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Open Access
Biotic agents for the management of American serpentine leaf miner, Liriomyza trifolii(Burgess) (Diptera:Agromyzidae)
(Department of agricultural entomology, College of horticulture, Vellanikkara, 2014) Jyothi Sara, Jacob; KAU; Maicykutty P, Mathew
A study on “Biotic agents for the management of American serpentine leaf miner, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae)” was carried out at the Department of Agricultural Entomology, College of Horticulture, K.A.U., Vellanikkara during 2011-2013 with the objectives of collection and identification of indigenous natural enemies and to assess the pathogenicity of the entomopathogens to explore the feasibility of utilizing them for its management. Surveys were conducted in the vegetable fields for the collection and identification of natural enemies associated with L. trifolii in three districts, namely, Thrissur, Ernakulam and Kottayam from January to March, 2011. The surveys revealed the occurrence of nine species of hymenopteran parasitoids. The per cent parasitism varied from 10.96 to 58.99 per cent among the crops surveyed. Three species of eulophids, namely, Cirrospilus acadius Narendran, C. brevicorpus Shafee & Rizvi and Aprostocetus sp. as well as the braconid, Toxares sp. are new reports for India. Among the parasitoids, Closterocerus spp. were the dominant group followed by Chrysonotomyia sp. All parasitoids were solitary, larval endoparasitoids except Toxares sp. which was larval-pupal in nature. One species each of small ants (Formicidae) and a dipteran fly (Dolichopodidae) were observed as predators on L. trifolii. In the study, no entomopathogens were observed from L. trifolii. Considering the level of pesticide consumption in vegetable crops that undermine the potential of insect parasitoids and also that no entomopathogens could be observed during the survey, it was decided to evaluate entomopathogenic nematodes (EPNs) as biocontrol agents against L. trifolii. Isolation of EPNs from 72 soil samples from Thrissur, Ernakulam and Kottayam districts yielded four isolates of Steinernema carpocapsae. Bioefficacy studies carried out on these four isolates along with Steinernema bicornutum and Heterorhabditis indica showed that S. carpocapsae Isolate - 1 had the lowest LC 50 , LC 90 and LT values indicating their higher effectiveness against the maggots of the pest. 50 Pot culture study conducted to compare the potential of S. carpocapsae Isolate - 1 with other treatments showed that azadirachtin 1 EC at 0.005% was the most effective causing 84.51 per cent mortality to the maggots of L. trifolii. This was followed by the foliar application of H. indica at 32 infective juveniles (IJs)/ maggot which caused 18.98 per cent mortality. Application of Beauveria bassiana at 1×10 7 spores/ ml was not effective. In the field evaluation, fipronil 5 SC at 0.002% was found to be the most effective treatment for controlling L. trifolii followed by azadirachtin 1 EC at 0.005%. Compatibility of the IJs of the S. carpocapsae Isolate - 1, S. bicornutum and H. indica was studied with ten commonly used insecticides in the laboratory by direct exposure method. Chlorantraniliprole 18.5 SC at 0.005% was found to be the most compatible insecticide with S. carpocapsae isolate - 1 causing only 0.17 per cent mortality to IJs at 72 hours after treatment (HAT). Quinalphos 25 EC at 0.05% and chlorpyriphos20 EC at 0.05% were highly incompatible, causing 96.17 and 92.87 per cent mortality of the nematodes. Dimethoate 30 EC at 0.04% was the most compatible insecticide with S. bicornutum and caused only 0.60 per cent mortality at 72 HAT and was followed by azadirachtin 1 EC at 0.005% with 0.78 per cent mortality to the IJs. Quinalphos 25 EC at 0.05% caused 99.93 per cent mortality at 72 HAT. Heterorhabditis indica was compatible with all insecticides except quinalphos 25 EC at 0.05% which was moderately toxic resulting in 39.6 per cent mortality. The virulence, pathogenicity and multiplication of the survived IJs were not affected by the insecticide treatments. Parasitoids and EPNs were observed as potential candidates for the management of L. trifolii. Hence future studies on the bio-ecology and mass production of dominant parasitoids and standardization of methods to improve the efficacy of EPNs are suggested for the successful control of L. trifolii in polyhouses as well as in the field.
Open Access
Genetic variability and plus tree selection in natural populations of Malaveppu (Melia dubia Cav.)
