Browsing by Author "Nandakumar, C"

Filter results by typing the first few letters
Now showing 1 - 8 of 8
  • No Thumbnail Available
    Item
    Chemical control of thrips stenchaetothrips biformis Bagnall using synthetic pyrethroids in rice nursery
    (Kerala Agricultural University, 1988) Reghunath, P; Premila, K S; Thomas Biju Mathew; Nandakumar, C
  • No Thumbnail Available
    Item
    Management of the rhinoceros beetle (Oryctes rhinoceros L.) on coconut using new generation insecticides and botanicals
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2013) Sudhakar, S; Nandakumar, C
  • No Thumbnail Available
    Item
    Monitoring and management of the pest complex of bitter gourd (Momordica Charantia L.)
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 1999) Nandakumar, C; Saradamma, K
    Surveys were conducted in 1995-96 among one hundred bitter gourd farmers in Thiruvananthapuram district. Information on the personal and socio- economic characteristics of the farmers was gathered. Field visits indicated that among the pests at flowering, the jassid, H.phycitis and leaf feeder, D. indica were important. At early harvest, the jassid and fruitfly B. cucurbitae were the major pests. Among the natural enemies observed, the potential ones were Cjohnsoni (parasite on Hseptima), I.scutellare, Msexmaculatus and Snubilis . (predators on A.gossypii). Mosaic was severe in 12 per cent of the plots. Sixty two per cent of the farmers used a combination of mechanical, cultural and chemical measures against pests. Most common pesticides used belonged to the organophosphate group. Farmers in general adopted injudicious methods of chemical control. Seventy per cent farmers relied on mass media and interpersonal cosmopolites for information on plant protection. The most important constraint perceived by farmers was the high cost of inputs viz., plant protection chemicals, manures and fertilizers. Monitoring of fruit fly incidence using Biosense stikatrap (lure) indicated the maximum catch at eleven weeks after sowing. Ten carbofuran smeared banana fruit traps (in yellow coloured coconut shell) were found to be more efficient than one Biosense trap in trapping the fruit fly. 2 Studies on seasonal incidence of the pests and their natural enemies from 1995 to 1996 indicated that they were more from November '95 to April '96. In studies on the assessment of potential natural enemies of pests, the biology and efficacy of Cjohnsoni against epilachna beetle was observed. Among the predators viz., Iscutellare, Msexmaculatus and S.nubilis whose biology and feeding potential was studied, Msexmaculatus was observed as the most efficient predator of aphids. In another set of experiments, the effects of botanicals and chemical pesticides on pests and their natural enemies were studied. The antifeedant effect of botanicals on third instar Hseptima grubs indicated that neem seed oil (three per cent) and nimbecidine (0.40 per cent) were effective. Estimation of the comparative effect of chemical pesticides against the fourth instar Hseptima grubs showed that carbaryl and dimethoate were more effective than quinalphos and malathion. Toxicity studies of botanicals and chemical pesticides to Msexmaculatus grubs and Cjohnsoni adults as well as parasite emergence from treated larval! pupal Hseptima hosts indicated that botanicals were safe whereas, the chemicals were toxic to the natural enemies. Based on the above experiments, the botanicals viz., neem seed oil three per cent, nimbecidine 0.40 per cent and the chemical pesticides,carbaryl 0.15 per cent and dimethoate 0.05 per cent were selected for the pest management trial in bitter gourd. The reaction of five bitter gourd varieties viz., Priya, Arka Harit, Preethi, Priyanka and local to pests was tested in a field trial. Based on pest infestation and yield, Preethi was selected for the pest management trial. 3 The pest management trial was conducted for two seasons (January to April, 1996 and 1997). The results indicated that combination of botanical with chemical pesticide was the best in pest control. Based on the results the following recommendations were suggested as part of IPM strategies in bitter gourd. 1. Use variety 'Preethi' (MC-84) for planting 2. Basal drenching of combination of nee m seed oil three per cent soap emulsion with either dimethoate (0.025 per cent) or carbaryl (0.075 per cent) prior to seeding. This is recommended in areas where pests like pumpkin beetles are endemic. 3. Need based application of above till fruit set to control pests. 4. Apply fungicide (Mancozeb) to control foliar disease (downy mildew). 5. Monitor fruit fly incidence using lure trap. Set yellow painted coconut shell trap's containing carbofuran smeared banana (palayankodan) alternated with carbofuran poisoned ocimum I jaggery (2m spacing) at flowering till final harvest. 6. After fruit set, use (need based) a combination of neem seed oil three per cent soap emulsion and dimethoate 0.025 per cent.
