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Open Access
Heterosis breeding in sesame (Sesamum indicum L.).
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Gayathri, G; KAU; Dijee, Bastian
The study entitled ‘Heterosis breeding in sesame (Sesamum indicum L.)’ was undertaken at the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara. The objectives of the study were to collect and evaluate different genotypes of sesame for morphological traits and yield attributes, to identify useful parents producing heterotic crosses and developing hybrids in sesame. The study also intended to develop male sterile lines in sesame through interspecific hybridization with Sesamum malabaricum. Sesamum indicum and Sesamum malabaricum accessions were collected from Kerala and Tamil Nadu and evaluated for their morphological traits. Wide range of variation was noticed for characters like plant height, number of days to flowering and seed yield per plant which contributed maximum to genetic divergence. The genotypes studied were grouped into six clusters. High genotypic coefficient of variation (GCV) was recorded for number of capsules per plant, plant height, seed yield per plant and number of branches per plant. High heritability with high genetic advance as per cent of mean was recorded for number of days to flowering, plant height, number of branches per plant, number of capsules per plant and seed yield per plant. This indicates that the characters are governed by additive gene effects and selection for these traits will be effective. Association analysis revealed that seed yield per plant was correlated to plant height, number of capsules per plant and number of days to flowering. Path coefficient analysis indicated maximum positive direct effect by number of capsules per plant, capsule length, plant height and 1000 seed weight on seed yield per plant. In order to develop hybrids, fourteen parents were selected based on the per se performance of the genotypes. They were crossed in line X tester mating design. Forty eight hybrid combinations obtained were raised in the field along with the parents and evaluated for their heterosis and combining ability effects. Parental genotypes AVTS-06-5, AVTS-06-10, IVTS-06-12, KYM-1, Tilak and TMV-6 were identified as high combiners based on general combining ability (gca) effects. Two combinations viz. AVTS-06-5 X KYM-1 and IVTS-06-12 X TMV-3 had significant values of per se performance, specific combining ability (sca) effects and standard heterosis for seed yield per plant. They can be evaluated for their hybrid vigour over locations and seasons. The crosses AVTS-06-5 X TMV-3, AVTS-06-5 X TMV-6 and TCR 3279A X KYM-1 have been identified as potential cross combinations for isolation of promising segregants as the parents involved in these crosses had high significant gca effects for seed yield per plant but the hybrids recorded non significant sca effects. Interspecific hybridization between S.malabaricum and S.indicum was attempted to develop male sterile lines. Seed set was noticed in three interspecific hybrids which failed to germinate due to embryo abortion. Hence these embryos were rescued and raised in vitro to obtain the hybrids.
Open Access
Invitro propagation in ashoka : saraca asoca (Roxb.) de wilde.
(Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, 2011) Brindha Devi, I; KAU; Sreenivasan, E
Asoka (Saraca asoca) is an important medicinal and ornamental tropical tree currently facing the threat of extinction due to overexploitation of trees occurring in forests and other natural habitats. Unscientific and destructive extraction of bark from trees has lead to acute shortage of raw bark by ayurvedic industries. Hence, the International Union for Conservation of Nature and Natural Resources (IUCN) has listed this species under ‘globally vulnerable’ category. It is also enlisted among the 36 threatened and endangered medicinal plants of India. It is considered as the sacred tree of buddhists and Hindus. Literally the term ‘asoca’ means ‘sorrow-less’ and the tree is believed to remove the grief and unhappiness. The tree has immense medicinal properties. Its bark is considered as the primary medicinal part. Due to its acute short supply compared to its demand, various development and research activities are being prioritized to conserve, utilize and improve this species. It is mainly propagated by seeds. Due to heterozygous and cross pollinated nature of the species, it never gives a true to type progeny. Therefore the present study was undertaken to standardize the technique of in vitro propagation of Saraca asoca. Standardization of suitable explants, surface sterilization procedures and culture establishment protocol, Induction of multiple shoots and Elongation of root, hardening and planting out are the major objectives of the study. Nodal segment, Internodal segment and shoot tip were the three explants tried. Various surface sterilization procedures were