(Department of Forest biology and tree improvement, Vellanikkara, 2019) Binu Kamalolbhavan, N; KAU; Santhoshkumar, A V
Melia dubia commonly known as Malabar neem is a fast growing indigenous species. It is considered as a major wood in plywood and paper industries and the plant is put into various medicinal uses, preferred for use in packing cases, cigar planks etc. There are no identified genotypes of melia, suitable for Kerala. This is one of the reasons which has made a dearth in the availability of good planting material. Hence, a study was conducted to determine the genetic diversity of the trees and select plus trees from the forests of Kerala. Fifteen locations spread over eighteen localities where the species is common were identified from secondary data and reconnaissance survey. In total 281 trees were selected for the survey. The important quantitative and qualitative characters of the trees were determined. Based on baseline selection system, a regression analysis was done between the (DBH)2 x height and (crown width)2 x crown length separately for each location and the trees above the regression line having highest score for the qualitative characters were selected. This was to ensure that a minimum of one tree got selected from a locality to ensure diversity in selection. The study showed that variability existed for all the qualitative characters and it was more within the localities when compared to between localities. In total twenty five trees were selected. Clustering done for the twenty five plus showed that Melia dubia genetic resources resolved the trees into seven clusters and it was found that grouping were independent to the geographic locations. Inter and intra cluster divergence were also studied. The evaluation of the seedling progenies from the twenty five plus trees were done in the nursery for five months. Significant differences among the progenies of the selected trees were observed for various morphological and physiological characters studied. The performance of the progenies of two trees from Tholpetty (FCV-MD-03 and FCV-MD-04) were the best in most of the parameters studied. The genetic analysis of the causes of variation for the morphological and physiological traits were studied. The values for the phenotypic coefficient of variations ranged from 12.62 per cent for height to 24.53 per cent for biovolume. ii The result indicated that the values for genotypic coefficient of variation was less than the phenotypic coefficient of variations for all the traits studied, indicating existence of environmental effect on these characters. Heritability estimates in broad sense were observed higher than 50 per cent for the quantitative characters such as height, collar diameter, number of leaves, AGR and biovolume. Heritability was also higher for all the physiological characters studied. The genetic gain was also high indicating possibilities of using selections for further breeding. The correlation studies on the morphological and physiological characters showed that the height was positively correlated with all the morphological and physiological characters studied except leaf temperature. Photosynthetic rate was positively correlated with the height, chlorophyll and relative water content of the leaves. For standardization of clonal progenies, cuttings from the seedlings, semi hardwood cuttings from mature trees and root suckers by damaging the roots were taken to develop a method for mass multiplication of the Melia dubia. Three different auxins IBA, NAA, IAA at different concentrations were administered. The result showed that the best treatment for the cuttings and rootsuckers were IBA at 1000 ppm. For the semihardwood cuttings, miniclonal technology was used and the best treatment observed was IBA at 6000 ppm.
Open Access
Characterization and identification of black pepper accessions (Piper nigrum L.) for stress tolerance and quality
(Department of plant breeding, College of Horticulture, Vellanikkara, 2019) Prakash, K M; KAU; Jiji, Joseph
Black pepper (Piper nigrum L.), often described as the ‘King of spices’ is the most important spice crop, grown for its berries in the world. Indian pepper is preferred across the globe due to its intrinsic qualities. Foot rot is a devastating disease of black pepper. In the changing climate, drought can be a major threat in black pepper production. Hence, the present study was taken up at College of Horticulture, Vellanikkara and ICAR-IISR, Kozhikode to characterise and to identify superior accessions of black pepper for yield, quality and tolerance to biotic and abiotic stresses. Fifty accessions of black pepper in the bearing stage maintained in the National Active Germplasm Site of ICAR-IISR, Kozhikode formed the base material for the study. The accessions were characterised for fifty qualitative and fifty quantitative characters following the descriptor developed by IPGRI (1995). Wide variability was observed among the accessions for ten qualitative characters. Quantitative characters of shoot, leaf, spike and fruit also showed wide variability. Field tolerance to foot rot disease and pollu beetle infestation was observed among the accessions. Twenty accessions were selected from the base collection based on superiority of yield (> 450g green berries/vine) , field tolerance to foot rot disease infection (biotic susceptibility score 1) and pollu beetle infestation (biotic susceptibility score 1-3). They were further evaluated for biochemical principles of quality, tolerance to foot rot disease under artificial inoculation and tolerance to drought by physiological and biochemical analyses. Piperine, essential oil and oleoresin ranged from 3.61 - 6.96 per cent, 3.00 - 5.87 per cent and 7.10 - 11.18 per cent, respectively, across the accessions. The accessions with high value of piperine, essential oil and oleoresin were identified as 7293, 7211 and 7289 respectively. The two accessions identified viz. 7293 and 7252 contained more piperine than the highest of Panniyur 2 (6.6 per cent) reported among the released varieties . Artificial inoculation of selected accessions using Phytophthora capsici culture for screening for foot rot disease resistance based on over all disease severity index of both stem and leaf lesions showed that accession 7259 was moderately resistant. The selected accessions did not exhibit significant variation for various physiological and biochemical parameters at field capacity. However higher value of photosynthesis, chlorophyll content, chlorophyll stability index, relative water content and membrane stability index and low leaf temperature were observed for accessions viz. 7215, 7240, P 5 and 7241 after five days and ten days of moisture stress induction following field capacity compared to other accessions. Higher values of proline, SOD, catalase and peroxidase were also observed for these accessions. The visual scoring showed that accessions with higher values for most of physiological and biochemical parameters of drought tolerance viz. 7215, 7240, P5, and 7241 had lesser number of fallen leaves and more number of leaves retained at permanent wilting point (PWP). The accessions 7215 and 7240 took twenty days to reach PWP compared to eleven accessions which took only 16 days to reach PWP. Foliar nutrition with sulphate of potash, IISR - Power mix and Pink Pigmented Facultative Methylotrophs (PPFM) had positive effect on drought tolerance for the accessions (7215, 7240, P5 and 7241) having natural tolerance. The identified accessions with high yield , quality and tolerance to biotic or abiotic stress can be used for further breeding programme.
