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Open Access
Integrated culture of fish with micropropagated plants in a recirculatory system
(Department of Aquaculture, College of Fisheries,Panangad, 2012) Navya, R; KAU; Devika Pillai
An experiment was designed to study an integrated recirculatory sytem with micropropagated aquarium plants, fish and indigenous filter materials like coir, vetiver and bamboo as the filter media. The plants selected for the study were Bacopa caroliniana, Anubias minima, Aponogeton ulvaceus, Rotala rotundifolia and Nymphoides cristata. The first part of the work was to standardise the micropropagation techniques for the above said plants. Murashige and Skoog medium (half and full strength) was used as the basal medium for the establishment of cultures. The explants varied from nodal segments, rhizome buds, leaf petioles and lateral buds. Surface sterilization was carried out with a range of sterilants like mercuric chloride solution, ethyl alcohol, sodium hypochlorite solution etc. for varying durations and concentrations depending on the type of explant. Effect of growth regulators on explants were studied using auxin IAA and cytokinins, BA and Kn. A liquid culture media with 1.5mg l-1 BA and 0.1mg l-1 Kn concentrations was the best medium for Bacopa caroliniana. A combination of auxin cytokinin like 1.5 mg l-1 BA and 1.0 mg l-1 IAA in liquid culture was the best medium for Rotala rotundifolia. In Nymphoides cristata, hormone concentration of 1.0 mg l-1 each of BA and IAA in liquid culture gave the best results. In Anubias minima, a full MS solid medium with 6.0 mg l-1 of BA gave better results compared to lower levels of BA. In vitro trials for Aponogeton ulvaceus was not successful due to the exudation of phenolic extracts in all the treatments which eventually lead to the death of the tissues. Hardening success was 90 percent, 100 percent, 70 percent, 100 percent in the case of Anubias minima, Nymphoides cristata, Rotala rotundifolia and Bacopa caroliniana respectively. The micropropagated plants were incorporated in the recirculatory system along with fish and three different biofilter materials like coir, vetiver and bamboo splits. The study focused mainly on the filtering efficiency of the three filters based on the nitrification curves. The plants were included in the system to be a part of biofilter and their exclusive role in nitrification was not studied since this is a preliminary work. A nitification graph was plotted with the observed values of ammonia, nitrite and nitrate in the three different biofilter systems and compared with a control. It was inferred that coir fibres were the best of filter materials tried in nitrification followed by bamboo and vetiver. The control system took more time (45 days) in stabilizing ammonia levels due to lack of a substratum for growing nitrifying bacteria.
Open Access
Evaluation of foliage plants for interior plantscaping
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 2012) Alex, R; KAU; Sudhadevi, P K
Studies were undertaken in Department of Pomology and Floriculture, College of Horticulture, Vellanikkara during 2010-2012 to evaluate the foliage plants for interior plantscaping. The study comprised of four experiments in which fifty foliage plant species were selected for evaluation under two growing structures having two different systems viz., open ventilated and fan and pad. Air Pollution Tolerance Index of all the selected species of foliage plants were computed and based on that, ten species was selected and their performance under different indoor light conditions was studied. The air borne microbes and dust filtering efficiency of these ten indoor foliage plant species were also evaluated. When the growing structures, viz., open ventilated & fan and pad greenhouses were compared, the plants kept in fan and pad system were found to be superior than the plants kept in open ventilated greenhouse with regard to most of the characters. So the fan and pad system could be considered as the best for growing the foliage