tried using Chloramphenicol, ethyl alcohol, 0.1% mercuric chloride and combination of ethyl alcohol and mercuric chloride in various concentration and duration, using nodal segments as explant. Surface sterilization using 70% ethyl alcohol for 3 minutes followed by 0.1% mercuric chloride for minutes proved to be the best, which gave the maximum survival percentage of 80. The next part of the study was standardisation of suitable explants for culture establishment. Among the three explants, Nodal segments gave maximum response of 60 per cent in ½ MS medium with BAP 0.5mg/l. This was followed by shoot tips in the same medium, which gave 10 per cent response. Internodal segments did not respond in any of the media used. Standardisation of basal media for culture establishment was done using nodal segments as the explants. Three media supplemented with BA 0.5 mg.l-1 were tried viz. MS, Half strenght MS, Woody plant media. Among the three, ½ MS media was identified as the best basal medium followed by MS medium. No response was seen in WPM medium. Culture establishment as well as Shoot bud initiation was attempted in ½ MS and MS media with various growth regulator combinations. Maximum response of 60 per cent was obtained in ½ MS medium containing BAP 0.5 mg/l followed by 30 percent in the same medium containing BAP 1.5 mg/l. There were no response with 2,4-D. The response obtained was callusing in all cases. Induction of multiple shooting was tried in ½ MS medium supplemented with BAP, and Kn alone as well as combinations of BAP, IAA at various concentration. Here highest response of 30 per cent of single shoots was recorded in ½ MS media containing BAP 0.5 mg/l. Response was in the form of single shoot. The single shoots with a mean length of about 1.5mm after one week of growth was obtained. With BAP 2.0 mg/l, single shoots were produced in about 5% of cultures within 54 days. Effect of Kn in various concentration ranging from 0.5 to 2.0 mg/l was found to be low in shoot induction. The maximum length of shoot of about 1.6 cm was recorded in combination of BAP 0.5 mg/l and IAA0.5 mg/l. Various combinations of IAA and IBA at different concentrations were tried for rooting of in vitro shoots. However there was no response in any of the combinations tried.
Open Access
Organic nutrition for soil health and productivity of chilli (Capsicum annuum L.)
(Department of Soil Science and Agricultural Chemistry,College of Agriculture,Vellayani, 2011) Lekshmi, V; Ushakumari, K
An investigation was carried out at the Instructional farm, attached to the College of Agriculture, Vellayani to evaluate the effect of two enriched composts viz. BM compost and EM compost at different rates alone as well as in combination with two growth promoters viz, Panchagavya and vermiwash on physico-chemical and biological properties of soil and also their impact on crop performance using chilli variety Vellayani Athulya as test crop. The results from the field experiment revealed that the plant growth characters viz. height of the plant at 30, 60 and 90 DAT and primary branches per plant at 90 DAT showed significant variation due to the application of 75% N as BM compost along with Panchagavya. The treatments did not significantly affect the biometric observation, ‘days to 50% flowering’. Significant differences were observed among yield attributing characters viz. number of fruits per plant, fruit length (cm), fruit girth (cm), fruit weight (g), green fruit yield per (g plant-1), total fruit yield (t ha-1) and total dry matter yield (t ha-1). The treatment T8 (75% N as BM compost + Panchagavya) recorded the highest values for all these characters but it was found to be on par with T7 (75% N as EM compost + Panchagavya). This shows that BM compost can be substituted with EM compost when used along with Panchagavya. With respect to quality characters, the treatment T8 (75% N as BM compost + Panchagavya) registered the highest values for capsaicin, ascorbic acid and shelf life of fruits. However ‘oleoresin’ was not influenced by different treatments. Disease incidence percentage (Colletotrichum fruit rot) was found to be reduced by the treatments with organic sources. The treatment T8 (75% N as BM compost + Panchagavya) reduced the incidence of pests and diseases to a considerable extent. Highest BC ratio also was recorded by the same treatment T8 (75% N as BM compost + Panchagavya). Post harvest analysis of the soil indicated that organic carbon, available macro and micro nutrients pH, EC and microbial load and dehydrogenase activity were increased by the combined application of enriched manures viz. 75% N as BM compost and Panchagavya or 75% N as EM compost and Panchagavya. Bulk density was found to be reduced favourably. From the results it was clearly indicated that 75% N as BM compost and Panchagavya or 75% N as EM compost and Panchagavya was superior to all other organic sources in promoting soil health and yield and quality of chilli.