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
Dynamics in prices and trade of Indian small cardmom and its implications on producers
(Department of Agriculture Economics, College of Horticulture, Vellanikkara, 2019) Indhushree, A; KAU; Anil, Kuruvila
Indian small cardamom is known worldwide for its quality and is exported to many countries around the world. Formerly, India enjoyed a monopoly in the production and export of small cardamom in the world. Since 1980s, the country lost its share in the international market to Guatemala due to comparatively higher price and increasing domestic demand for the commodity. The present study on “Dynamics in prices and trade of Indian small cardamom and its implications on producers” was undertaken with the objectives, to study the economics of small cardamom cultivation and marketing, analyse the price formation and transmission between Indian and international markets, study the supply response of cardamom, analyse India’s export performance and competitiveness and assess the implications of changes in price and trade at the farm level. The study was based on both primary and secondary data. In order to estimate the economics of cultivation and marketing of small cardamom, primary data were collected from 160 selected farm households in Idukki district of Kerala and from 52 market intermediaries in Kerala and Tamil Nadu. The secondary data on area, production, prices and exports of small cardamom published by various institutions for the period from 1970-71 to 2017-18 were collected in order to study the price formation and transmission between the international and domestic markets, to find out the export performance and competitiveness of Indian small cardamom and supply response of cardamom to prices. The economics of small cardamom cultivation in Idukki district of Kerala was estimated using the concepts of establishment cost and maintenance cost. The total cost of cultivation and production of small cardamom in Idukki district were estimated as ₹4,79,040 per hectare and ₹375 per kg respectively, while the net returns earned by the farmers was ₹9,18,366 per hectare. The major marketing channels identified for small cardamom were, Channel I: Producer-Village trader-Auctioneer-Wholesaler-Retailer-Consumer; Channel II: Producer-Auctioneer-Wholesaler-Retailer-Consumer; Channel III: Producer-Village trader-Auctioneer-Exporter-Consumer and Channel IV: Producer-Auctioneer-Wholesaler-Upcountry wholesaler-Retailer-Consumer. Majority of the farmers (49 per cent) were selling their produce to the village traders, while 32 per ii cent of the farmers were selling to auctioneers. The marketing efficiency was found to be highest in channel II because of the low marketing cost and margin, and high producer’s share in consumer’s rupee. The marketing efficiency was found to be lowest in channel III. The co-movement between the cardamom prices in the Indian and international markets was confirmed in the post-WTO period, while there was no integration in the pre-WTO period. The transmission of price signals between Indian and international markets was also established for period I, period III and period IV. The price series of different grades of cardamom in the domestic market were found to be moving together in almost all the periods considered. Thus, the price of cardamom in one market was found to be having considerable influence on the price prevailing in the other market after the liberalisation of trade. The Error Correction Model (ECM) indicated the presence of short-run disequilibrium between the Indian and international prices, and between the prices of different grades of cardamom, which got corrected with varying speed of adjustment. Granger causality test confirmed that the price transmission was from the international market to the Indian market in the long-run. The elasticity of supply of small cardamom with respect to its own price lagged by two years was positive and significant in both the short-run (0.39) and long-run (0.96). The rate of growth in the export of small cardamom from India increased, while the instability in export declined in the post-WTO period as compared to the pre-WTO period. The export quantity contributed to about 80 per cent growth in the export value of small cardamom in the post-WTO period. Nearly 85 per cent of change in the variance of export value in the post-WTO period was due to the change in the variability of export unit value of small cardamom. Among the different periods considered for the study, period I recorded a higher growth rate of export and lower instability in terms of value and unit value, while period II witnessed the lowest and negative growth rate with high instability in the export of small cardamom. Geographic concentration of small cardamom export from India always remained high and it further increased