  • No Thumbnail Available
    Item
    Pests of tulsi (ocimum tenuiflorum L ) and their management
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2007) Malini Nilamudeen; Nandakumar, C
    The seasonal occurrence and the extent of damage caused by pests of tulsi were assessed in a survey conducted at monthly intervals for one year in five locations viz., Perumpazhuthoor, Parasuvaikkal, Poojapura, Peroorkada and Vellayani of Thiruvananthapuram district. A field trial was carried out in the Instructional Farm, College of Agriculture, Vellayani to evaluate the effect of various botanicals against the pests, the spiders and on herbage yield of tulsi. The five major hemipteran pests recorded on tulsi were Monanthia globulifera W., Aphis gossypii Glover, Cajanus cajani Maskell, Phymatostetha deschampes L. and Icerya spp. The minor pests recorded were Anchon pilosum L., Lygaeus sp., Agonoscelis sp., Leptocorisa acuta (Thunb.), Pseudococcus sp., Cyrtacanthacris sp., Syngamia abruptalis Wlk., Anisephyra ocularia Fab., Lasius sp. and Solenopsis sp. A viral disease and a fungal leaf spot caused by Colletotrichum gloeosporioides Penz. were also recorded. The infestation by A. gossypii., Icerya spp., P. deschampes, A. pilosum Lygaeus sp., Agonoscelis sp., L. acuta, Pseudococcus sp., A .ocularia, Lasius sp. and Solenopsis sp. are being reported for the first time. The diseases are also being reported for the first time from Kerala. All the five major pests were polyphagous in nature. The incidence of the pests and magnitude of damage caused by them varied among the different locations as well as during the different months. Both the density dependent factors like availability of other host plants and density independent factors like temperature, relative humidity and rainfall played a major role in the distribution of pests in various locations. Except P. deschampes, the population and infestation of all the other major pests were high during summer months compared to the rainy months. The population and damage by P. deschampes had positive correlation with rainfall. The natural enemies of the pests included eight species of spiders and a dipteran (syrphid). The spiders were observed in all locations throughout the year. The syrphid Paragus serratus Fabr. was a predator of A.gossypii. An encyrtid pupal parasitoid of P.serratus was also observed. The adults of C.cajani were parasitized by Coccophagus tschirchii (Madhihassan) and the larvae of S. abruptalis were parasitized by Bracon sp. The results of the pest management trial revealed that the botanicals were not only effective in containing the pests but also safe to the spider fauna. The treatments gave higher yield also. Among the botanicals, pongamia oil two per cent or azadirachtin 0.004 per cent or neem cake soil application @ 250 kg ha-1+ NSKE five per cent could be recommended for the control of the pests of tulsi. This would be of use in the protection of tulsi in homesteads as well as in mediculture.
  • No Thumbnail Available
    Item
    Population dynamics, intensity of damage and management of the coreid bug, paradasynus rostratus dist.
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2006) Ambily Paul; Nandakumar, C
    Experiments were conducted to study the influence of alternate hosts on the population dynamics of the coreid bug, Paradasynus rostratus Dist. and consequent damage to coconut and to evolve an eco-friendly management strategy to the pest. An abstract of the work done and the results are given below. A survey conducted in Thiruvananthapuram district to study the incidence and intensity of coreid bug infestation on coconut revealed that the infestation was the highest in the coastal region. The incidence was lower in the upland and midland regions. Among the variety of crops seen in the coconut based homesteads, guava, cashew, cocoa and neem were recorded as potential hosts of the pest. Studies on the influence of alternate hosts on the population build up of coreid bug revealed that the alternate hosts were a major determinant in the extent of infestation of coreid bug on coconut. The pest multiplied on the alternate hosts during flushing, flowering and fruit formation stages of the crops and subsequently shifted to the base crop, coconut in multiple cropping systems. The changes in size and yield parameters of nut due to the infestation of P.rostratus were assessed. Nuts with negligible damage (category II) did not show any significant difference in nut shape, nut characters, copra and oil content. Significant reduction in copra and oil was observed in moderately (category IV) and , heavily (category V) damaged nuts. The endosperm was not at all formed in severely damaged (category VI) nuts. The changes in the biochemical constituents of coconut buttons due to feeding of coreid bug were studied. The phenol content in young infested nuts recorded an increase compared to healthy nuts. A progressive reduction in starch and fibre content of young nuts was obtained with increase in degree of infestation The study on the effect of infestation of P.rostratus on germination and vigour of seedlings revealed that though all the nuts in damage category II (negligible damage) to IV (moderate damage) germinated within six months, only seedlings from nuts with negligible damage (category II) had the qualities of good seedlings. The antifeedant effect of neem based botanicals and efficacy of synthetic chemical pesticides were evaluated against coreid bug. Among the botanical and chemical pesticides, neem seed oil- garlic emulsion 2 per cent and profenophos 0.05 per cent proved most effective against the coreid bug. A field experiment was conducted to evaluate the effect of selected treatments on alternate hosts for control of coreid bug in coconut. The study revealed that the combined application of neem seed oil- garlic emulsion 2 per cent + profenophos 0.025 per cent was the most effective in reducing the extent of coreid bug infestation in the surrounding coconut palms. The present study could establish the role of alternate hosts on the population buildup of coreid bug. Plant protection operations in alternate hosts against coreid bug are more effective, economical and viable options compared to those in coconut. Based on the results of the study, a package involving regular monitoring of the alternate hosts in the homesteads, removal and destruction of the egg masses and early instars of the pest and giving a need based spray with an insecticide formulation like neem oil- garlic emulsion 2 per cent + profenophos 0.025 per cent on the alternate host would be a practical and cost effective approach for reducing the damage of P.rostratus on coconut in the homesteads.