Open Access
Site specific nutrient management for chilli (Capsicum annum.L) in kalliyoor panchayath of kerala
(Department of Soil Science and Agricultural Chemistry,College of Agriculture,Vellayani, 2011) Priya, U K; KAU; Sudharmai Devi C R
Site Specific Nutrient management is a technology in precision fanning that offers chance for farmers to achieve the targeted yield taking into consideration the potential yield of the crop by application of apt amount of fertilizers. The technology is farmers' friendly, eco-friendly and also consumer friendly. In Indian scenario wherein farmers are suffering from yield losses up to 40% due to micronutrient deficiency of soils mainly zinc and boron deficiencies are the yield limiting factors of production. Kerala the soils are low in basic ions that are posing serious threat to crop production. The Judicious application of chemical fertilizers along with micronutrients is necessary for sustainable crop production. The present study "Site Specific Nutrient Management in" Chilli (Capsicum annuum.L.) in Kalliyoor Panchayath Of .Kerala" was carried out to satisfy the objectives viz. study the spatial variability of area, to find outtheindigenous nutrient supply via omission trials, fix a target yield based on the potential yield of the crop and formulate a site specific nutrient recommendation to obtain the targeted yield. In order to understand the spatial variability survey was conducted at 25 sites of Kalliyoor panchayath. The results of survey showed that the soils showed wide variation in terms of soil physical and chemical properties. Soil phosphorus status , was high in all cases other nutrient concentration ranged from low to high. The spatial variability necessitated carrying out the omission trials at four different sites that were ranked according to the nutrient status into high, medium first level, medium second level and low fertility soils. From the omission trials the recovery fraction and, indigenous nutrient supply were calculated. Utilising all these parameters in QUEFT model SSNJ\:1.--tre tments were fixed. /' / / - :l.33- The high yield target was fixed at 16 t ha that was 50% of the potential yield. The nutrient recommendation generated for HYT was 104.8: 13.6: 201 kg N, P205 and K20 ha-I. Medium yield target was fixed at 168:51: 230 kg N, P205 and K20 ha- I. Taking into account micronutrient and secondary nutrient deficiencies in the soil. In high yield target soil application of micro nutrients and secondary nutrients along with application of 1 % foliar spray of boron was recommended. Micronutrients for soil application were boron @ 5 kg ha-I in form of borax, zinc @ 20 kg ha-I in form of zinc sulphate. Secondary nutrients applied were calcium @ 30 kg ha-I in form of CaS04, magnesium @ 7.5 kg ha-I in form of MgS04. The requirement of sulphur was met from soil applied zinc sulphate, calcium sulphate and magnesium sulphate. In medium yield target only soil application of micro and secondary nutrients along with the application of QUEFT generated recommendations for the crop; POP + micronutrient recommendations were evaluated. Simultaneously an absolute control was also carried out. Soil analysis was carried out for all the physical and chemical properties of the soil initially before the crop was raised, and after each harvest. So that change in soil properties as a result of application of treatments could be evaluated, since the application of fertilizer coincided with each harvest. The results derived from the experiment proved the superiority of SSNM over other treatments with respect to the yield major nutrient and micronutrient uptake. , Where high yield target registered a cumulative yield of 17. 32 tons, medium yield target registered a cumulative yield of 11.75 tons this was _much superior to POP+SNMN that registered an yield of 9.83 tons, or the package of practice recommendation that registered an yield of only 8.3 tons . Farmers practice registered inferior yield data of only 5.2 tons. The study revealed that the site specific nutrient management is an efficient technology to increase the yield of crops and hence provide additional income to the farmers; this technique also provides a -134 - scope of increasing the yield without over application of fertilizers that would result in deterioration of the soil physical and chemical properties in long run.