in the post-WTO period. Over the years from period I to period V, there was a steady and gradual increase in the geographic concentration of export. There was a changing pattern in the stability of export markets for Indian small cardamom, and the probability of retention of major countries was iii declining over the years with the exception of Saudi Arabia. It was found that Saudi Arabia, Malaysia, Japan and UAE were the stable markets in both pre-WTO and post-WTO periods. Even though India gained considerable market share of new markets viz., UK, Iran and Bangladesh, it lost some of the traditional export markets viz., Kuwait, UAE and Qatar. The export demand for Indian small cardamom was determined by the GDP per capita in the importing countries in both pre-WTO and post-WTO periods, while the export supply was influenced by the ratio of export price to domestic price and the domestic production. The indices of export competitiveness viz., the Nominal Protection Coefficient (NPC) and Effective Protection Coefficient (EPC) values were greater than one (1.33) indicating lower export competitiveness of Indian small cardamom. Domestic Resource Cost Ratio (DRCR) was less than one (0.22) which indicated India’s comparative advantage in the production of small cardamom. Variance in producer prices influences the welfare of the farmers by affecting their income. The variance in exchange rate was found to be the major source of variation in producer prices in the pre-WTO period and period II, while the variance in export unit value was the major determinant in the post-WTO period, period I and period III. The challenges in small cardamom cultivation need to be addressed by introducing varieties that are both pest resistant and high yielding, formulating effective organic inputs and providing replanting subsidy at a reasonable rate to the farmers. Regarding the price and trade of cardamom, crop specific price stabilization mechanism is needed to tackle the excessive volatility in cardamom prices. More transparency is required in the e-auction system to reduce re-pooling by traders and ensure faster payment to the farmers. In order to promote export and improve India’s competitiveness, farmers should be encouraged to follow Good Agricultural Practises (GAP) that will help to reduce the input usage, which will in turn improve the quality of the commodity and reduce the cost of production. Effective ban on toxic chemicals at the national level is necessary to keep the residual toxic content in small cardamom within the permissible limits. Branding of Indian small cardamom which is of superior quality could also help in promotion of the commodity in the international market.
Open Access
Process optimisation and quality evaluation of cocoa based chocolates
(Department of Community Science, College of Horticulture,Vellanikkara, 2019) Shahanas, E; KAU; Seeja, Thomachan Panjikkaran
Cocoa (Theobroma cacao) is a supporting crop to farmers due to its remunerative income, which forms the basis for one of the world’s most popular food products chocolate. The quality of final product depends upon the fermented dried beans. High free fatty acid content is a serious quality defect and reduces the economic value of the cocoa beans. Recently, the cocoa trade has assumed a more scientific position and a lot of emphasis are placed on the content of free fatty acid. A reduction in the free fatty acids level will definitely have a positive impact. As such there is a need for the farmers to carry more intensive research and to develop and technology for the standardisation of free fatty acid content in the processing stages of cocoa in both primary and secondary processing. The present study was undertaken to develop protocol for primary processing of cocoa beans based on free fatty acid content (<1.75 %), to standardise the time and temperature of chocolate making using machine and to evaluate the quality attributes and shelf life of the products. Cocoa fermentation was carried out with three different types of fermentation methods like basket, heap and sack method for the periods of 5, 6 and 7 days of fermentation with nine different treatments. The physico-chemical qualities of fermented cocoa beans were evaluated. The highest (84.99%) fermentation index or cut test score was recorded in heap method at seventh day of fermentation (T6). The highest fermentation bean recovery of 84.33% was noticed in treatment T4 in heap method at fifth day of fermentation. The moisture content vary from 50.40 %, 53.67% and 54.40% to 39.80%, 37.83% and 39.43% from initial to seventh day of fermentation in sack, heap and basket method respectively. The pH of fermented beans varied from 6.11 to 4.26 in all methods. Among the fermentation methods the maximum fat content was in heap method from initial 42.66% to 32.89%. The lipase activity, decreased