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Browsing by Author "Jacob Mathew"

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An analysis of World Coconut Situation
(Indian Coconut Journal, 1998) Jacob Mathew
Correlation studies on the nut and copra characters of West Coast Tall coconuts harvested during different months of the year
(2007-02-08) Satyabalan, K.; Jacob Mathew
Correlation studies were conducted on nut and copra characters of nuts, harvested during different months of the year from West Coast Tall (WCT) palms grown under rainfed conditions at CPCRI Kasaragod. There was significant correlations between 1) weight of fruit (unhusked nut) and weight of husked nut 2) the weight of fruit and weight of husk 3) weight of husked nut and wet weight of kernel 4) weight of husked nut and wet weight of shell 5) weight of husked nut and weight of copra 6) wet weight of kernel and weight of copra and 7) weight of shell and weight of copra in the nuts harvested during the different months of the year irrespective of seasonal effects on these characters. Slight differences in the magnitude of the association noticed in the different months can be attributed to the effect of season prevailing during development.
Crop year versus calendar year as basis for compiling annual yield in coconut
(2007-02-08) Jacob Mathew; Gopalasundaram, P.; George, M.V.; Vijayakumar, K.; Jose, C.T.
Coconuts are harvested throughout the year at an interval of about 30-60 days and the annual yield is the number of nuts obtained in a 12 month period. Two different methods of compilation of annual yield data showed that the year to year variation is more pronounced in the case of calendar year tabulation, as compared to agricultural years. When two year averages were taken, these differences were found to come down. With the help of experimental data, it has been shown that conclusions drawn can be different depending on the method of compilation of annual yield data. Analysis of mean yield for two consecutive years is suggested to overcame this problem.
Discriminant function analysis in coconut seedlings
(2007-02-08) Vijayakumar, K.; Jacob Mathew; Sukumaran, C.K.
Data on 192 seedlings from 16 families of West Coast Tall variety was utilised for constructing a discriminant function for classifying seedlings into high/low yielders at the nursery stage using 11 seedling characters. Time taken for flowering was adopted to judge a palm as high/low yielding. The function based on this criterion was significant. Girth, number of leaves, weight of the seedling and number of thick roots were found to contribute maximum in discriminating between potentially high/low yielders.
Economics of inter and mixed cropping in the coconut gardens of Kerala: Some preliminary findings
(2007-02-08) Krishnaji, N.; Chandan Mukherjee; Nelliat, E.V.; Nair, P.K.R.; Jacob Mathew; Thomas Varghese, P.
Economics of inter and mixed cropping in the coconut gardens of Kerala: some preliminary findings
(Centre for Developement Studies, Trivandrum, 1976-10) Chandan Mukherjee; Nelliat, E.V.; Nair, P.K.R.; Jacob Mathew; Thomas Varghese, P.; Krishnaji, N.
Economics of Plantation Crops
(Central Plantation Crops Research Institute, Kasaragod, 2000) Das, P.K.; Jacob Mathew; Muralidharan, K.
Effect of borax application on young coconut palms
(2005) Kamalakshi Amma, P.G.; Shanavas, M.; Prema, D.; Jacob Mathew
Eriophyid Mite
(2010) Rohini Iyer; Jacob Mathew; Chandrika Mohan; Anitha Kumari, P.; Nair, C.P.R.
Forecast of annual yield of coconuts, based on biometrical characters
(1991-01) Jacob Mathew; Vijayakumar, K.; Nambiar, P.T.N.; Amarnath, C.H.
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.
Genetic diversity of Areca catechu L. and A. triandra Roxb.
(1982-12) Bavappa, K.V.A.; Jacob Mathew
The genetic distances between 13 cultivars of A. catechu and four ecotypes of A. triandra estimated from 24 characters recorded in the productive phase for two years and the pooled data for both these years were more or less consistent. The cultivars could be grouped into six clusters in both the years and into five for the pooled data. A comparison of the groupings obtained during the two different years showed that the widely divergent clusters remained distinct in both the years whereas in the case of less divergent groups there were slight deviations in the clustering pattern. It is concluded that detection of genetic divergence is possible in the early years of productive phase. This is of considerable advantage in formulating breeding programmes. The rankings obtained by the different characters for their contribution towards genetic divergence revealed that the importance of nut and kernel characters in differentiation within A. catechu group and between A. catechu and A. triandra types. The results obtained from canonical analysis were also in broad agreement with the clustering pattern found from D2 analysis. Clustering pattern of cultivars and ecotypes obtained in the present study revealed that geographic diversity need not always be related to genetic diversity in arecanut.
Genetic diversity of Areca catechu L. and A. triandra Roxb.
(2007-02) Bavappa, K.V.A.; Jacob Mathew
The genetic distances between 13 cultivars of A. catechu and four ecotypes of A. triandra estimated from 24 characters recorded in the productive phase for two years and the pooled data for both these years were more or less consistent. The cultivars could be grouped into six clusters in both the years and into five for the pooled data. A comparison of the groupings obtained during the two different years showed that the widely divergent clusters remained distinct in both the years whereas in the case of less divergent groups there were slight deviations in the clustering pattern. It is concluded that detection of genetic divergence is possible in the early years of productive phase. This is of considerable advantage in formulating breeding programmes. The rankings obtained by the different characters for their contribution towards genetic divergence revealed that the importance of nut and kernel characters in differentiation within A. catechu group and between A. catechu and A. triandra types. The results obtained from canonical analysis were also in broad agreement with the clustering pattern found from D2 analysis. Clustering pattern of cultivars and ecotypes obtained in the present study revealed that geographic diversity need not always be related to genetic diversity in arecanut.
