Browsing by Author "Sreekandan Nair, G"

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Adoption of scientific method of cultivation of rubber by small growers in Mavelikkara taluk
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1992) Madavankutty Nair, P G; Sreekandan Nair, G
An attempt was made to assess the rubber cultivation of Mavelikkara taluk of Alappuzha district. Primary data were collected through personal visits and interviews with the help of a questionnaire. Secondary data were gathered from the records available at the Field Offices of the Rubber Board. For the study, 100 units were chosen randomly from among those who planted rubber in 1985. Alappuzha district is comparatively new with respect to rubber cultivation. The region has the topography suited for rubber cultivation, with good soil and climatic features. Convertion of other crop areas to rubber was observed. There has been a tendency for raising higher number of plants per unit area than what is recommended, and only 14 per cent of the growers adopted the recommended planting distance. In majority of cases the pitting and refilling were found to be as per the recommended package of practices. Majority of the growers used advanced clones for planting. The most popular planting material had been RRII 105, which covered 92 per cent of the area under study. A general tendency for over manuring has been noticed. Intercropping was popular and some of the intercrops like betelvine were unique to this region, the feasibility of this needs further detailed studies. Cover cropping was not a regular practice in this area. There was atendency among the growers for opening the trees for tapping before attaining the recommended standard. As regards the exploitation system, out of 64 holders who started tapping, all except one followed ½ S d/2 system. The study revealed that growth of rubber is quite satisfactory in the area but indicated that the growers require more familiarization with the package of practices of the crop. Most of the growers were found not fully aware of the scientific cultivation practices for rubber. They were also found not availing the benefits of various extension schemes formulated by the Rubber Board and in short, more extension support is warranted in this line.
Biodiversity of medicinal plants in oil palm plantations
(Department of Horticulture, College of Agriculture,vellayani, 2000) Sarada, S; Sreekandan Nair, G
Biodiversity of medicinal plants in Vellayani
(Department of Horticulture, College of Agriculture, Vellayani, 2001) Jyothilekshmi, L; Sreekandan Nair, G
A study on 'Biodiversity of medicinal plants in Vellayani' was carried out in and around Vellayani lake of Thiruvananthapuram district, Kerala. The objectives of the study were to identify the medicinal plants from among the existing natural flora, to study the growth behaviour of selected medicinal plants and to assess the pharmacologically active constituents of selected medicinal plants. A total of 80 sampling units were taken usmg stratified random sampling technique, the strata being dry land, garden land, paddy field and lake area. The medicinal plants in dry land, garden land and paddy field were identified and quantified by random sampling technique using 1.0 m2 frame. In the lake area as it was difficult to use the frame the plants were collected randomly giving sufficient representation. A total of 135 plant species were identified in the four different strata belonging to 120 genera and 57 families. None of the plants were endemic. There were 118 indigenous and 17 exotic or naturalized plants. Ten important medicinal plant species were selected for detailed study and their' growth behaviour was monitored for one year. They were Andrographis panieulata, Cyclea peltata, Desmodium velutinum, Eclipta alba, Gloriosa superba, Hemidesmus indieus, Phyllanthus amarus, Scoparia duleis, Sida rhombi/alia and Solanum indieum. Emilia sonchifolia dominated in dry land area with high relative density and relative frequency. Centella asiatica was the dominating species in garden land and paddy field with high relative density. Limnophila repens was the dominant species in lake area. Most frequently occurring species in dry land was Emilia sonchifolia and in garden land Scoparia dulcis and Vernonia cinerea. Centella asiatica and Eclipta alba occurred more frequently in paddy field, where as in lake area Hydrilla verticellata occurred more frequently. The rare species in dry land were Abrus precatorius, Blepharis medaraspatensis, Carissa congesta and Rauvolfia serpentina. In garden land Acalypha indica, Capparis brevispina, Cayratia pedata, Catharanthus roseus var. alba were found to be rare. In paddy field Borraria alata, Coldenia procumbens and Portulaca oleraceae were found to be the rare species. Diplocyclos palmatus was the rare species in lake area. Dry land and garden land were found to be the most similar strata with more number of species in common. Dry land and lake area were found to be the most dissimilar strata in vegetation pair wise analysis. Lake area was found to have higher concentration of dominance as expressed by Simpson's index. Shannon's index was maximum in dry land area. Abundant species occurs more in dry land area. In dry land almost all species had equal number of individuals since Evenness index was maximum. Growth characters like plant height, plant spread, height of the first branch, number of leaves, number of roots, root length were found to increase from pre-flowering to seed set stage. These characters were found to be high in garden land compared to other strata in most of the species. The fresh and dry weight of officinal part was more in garden land condition in most of the species. In the chemical analysis it was found that in Limnophila repens there was no similar chemical constituents as that of Bacopa monnieri (brahmi). There was no bacoside content in Limnophila repens, which is present in Bacopa monnieri. So Limnophila repens cannot be used as a substitute for brahrni. The andrographolide content in Andrographis paniculata was found to be slightly higher in dry land compared to garden land. The andrographolide content was higher in dry land area because of the water stress condition in dry land. The results of this study will be helpful in evolving suitable strategies for sustainable utilization of medicinal and aromatic plants, occumng as indigenous and naturalized in and around the Vellayani lake. Such an effort would also help to conserve many of the weed species which have very high medicinal values.