with fermentation periods in all three fermentation methods. In heap method it varied from 0.0022 to 0.0005. The heap method with seven days of fermentation were selected to sun drying and oven drying based on the lowest free fatty acid content (0.80%). The bean recovery of fermented dried beans was high (41.00 %) in sun dried cocoa beans as compared to oven dried beans (40.12 %). The free fatty acid content (1.26 %) in sun dried cocoa beans was less compared to 1.47% in T2 (oven dried beans). The moisture content (3.76%) and lipase activity (0.0018μ eq) was less but, the fat content and pH was high in sun dried beans. The sun drying proved to be adaptive as free fatty acid content was lower than oven dried beans and were below the cut off value of 1.75%. The sun dried beans were stored in gunny bags (control), polythene covers and plastic containers under ambient condition for a period of six months and the physico-chemical qualities of stored cocoa beans were done initially and at an interval of one month for a duration of six months. The highest bean recovery (98%) and least moisture content (4.22 to 4.52) was in cocoa beans stored in plastic container at the end of sixth month of storage. The lowest free fatty acid content of 1.68% was in cocoa beans stored in plastic container at sixth month after storage. The stored cocoa beans in plastic container were divided into two lots, one lot was used as such and the second lot was subjected to alkalisation. The chocolates was prepared with alkalised and non alkalised cocoa beans in tempering and conching machine for different time periods of 7, 9 and 11 hours at a temperature of 600C and 700. After the preparation of different types of alkalised and non alkalised chocolates in tempering and conching machine, chocolates were subjected to analysis of physico-chemical qualities, organoleptic evaluation and for enumeration of microflora. The treatment T6 (Chocolate prepared at 700C for 11 hours) and T12 (700C for 11hours) had the lowest free fatty acid content of 1.67% and 1.68% and maximum score for overall acceptability (8.89 and 8,87). Chocolates prepared at 700C for 11 hours from alkalised and non alkalised beans were blended with dehydrated grapes, dehydrated dates, osmodehydrated jackfruit, osmodehydrated pineapple, badam, cashew nut, powdered dehydrated mint leaves and white pepper powder. From the, organoleptic evaluation of different treatments, the best rated treatments from alkalised chocolates were T3 (95 % alkalised chocolates +5% osmodehydrated jack fruit), T6 (95 % alkalised chocolates +5% badam) and T8 (95 % alkalised chocolates +5% white pepper) and from non alkalised chocolates the treatments T11 (95 % non alkalised chocolates +5% osmodehydrated jack fruit), T14 (chocolate blended with 95 % non alkalised chocolates and 5% badam) and T16 (95 % non alkalised chocolates and 5% white pepper powder) were selected, packed in aluminium foil and stored in refrigerator for six months. Initially the lowest hardness of 74.41N and 76.71N was recorded in controls (T0 - AC) and (T0 – NAC. The maximum energy content of 580.15Kcal was found in treatment T5 (95 % NAC+5% B). Initially the maximum protein content (7.74 g/100g) was noticed in treatment T2 (95 % AC+5% B) and T5 (95 % NAC+5% B). The highest polyphenol content ranging from 0.23g/100g to 0.19g/100g was seen in T0 (100% NAC) throughout the storage periods. A reduction in mineral contents like calcium, phosphorus and iron content was observed in all treatments and at the end of sixth month calcium content varied from 0.39g/100g to 0.63g/100g. An increase in lipase activity and free fatty acid content of blended chocolates was recorded during storage and FFA was within 1.75% up to fourth month of storage. Based on organoleptic score, the treatment T2 (95 % AC+5% B) attained the highest rank. The blended chocolates were evaluated for the presence of bacteria, yeast and mould initially and monthly intervals for a period of six months, At the end of sixth month of storage the highest bacterial count of 2.0 x 104 cfu/g was found and during sixth month of storage. The cost for blended chocolates was varied from Rs.46.54 to Rs.50.62 / 40 g of chocolate bar. The cost of the chocolates prepared in the present study was lesser as compared to the commercial chocolates. The present study found that good quality, nutritious and healthy blended chocolates using cocoa could be prepared without adding any preservatives. The blended chocolates contain treasure of nutrients and bioactive compounds polyphenol which is essential for the growth and development of children and also give several health benefits.
Open Access
Morpho-Molecular charaterisation of intergeneric hybrids of Ascocentrum
(Department of Floriculture and Landscaping, College of Horticulture, Vellanikkara, 2019) Katare Renuka, Shamrao; KAU; Sobhana, A.