Identification of Prepotent Palms in West Coast Tall Coconuts Based on the Early Stages of Growth of the Progeny in the Nursery
(2007-02) Satyabalan, K.; Jacob Mathew
Monthly observations on growth rate and seedling vigour as measured by collar girth and leaf production from the time of germination taken in 599 open pollinated progeny seedlings of 16 selected high yielding families (cultivar : West Const Tall) indicated highly significant differences in growth rate of progenies between families. Correlations of these growth characters from the first to the ninth month from the time of germination with those of the tenth month showed that correlation was high and positive from the fifth month. This shows that it may be possible to identify palms of superior genetic value (prepotents) even from the fifth month based on these two growth characters of the progeny. The breeding values of six families worked out for leaf production and collar girth of the progeny during the fifth and tenth months of growth in the nursery and their yield performance in the field showed that prepotent palms, whose progenies would be high yielders, have high breeding values for both these characters. Thus it may be possible to screen a large number of palms for prepotency and identify them based on these growth characters of the progenies in the nursery during the fifth month of growth. In areas where young seedlings of less than six months old are preferred for planting, it is better to select them from five months old seedlings based on these two characters, as (hey are genetically correlated with yield of adult palms.
Identification of prepotent west coast tall palms based on progeny performance
(1975-09) Satyabalan, K.; Nampoothiri, K.U.K.; Jacob Mathew
Identification of Prepotent West Coast Tall Palms Based on Progeny Performance
(2007-02) Satyabalan, K.; Jacob Mathew; Nampoothiri, K.U.K.
A study of seedling characters and yield attributes of 43 open pollinated progenies of eight high yielding palms of West Coast Tall planted in 1953 has shown that the progenies of three palms are high yielding and that they are superior in spathe produotion and female flower production to others indicating that they are prepotents. The possibility of identifying such prepotent palms in the nursery is indicated. The progenies of such palms will help to increase the production of future plantations. Efforts to spot out more number of such palms are under way for further breeding work.
Impact of dry spells on the ontogeny of coconut fruits and its relation to yield
(2007-02) Rajagopal, V.; Shivashankar, S.; Jacob Mathew
Impact of root (wilt) disease on the yield of young coconut palms
(2007-02) Jacob Mathew; Gopinathan Pillai, N.; Kamalakshi Amma, P.G.; Robert Cecil, S.
When young West Coast Tall palms under regular fertiliser management contracted the disease during the pre-bearing period, the onset of bearing was found to be delayed. While about 90 per cent of the healthy palms flowered by the end of the eighth year, it was only around 70 per cent in palms which contracted disease during the pre-bearing stage. About 18 per cent of these diseased palms did not flower even up to the thirteenth year. Decline in yield was faster in palms which became diseased in later years. In general, about 45 per cent decline in yield was observed in diseased palms, during the course of 10 years, compared to the yield of healthy palms, while in palms which were diseased during the initial years, this loss was to the extent of 68 per cent. In Dwarf x Tall palms though the occurrence of disease was at a slower rate the increase in the disease index was higher compared to that in WCT palms. The diseased Dwarf x Tall palms, in general were giving about 60 per cent lower yields, compared to the healthy palms.
An Index for Evaluation of Coconut Germplasm in the Nursery
(2007-02) Bhaskara Rao, E.V.V.; Jacob Mathew
Coconut (Cocus nucifera L.) is a monotypic species with pantro-pical natural distribution. There are two distinguishable morphological forms, tails and dwarfs. Evaluation of coconut germplasra is a long drawn process due to its long juvenile phase, and also the time it takes for stabilisation of yield. However, preliminary evaluation can be done at different stages ; nursery evaluation based on seedling characters, at the 12th month, juvenile evaluation based on prebearing growth, characters, and economic evaluation at the stabilised yield period, based on flowering and yield data. The possibility of using this index for planning breeding programmes for varietal improvement is discussed.
An Index For Evaluation Of Coconut Germplasm In The Nursery
(1982) Bhaskara Rao, E.V.V.; Jacob Mathew
Coconut (Cocus nucifera L.) is a monotypic species with pantro-pical natural distribution. There are two distinguishable morphological forms, tails and dwarfs. Evaluation of coconut germplasra is a long drawn process due to its long juvenile phase, and also the time it takes for stabilisation of yield. However, preliminary evaluation can be done at different stages ; nursery evaluation based on seedling characters, at the 12th month, juvenile evaluation based on prebearing growth, characters, and economic evaluation at the stabilised yield period, based on flowering and yield data. The possibility of using this index for planning breeding programmes for varietal improvement is discussed.

Browsing by Author "Jacob Mathew"

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