Cataloguing of medicinal plants in Vellanikkara rubber estate
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1992) Raghavan, K K; Sreekandan Nair, G
The investigation revealed the presence of many medicinal plants growing as undergrowths in the rubber plantation . These plants are widely used by all the sections of the population , whether directly as home remedies or in the medicament of the different indigenous systems of medicines, or indirectly in the pharmaceutical preparation of modern medicine . It can be presumed that the vast area occupied by the rubber plantation industry in our country is richly endowed with a wide variety of plants of medicinal value which represent a great national resources. Indian officially recognizes over 2500 plants as having medicinal value , and it has been estimated that over 6000 plants are used in traditional , folck and herbal medicine , represent a great national resource. Indian officially recognizes over 2500 plants as having medicinal value , and it has been estimated that over 6000 plants are used in traditional , folk, and herbel medicine , representing about 75 per cent of the medicinal needs of the country . Some of these plants are also abundant in rubber plantations. The presence of a large number of weeds having medicinal value under the shade of rubber of weeds having medicinal value under the shade of rubber plantation give influence to fact that they can be cultivated as intercrops in the plantation provided there is internal market demand and fetches a good remunerative profit . This will bring additional income to the lakhs of rubber growers from their limited unit areas. Plants like Hemidesmus indicus and Curculigo Orchioides which find a favourable growth under the dense canopy of rubber , are of much commercial importance . But the impact of cultivation of these plants on the growth and yield of rubber needs investigation . The experiments started at the Rubber Research Institute of India in this line will definitely bring out positive developments in the near future. Further about 80 per cent of the raw materials for drugs used in the Indian system of medicine and homeopathy are based on plant product s. The credibility of these systems of medicine depending available authentic raw materials in sufficient quantities. With some 46,000 licenced pharmacies manufacturing the traditional remedies of these medicinal systems, it is necessary to plan for large scale cultivation of medicinal plants and ensure that they are accurately identified , properly processed , free of adulterants and of acceptable quality . In areas where land is limiting these crops can be cultivated as intercrops can be cultivated as intercrop. More over this will be an indirect attempt for the conversation of the endangered plants of medicinal importance.
Effect of spacing and planting material on the growth, yield and active principle in Plumbago rosea L.
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1990) Subha, S; Sreekandan Nair, G
Investigations on "Effect of spacing and planting material on the growth, yield and active principle in Plumbago rosea L." was conducted at the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during 1987-88, using factorial RBD design for exploiting this valuable medicinal plant with the following objectives: (1). To standardise the size of shoots as planting material for commercial cultivation. (2). To standardise the best spacing for better growth, yield and active principle. (3). To explore the possibility of growing Plumbago rosea L. as a commercial crop. (4). To explore the possibility of grooming this plant as an annual plant.