  • No Thumbnail Available
    Item
    Saccolepis interrupta, an alternate host for the rice leaf folder, Cnaphalocrocis medinalis Guen. (Pyralidae: Lepidoptera)
    (Kerala Agricultural University, 1982) Thomas, M J; Jim Thomas; Nandakumar, C
  • No Thumbnail Available
    Item
    Seasonal occurance and ecofriendly management of pests of amaranthus
    (Department of Agricultural Entomology, College of Agriculture, Vellayani, 2005) Asha, J S; Nandakumar, C
  • No Thumbnail Available
    Item
    Seasonal occurrence and ecofriendly management of pests of black pepper (Piper Nigrum L.)
    (Department of Agricultural Entomology, College of Agriculture, Vellayani., 2003) Sageetha, A S; Nandakumar, C
    Seasonal occurrence of the pests of black pepper was studied in the Instructional Farm, College of Agriculture, Vellayani from May 2002 to April 2003. Pollu beetle adults were present in the field throughout the year. Maximum population was observed during first fortnight of November 2002. There was significant negative correlation between the pollu beetle population and maximum temperature and significant positive correlation with relative humidity. Leaf damage by pollu beetle was maximum during second fortnight of November 2002. Significant negative correlation was obtained between leaf damage by pollu beetle and maximum temperature. The intensity of leaves damaged was maximum during first fortnight of December 2002. The relationship was significantly positive with maximum temperature and negative with relative humidity. Spike and berry damage by pollu beetle was maximum during the first and second fortnight of February 2003. There was significant negative correlation between spike and berry damage and minimum temperature. The top shoot borer damage had a significant negative correlation with maximum temperature and maximum damage was observed during second fortnight of ovember 2002. The damage of leaf gall thrips on leaves had significant positive correlation with maximum temperature. Maximum damage on leaves was observed during the month of April 2003. Intensity of damage by scale insects on vines had significant negative correlation with maximum temperature and maximum damage was observed during first fortnight of April 2002. Eight botanical pesticides including their combinations were evaluated with quinalphos 0.05 per cent as a check against pests of black pepper in a field experiment in the Instructional Farm, College of Agriculture, Vellayani from May 2002 to February 2003. Three sprays of the treatments were applied one each at spike emergence, berry formation and at berry maturation stage. In general, the treatments were effective and superior to control in containing the pests. Quinalphos 0.05 per cent treatment afforded maximum protection against all the pests of black pepper studied in the trial. Among the botanicals, nee m seed oil soap emulsion two per cent plus garlic two per cent plus karanja oil one per cent offered maximum protection followed by nee m seed oil soap emulsion at two and three per cent plus garlic two per cent. Clerodendron leaf and flower extract eight per cent was the least effective botanical. The yield of dried pepper was the maximum in quinalphos 0.05 per cent treated vines followed by neem seed oil soap emulsion two per cent plus garlic two per cent plus karanja oil one per cent and neem seed oil soap emulsion three per cent plus garlic two per cent and neem seed oil soap emulsion two percent plus two per cent garlic. , The benefit: cost ratio was maximum for the treatment, neem seed oil two per cent plus garlic 'two per cent (3.20) followed by neem seed oil two per cent plus garlic two per cent plus karanj oil one per cent (3.11). Three sprays of either of the above botanical combinations, one each at spike emergence, berry formation and at berry maturation stage can be recommended as an ecofriendly pest management strategy in black pepper