Morpho-molecular characterisation intergeneric hybrids of Ascocentrum was conducted at the Department of Floriculture and landscaping, College of Horticulture, Vellanikkara, during 2016-19 with the objective of characterising based on morphological and molecular analysis for commercial exploitation and compatibility assessment. Thirty varieties selected for the morphological characterisation. In quantitative characters Mok. Omayaiy Yellow showed highest plant height, internodal length and leaf breadth throughout the study period. Plant spread, leaf length and leaf area were highest in Kag. Youthong Beauty. Mok. Sayan × Ascda. Doung Porn was observed with highest shoot girth, shoot diameter and number of leaves. Ascda. Yip Sum Wah × V. JVB showed maximum number of roots, Mok. Khaw Phiak Suan × Ascda. Jiraprapa was observed with the highest root length and Mok. Chao Praya Sunset Yellow Spot with the highest root girth. Vasco. Aroonsri Beauty had the least values in all vegetative characters throughout the study period including plant height, spread, internodal length, shoot, leaf and root characters except the number of leaves which was the least in Mok. Khaw Phiak Suan × Ascda. Jiraprapa. Variety Vasco. Aroonsri Beauty also produced the maximum number of florets/spike and had the shortest internodal length. Cluster analysis with 14 different floral characters revealed 12 clusters at 75 per cent similarity. The highest inter-cluster distance was observed in cluster 6 and cluster 10. Cluster 6, which included Ascda. Sirichi Fragrance and Vasco Blue Bay White was found to have the lowest internodal length with the highest value LVII for number of florets per spike, also observed to have lower flower length and flower width. Cluster 10 was found to have the high mean values for spike length, flower length and flower width. In qualitative characters, based on growth habit, two types were found among the varieties viz., hanging and prostrate nature of growth. Leaf texture was found smooth and rigid with entire leaf margin. Leaf apex was acute in Vasco. Aroonsri Beauty and Ascda. Yip Sum Wah × V. JVB and was emarginated in rest of the hybrids. Wide variation was found among the flower colour, colour pattern, nature of petals and lip. Regarding post harvest traits, variety Mok. Omayaiy Yellow recorded highest fresh weight of spike and physiogical loss in weight. Whereas, variety Kag. Youthong Beauty took maximum days to start wilting of a floret. Mok. Chark Kuan Pink was observed to have longest vase life, spike longevity and highest water uptake. In visual evaluation the highest total mean score for the spike to use as a cut flower was observed in Mok. Omayaiy Yellow (54.6 out of 60), while the lowest was observed in Vasco. Blue Bay White. The highest mean score was obtained in Vasco. Pine River Pink (53.83) for plants for the indoor display. In pollen studies Ascda. Sirichi Fragrance and Mok. Sayan × Ascda. Doung Porn showed the highest pollen fertility and germination and these were selected as two male parents for further cross compatibility check. Vasco. Aroonsri Beauty and Kag. Youthong Beauty were found self-incompatible as well as cross incompatible with both the male patents and Vasco. Pine River Blue was found cross incompatible with Mok. Sayan. × Ascda. Doung Porn whereas, the rest of the varieties were found cross-compatible with both the male parents. LVIII Among the 21 SSR primers, ten generated polymorphic patterns. The number of amplicons detected varied from two to seven. The highest number of alleles was found in FJ539054, FJ539061 and JN375718. Primers DQ494847 (3) observed to have less number of amplicons. The PIC value ranged from 0.095 to 0.800.. One unique band was produced by JN375713 and FJ539050 primers in Kag. Samrong and Vasco. Aroonsri Beauty, respectively. The least Jaccard’s similarity value (0.05) was observed between Kag. Samrong and Ascda. Suksamran Sunlight, Ascda. Yip Sum Wah × V. Josephine Van Brero, Vasco. Aroonsri Beauty. The UPGMA clustering algorithm grouped the varieties into two main clusters. The variety Kag. Samrong clustered separately from all other members, whereas, other members were grouped in one cluster. At 50 per cent level of similarity, the hybrids grouped into 13 clusters. Out of 29 ISSR primers used, 20 showed amplification in all hybrids with polymorphic bands. ISSR primer (GACAC) 4 generated 11 amplicons, whereas, ISSR 901 generated 31 amplicons. ISSR primer (GACAC) 4 had lowest PIC value, and UBC810, the highest PIC value (0.926). The least Jaccard’s similarity value (0.03) was observed between Vasco. Blue Bay White and Mok. Khaw Phiak Suan × Ascda. Bicentennial Yellow Spot, which indicates that these hybrids are dissimilar to each other. The highest Jaccard’s similarity value was observed between Mok. Khaw Phiak Suan × Ascda. Bicentennial Yellow Spot and Mok. Chao Praya Sunset Yellow Spot. A UPGMA-based dendrogram separated the 20 hybrids of Ascocentrum orchids into two main clusters, each with 10 members. At 30 per cent level of similarity, all the 20 hybrids grouped into 14 different clusters. Six clusters were observed with two members each.