Effect of toxic metabolite(s) of phytophthora capsici on various stages of morphogenesis of black pepper calli
(Kerala Agricultural University, 1997) Shylaja, M R; Sreekandan Nair, G
The effect of toxic metaholite(s) of Phytophthora capsici on various stages of morphogenesis of black pepper calli was studied. The survival rate of the call! in toxin medium was influenced by the varieties / cultivars used for the study. Once the calli survived in the toxin medium, the toxic tnetabolite(s) did not inhibit further growth of the calli. The shoot proliferation and elongation were also not influenced by the metabolite(s) in the media. However, the root growth was affected adversely.
Evaluation of Ocimum lines for herbage yield oil content and eugenol
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1988) Maya S Nair; Sreekandan Nair, G
Investigations on “Evaluation of Ocimum lines for herbage yield, oil content and eugenol” was carried out at the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara during 1985-86. Twentyfour Ocimum lines collected from different places from the state and the country along with one strain (Clocimum) released from RRL-Jammu were evaluated adapting simple lattice design with the following objectives. 1) To select better types based on leaf colour aroma and flavour, 2) To study the growth and flushing behaviour of each type and to isolate superior ones having better flushing characters; 3) To select a purple coloured O. sanctum line for the Kerala homesteads; 4) To select eugenol rich strains to undertake large scale cultivation of Ocimum for essential oil production; 5) To explore the possibility of growing Clocimum under Vellanikkara conditions. The crop was raised adopting the standard package of practices recommendations. The main growth parameters studied were plant height, spread, height at first branching, total number of branches per plant, number of days to blooming, intervals of flushing and leaf area. The yield parameters studied were herbage yield per plant, herbage yield per hectare, oil content, oil yield per hectare. An attempt was also made to relate leaf colour and aroma with the eugenol content of different Ocimum lines. The results indicated that the plant height increased with the age of plants. The plant spread and total number of branches per plant were maximum during July-August and afterwards a definite pattern was not observed. Clocimum and O. gratissimum lines branched at lower heights compared to O. sanctum lines. In general, all the lines tested took more time to initial flowering after transplanting, than after first or second harvests. Clocimum and O. gratissimum lines exhibited a tendency for quick flushing but took more days for flowering after each harvest compared to O. sanctum lines. O. gratissimum lines including Clocimum have higher leaf area. The studies on yield parameters revealed that Clocimum was most superior with regard to herbage yield, oil content and eugenol followed by O. gratissimum lines. Clocimum produced a herbage yield of 59.36 tonnes/ha/year. While the highest yielder of O. sanctum produced only 22.93 tonnes/ha/year. The different lines in general, produced maximum herbage and oil yield during second harvest, followed by the third and first harvests, whereas the oil content was maximum during the third harvest followed by the second and first harvests. The percentage of eugenol was maximum in Clocimum (71.82 per cent) followed by a purple coloured O. sanctum line (59.05 per cent) collected from Nellankara, near Trichur. Clocimum produced maximum eugenol per hectare followed by O. gratissimum lines. The scoring on leaf colour and aroma with respect to eugenol content revealed that, green leaved lines had better aroma than purple leaved with one purple coloured line as exception. Here also Clocimum proved its superiority. Economics of cultivation and distillation of different ocimum lines revealed that cultivation of Clocimum is more profitable than all other Ocimum lines evaluated. When we consider the various characters of 25 different Ocimum lines, it is very well clear that Clocimum can be groomed as a commercial crop under Kerala conditions. If there is a preference for purple coloured type of O. sanctum (Krishna Thulsi) the line from Nellankara can be recommended especially for the homesteads. Hence, further investigation to probe the possibilities of growing these promising lines as pure and mixed crops in Kerala and techniques for identifying valuable chemical constituents other than eugenol is suggested.
Evaluation of the incidence of pink disease in rubber plantations in Kanjirapally taluk, Kerala state
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1991) Jain, P M; Sreekandan Nair, G
A survey was conducted to study the intensity of the incidence of pink disease in Rubber Plantations of Kanjirapally Taluk, Kerala State. The clonal susceptibility, percentage of damage, control measures adopted by growers and recovery were also evaluated. Maximum incidence is noticed in RRII 105 and minimum in PB 235. The disease incidence is maximum in the 7th year . Bordeaux paste is the common fungicide used against this disease. But only few growers know the correct method of preparation and application of Bordeaux paste. Careless disposal of infected plant parts provide large inoculum for the spread of the disease. The growers fail to detect the disease sufficiently early to carry out effective control measures. Therefore need for an intensive extension education to create awareness in small growers about the disease and its timely control is evident from this study.