plants. But precautions should be taken to check the humidity levels. Fifty selected species of foliage plants were classified into six categories namely rosette, tree-like, flowering, upright, grass-like and climbing and trailing based on their growth habit. Among the rosette type, Anthurium crystallinum, Calathea zebrina, Philodendron wendlandii and Homalomena wallisii could be recommended for their compactness. Chrysalidocarpus lutescens, Codiaeum variegatum ‘Punctatum aureum’, Ficus benjamina, Licuala grandis, Rhapis excelsa and Schefflera arboricola could be recommended among the tree-like species which could be utilized to decorate bigger indoor places. In flowering foliage plants, Anthurium andreanum ‘Bonina’, Spathiphyllum wallisii and Kalanchoe blossfeldiana could be recommended for any indoor conditions as they would improve the interior environment with their attractive flowers as well as foliages. Aglaonema pseudobracteatum, Dieffenbachia amoena, Sansevieria trifasciata ‘Laurentii’, Dracaena ‘Purple Compacta’, Peperomia obtusifolia ‘Sensation’ and Zamioculcas zamiifolia could be recommended in upright foliage plants. Among grass-like species, Cyperus alternifolius, Chlorophytum ‘Charlotte’ and Ophiopogon jaburan ‘Variegata’ were found to be good and recommended to place them in groupings. Among climbing and trailing plants, Scindapsus aureus, Syngonium podophyllum, Philodendron ‘Ceylon Gold’ and Philodendron elegans were found best and recommended for places like staircase, balcony etc. The Air Pollution Tolerance Index (APTI) of the foliage plant species under the study was computed for three different seasons, viz., March-April, June-July and October- November and based on this they were categorized into sensitive, intermediately tolerant, moderately tolerant and tolerant. It was observed that Anthurium andreanum ‘Bonina’, Calathea zebrina and Dracaena ‘Purple Compacta’ had the highest APTI value and was tolerant to air pollution irrespective of the seasons. In all the seasons, Aglaonema pseudobracteatum, Kalanchoe blossfeldiana, Sansevieria trifasciata ‘Hahnii’, Spathiphyllum wallisii, Syngonium podophyllum, Tradescantia spathacea ‘Sitara’ and Zamioculcas zamiifolia were found to be the most susceptible and they could be recommended to be used as indicator plants for pollution. Other species could also be utilized based on their tolerance levels with respect to the seasons. Based on the APTI value, ten species were selected (two from each category) and their performance was studied under five different indoor light conditions viz., low (<800 lux), medium (800-2000 lux), high (>2000 lux), supplementary (800-2000 lux) and supplementary light with air condition. From the results, it was found that most the foliage plants could thrive well under medium light condition. In addition with that, under air conditioned zone with supplementary light, species like Anthurium andreanum ‘Bonina’, Philodendron elegans and Syngonium podophyllum could be recommended. Species like Chrysalidocarpus lutescens, Rhapis excelsa and other palms could be recommended for areas with high light intensity. The performance of Scindapsus aureus was found good with regard to almost all the desirable characters in all the light conditions. The foliage plants were found very effective in reducing air borne microbes present in indoor conditions. The maximum amount of reduction (35.43 %) was recorded in the zone with medium light intensity where there were 127 Total colony forming units (Tcfu) without plants, which was reduced to 82 Tcfu when foliage plants were kept under the same zone. Regarding the dust filtering efficiency, the maximum amount of dust (3.57 gm-2) was found to be removed from the atmosphere by Syngonium podophyllum. Based on the amount of dust collected by the species, they could be arranged as Syngonium podophyllum > Philodendron elegans > Ficus benjamina > Philodendron ‘Ceylon Gold’> Anthurium andreanum > Schefflera arboricola > Chrysalidocarpus lutescens > Rhapis excelsa > Spathiphyllum wallisii > Scindapsus aureus.
