March). The number of variables could be brought down to three viz. the number of nuts on the tree, condition of flowering (graded 0 to 5), and canopy area, without substantially affecting the accuracy of the estimate (A* =0.61).Item Spatial Price Integration Of Regional Cocoa Markets In India And With World Market: A Co- Integration Approach(2011) Radhika, C.; Jayasekhar, S.; Muralidharan, K.; Amarnath, C.H.Item Trends In Coconut Area And Production In India(1984) Prafulla K. Das; Vijayakumar, K.; Balakrishnan, P.; Damodaran, V.K.; Remabai, S.; Amarnath, C.H.Between 1950-51 and 1980-81 though the area planted under coconut has been quite noticeable, the production growth rate has always lagged behind the planting rate, suggesting that productivity is declining. During the 1970s, the compound growth rate of coconut yield for Kerala was (-) 2.0 per cent/annum, while the corresponding rates for the other major producing states, namely Tamil Nadu and Karnataka were 1.0 per cent and 0.17 per cent respectively. Largely influenced by Kerala, the trend in all-India productivity for the period under reference was (-) 0.9 per cent/annum. We should plan for a growth rate of 7.0 per cent to bridge the supply gap.Item Trends in Coconut Area and Production in India(1984) Prafulla K. Das; Vijayakumar, K.; Balakrishnan, P.; Damodaran, V.K.; Remabai, S.; Amarnath, C.H.Between 1950-51 and 1980-81 though the area planted under coconut has been quite noticeable, the production growth rate has always lagged behind the planting rate, suggesting that productivity is declining. During the 1970s, the compound growth rate of coconut yield for Kerala was (-) 2.0 per cent/annum, while the corresponding rates for the other major producing states, namely Tamil Nadu and Karnataka were 1.0 per cent and 0.17 per cent respectively. Largely influenced by Kerala, the trend in all-India productivity for the period under reference was (-) 0.9 per cent/annum. We should plan for a growth rate of 7.0 per cent to bridge the supply gap.Item Uniformity Trials : Optimum Size And Shape Of Plots And Blocks In Experiments With Cashew(1991) George, M.V.; Amarnath, C.H.; Jose AbrahamUniformity trials in cashew (airlayers) were laid out is the existing cashew estates at Periya, Kasaragod district, belonging to the Plantation Corporation of Kerala. The yield data from 288 trees (24 rows of 12 trees each) were collected for two year 1982-83 and 198344 by daily harvest Fair field Smiths Law Y = ax and Its generalisation y=ac-s1 where g s stand for the heterogeneity coefficients expressing the reiationship between plot size (x) in r rows of c column and the C. V. (Y) of yield were tried Graphical method and maximum curvature technique were used for working out the optimum plot size. Further the cost of experimentation per treatment to estimate the means at 10% S E. was worked out for different price situations. A plot size or 6 rows of 2 trees each forming the plot across the fertility lines was found to be the optimum for experiments with cashew.