Open Access
Taxonomy and organic carbon-nutrient interactions in selected wetland soils of Kerala
(Department of Soil Science and Agricultural Chemistry, College of Horticulture, Vellanikkara, 2019) Nideesh, P; KAU; Sreelatha, A K
A study was undertaken with the objective to classify wet land soils in the agro ecological units AEU 10 (north central laterite), AEU 5 (Kole lands) and AEU 6 (Pokkali lands) of Kerala and to assess the organic carbon stocks and CNPS stoichiometry. The study also aimed in finding out the organic carbon - nutrient interactions and to predict the organic carbon turnover in these soils. Extensive field traverse was conducted to select sites for profile excavation in the lateritic, Kole and Pokkali wetlands. The excavated profiles were studied for their morphological, physical and chemical properties. Based on the results of the study, soils of lateritic wetlands were classified as fine loamy, mixed, super active, acid isohyperthermic, Fluventic Dystrustepts. Soils of Kole lands were classified as loamy, mixed, euic, isohyperthermic, Terric Sulfihemists and Pokkali soils as coarse loamy over sandy, mixed, active, isohyperthermic, Typic Sulfaquepts. Total soil organic carbon (SOC) stock in the north central laterite region (Fluventic Dystrustepts) was 218 Mg ha-1 up to the depth of 120 cm of which maximum amount was stored in the surface 30 cm (86 Mg ha-1). In the Kole land soil (Terric Sulfihemists) maximum SOC was stored in the 90-120 cm layer (1016 Mg ha-1) and a total SOC of 2261 Mg ha-1 was stored up to 120 cm depth. Pokkali soils (Typic Sulfaquepts) stored 209 Mg ha-1 SOC up to 120 cm depth which was almost uniformly distributed in the entire profile. The C/N, C/P and C/S ratios decreased with depth in lateritic soil profile, whereas in the Kole land soil these ratios except C/S ratio increased significantly in the sub surface horizons. In the Pokkali soils the CNPS stoichiometry suffered irregular variation with depth. An incubation experiment was conducted to study the organic carbon nutrient interactions in the three wetland soils. Treatments included control (T1), POP based fertiliser and lime application (T2), soil test based fertiliser and lime application (T3), FYM substituting nitrogen in the T3 treatment (T4) and soil test based fertiliser and dolomite application (T5). In the lateritic soils. the active carbon and organic reserves of N, P and S were high in T3 treatment. The organic N, P and S pools increased in treatment T5 whereas organic P and inorganic S increased in treatment T4. In the Kole land soils, active carbon, organic nitrogen, inorganic P, organic S and inorganic S increased in T3; inorganic N and organic P increased in T4 and organic P and S pools increased in T5. In the Pokkali soils, active carbon content was high in T2 compared to other treatments while active carbon, organic N and inorganic N decreased in treatment T3. Liming decreased organic P in Pokkali soils due to conversion to available forms and higher utilisation. Application of FYM increased organic S in Pokkali soils and inorganic S in all soils. Temporal variation of the nutrient content (mg kg-1 soil) per organic carbon content (g kg-1 of soil) indicates the change in nutrient supply per unit change of organic carbon content. Treatment T1 favoured higher inorganic nitrogen per carbon content in laterite and Pokkali soils, where as in in Kole soils it was increased in T4. Inorganic phosphorus content per carbon was highest in laterite and lowest in Kole soil in control (T1). Inorganic sulphur per carbon content was highest in T4 for laterite, Kole and Pokkali soils. Organic nitrogen per carbon content was highest in the Kole land and minimum in the Pokkali land in the T3 treatment. Organic phosphorus per carbon content was maximum in FYM treatment in Kole and Pokkali soils and was minimum in T2 treatment in laterite and Pokkali soils. Treatment T3 had the highest organic sulphur per carbon content in the laterite and Kole soils and the treatment T1 gave the highest content in Pokkali soil. Wetland DNDC model was used to simulate the organic carbon turn over in the three wetland systems using the climatic data predicted by MarkSIM software. The results of modelling simulated for the year 2050 indicated that application of 100 per cent NPK along with FYM @ 5t ha-1 will ensure maximum organic carbon content in the Kole, Pokkali and lateritic wetlands. Fertiliser application improves the organic carbon storage in lateritic and Kole land soils. But in the Pokkali soils, fertiliser addition will not cause change in the organic carbon turn over processes whereas FYM application can improve the carbon content. Results of the study indicate that cultivation without any fertiliser and lime application causes gradual depletion of all organic and inorganic pools of nutrients in Kole land and lateritic wetland soils. Soil test based fertiliser and lime application along with FYM @ 5t ha-1 is appropriate in these soils for increased sustainability. The Pokkali soils are self-sufficient and can sustain its fertility status without any fertiliser application. However liming and FYM application may be considered as management options to improve sulphur availability and organic carbon turn over processes in these soils.