In situ green manure production as mulch material for ginger
(Kerala Agricultural University, 1997) Alice Kurian; Sreekandan Nair, G; Valsala, P A
In vitro production of toxic metabolite(s) by phytophthora capsic1 and partial purification of the metabolite(s)
(Kerala Agricultural University, 1997) Shylaja, M R; Sreekandan Nair, G; Augustine, A; James Mathew
Phytophthora capsici, the causal organism of Phytophthora foot rot disease in black pepper produces toxic metaholite(s) under in vitro conditions. Maximum accumulation of toxic metabolite(s) was observed in shake cultures of 15 days incubation in Ribeiro's medium. The symptoms induced by toxic metabolite(s) were quite typical to symptoms of natural and artificial infection by the pathogen. The toxic metabolite(s) accumulated in the in vitro culture was found to be heat stable aim non-specific. The toxic metabolite(s) could not be separated using organic solvent fractionation since it is present in the aqueous fraction of the culture filtrate. However, ion exchangers like Dowex 1 and Dowex 50 could be used for separating the metabolite(s) from the aqueous fraction.
In vivo and in vitro screening of sida spp. for ephedrine content
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1998) Asha Sankar, M; Sreekandan Nair, G
Investigations on cytogenetics , flowering and seedset in ginger
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1988) Sathiabhama, K U; Sreekandan Nair, G
Investigation on cytogenetics, flowering and seedset in ginger was carried out at the Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara with the following objectives. 1. To workout the karyomorphology of ginger varieties and to study the cytogenetical polymorphism in relation to the plant morphology. 2. To study the meiotic irregularities in relation to pollen sterility in different varieties. 3. To study the effect of media and irradiation on the pollen germination and pollen tube growth in different varieties. 4. To work out the pollen – pistil interaction by fluorescence microscopy to decide on the presence of incompatibility mechanism in ginger. 5. To study the factor responsible for absence of fruitset and seedset in ginger. The study was carried on nine ginger varieties representing different geographical regions in India. Both morphological and cytogenetical characters were recorded. Studies were also conducted on pollen morphology, pollen-pistil interaction and on methods to over come the barriers in seed set. Absence of morphological difference between varieties adds to the use of cytogenetical investigations for the characterisation of varieties of ginger. The miotic index was found to be maximum during 5-6 AM. All the nine ginger varieties studied showed a chromosome number of 2n = 22. The karyotype of nine varieties of ginger studied showed considerable difference in their morphological features such as length of chromosomes, centromere position, total chromatin length and total chromosome volume. Such differences could have occurred through translocation, inversion and deletion of chromosome segments. Classification of karyotypes in ginger varieties fell in to primitive 1a and 1b group. During meiotic studies it was seen that the genome of ginger is highly unstable. Abnormalities like bridges and laggards were also present which will lead to the formation of micronuclei. Ginger flowers carry enough pollen grains in the single bilobed anther. But 60-84 per cent of the pollen grains were sterile. The high amount of meiotic irregularities may be leading to high percentage of pollen sterility. Out of the seven different media tried for pollen germination, the medium containing 8% sucrose + 60 ppm boric acid + 1% gelatin produced the highest percentage of germination of pollen grains (11.81%). The sterility and pollen germination was also correlated. Irradiation of pollan grains has been suggested to be effective in breaking the barriers in seedset. But it was seen that the irradiation of pollen grains was deteremental for the germination of pollen grains in ginger. Proper interaction between pollen and pistil is quite significant for the seed production. The study by using uv microscopy revealed the presence of spiny stigmatic surface which will prevent proper adherence, contact and germination