Open Access
Impact of pesticides on abiotic and biotic components in rice ecosystem of Kuttanadu
(Department of Agricultural Entomology, College of Agriculture, Vellayani, 2012) Priya, Mohan; KAU; Naseema Beevi, S
Investigations were carried out in the main crop seasons of Kuttanadu during the years 2007-08 and 2008-09 to study the pesticide use pattern and extent of contamination in rice ecosystem of Kuttanadu, to assess the relative impact of conventional and IPM practices and to suggest measures for minimizing the residue hazards. The survey conducted on the pesticide use and consumption pattern in the three river catchments in Kuttanadu viz., Pampa, Manimala and Meenachil revealed that the herbicide use in Kuttanadu has increased during the past five years while a decreasing trend was noticed the case of insecticides. The consumption of pesticides in Kuttanadu ranged from 0.56 to 3.38 kg ai ha-1 with 0.3 to 1.63, 0.04 to 0.0973 and 0.09 to 0.947 kg ai -1 for herbicides, fungicides and insecticides respectively. The most popular herbicide, fungicide and insecticide were 2,4-D, hexaconazole and acephate respectively. The survey further revealed that during pesticides application, the spray men were not using any protective gadgets as per FAO guidelines while 18 per cent of the spray men were using partial protective measures. The label information on the pesticides as well as the safety guidelines for disposal of used pesticide bottles and wash water of sprayer were not followed by the majority of farmers. Health problems like head ache and dizziness, skin irritation etc were reported by the spray men. Multi Residue Methods in water, soil, paddy grains, paddy straw, duck meat and fish were developed and validated by conducting recovery studies. Five important validation parameters viz., recovery per cent age, repeatability, reproducibility, linearity, limit of detection and limit of quantification were established for eleven candidate pesticides viz., phorate, dimethoate, lindane, methyl parathion, malathion, chlorpyriphos, alpha endosulfan, hexaconazole, ediphenphos, lambda cyhalothrin and deltamethrin. These methods were found to be suitable for analyzing multiple pesticide residues in different components of Kuttanadu rice ecosystem. The estimation of residues from different components were performed using gas chromatograph (GC) and high performance liquid chromatograph (HPLC). Monitoring studies were conducted in three different river catchments in Kuttanadu. Samples of soil and water were collected from rice field, field outlet, drainage channel, stream and river at different growth stages of the crop viz., seedling stage, tillering stage, booting stage, milky stage and after the harvest. Samples of rice grains, straw, fish, mollusk, duck meat, eggs and animal meat (beef) were collected from the rice ecosystem. Data revealed that the pesticides detected included 2,4-D, chlorpyriphos, dimethoate, phorate, phorate sulphone, carbaryl, triazophos,monocrotophos, quinalphos and malathion. The pesticide residues were below detectable limit in samples of rice grains, straw, fish,mollusk, duck meat, eggs and beef collected from the rice ecosystem. Studies conducted on the impact of IPM and conventional practices on major pests, natural enemies and neutrals revealed that during the initial stages (25DAS), the pest : defender ratio was 1.031 and 1.141 in the IPM and conventional plots, while at 45 DAS the pest: defender (P:D) ratio was 1.836 and 2.118 respectively. At 65 DAS the P:D ratio was 1.763 and 3.037 respectively in IPM and conventional plots. The mean yield of paddy grains and straw were higher in IPM plots. Studies on the dissipation of pesticides being used in Kuttanadu revealed that the dissipation in field conditions was mainly influenced by the water management practices prevailing in the region. The half life of 2,4-D, chlorpyriphos, acephate, hexaconazole, moncrotophos and triazophos in soil were found to be 0.59, 2.24, 0.75, 1.36,1.23 and 2.79 days respectively. The half life of lambda cyhalothrin and methyl parathion in rice plants were 1.51 and 1.38 days respectively. The present studies revealed that appreciable quantity of pesticide residues were present in the field and field outlet while the quantity of pesticide residues present in the drainage channel was low. The pesticide residues in river and stream were below detectable limit. Estimation of dermal exposure of spray men to pesticides during application of pesticides in Kuttanadu rice ecosystem revealed that the dermal exposure of hexaconazole and triazophos per man were calculated to be 3.76 +0.116 mg man-1h-1, 6.20 +0.152 mg man-1h-1respectively. The study emphasizes the need for extensive study to be conducted at compartmental level to assess the exact route of dissipation of the pesticides applied and to arrive at the extent of environmental impact due to their application. A safe pest control strategy envisaging the use of pesticides need to be developed and recommended based on the detailed study in the ecosystem. The farmers and the workers are to be trained properly so as to follow judicious plant protection procedures to ensure Good Agricultural Practices in rice cultivation in the region without disturbing the natural eco system for sustainable development.
Open Access
Bio intensive management of blast disease of rice (Oryza sativa L.)