Open Access
Standardization of processing methods for production of quality white pepper.
(Department of Processing Technology,College of Agriculture,Vellayani, 2011) Shameena Beegum, P P; KAU; Vasanthakumar, K
The research entitled “Standardization of processing methods for production of quality white pepper”was conducted at the Department of Processing Technology, College of Agriculture, Vellayani . The study was undertaken with the objective of producing good quality white pepper using improved processing methods. The experiment was divided into three parts viz., chemical method of white pepper production, microbial fermentation method and organoleptic evaluation of the resultant products. The experiment was laid out in CRD with three replications. Seven promising bleaching agents were selected for the chemical experiment. Berries with calcium hypochlorite, calcium hydroxide, hydrogen peroxide, sodium hypochlorite, sodium hydroxide, sodium hydroxide, benzoyl peroxide and the conventional retting (control) constituted the eight treatments. Effects of these treatments on the physical and chemical properties of white pepper berries were analysed. All the physical properties except sizes of berries were significantly influenced by the treatments. Treatment with sodium perborate recorded maximum specific gravity followed by sodium hypochlorite, hydrogen peroxide. The highest value for 1000 berry weight was reported from berries treated with sodium hypochlorite. Treatment with calcium hypochlorite and sodium hypochlorite had registered a significantly higher value for 1000 berry volume. Calcium hypochlorite treated berries were having the highest yield. Berries produced by conventional retting process (control) found to be superior in volatile oil, oleoresin, piperine and non volatile ether extract and treatment with calcium hypochlorite was on par with control in all chemical parameters. Residual level of bleaching agents was found to be in a safe range for consumption. The microbial fermentation work was consisted of, isolation of organisms through enrichment culture technique, evaluation of available cultures and standardization of retting process for white pepper production. Seven isolates of bacteria IsB1 to IsB7 and eight fungal isolates IsF1 to IsF6 were obtained. Evaluation of isolates was done by assessing the pectinolytic and cellulolytic activities. The isolates IsF1 and IsF3 were also capable for degrading pectin. Degradation of cellulose was maximum in IsF3, Ay1 and Mycophyta. Bacterial isolates did not produce any zone for both asparagine and MP-5 media. Compared to bacterial isolates fungal isolates was faster in retting. Isolate IsF3, Ay1and Mycophyta were the most promising and recorded 100 percentage retting without any damage by third day itself. Amongst all the isolates, considering the retting process and quality of the product, the isolates IsF3 and Ay1 were found to be the most superior. Berries treated with sodium perborate recorded maximum over all acceptability for Organoleptic qualities eventhough it resulted poor chemical qualities. Amongst all the eight treatments, considering quality parameters and quality of developed product, treatment with calcium hypochlorite was found to be the most superior. The above study could be concluded with the findings that, prolonged retting period can be shortened to three to four days using microbial fermentation method with promising isolates IsF3 and Ay1. While opting for a better colour, bleaching with a promising chemical bleaching agent like calcium hypochlorite (0.2%) can be recommended.