of pollen grains. It is hard to see whether self and cross incompatibility is operating in ginger. In the present investigation many techniques for breaking incompatibility (if existing) such as bud pollination, artificial sibbing, artificial cross pollination between varieties, chemically aided pollination, mixed pollination, mentor pollination, stigma removal and artificial pollination failed to produce fruitset and seedset. Hence, based on the result the existence of incompatibility mechanism operating in ginger is quite complicated. Structural chromosomal aberrations such as translocation, deletions, inversions etc. leads to the sterility of microspores and megaspores. Pollen sterility ranging from 60 – 84 per cent might be one of the serious limitation for the setting of fruit and seeds in ginger. The spines present on the stigmatic surface prevent the pollen grain to get attached to the stigmatic surface during the act of pollination. Sterility is correlated with pollen germination and it is only upto 14.61 per cent in variety having maximum fertility. The germination of pollen grains was taking place very slowly so that flowers are withered before the pollen tube could reach the ovules. Coiling of pollen tube was also noticed during the advanced stages of pollen germination. The style length was very long (39,000 µ m) in ginger. But the pollen tube attained only 108 µ m in the best case under in vitro condition after 24 hours. So the possibility of pollan tube reaching the ovule is remote by the time flower will be withered and dehisced. The flowers were found to remain on the plant for less than 12 hours after anthesis. In essence, the absence of fruit set and seed set in ginger dose not seem to be controlled by a single factor, but an array of factors make this challenging problem more complex.
Isoenzyme variation and species relationship in genus piper
(Kerala Agricultural University, 1996) Abraham Sebastian; Sujatha, V S; Nybe, E V; Sreekandan Nair, G; Augustine, A
Eleven species of Piper including Piper rugrum were studied for variations in isoenzymes of three enzymes viz., peroxidase, esterase and glutaraate oxaloacetate transaminase. On grouping based on isoenzyme similarity, P. nigrum Linn.. P. pseudonigrum Velayudhan and Amalraj, P. bababudani Rahirnan and P. galeatum DC formed one group while P. argyrophyllum Miq. and P. attenuatum Buch-Hara constituted the second group and P. chaha Hunter, P. hapnium Miq. and P. colubrinum Link emerged as the third group. P. betle Linn, and P. longum Linn, showed their distinctness from the rest of the species. Least similarity was observed between P. colubrinum on one side and P. pseudonigrum and P. bahabudam on the other side.
Isoenzyme variation in Piper nigrum L.
(Kerala Agricultural University, 2000) Abraham Sebastian; Sujatha, V S; Nybe, E V; Sreekandan Nair, G; Mallika, V K
Isoenzyme patterns of 26 varieties of P. nigrum were compared for three enzymes viz., csterase, peroxidase and glutamate oxaloacetate transaminase. Similarity among the varieties ranged from 0.40 1.00. Wide variation was observed among the cultivated types of P. iiignini for the three enzymes analysed.
Leaf litter addition and nutrient recycling in rubber in Vellanikkara estate
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1992) Guruprasad, M K; Sreekandan Nair, G
Preliminary studies on the total quantity of the leaf litter, chemical composition of leaf litter and the nutrients released through leaf litter for recycling, in an eight year old rubber plantation of Vellanikkara Estate of Kerala Agricultural University have been attempted. During the year under study, wintering started by 14th December, 1991 and continued till 2nd March, 1992, the peak being the third week of January, 1992. During annual defoliation period total leaf litter production (dry weight) was estimated to be 4112 kg/ha, the contribution of which works out to annual addition of 63.3 kg N, 2.64 kg P, 44.0 kg K, 42.32 kg Ca and 8.93 kg Mg. During wintering, there is a gradual decline in the levels of nitrogen, phosphorus and potassium in leaves due to the shift of these nutrients to trunk. This shift was not abserved in the case of calcium and magnesium. Approximate leaf area index was also worked out and is found to be 4.26.