(Department of Plant Pathology, College of Agriculture, Vellayani, 2012) Yamini, Varma C.K; KAU; Santhakumari
The present study on ‘Bio intensive Management of Blast Disease of Rice (Oryza sativa L.)’ was conducted at College of Agriculture, Vellayani and Regional Agricultural Research Station, Pattambi during 2008-2010. A survey conducted during kharif and rabi seasons 2008, in six panchayats from three different blocks, in Palakkad district, revealed that maximum disease incidence was in Pattithara panchayat during rabi and maximum disease severity was in Chalissery panchayat during kharif. The disease intensity and severity were high during kharif season, than rabi and in all the panchayats disease incidence occurred, 60 days after sowing. The fungus produced symptoms on leaves and neck of panicle. Sixty isolates from leaf samples were obtained from the six panchayats which proved the Koch’s postulates. After preliminary screening, thirteen isolates out of the 60 were selected. Out of the thirteen isolates, five isolates, P2, P4, P5, P9 and P12 had high virulence and these were selected for further studies. Among the five isolates the most virulent isolates like P4, P2 and P12 were having dark black coloured colonies with good growth. The isolate from Chalissery (P4) which was highly virulent, with maximum radial growth, mycelial dry weight, conidial size, and sporulating nature was selected for further studies. The isolate was tentatively identified as Pyricularia oryzae and further confirmed at IARI, New Delhi with accession number, as ITCC-7019. Among the media tested Potato Dextrose Agar was best followed by Oat Meal Agar. Among the liquid media, the Potato Dextrose broth supported maximum growth of Pyricularia. The optimum range of temperature for growth of Pyricularia was 25 – 30 °C, and pH value for maximum growth was 6.5. The most potent fungal antagonist Trichoderma sp. was obtained from Kadambazhippuram panchayat and the bacterial antagonist fluorescent pseudomonad was obtained from Thrithala panchayat. The per cent of inhibition was highest for Trichoderma sp. under in vitro conditions and hence this culture was selected as the fungal antagonist for further studies. The hyphae of the Trichoderma were found to coil around the hyphae of blast pathogen and in some areas disintegration of pathogen hyphae were also observed. Based on the morphological characteristics of the fungal antagonist the isolate was tentatively identified as Trichoderma harzianum and further confirmed at IARI, New Delhi, with accession number, as ITCC-7018. The fluorescent pseudomonad with highest percentage of inhibition was selected as bacterial antagonist for further studies. Based on the morphological, cultural, biochemical and physiological characteristics, the bacterial antagonist has been tentatively identified as Pseudomonas fluorescens biovar - 1. Among the plant products, the percentage of inhibition on the growth and spore germination of Pyricularia oryzae was significantly higher for the Palmarosa oil @ 0.5ml/ l) under in vitro conditions. Neemazal @ 5ml/ l was the second best plant product. The percentage reduction of spore germination was also highest for Palmarosa oil followed by Neemazal. Carbendazim (1.5g/ l), followed by Propiconazole (1ml/ l) were the best performing fungicides under in vitro conditions and they were selected as the best two chemical fungicides for further studies. Two blasticides viz., Isoprothiolane (1.5ml/ l) and Carpropamid (1ml/ l) were also selected as additional treatments. Salicylic acid (0.1ml/ l) and Benzoic acid (0.1ml/ l) were selected as best two resistance inducers from the pot culture experiment – I, since they reduced the disease severity significantly and increased the yield. In pot culture experiment-II, plants treated with Palmarosa oil + Carbendazim (T23) had significantly reduced the blast disease. Next best performance was when Salicylic acid combined with Pseudomonas fluorescens or Trichoderma. The two biocontrol agents, Pseudomonas fluorescens and Trichoderma were effective when individually combined with plant products like, Palmarosa oil, or Neemazal, or resistance inducer, Salicylic acid. The biometric observations like, height of the plant, number of total and productive tillers, grain yield and straw yield were also considerably higher for the above treatments. The best nine treatments with lowest PDI and highest yield from this experiment were selected for field experiments. Palmarosa oil and Neemazal was compatible with Trichoderma, but the systemic fungicide, Carbendazim inhibited growth of Trichoderma followed by Propiconazole. Pseudomonas fluorescens was compatible with the two plant products, Palmarosa oil and Neemazal as well as two fungicides, Carbendazim and Propiconazole. It was also found that T. harzianum and Pseudomonas fluorescens were compatible to each