Open Access
Nutrient Management for yield and quality improvement in Kacholam
(Department of Agronomy, College of Horticulture, Vellanikkara, 2012) Kavitha, P R; KAU; Meera, Menon V
Kacholam (Kaempferia galanga L.) is an important medicinal and aromatic plant of the Zingiberaceae family. In India, kacholam is cultivated throughout the plains for the rhizomes. The economic produce of kacholam is the chopped and dried rhizomes of 6-7 months maturity. Dried rhizomes are used in bulk quantities in ayurvedic medicine and in the cosmetic industry. It is used for curing inflammatory wounds, skin disorders, piles, oedema, fever, epilepsy, splenic disorders and asthma. The constituents of the rhizome oil include para methoxy ethyl cinnamate (60.24 % of the oil), ethyl cinnamate (20.66%), cineol, borneol, 3-carene, camphene, kaempferol, kaempferide and cinnamaldehyde. There is immense scope for cultivation of kacholam in Kerala, as the climatic and soil conditions are optimally suited to its growth and development. Kacholam can be grown as an intercrop in coconut gardens and it has attained the status of a cash crop of homesteads. Though there is an approved ad hoc recommendation of organic manures as well as N, P and K for kacholam, there are reports that the K dose is inadequate. Also, considering the low availability and high cost, the present organic manure recommendation of 20 tonnes ha-1 is rather unaffordable. There are also reports about the inadequacy in the availability of secondary nutrients viz., S, Ca and Mg, which may affect yield and quality of kacholam. A field experiment was conducted during 2011-2012 in the coconut garden of Water Management Research Unit, Vellanikkara to evaluate the effect of varying doses of K and secondary nutrients on yield and quality of kacholam. There were 12 treatments with 3 replications each. Treatments consisted of package of practices (POP) recommendation of 20 tonnes farmyard manure along with 50:50:50 kg N, P and K ha-1 and combinations with S, Ca, Mg and extra dose of K applied as first and second top dressing. Rhizomes were planted at a spacing of 20 x 15 cm and planting was done on 3/ 06/ 2011. Harvesting was done seven months after planting. Observations included biometric observations taken at monthly intervals, nutrient contents at 2 ½ and 5 months after planting, and at harvest. Nutrient uptakes was also worked out. Essential oil and oleoresin in rhizomes were also analysed. The soil pH and chemical parameters were analysed before and after the experiment. There were significant differences among treatments with respect to yield, essential oil, oleoresin, nutrient contents and nutrient uptake. With respect to yield, the treatment receiving S applied either at first top dressing or at second top dressing and that with S, Ca and Mg recorded highest yields as compared to other treatments. Essential oil content also showed the same trend as that of yield. But in case of oleoresin, the content was more only in the treatments receiving S as first and second top dressing. This treatment resulted in highest uptake of all nutrients except Ca at harvest. Application of the secondary nutrients thus had a direct positive effect on yield and quality. Changing the N:K ratio of present NPK recommendation resulted in reduction of yield and other quality parameters. The yield and quality parameters with the reduced organic manure dose were found similar to the present POP. Increased phosphorus content of soil observed after experimentation indicated the possibility of reducing the recommended phosphorus dose. Supplementing S, Ca and Mg with a reduced organic manure dose is also to be tested.
Open Access
Integrated insect pest management (IIPM) and Biological Control based integrated pest management (BIPM) in rice
(Department of Agricultural Entomology, College of Horticulture,Vellanikkara, 2012) Pramod Kumar, KAU; Ranjith, A M
Rice is the staple food of India and most parts of the world. India has a history of pest outbreaks resulting in extensive losses in rice production, with a lot of factors contributing to it. For managing pests in rice many farmers use only the parasitoid Trichogramma (available as trichocards) and sometimes with the addition of Pseudomonas fluorescens. Trichogramma will manage only yellow stem borer and leaf folder (YSB and LF). Other lepidopteran pests and sucking pests have to be tackled by adopting other management practices. Even trichocards are wasted due to wrong application techniques. Light traps can be used to monitor the incidence of YSB and LF to aid in the placement of trichocards. Hence the present study “Integrated insect pest management (IIPM) and biological control based integrated pest management (BIPM) in rice” was taken up with the objectives of separating/fractionating the contribution of biological control based integrated pest management (BIPM), need based super imposition of integrated insect pest management(IIPM) over BIPM, synchronizing trichocard with moth