Productivity in relation to branching pattern and pruning in cashew(Anacardium oxidantale)
(Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1997) Nalini, P V; Sreekandan Nair, G
A study was carried out at Cashew Research Station, Anakkayam in the Kerala Agricultural University to investigate the canopy architecture of cashew and to ascertain the optimum degree and frequency of manipulation of canopy for increasing yield. The experiments were carried out during the period from March, 1992 to September, 1995. The study revealed that the resultant canopy of a seedling was massive and like a hemisphere placed above a solid cylinder. The canopy of the grafts of the two varieties used for the study appeared like a cone placed abover a short cylinder. The layers had a small size canopy which was like a hemisphere. Because of the high PWBBRn and spear shaped canopy and high yield efficiency, grafts are found to be much superior to seedlings and layers. For high density intensive management, it is shown that, the use of grafts of high yielding varieties could result in a fold increase in yield. From the experimental evidences and identification of yield components by path analysis, an ideal plant type of cashew is proposed. Experiments on canopy manipulation of cashew revealed that the crop responded very well for pruning. A pruning schedule of removal of 25 per cent of the n5 order of branches at an interval of 3 years was found to increase the yield of the crop considerably. Chlorophyll content is found to have a linear positive correlation with yield and the estimation of the chlorophyll content could be used as one of the tools for screening for high yield in cashew.
Quantification of medicinal plants identified in rubber plantation of Vellanikkara
(Department of Plantation Crops ans Spices, College of Horticulture, Vellanikkara, 1993) Ramabhadran, A V; Sreekandan Nair, G
Quantification of medicinally valuable weeds in oil palm plantations of Kerala
(Kerala Agricultural University, Vellanikara, 2002) Sarada, S; Sreekandan Nair, G; Reghunath, B R
The medicinally valuable weeds naturally growing in young, medium and mature plantations of oil palm were identified and quantified by stratified random sampling technique. Quantification of plants was done in comparison with that in the open condition. Chrysopogon aciculatus Trin. dominates in all the four strata. Naregamia alata Wight & Arn. is another dominant species in mature plantation. Hemidesmus indicus R. Br. occurs frequently in all the four strata. Another frequently occurring species in young oil palm plantation is Elephantopus scaber Linn, and in medium plantations is Chromolaena odorata King & Robinson. Phyllanthus amarus Schum.& Thonn. is very frequent in medium plantation and open condition. Holostemma adakodien Schult occurs frequently in mature plantation. Young oil palm plantation and open condition were found to be the most similar strata whereas mature plantation and open condition were the most dissimilar strata in vegetation pair-wise analysis. Medium oil palm plantation was found to have high concentration of dominance. Species diversity was the highest in mature oil palm plantation. Species evenness was maximum in open condition.
Screening of black pepper (Piper nigrum L.) calliclones for phytophthora foot rot resistance / tolerance
(Kerala Agricultural University, 1996) Shylaja, M R; Sreekandan Nair, G; James Mathew
Calliclones of different black pepper cultivars viz., Kalluvally, Cheriakanyakkadan, Balankotta, Karimunda and Panniyur-1 were regenerated from calli, screened against toxic metabolite(s) of Phytophthora capsici. The regenerants derived from screened and unscreened calli were further tested for resistance / tolerance to P. capsici using different methods of screening viz., natural screening (keeping in infected field), screening by electrolyte leakage method and screening by artificial inoculation with culture disc of P. capsici. None of the regenerated calliclones was found to be completely resistant to the disease in natural screening. However, some of the regenerants derived from unscreened calli exhibited higher degree of tolerance to the disease revealing the possibility of exploiting somaclonal variation for Phytophthora foot rot disease screening in black pepper. The calliclones of Cheriakanyakkadan recorded greater degree of tolerance to the disease as compared to others.
Seed set in ginger (Zingiber officinale rosc.) through in vitro pollination
(Kerala Agricultural University, 1996) Valsala, P A; Sreekandan Nair, G; Nazeem, P A
Different in vitro pollination techniques viz., stigmatic, srylar, intra-ovarian, placenta!, modified placental pollination and test-tube fertilization were tried in ginger flowers. The pollen grains suspended in ME, medium were used for pollination. The pollinated pistil or its part was cultured in the medium of 1/2 MS + NAA 0.5 mg 1' + BAP 2.5 mg 1 ' + coconut water 15 per cent v/v. Seed development was obtained in placental, modified placental pollination and test tube fertilization. The seed germinated under in vitro condition on supply of appropriate combination of 2,4-D, BAP and NAA