other. Field Experiment-I showed that 75 DAT, T23 (Palmarosa oil + Carbendazim) had significantly lowest percentage of disease incidence and this was on par with T21 (Palmarosa oil + Salicylic acid), T36 (Trichoderma + Pseudomonas fluorescens + Salicylic acid) and T34 (Trichoderma + Pseudomonas fluorescens + Palmarosa oil). The treatment T23 (Palmarosa oil + Carbendazim) had the highest effect on reducing the PDI, 75DAT along with four treatments viz., T21, T27, T36 and T34 which were on par in their effects. The treatment T23 (Palmarosa oil + Carbendazim), produced significantly more height, higher number of total tillers, and productive tillers. Significantly higher grain yield /ha was obtained for T23 and T34. Significantly maximum straw yield /ha was also obtained for T23 In the diseased plants there was a steady decrease in chlorophyll ‘a’, ‘b’ and total chlorophyll. But in the uninoculated healthy plants, chlorophyll content remained same throughout the observation period. The activity of defense related enzymes viz., peroxidase, poly phenyl oxidase and phenyl alanine ammonia lyase activity, was significantly higher in rice plants on 5th day after inoculation for the treatment Trichoderma + Pseudomonas fluorescens + Palmarosa oil followed by Trichoderma + Pseudomonas fluorescens + Salicylic acid. Enzyme activities were least in the un inoculated plants. In the second experiment (kharif 2010) 75DAT, T23 (Palmarosa oil + Carbendazim) had significantly lower percentage of disease incidence. Two additional blasticides were also on par with T23 The biometric observations also followed the same trend. Significantly maximum grain yield and straw yield /ha was obtained for T23. The pooled analysis during two succeeding years, (kharif 2009 and 2010) revealed that, T23 had the lowest PDI with highest efficiency in reducing the blast disease. Four treatments viz., T21, T27, T36 and T34 which were on par in their effects, with T23. The B:C ratio was highest for T23 (Palmarosa oil + Carbendazim) followed by T21 (Palmarosa oil+ Salicylic acid), T27 (Neemazal + Carbendazim) (2.5), T34 (Trichoderma + Pseudomonas fluorescens + Palmarosa oil), T36 (Trichoderma + Pseudomonas fluorescens +Salicylic acid) and fungicidal check T41 (Tricyclazole). Exactly the same value of the maximum B:C ratio was obtained for Isoprothiolane. The relationship between blast disease severity and weather factors during kharif 2010, indicated positive correlation between disease severity and maximum temperature, relative humidity, rainfall, and number of rainy days but negative correlation with minimum temperature. The outcome of this research work which can be recommended in the rice organic farming techniques, are the following 1. Trichoderma + Pseudomonas fluorescens + Palmarosa oil 2. Trichoderma + Pseudomonas fluorescens +Salicylic acid 3. Palmarosa oil + Salicylic acid The result of molecular diagnosis of five selected cultures of blast pathogen, based on the D1/D2 regions in PCR analysis showed 99% similarities for 4 cultures (P2, P4, P9 and P12) and 97% similarities in one culture (P5) with the Magnaporthe oryzae, which accurately proved the identity of blast pathogen.
Open Access
Quality evaluation of medicinal rice (Oryza sativa L) ev. njavara for product development and therapeutic value
(College of Agriculture, Vellayani, 2012) Reshmi, R; KAU; Nandini, P V
A study entitled “Quality evaluation of medicinal rice (Oryza sativa L.) cv. Njavara for product development and therapeutic value” was conducted to assess the major quality parameters such as physico-chemical characteristics, nutritional composition and antioxidant activity. Two eco types of Njavara rice Njavara black (NB) and Njavara yellow (NY) were procured from RRS, Moncompu and one eco type of Hraswa was obtained from ARS, Mannuthy. Hraswa was treated as the control. The study was conducted in three phases. The first phase experiment envisaged the quality evaluation of the selected rice varieties. In the second phase of experimentation, a product (grits) was developed using both the ecotypes of Njavara; Its physical, chemical, nutritional composition, sensory and shelf life qualities was assessed and finally in the third phase of experiments the product was tested for its therapeutic value viz. glycemic index and antioxidant properties. In the first experiment, the parameters selected to study under physico-chemical characteristics were moisture, size, shape, length, width, L/B ratio, colour, thousand grain weight, gel consistency, bulk density, gelatinization temperature, chalkiness index, viscography and hardness. Regarding the colour of the rice samples all the samples were red in colour. The L/B ratio and moisture content was recorded highest for NY among the three selected rice varieties. Thousand grain weight was highest for the variety Hraswa (control) and lowest for NY. The assessment