emergence to explore the possibility of reducing trichocard numbers, evaluation of trichocard dispensing technologies and economic analysis of these operations. The experiment was conducted in transplanted rice and direct sown rice at State Seed Farm, Mannuthy. Both BIPM and IIPM strategies were implemented. Two light traps were installed in the field. The trichocards @ 5cc ha-1 were released four times in treated plots to suppress the yellow stem borer and leaf folder based on moth emergence. Other treatments included application of Beauveria bassiana and neem oil garlic extract 2% in BIPM plot and need based application of insecticides in IIPM plot for managing the pests. Results revealed that the relationship between light trap catches of yellow stem borer (Scirpophaga incertulas) and dead heart/white ear head damage did not differ significantly between transplanted and direct sown rice and trap catches were also low in both the cases. Considering the percentage damage, it was seen that control plot shows significantly high damage compared to other treatments. After sixth fortnight, the application of insecticides in IIPM and botanicals in BIPM plots reduced the damage and resulted in more yield. While observing the relationship between light trap catches of leaf folder (Cnaphalocrocis medinalis) and number of leaves damaged in transplanted and direct sown rice, less damage was observed in BIPM plot compared to other treatments. Considering the percentage damage, it was observed that control plot showed significantly high damage. After sixth fortnight , when other pests started infesting the crop, application of insecticides in IIPM and botanicals in BIPM plots reduced the damage and resulted in more yield. The yield data of various treatments indicate that the IIPM plot recorded highest yield i.e. 9,150 kg ha-1 in transplanted and 8,600 kg ha-1 in direct sown rice in comparison to BIPM (8,425 kg ha-1 and 7,975 kg ha-1) and control (6,115 kg ha-1 and 5,225 kg ha-1). The highest benefit cost ratio was recorded in IIPM (1.49 and 1.53:1) followed by BIPM (1.36 and 1.41:1). In the experiment to synchronize trichocard release with moth emergence for possible reduction of trichocard numbers, four releases starting from second to fifth fortnight could suppress both yellow stem borer and leaf folder. Different trichocard dispensing techniques have an important role in suppressing the yellow stem borer and leaf folder. In the cup method adults are restricted inside the cup and hence, leaf clipping method or coconut leaf method are recommended and also discourage the use of cup method. The results reveal that for minimizing pest incidence, providing protection and for phytotonic effects, seed treatments with insecticides and Pseudomonas is best suited. Major rice pests can be monitored by installing the light trap in the field and it is possible to synchronize the trichocard releases with moth emergence of yellow stem borer and leaf folder. Egg parasitoids T. japonicum and T. chilonis are effective against yellow stem borer and leaf folder only. BIPM method is best for managing leaf folder and IIPM for yellow stem borer. It is necessary to use need based application of insecticides, neem oil garlic extract and other biocontrol methods in controlling insect pests. Maximum yield is attained in IIPM plot followed by BIPM in transplanted and direct sown rice and benefit cost ratio was high in IIPM followed by BIPM method.
Open Access
Identification of paprika (Capsicum annuum L) genotype(s) for yield and quality characters
(Department of Olericulture, College of Agriculture,Vellayani, 2012) Lekshmi, S L; KAU; Sreelathakumary, I
The experiment entitled “Identification of paprika (Capsicum annuum L.) genotype(s) for yield and quality characters” was conducted at the Department of Olericultue, College of Agriculture, Vellayani, during the period 2011-2012. The study envisaged assessment of genetic variability in paprika and to study the influence of harvest maturity on quality parameters. Fifty three accessions of paprika were collected from different parts of country and grown in the field in RBD with three replications. The analysis of variance revealed highly significant differences among the 53 accessions of paprika for all the characters studied viz., plant height, primary branches, days to flowering, days to maturity, node to first flower, height of node to first flower, fruit length, fruit girth, fruit weight, fruits per plant, yield per plant, pedicel length, fruit: pedicel ratio, flesh thickness, seeds per fruit, flesh: seed ratio, driage, oleoresin, colour, ascorbic acid, capsaicin, bacterial wilt and leaf curl virus incidence. Among the accessions CA 6 recorded highest yield per plant (776.12 g) and CA 12 recorded maximum number of fruits (265.33). Fruit weight was highest in CA 47 (13.43 g). High phenotypic coefficient of variation and genotypic coefficient of variation were observed for yield per plant, fruits per plant, fruit weight