Open Access
Dynamics and competitiveness of agricultural trade polices on coconut economy of Kerala
(Department of Agricultural Economics, College of Horticulture, Vellanikkara, 2019) Thasnimol, F; KAU; Prema, A
Coconut is a crop of economic importance in many Asian and Pacific countries. India is the largest producer of coconut in the world contributing 23798.23 million nuts from an area of 2.09 million ha (CDB, 2018). The economic reforms of the 1990s and the subsequent trade liberalization policies have brought challenges and prospects to Indian agriculture including the coconut industry. In this context, the present study was undertaken with the objectives to trace and assess the impact of trade policies in edible oil on coconut economy of Kerala, to analyse the price transmission in the markets, to estimate the efficiency of selected coconut markets and finally to suggest appropriate policy measures for improving the performance of coconut trade. Both primary and secondary data were used for examining the specific objectives of the study. The primary data were collected using well-structured and pretested schedules through a survey of 90 farmers, 45 market intermediaries and 15 exporters in the selected districts of Kerala. Secondary data was mainly collected from authentic sources like CDB, EXIM data bank, DGCI&S, DGFT and FAO statistics. Though trade liberalization adversely affected the coconut farmers during the initial phase of liberalization, it subsequently increased the opportunities of the Indian coconut sector to compete in the world market. The export growth rate of coconut products has increased during the study period (1980-81 to 2016-17) while instability index, a measure of export stability was found to have decreased. The high growth rates of coconut products together with low instability indices in the export revealed the prospects for Indian coconut sector in the global market. Hence stream lining the production through Good Agricultural Practices to fulfill the export market requirements with regard to quality and safety would boost the trade. The comparative advantage in coconut trade analysed using the Revealed Symmetric Comparative Advantage (RSCA) indicated that coconut oil and desiccated coconut did not possess any comparative advantage in global trade, while coconut (fresh and dried) and copra have comparative advantage. It was obvious from the result that rather than focusing on the export of coconut oil and desiccated coconut, India must give much effort to increase our export share of coconut, copra and other value-added coconut products to augment the foreign earnings. The trade policies concerning edible oils at the national level were found to have an impact on the coconut oil prices in Kerala too. Exponential growth rates were computed to compare the growth of edible oil imports and coconut oil prices in Kerala. The significant improvement in the growth rates of edible oil import and decline in the growth rates of coconut oil price confirmed that trade liberalisation and further Free Trade Agreements (FTAs) facilitated the huge import of edible oil from other countries which unfavorably affected the domestic coconut economy. The result of the Policy Analysis Matrix (PAM) unveiled that coconut oil production in Kerala was competitive at the given level of technologies, prices of inputs and outputs and current policy stipulations. However, social profitability, a measure of efficiency or comparative advantage was observed to be negative. The result depicted that coconut oil production in Kerala lacks comparative advantage in production and the state was not able to use the available resources efficiently. The efficiency of selected coconut markets studied using Shepherd’s index indicated that the presence of more number of marketing intermediaries and high marketing cost and margin have reduced the producer’s share in consumer’s rupee. Besides, high wage rates, shortage of skilled labour, lack of processing technologies, adverse climatic conditions, etc., obstruct the farmers in performing even the primary level processing and thereby it reduces the producer’s share in consumer’s rupee. The cointegration analysis using Johansen Cointegration method revealed that the liberalisation policies and further free trade agreements have resulted in the transmission of price signals between domestic and international edible oil markets and it led to the integration of these markets during the post-liberalisation period. The result of Vector Error Correction Model (VECM) also depicted that changes in the international prices of edible oils would cause changes in price in the domestic coconut oil market in the long-run. High wage rate, labour shortage and incidence of pest and diseases were the major production constraints faced by the farmers. Inclusion of agricultural operations also under MGNREGA has been suggested by farmers as an option for bringing down the cost of cultivation. Shortage of skilled labours can be lessened through the adoption of programmes like Friends of Coconut Tree (FoCT). The problems related to pest and disease attacks can be addressed by developing resistant and hybrid varieties and better plant protection measures. Price fluctuation, high transportation cost, inadequate storage and processing facilities were the major marketing constraints faced by the farmers. Long-term policies for the price stabilization of coconut and other coconut products are inevitable to reduce the price fluctuation. The government should continue the procurement operation through Krishi Bhavans as it is found to be beneficial for the farmers. Shortage of raw nuts, lack of exclusive market for coconut and high domestic price were the major constraints reported by the domestic traders and upcountry traders. The recent surge in the domestic price could be attributed mainly to the short supply coupled with high domestic and industrial demand. Shortage of raw nut due to lower production, productivity and pests and diseases needs to be addressed seriously. In the era of trade liberalisation and FTAs, the interests of farmers also need to be safeguarded while concentrating on trade opportunities. Given the present trade scenario, the coconut sector in Kerala needs strong support from the government to revive and retrieve its premier role performed in the past.

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