of the calorific value/energy of the three rice varieties revealed that NY had the highest value for calories when compared to the other two varieties. The protein content was found to be higher in NB and lowest in Hraswa (control) variety. The evaluation of protein quality showed that values of essential amino acids like threonine, valine, methionine and isoleucine of Hraswa (control variety) was lower than the values of raw Njavara rice samples. Whereas leucine, phenylalanine, lysine and tryptophan values of Hraswa were higher than Njavara black and yellow varieties. Amino acid score (AAS) of the rice samples revealed that NY had more amino acid score than NB. Soluble fibre content was more for NB and lower for Hraswa (control) variety. NB had the highest value for total phenol content. Trace element content of the rice samples revealed that NB had the highest value for Fe. As for Mn, Zn, Cu and Se, Hraswa (control) variety had the highest values. The results of the antioxidant properties revealed that for DPPH scavenging activity and hydroxyl radical activity NY had highest antioxidant activity, with an IC50 value of 31.62 µg/ml for DPPH and 46.00 µg/ml for hydroxyl radical scavenging activity. For superoxide radical scavenging activity, NB had the highest activity with an IC50 value of 48.78 µg/ml. In the second phase of the experiment, both the Njavara ecotypes were first parboiled and then converted to grits form and its nutritional composition, sensory and shelf life qualities were assessed. The results revealed that the energy content of the NY (G) was higher when compared to NB (G). It was found that processing influences the calorific values of rice positively. The protein content was found to be highest in NY (G) and the results showed a decrease in protein content due to processing when compared to raw values. As a result of processing the essential and non-essential content of both the Njavara varieties were found to decrease and the decrease was found more in NY (G) when compared to NBG). The EAA index of the rice samples showed that NB (G) had higher value. NY (G) had higher soluble fibre content; the results revealed that soluble fibre content has decreased as result of processing. NB (G) had the highest value for total phenol content and the results revealed that after processing the total phenol content had increased. Trace element analysis of the Njavara rice samples in the present study revealed that all the trace elements viz., Fe, Mn, Zn Cu and Se increased in content after processing with NB(G) having the highest value for all the trace elements. Antioxidant properties showed that for DPPH scavenging activity NY grits had highest antioxidant activity with an IC50 value of 35.89 µg/ml. For hydroxyl radical scavenging activity also NY grits was having highest activity. (IC50 = 53.78 µg/ml). Superoxide radical scavenging activity showed that NB grits had highest activity (IC50 value = 48.78 µg/ml). To ascertain the shelf life quality of the developed product, moisture percentage, peroxide value, insect count and microbial growth was determined. The assessment of microbial growth revealed that the highest microbial load was found in NB(G) but these levels were within the prescribed specification. Results of the selection of superior variety showed that NB (G) was found to be superior in quality, but statistically the values of NY (G) and NB(G) were not having much difference. In the third phase of experiments, Njavara grits were tested for their therapeutic value viz. glycemic index and antioxidant properties. For assessing the therapeutic value, different breakfast recipes like uppuma, porridge, kozhukatta and oratti were tried in the laboratory incorporating Njavara rice grits. The formulated recipes were then subjected to sensory evaluation. Njavara grits uppuma obtained the highest score for overall acceptability. For assessing the efficacy of Njavara on the blood sugar levels, a feeding trial for 3 months was conducted among five diabetic subjects in the age group of 40-50 years. Blood sugar levels was monitored initially (before the supplementation) and finally (after the supplementation). The results revealed that, for all subjects, blood sugar levels decreased after supplementation study. Mean glycemic index and Glycemic load of the Njavara rice was found to be 72 and 36 respectively. Antioxidant properties in the blood samples of the subjects revealed that after the supplementation with Njavara the DPPH scavenging activity, hydroxyl radical activity and superoxide anion-radical scavenging activity of all the five subjects under study had appreciably increased.
Open Access
Regulation of flowering in phalaenopsis orchids
(Department of Pomology and Floriculture, College of Horticulture, Vellanikkara, 2012) Kaveriamma, M M; KAU; Rajeevan, P K

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