and primary branches per plant. High heritability and high genetic advance also observed for these characters. The path analysis revealed that fruit weight, fruits per plant, plant height and primary branches had direct effect on yield per plant. Correlation and path analysis revealed that fruits per plant is the primary component as evident from the positive correlation as well as high direct and indirect effect on yield. Maximum oleoresin content was observed in CA 7 followed by CA 29 and CA 37. CA 2 recorded a high color value with pungency and CA 37 recorded a high colour with low pungency. CA 38 recorded maximum ascorbic acid content. CA 34 and CA 40 had the minimum pungency and CA 10 recorded the maximum pungency. Bacterial wilt and leaf curl virus incidence among the 53 accessions were studied. CA 33, CA 34, CA 35 and CA 47 recorded less incidence of both diseases. Based on Mahalanobis D2 analysis the current genotypes were grouped into four clusters. Cluster I was the largest with 34 accessions, followed by cluster IV with 15 accessions and cluster II with three accessions. Cluster III had only one accession. In the present study maximum divergence was observed between clusters II and IV as shown by their high intercluster distance. The minimum intercluster distance observed between the clusters I and II indicated a close relationship among the accessions. Based on selection index including both quantitative and qualitative characters CA 34 (Local, Dharwad) was ranked first followed by CA 7, CA 6, CA 33 and CA 35. The accessions were genetically catalogued and the result revealed distinct variations among the accessions for vegetative, inflorescence, fruit, seed and quality characters. Quality characters showed significant differences among the accessions and harvest maturity stages. Oleoresin, colour and capsaicin content in the paprika fruits were found to increase as the age of the fruits increased. Ascorbic acid content in the fruits increased from turning stage to red ripe and then declined. On the basis of the present study the high yielding accessions can be grouped into low pungent and pungent paprika. Among the low pungent, high yielding accessions CA 34, CA 33 and CA 35 recorded high colour value also. CA 6 and CA 7 are promising high yielding pungent paprika accessions. These accessions can be utilized for further crop improvement programmes.
Open Access
Wood quality evaluation of tree species raised in research trials of the Kerala forest department at various localities
(Department of wood Science, College of Forestry, Vellanikkara, 2012) Sindhumathi, .C.R.; KAU; Anoop, E.V
A study entitled “Wood quality evaluation of tree species raised in research trials of the Kerala Forest Department at various localities” was conducted in the College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the period 2010-2012. The objective of the study was to evaluate the wood quality of Pterocarpus dalbergioides Roxb., Swietinia macrophylla King. and Pericopsis mooniana (Thwaites) Thwaites, raised in research trials of the Kerala forest department at three localities, viz., Mananthavady research range at Wayanad, Olavakkode research range at Palakkad and Nilambur north research range at Nilambur districts, Kerala. Increment core samples and wooden blocks were collected at breast height from trees, selected at random for each species. These samples were subject to intensive investigations to explore the radial variation in anatomical properties as well as variation between species. The study revealed that most of the anatomical properties varied significantly within species and between species. Tree species were also felled to assess the strength characteristics as well as to study the various physical properties. Specific gravity was higher in P. mooniana, the other two species showing similar values. Heartwood – sapwood ratio showed significantly higher value in S. macrophylla, whereas the other two species were at par. Tangential shrinkage showed higher value compared to radial shrinkage in all the three species. Results revealed that P. mooniana exhibited better strength properties which was almost similar or even better than teak as reported by Sekhar (1988). P. dalbergioides showed lower values for strength properties when compared to natural grown P. dalbergioides (Limaye, 1933). Even though P. mooniana showed higher strength properties compared to the two species, overall results revealed that all the three species has good potential for being used as various solid wood purposes. Regression analysis revealed that P. mooniana and P. dalbergioides showed linear relationship between specific gravity and anatomical properties. The present results on wood quality can be used as a baseline data for future tree improvement aspects of these species with reference to wood quality and bring out their potential utility for future afforestation programmes and various end uses.

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